Design of a chewing gum that does not fouls the streets and is digestible

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Conceptual Product Design CPD 3286

Process Systems Engineering DeiftChem T ech - Faculty of Applied Sciences Delft University of T echnology

.

Subject

Design of a chewing gum that does not fouy the streets and is digestible

~ti

T

U

Delft

Technische Universiteit Delft

Telephone nr.

+

31641189199

+

31628238002

+

31 61 4476383

Study nr.

9605015

9646305

9932134

Authors

Noro Nikolie Sander van Pelt Helene Webers

Keywords

Chewing gum, poly(vinyl alcohol), street fouling, product design

Assignment issued Report issued Appraisal

Faculteit Technische Natuurwetenschappen Scheikundige Technologie en Materiaalkunde

17-02-2003

10-05-2003

27 -05-2003

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Delft University of T echnology, Conceptual Product Design CPD3286

Acknowledgments

We would like to thank Prof. Ir. G.J. Harmsen for agreeing to supervise our project; dr. Ir. H. van der Kooi for his patience, guidance and critica I comments; Ir. I.Nikolic for his assistance in structuring our thoughts; Ir. G. Korevaar tor stimulating ideas concerning chemical product design; RBV LEAF for the cooperation on this project; Mr. AC.M. van Geffen for saving us from computer problems; T.J. Faber for his critical notes and thoughts on product design.

Noro Nikolic, Sander van Pelt and Hélène Webers Delft, May 10th 2003

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Delft University of T echnology, Conceptual Product Design CPD3286 ii

Executive summary

This report is the result of Conceptual Product Design assignment "The design of a chewing gum that will not foul the streets and is digestible". The goal of this project is to formulate a detailed product design, consisting of product target specifications, technical feasibility, market analysis and economic feasibility. This report constitutes the detailed design and the prelude to it.

The design is approached by making use of chemical product design procedure developed by Korevaar and the CPD manual by Frens. The Korevaar procedure is divided into four phases according to Frens. The Design Team has developed specific design tools and applied creative methods during the performance of the design.

The designed product is a chewing gum th at retains its chewability, freshness and taste quality for a period of 1S min, after which it gradually becomes smaller by dissolving while retaining its

chewability, until it eventually totally dissolves in the mouth. In this way, the problem of street fouling

I

is tackled at the root of the problem: people are encouraged not to take the chewing out of their Vvo

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mout anymore. The number of chewing gums disposed on the streets wil I show an

immense/~

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creas . The designed product is a chewing gum product based on poly(vinyl alcohol) polymer V"OJ-{. gum base in combination with glycerin plasticizer, calcium carbonate filler, xanthan gum thickener,

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xylitollsorbitol sweetener, menthol flavour, lecithin emulsjfier and butylated hydroxyanisole

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antioxidant.

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The designed product is positioned as a regular sugar-free chewing gum with several added values. The primary targeted consumer groups are Young Urban Professionals and Double Income No Kids couples, in the age group of 20 to 35. The designed product is marketed as an excellent substitute for conventional chewing gum with the prime added value of improved taste rete~tion and a secondary added value of no residual waste.

----

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T argeted sales are X% of the Sportlife and Y% of the Xylifresh market segment. This amounts to annual sales of 28.5 mln. packages of the designed product. The calculated retail price of the designed product is €0.70 per package of twelve gum pieces. The selling price of the chewing gum to the retail shop will be

€O.SO.

The break-even point is reached within 6 months of operation. The safety and health analysis shows that the designed product is safe for human consumption. The critical consumption quantity

of

the designed product is more than 3400 pieces. It is established that the degradation products of individual ingredients are not harmful for humans. A life Cycle Analysis of the designed product showed that he energy consumption of the ingredients stage of the designed product will be higher than for the conventional chewing gum. The saved external costs by using the designed product are

€O.ll

per functional unit.

If

the designed chewing gum still happens to be disposed on the street, it can be removed by using water of about 37

oe.

The dissolved poly(vinyl alcohol) chewing gum can be enzymatically degraded by micro-organisms.

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Delft University of T echnology, Conceptual Product Design CPD3286 iii

Ta

bie of contents

Introduction ... 1

1 .1 Project goals and restrictions ... 1

1.2 Creation of the Design Assignment ... 2

1.3 Problem introduction ... 7

1 .4 Cooperation ... 9

2 Applied design method ... 11

2.1 General design method ... 11

2.2 Design tools and creative methods ... 12

2.3 Design-Roadmap ... 16

3 Material options and selection ... 17

3.1 Identification of needs ... 17

3.2 Function analysis ... 21

3.3 Design Problem Definition ... 30

3.4 Brainstorm and selection of ideas ... 31

4 Basis of Design ... 35

4.1 Product requirements ... 35

4.2 Description of 4 possible material options ... 36

4.3 Material selection and definition of Designed Product ... 51

5 The Integrated Product Concept ... 57

5.1 Introduction ... 57

5.2 Composition determination of PVOH chewing gum ... 57

5.3 Production process of PVOH chewing gum ... 62

5.4 Availability of basic ingredients ... 66

6 Target Specifications ... 70

6.2 PVOH chewing gum ... 70

6.3 T echnical Target Specifications ... 70

6.4 Marketing Target Specifications ... 71

6.5 Sales Target Specifications ... 71

7 Marketing analysis ... 72

7.1 Description of product and market ... 72

7.2 Market analysis ... 74

7.3 SWOT ... 75

7.4 Marketing strategy ... 77

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Delft University of T echnology, Conceptual Product Design CPD3286 iv

8 T echnical feasibility ... 79

8.2 T echnical implieations of solution stated in TS ... 79

8.3 Material speeifieations and implieations of integration of ingredients ... 80

8.4 Safety, health and environment (SHE) ... 109

9 Economics ... 11 7 9.1 Assumptions ... 117

9.2 Totallnvestment Cost ... 118

9.3 Annual Operating Costs ... 120

9.4 Economic Criteria ... 121

9.5 Economie Feasibility ... 122

10 Conclusions and Recommendations ... 124

11 Literature ... 125

Appendix 1 Brainstorm ideas ... 130

Appendix 2 Questionnaire Chewing Gum ... 131

Appendix 3 Results from questionnaire ... 134

Appendix 4 Scoring range of Selection Criteria Table ... 136

Appendix 5 SusCon Analysis of 4 material options ... 137

Appendix 6 Calculation of purehase eost of equipment ... 138

Appendix 7 Ca/culation of T otal Required Investment Capitai ... 139

Appendix 8 Raw material, Utilities and Labour Costs ... 140

Appendix 9 Ca/culation of Operating Costs ... 142

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1 Introduction

This report is the result of a Conceptual Product Design assignment. The goal of this project is the formulation of a detailed product design, which consists of product target specifications, technical feasibility, market analysis and economie feasibility. The assignment is "The design of a chewing gum that will not foul the streets and is digestible". This report constitutes the detailed design and the preamble to it.

The goal of this chapter is to outline the framework of this Conceptual Product Design project. The chapter will start with a description of the project goals. Subsequently, the creation of the assignment will be described and on introduction into the chewing gum street fouling problem will be given. The chapter ends with a description of the approach and of the institutions with which was cooperated.

1 .1

Project goals and restrictions

The goals of this project are partly defined by the department of Chemical Engineering of the Delft University of T echnology, and partly by the Design Team itself. Some goals and restrictions of the Conceptual Product Design (CPD) are laid down in the Guidelines of CPD (Frens 2001). Additionally, the Design Team members defined personal goals for this project. The combination of these goals constitutes the goals of this project and will be described hereinafter .

.L..Ll

Goals and restrictions of the CPD project

The Conceptual Product Design (CPD) is a project situated in the first year of the Master of Science education in Chemical Engineering. According to the Guidelines of CPD (Frens 2001), the CPD project is defined as on opportunity for students to develop the essential skilIs for the creation of a Conceptual Design of a chemical Product or a chemical Process. The project is usually performed by a team of three to five students and therefore enables the students to further their experience in teamwork. The CPD project will demonstrate the students' ability to transform their creativity and gathered technical knowledge into on integrated design within a fixed period of twelve weeks.

The design work includes analysis of the needs and functions of the product, design problem definition, generation of ideas, basis of design, integrated product concept and detailed design. The detailed design includes technical feasibility, market analysis, economie feasibility and on analysis of safety, health and environment aspects concerning the designed product. The result is a report that describes the design process and the product that offers a solution for the defined problem.

1 .1 .2 Personal goals of the Design Team

The Design Team consists of three students of the department

of

Chemica I Engineering: Noro Nikolie, Sander van Pelt and Hélène Webers. Besides the goals mentioned above, the Design Team

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2

formulated some specific goals as a result of expectations and personal learning goals. The Team members had the collective feeling that the design had to tackle an environmental problem. Furthermore it was seen as achallenge to deliver a qualitative design within a fixed period of time. As the CPD project is the first design assignment in the curriculum, the acquisition and application of a design method was another learning goal of the team members. The CPD is also the first project in the curriculum th at gives the opportunity to students to apply and implement the academie knowledge of different fields in one project. Finally, the team members expected to learn from each other, as weil in the field of personal and social skills as in the field of academic learning.

The defined project goals are summarised in T able 1.1 beneath.

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pro/ec goa . t

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Defined Goals

Conceptual

-

Develop essential skilIs for a conceptual product design Product

-

Experience in teamwork

Design

-

Transform creativity and gathered technical knowledge into on integrated design

-

Deliver a design in a fixed period of time of twelve weeks

-

Design of a product that offers a solution for the defined problem Design

-

Find a solution for on environmentol problem

Team

-

Acquisition and application of a design method

-

Application of gathered academic knowledge of a variety of fields in one project

-

Learning from other team members

1 .2

Creation of the Design Assignment

In this section the creation of the Design Assignment will be explained. In regular Conceptual Process Design the choice

of

assignment is not arbitrary but is assigned by the project coordinator. As there was no official Conceptual Product Design Assignment availobie, the Design Team had to create its own assignment. This immediately became the first creative challenge for the Design Team.

The Design Team was given a week to come up with several ideas for a Design Assignment that would be presented to the project coordinator, the Principal and the Creativity Coach. The first Design Team discussion took place on a genera I level about which topics the different team members found interesting. Several brood areas of interest and preference were discussed. The outcome of the meeting was twofold. The Design Team shared the desire to work on the solution of on environmental problem. Furthermore the designed product had to create a radical sustainable improvement. At the end of the meeting the Team decided it needed a structured approach for the ge selection of specific assignment ideas. A suggestion was made to approach on e ernal facilito ~~ach the Team during a brainstorming session. The idea was approved and a

ate or the session s\ ~ ~

The brainstorming session was approached in four consecutive steps and lasted for about 2 hours. The Team made use of posters hung up on the walls of the CPD room and achalkboard for writing down the ideas.

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3

1.2.1 Step 1. Associative words with: sustainable, product and design

The first step was a random association of words on three keywords: sustainable, product and design. T able 1.2 below shows the results of these associations.

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Sustainable Product Design

Renewable Thingy Creating

Environmentally friendly Function Making Not burdening the future Need Solving

Economic Application Process

Damage correction Useful Improve

Image Aid Analysis

Social acceptance Marketing Creative

Long term Sales New

Clean Amount Design

Safe Unit Criteria

Bio-degradable Price Wishes

Nature-freaks Quality Demands

Eco-store Feasibility Make-able

Green Wishful

Energy efficient Package Profit

1.2.2 Step 2. Formulation of statements

The second step was a formulation of several statements by each Team member, each statement containing at least one word from each column. The list of created statements is shown in T able 1 .3.

T able

7.3

Created statements

from assignment generation brainstorming

session

• Environmentally friendly characteristics of a product are important design criteria. • A green image is preferabie.

• A damage-repairing characteristic would be a useful function th at really provides a solution. • Making a product th at is biologically degradabie usually results in a higher price of the product. • Because of the sustainable characteristics of the product, the price can be higher.

• Social acceptance is an important criterion for sales.

• Designing a product that has a long-term function requires a very good analysis of the problem. • Is it advisable to sell the product in a reform store?

• You have to make sure that the product has all the right eharacteristies without it getting a "goat wool soeks" image.

• Designing is making a sound analysis with a creative solution.

• A solution needs to be found th at is clean, safe, environmentally friendly but still feasible. • The creation of a product that repairs damage in the long term and does not have any bad

effects in the future is desirabie. • Producing and selling a clean product.

• Efficient cars have good sale figures beeause of the cost criteria.

• The sustainable image causes the resulting higher price to be less of a eriterion. • Biologieally degradabie fishing line can be applied to improve the image of angling. • Stimulating efficient usage ean be a function of a ereative design.

• Social aeeeptance of the sustainability function of a product design is large in the western world. • Sustainable products often have a higher priee but they increase the chance of a green future.

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4

• Creating a combination of a product that is environmentally friendly and a product that fulfils

other demands and wishes.

• The creation of a clean instrument for a long-term usage.

• Creatively repair damage done to the environment by conventional processes. • What is the feasibility of an economie and environmentally friendly process? • Can profit and demands in the sustainability of a product be combined? • How big is the demand for environmentally friendly processes?

1.2.3 Step 3. Design Relation T able

The third stage of the brainstorming session was to find specific terms th at are used by all of the Team members and look for relationships between those terms. T able 1.4 shows the resulting Design Relation Table.

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PRICE ENVIRONMENT

IMAGE

f-CREA TIVITY ~ EFFICIENT

QUALITY GREEN

EFFECT SAFE

Table 1.4 reflects the force field in which the design assignment will be situated. Creativity will be necessary to solve the problem with a solution in which the price, image, quality and effect are balanced with environmental aspects, efficiency, green character and safety.

1.2.4 Step 4. Generation of product assignment

The fourth stage was the actual generation of Design Assignment options that fit within the Design Relation Table (Tabie 1.4). The team members held a brainstorming session to generate a list of problems relevant to the Design Relation Table. During the brainstorm The Team generated an extensive list of possible problem perpetrators (Tabie 1.5).

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5 T able

7.5 :

Ust

of

possible problem perpetrotors relevant

to

the Design Relation T able

Oil refineries Waste of ecological resources

Stripping down of ships Environmental pollution Dosage of detergents Chewing gum pollution

Fashion Noise pollution

Dying of clothes Cellular phones

Cars Expensive residues

Bulk chemicals Drainpipe cleaner

Bio chemicals (expensive) Non-staining deodorant

Pesticides Fire extinguisher

Airplanes Labels for food

Bio degradabie detergents - Dryer

(not effective) Separation of garbage

Cans Oil

Rubbish Cigarettes

Rubber (tires) Cardboard

Meat Fireworks

Fertilizer Cleansing agents

Consumer society Chemical waste

Throw-away goods Synthetically bio products

Plastic cups Nuclear waste

Furniture Solvents

Plastic Feit-tip pens

Water dissipation T 00 much food dissipation

As

a result of the possible problem perpetrators, another list with possible products was generated (Tabie 1.6).

Table 7.6: Ust

of

possible produds relevant

to

the Design Relation Table

Detergent that speeds up the drying process as an alternative for a dryer Alternative for fireworks

Biologically degradabie fishing lines

Solution for the problem of street fouling caused by chewing gums Products that make use of waste from the paper industry

Diapers that produce less waste

Solution for problem of polar pollution in drinking water due to excretion of oestrogen

Alternative for environmentally unfriendly conventional strip down of ships Alternative for dying of clothes (cotton)

Bad odour neutraliser for waste baskets for green waste Alternative for heavy metals in catalysts

Alternative for pesticides used for cultivation of cotton

In order to make a selection of four potential product assignments a

+/-

evaluation method was applied. Team members awarded plusses to topics for being:

+

more interesting than others (personal preference)

+

more challenging

+

more suitable for the project length of 12 weeks

+

better fitting within the Design Relation T able

Every Team member was allowed to award 5 plusses and 2 minuses for potential product assignments one preferred or disliked. In this way the potential product assignments were ranked.

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₆

After elaborate discussion of the ranked listed a final list of top-four assignment options was selected for evaluation with the project management. The top-four list was:

1 . Solution for the problem of street fouling caused by chewing gums 2. A more energy-efficient way of drying clothes without the use of a dryer 3. Diapers that produce less waste

4. Biologically degradabie fishing lines

The Team members evaluated the four options during a joint meeting with the project coordinator, the Principal and the Creativity Coach. Because the option No.1 was most preferred it was decided th at the Team would take this as their assignment.

1.2.5 Generation of Assignment Statement

As

the assignment was formulated, it was necessary to get a precise idea of the scope of the assignment and to generate on exact Assignment Statement. A brainstorming session (Appendix Q1) was held to explore the boundaries of the problem. As a result of this brainstorm session, the proposed assignment was separated into three problem areas:

1) Swallowing chewing gum is not healthy

2) Removing chewing gums already on the streets

3) An alternative chewing gum that is biologically degradable

These three areas were assessed on 'interesting' and 'suitable for the project'. An evaluation table with weighing factors was used for this purpose. The evaluation table is shown in Table 1.7.

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Weighing 1 2

3

1+3 factor Interesting 6

9

8

9

10 54 48 54 60 Suitable for

4

+++ + +++ ++ project 40 12 40 24 Challenging 5 ++ ++ ++ +++ 24 24 24 50 Toto

I

118 84 118 134

As

option 1 + 3 did score the highest points, the Team hos chosen for this design problem because it is the most challenging one.

The thus chosen design problem had to incorporate the solution to the fact that swallowing chewing gum was not healthy and a solution to the fouling problem within the area of biologically degradabie gum. The Assignment Statement was defined as:

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1.3 Problem introduction

The goal of this section is to outline the different aspects, urgency and magnitude of the problem of the non-environmentally friendly characteristics of conventional chewing gum. The problem can be divided into the aspects of aesthetical pollution and the gravity of pollution. A few examples of governments th at took preventive measures against fouling of chewing gum will be given. The section will cone/ude with the e/eaning efforts and removal costs of disposed chewing gum cuds.

1.3.1 Various problem aspects

Carpets of synthetic rubber on the streets. For the Kalverstraat in Amsterdam, the Lijnbaan in Rotterdam, Hoogh-Catharijne in Utrecht, and all the other public places were people strolI, cye/e, wait and shop, chewing gum is a huge problem. The problem originates from the sixties when chewing gum became increasingly popular in the Netherlands. Explosive growth of chewing gum consumption in 1997 caused the gum cuds on the streets to become a plague (peeters 2003). The consumption of chewing gum in the Netherlands amounts to 4.4 mln. kg chewing gum each year (LEAF 2003). Assumed that half of the amount consumed is disposed on the streets, the gum cuds will cover a surface area equal to 200 football fields each year*.

The fact that disposed gum cuds do not beautify the streets is common sense. But there is a second drawback: once thrown on the street the removal of chewing gum is far from easy. Therefore the problem of disposal of chewing gum cuds on the streets can be divided into two groups:

• Aesthetical: gum cuds on streets and pavements are ugly. This ugliness is partly caused by the sticky character of the cud, which attracts dust and other trash. Besides, this stickiness can also cause pollution to soles, hand bags and other personal belongings.

• Long duration of pollution: chewing gum is not biodegradable and once thrown on the street it will stay there for 25 years. From T able 1.8 the degradation of chewing gum can be compared with other trash. Furthermore, the chewing gum removal is very difficult due to the characteristics of the polymer of which the chewing gum is manufactured.

Table 7.B Degrodation Statistics (Milieudienst Amsterdam 2002)

Type of waste

Degradation in nature

Plastic trays/plastic coffee cups/foam cups Never

Cans 50 years

Leather Max. 50 years

Nylon 40 years

Chewing gum

25 years

Plastic soda PET bottles 10 years

Banana and oronge peels 3 years

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Delft University

of

T echnology, Conceptual Product Design CPD3286

8

1.3.2 Prevention of pollution

Singapore

Countries that banned the use of chewing gum are rare, but Singapore is one of them since 1993. Since chewing gum in Singapore is illegal, chewing in a public place is met with a draconion $1000 fine (approximately 915 EUR) (The Herald 2002).

China

In February 2003 the Chinese government started a project to find new ways of combating chewing gum waste. The Ministry of Science and T echnology hos invited eight institutions to take part in the competition, mysteriously codenamed "863 programme" to find a way to reduce the cost of removing the sticky substance from the country's city streets. The country's 1.3 billion population chews an estimated two billion pieces of gum annually. It is hoped that the winner of the €1 00.000 project wil I develop a lotion over the next 18 months which will effectively dissolve discarded chewing gum left on the ground. In November 2002 Beijing issued a new law that fined public gum-spitters from 20 to 50 Yuan (€2.1 0 to €5.40) (NBC 2003).

1.3.3 Cleaning efforts

Although there are some companies who are subscribed to a chewing gum removal service for the chewing gum in front of their doors, the discouraging magnitudes and high costs cause th at most shops, bars and cinemas have given up the fight. Due to the obstinacy of the plague a company, that should be favourable towards chewing gum due to its America origin, banned chewing gum from its domain: Euro Disney in Paris couldn't cope with the enormous pollution any more (peeters 2003).

1.3.3.1

Cleaning cost

The cost of a cleaning project for chewing gum removal at the Afrikaaner Square (medium size square 58x60m, 3500m2) in Rotterdam were €26,OOO per m2• These costs account for an outdoor project. The cleaning cost for indoor areas (e.g. shopping mails) are double as expensive because alternative methods, such as with liquid nitrogen, have to be used (Jong 2003).

After a week long national holiday in China last year more than 600.000 pieces chewing gum were strewn across Tiananmen Square in Beijing. The ensuing clean-up operation costs were more than € 900.000.

*Consumption of 4.4 mln. kg of chewing gum corresponds with 4 bin. pieces, or 333 mln packages (of 12 pieces). Hansen (2000) assumes th at half of the number of consumed pieces is disposed at the st reet after consumption. This corresponds with 2 bin. pieces. One piece disposed at street covers 5 cm2, 2 bin. pieces

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9

1 .4

Cooperation

1.4.1 Externol

As described in section 1.2, the Design Team created its own assignment for this project. Although the assignment did not originate from on industry initiative, the Design Team welcomed cooperation. Cooperation was welcomed for two reasons. Firstly, because the product to be designed is a radical new concept, it was interesting to exchange ideas and views about the project and the design with companies operating within the field of confectionery and polymers. Second, input from industry was desirabie in order to acquire professional marketing information about the needs

of

consumers concerning chewing gum and information about the chewing gum production process.

In order to get information about Dutch producers of chewing gum, on Internet search was performed. There appeared to be two Dutch companies th at produce chewing gum. Perfetti Van Melle, which hos a production site in Italy for the Mentos Power Gum and RBV LEAF, which produces Sportlife and Xylifresh in Amsterdam.

Perfetti Van Melle is the result of a merger of the Dutch company Van Melle and the Italian company Perfetti in 2001. As the Internet site of Perfetti Van Melle (Perfetti Van Melle 2003) shows strong commitment to environmental issues, this company was contacted first. A few phone calls learned that the company had worked on the research and development of a swallowable protein chewing gum. However, since a few years this research department was terminated and the environmental activities minimalised. Perfetti Van Melle appeared not to be interested in cooperation.

At the same time, RBV LEAF (RBV LEAF) was contacted. RBV LEAF is part of the CSM group (CSM 2003), a food ingredients and confectionary company. The marketing department of RBV was interested in cooperating on the project. In the fifth week of the project a conference was held with a representative of the marketing department and a representative of the R&D department. RBV LEAF was enthusiastic about the chosen design and it was agreed that the Design Team had the freedom to design the product and RBV LEAF would support the design with practical information. This is the reason the process capacity calculations are based on information from RBV LEAF.

In the beginning of the project the Design Team hos been contacted by ATO DLO through on Internet polymer-chat group posting. ATO DLO was interested into applications of polymers for human consumption. Some ideas were exchanged with ATO DLO.

1.4.2 Internol

The Design Team approached project management in the following manner. The Team had weekly meetings every Monday morning to discuss the project progress and any current issues. Chairmanship was rotated every week by a set schedule. Minutes were made of each meeting and placed in a Team map for reference. The team hos also held weekly meetings with the Creativity Coach to discuss project progress and related matters.

At the beginning of the project the Team held a group meeting. This meeting was repeated after 5 weeks with the purpose to evaluate various Team functioning aspects.

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10

The Team did not make use of any task managing programmes because of the fact the Team consisted of only three persons and the work was easy to coordinate. The Team members worked at regular and synchronised hours so all the three Team members followed the progress.

The Team did not divide specialised tasks per member from the beginning of the project. This specialisation was brought in at the end of the project for the writing of the report.

Project planning was approached in two ways. In the beg inning of the project the Team has made an overview of the 12 weeks and hung this planning up in the CPD room so th at everyone could follow the general progress. Each week the Team has made weekly/biweekly detailed planning with task division.

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1 1

2 Applied design method

The goal of this chapter is to provide insight into the design method applied for the design process, give an overview

of

the creative techniques applied by the Design Team and provide a Design-Roadmap for the reading of this report.

2.1 General design method

2.1.1

Choice of procedure

The conceptual design

of

a new product is a design process. Before commencing the design it is necessary to structure the design process. There are several general product design procedures available, such as from Roozenburg and Eekels (Roozenburg and Eekels 1991), used by Frens as mentioned earlier in section 1.1. This design procedure is specifically developed for industrial design and therefore not adequate for chemical product design. There are also guidelines for chemical product design offered by Cussler and Moggridge (2001), but unfortunately they do not offer a practical design ~hodf So there are currently no authoritative and concise guidelines available for performing a chemical roduct design. For this purpose the Design Team has adopted the Chemical Product Design Proceure developed by Korevaar (2003), shown schematically in Figure 2.1 overleaf. The Korevaar design procedure provides a basis for the herein applied method of the various design stages. T is procedure still has to be filled in with design-specific tools and criteria.

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2.1.2

Procedure stages

The procedure applied by the Design Team is a combination of the design procedure developed by Korevaar and the CPD manual by Frens. The Korevaar procedure can roughly be divided into four phases. The four phases refer to the Chemical Product Design manual developed by Frens.

1. Definition ph ase (Ieft column of Figure 2.1)

• Understanding of the Assignment Statement (not depicted in Figure 2.1). • Analysis of Needs of the product to be designed.

• Analysis of Functions of the product to be designed. • Design Problem Definition.

• T echnical translation of defined product functions (not depicted in Figure 2.1) 2. Material and product phase (top middle column of Figure 2.1)

• Generation of ideas and selection of 4 material options as potential product ideas. • Description and composition of selected materials in Basis of Design

• Selection of best material option and definition of the Product Description in Basis of Design

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Delft University of T echnology, Conceptual Product Design CPD3286 12

• Deriving of ingredients for the PVOH chewing gum • Production process

• Availability of basic ingredients 4. Detailed Design

• Target Specifications • Marketing analysis • T echnical feasibility

• Safety health and Environment

• Cost calculations and Economic feasibility

The design trajectory for the Conceptual Product Design ends at the conceptual product design phase of Figure 2.1.

----I~a. Product Need

Need Idertification

Overview Product Design

Launch Product

Figure 2.7: Chemical Product Design Procedure (Korevoor 2003)

2.2 Design tools and creative methads

1 I I

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The Chemical Product Design Procedure supplied by Korevaar requires practical tools for application. The Design Team has developed specific design tools specialised for the design of a chewing gum thot will tackle the Assignment Statement. These tools and creative methods applied by the Team during the different design phases are olso presented in this section.

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2.2.1

Phase 1 : Definitien phase Understanding of the Assignment Statement

The first part of phase 1 is the understanding of the Assignment Statement. This is done in a group discussion.

Analysis of needs of the product to be designed

The second part of phase 1 is the identification of consumer needs concerning the current chewing gum product (NEEDS FROM CONSUMERS) and the assessment of product requirements as defined by the Assignment Statement (REQUIREMENTS FROM THE ASSIGNMENT STATEMENT). An iterative analysis-evaluation procedure developed by Korevaar was adapted for the identification of these two needs areas. An example of an elaborated Need Identification Scheme applied for needs and requirements is shown in paragraph 3.2.1. This method of analysis-evaluation was implicitly applied in all the design steps.

For the consumer need identification (NEEDS FROM CONSUMERS) a questionnaire was held amongst 20 students. The complete questionnaire can be found in Appendix 2.

L

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w

OCIufA.y(

T 0 obtain a list of product requirements as defined by the Assignment Statement (REQUIREMENTS

FROM THE ASSIGNMENT STATEMENT) the Design Team has held a brainstorming session. The addition of these two lists results in the complete product needs list.

Analysis of functions of the product to be designed

The complete list of needs and requirements for the product to be designed is translated into

product functions.

After performing the function analysis an overview was made of knowledge areas already present and knowledge areas still missing by the Design Team. This overview is placed in a Knowledge Map (see section 3.3.1). This Knowledge map is used as guide for project planning and work division and also for awareness of Teams' weaknesses.

Design Problem Definition

The following step of this design phase is the description of the Design Problem Definition. This Definition provides a boundary of the Assignment Statement and the scope within which the solution (product to be designed) has to be situated.

T echnical translation of defined product functions

The last step of phase 1 is the technical translation of product functions for the product to comply with the Design Problem Definition.

2.2.2

Phase 2: Material end preduct phese

Generation of ideas and selection of four material options

Once the technical requirements of the product to be designed are known it is necessary to search for potential product ideas (as stated in Figure 2.1). The potential product ideas in this case are material options th at could possibly fulfil the technical requirements described in the last step of Ph ase 1.

The search for material options was performed by a Team brainstorming session. The brainstorming session was performed with the guidance of the Creativity Coach using the rules of brainstorming.

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14 As

a warming-up for this session the Random Word technique was applied (Infinite Innovations Ltd. 2001). All of the ideas created during the brainstorming session are written on posters that were hung up in the group CPD room allowing space to add new ideas to the list.

The brainstorm ideas have provided the input into the Sieve Selection Scheme. The Sieve Selection Scheme is designed by the Team with a purpose to structure the selection process from the brainstorming session to the final gum base material choice.

The Sieve Selection process can roughly be described by three steps:

Step 1 Selection of material ideas from the brainstorming session and selection of 4 best material options

Description of selected materials in Basis of Design

Step 2 Researching the four material options in the Basis of Design.

The Basis of Design (Chapter 4) is a collection of basic information about the four material options. This information is substantial enough to make a choice between the four options for the best suitable materia!.

Selection of best material option and Product Description in Basis of Design Step 3 Selection of best material option in the Decision Criteria T able

The Selection Criteria T able is a design tooi created by the Team for quantitative evaluation of the four material options. The applied criteria are based on criteria emerging from the Design Problem Definition. Some sustainability criteria such as the SusCon analysis developed by Ditzhuijzen (2001) are also applied in this tabie.

An important design step is the definition of the Product Description. At this point the Team had made use of the TRIZ (The TRIZ Journal 2003) assumption for the ideal problem solution.

The Decision Criteria T able is created by the Team to select the best material option suitable for the Product Description.

2.2.3

Phase 3 Integrated Product Concept

The following step in the design is the development of an Integrated Product Concept (IPC).

Deriving of ingredients for the PVOH chewing gum

The approximate composition of the PVOH chewing gum is derived from the ratios of functional groups in conventional chewing gum. Specific ingredients able to perform these functions are then selected for the PVOH chewing gum.

Production Process

The production process shows the different steps in the production of conventional chewing gum. The production process of the PVOH chewing gum is very similar to this production process. A mind-map has been used for creating an overview of the different stages of the chewing gum production process. With the use of mind-map the Team could obtain an overview of the different production stages and preparation steps.

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15

Availability of basic ingredients

The purpose of this step is to get an overview of availability and the price of the PVOH chewing gum ingredients.

2.2.4 Phase 4 Detailed Design

The Integrated Product Concept is further elaborated into a Detailed Design. T orget Specifications

The first step is the definition of the Target Specifications. T orget Specifications are set for technological performance, marketing and sales.

Marketing analysis

Marketing analysis is on analysis of consumer target group and the placement of the PVOH chewing gum. Also a market analysis is performed by analysing the industry, the latest industry developments, and by a competition analysis. A SWOT analysis is performed for the PVOH chewing gum and a marketing strategy is developed.

T echnical feasibility: Integration of the ingredients described in the IPC

The technical feasibility study is on in-depth study of the technical aspects of the PVOH chewing gum ingredients and their integration.

T echnology window

The different physical stages the PVOH chewing gum goes through during use are described in this section.

Safety health and Environment

The safety of the various PVOH chewing gum ingredients as weil as the consumption safety of the whole product is analysed. A Life Cycle Assessment is performed for the PVOH chewing gum to analyse the environmental aspects of product manufacture, use and disposal.

Cost calculations and Economic feasibility

The last step in the Detail Design is a cost calculation of the designed product, manufacture and overhead. Economic feasibility of the product is analysed.

2.2.5 Other T eam-related aspects

There ore several other creative tools applied by the Design Team that are not particulorly restricted to one particular phase.

The Team applied idea booklets and idea posters during the whole project. Personal notebooks were used for writing down ideas and notes concerning all sorts of issues. Idea posters were hung up in the Team room and used to write down ideas. A blackboard was used for sketching out structure of reports and presentations or visualising relationships.

Mind mapping was applied by the Team for personal learning and clarification of structure.

It is essential for good Team performance to create a good balance between work and relaxation.

For this purpose the Team hos taken walks around the campus after lunch and on afternoon brisk walk. The team hos also taken regular brakes and used these to relax and evaluate the progress.

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At moments when the Team had experienced a setback or 'got stuck' the Team has taken extra care to relax, talk about the problem and look at it from different viewpoints. Sharing ideas between Team members and external contacts has been very valuable.

2.3 Design-Roadmap

The Design Roadmap shown below in Table 2.1 is a guide for finding the various design phases in the report.

0 e eSIgn 00 mop ~

bi

2 1

D .

R

d

Phase , Definition phase Understanding of the Assignment Statement Chapter 1 Analysis of Needs and Functions of the Chapter 3 product to be designed.

Design Problem Definition

Technical translation of defined product functions

Phase 2 Material and Generation of ideas and selection of 4 Chapter 3 product phase material options

Description and composition of selected Chapter 4 materials in Basis of Design

Selection of best material option and Product Description in Basis of Design

Phase 3 Integrated Product Deriving of ingredients for the PVOH Chapter 5 Concept (IPC) chewing gum

Produdion process

Availability of basic ingredients

Phase 4 Detailed Design Target Specifications Chapter 6

Marketing analysis Chapter 7

T echnical feasibility Chapter 8

Safety health and Environment

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17 3 Material options and selection

The goal of th is chapter is to select the four material options that satisfy the needs and fulfil the essential functions of the product to be designed. The chapter starts by identifying the complete needs list that are defined by: needs of consumers concerning the chewing gum, and by the requirements from the Assignment Statement. In the second section the needs are translated into functions and subsequently these functions are defined in terms of technical requirements. The Assignment Statement can then be further specified in the Design Problem Definition. T aking the Design Problem Definition as a starting point, ideas for possible solutions are generated. The four best material options are selected by using the Selection Scheme in the fjnal part of the chapter. These four material options will be further researched in the following chapter Basis of Design.

3.1 Identification of needs

In this section the needs will be defined for the product to be designed according to the Assignment Statement. The Assignment Statement contains three aspects: 'chewing gum', 'not fouling the streets' and 'digestible'. The 'chewing gum' is the product to be designed and this section will start with the identification of the needs for this product. The aspects of 'not fouling the streets' and 'digestible' are requirements placed upon this product and will be discussed in the second part of the section. The specification of needs related to the chewing gum product was performed in an iterative analysis-evaluation procedure for need identification. The Need Identification Scheme shown below describes this process.

3.1 .1

Needs identification scheme

As

described earlier in paragraph 2.2.1, an iterative analysis-evaluation procedure is applied for the identification of product needs from consumers (NEEDS FROM CONSUMERS) and the product requirements as in the Assignment Statement (REQUIREMENTS FROM ASSIGNMENT STATEMENT). An explicit representation of this procedure developed for these two need areas (NEEDS FROM CONSUMERS AND REQUIREMENTS FROM ASSIGNMENT STATEMENT) is represented by Figure 3.1 overleaf.

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Delft University of T echnology, Conceptual Product Design CPD3286 18 Problem definition

• Why do people chew on gum and what is their behaviour when using gum? ... ~t---.,

• Defining the needs of chewing gum in society in addition to the needs of the chewing gum as described in the project description.

• Defining the definition of chewing gum.

• Some needs have to be general. Example: Chewing gum needs to contain certain flavours, and not: chewing gum needs to taste like banana. Other needs have to be specific. Example: In genera I people chew on gum for an x amount of time.

• The needs are consumer based, which means no technical terms are used.

1

Generating Needs Synthesis

How to generate answers to the problem definition?

• Group brainstorm about the needs and behaviour of people chewing gum. Using the TRIZ criterion of

..

the ideal product. ~

• Classifying needs in different area's.

1

Bunch of unspecified needs Analysis

Feasibility analysis and verification of the answers to the problem definition.

• A public poll, with questions based on the different area's generated, with students on the TU Delft as the main target.

• Generating specified needs that cover the problem definition. Do these dear and general answers cover the results from the synthesis? ... t----+__'

• Wh at is the reliability of our poll? ....

Specific Needs

Evaluation

1

•

Do all the generated needs cover the problem definition as stated above? Ranking of the generated needs

(+/-

evaluation).

..

Reporting and classifying the needs so that they can be used for the next step in the product design.

1

Ranked specific needs that cover the Assignment Definition

Translating the ranked specific needs into product properties

Figure

3. 1

Representation

of

analysis-evaluation procedure for the identification

of

needs form consumers and needs from the Assignment Statement

3.1.2 Product needs from consumers

The identification of consumer needs of the chewing gum was performed in a survey taken on a smalI, non-representative population. The complete survey con be found in Appendix 2. The test group consists of 21 persons, largely of Delft Master Chemical Engineering students, and several acquaintances of the Team.

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Findings from the survey are summarised in the T able 3.1 below. The complete results from the questionnaire can be found in Appendix 3.

T able 3. 1 Summary of consumer needs survey findings

• Most people eat between 1 and 5 pieces of gum per week.

• Most people chew on gum between 5 and 30 minutes, fewer people between 30 and 120 minutes.

• Functions of chewing gum in order of importance: fresh breath

tasty

amusement / distraction / stress relief dental care

nutrition or medication not a required function

few people would chew gum for vitamins and to suppress hunger • Reasons for disposing of the chewing gum:

no more taste chewing is not polite not chewable any more

• Medium price of a pocket of 12 pieces of gum should lie between 0,5 and 1 EUR. It is a genera I feeling that most people do not precisely know how much they pay for a packet of gum.

• Most important reasons for not swallowing gum is the perception that it is disgusting and unhealthy.

Mr.Cobelens from LEAF RBV confjrmed most of the findings from this survey. Concerning the taste retention Mr. Cobelens stated that the chewing gum should retain its f1avour for approximately 15 minutes. Therefore the chewing gum should be chewable for at least these 15 minutes.

3.1.3 Product requirements from Assignment Statement

In addition to th is list that defines the consumer needs for the product, the product requirements from the Assignment Statement will be added.

The first requirement: not fouling the streets. This can be achieved in two ways. Either the chewing gum should not be thrown on the street, or if thrown on the street, it should not cause permanent fouling. As the Assignment Statement is focused on the design of a chewing gum, the removal of gum cuds already disposed on the streets will not be taken into account.

Prevention of chewing gum being thrown on the street can be achieved in various ways, e.g. fees, packaging, commercials or by changing the characteristics of the chewing gum. However, the Assignment Statement is focused on the design

of

the chewing gum, so the focus will be on changing the characteristics of the chewing gum. The easiest way of ensuring that the chewing gum wil I not be thrown on the st reet is by making sure people will not take it out of their mouth, but simply swallow it. As the ease of swallowing is c10sely related to the digestibility, this aspect will be discussed together with digestibility.

Prevention of the disposed chewing gum to cause permanent fouling can be achieved by making the chewing gum more easily removable from the street or by making it degradabie. By degradabie one of the following is meant:

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20

• Biodegradation: degradation of the chewing gum is mediated at least partially by a

biological system

• Erosion: chewing gum is worn away from the surface of the street pavement

These various ways of degradation imply that chewing gum material can still find its way into the environment. The first requirement of the Assignment Statement also applies to the chewing gum waste. This implies th at the waste material should not cause environmental fouling.

The second requirement: digestible. The definition of 'digest' according to the Mirriam-Webster dictionary is: "To convert (food) into absorbable form". This definition of 'digestible' will be adjusted to the aim of this project.

The problem with the Webster definition is th at almost everything we eat is only partially digested (and partially excreted) by the human body. Because of this, the term flat least partially" will be added to the requirement of absorbability. The second addition will be that the components, if absorbed by the body, should not have any adverse effe cts on the human body. Finally, one other addition has to be done. Because the new product should not only be digestible, but also be attractive to ingest, digestibility also implies a psychological aspect of swallowing, which can be influenced by making the chewing gum (become) smaller in the mouth. This way it would not remain 'one large indigestible lump' in the digestive system. In summary, the work-definition of 'digestible' is:

"Stimulating ingestion through smal/er size, at least partial/y absorbed by the human body and no

adverse effects on the human body".

Remains of human digestion will be excreted into the municipal sewage treatment system. Any chewing gum remains should also be metabolised by sewage-treatment bacteria.

3.1.4 Complete product needs

Addition of the product needs from consumers and the product requirements form the Assignment Statement produces the complete product needs list. The needs within this list are not ranked at this point, because these needs are of equal importance for the three areas of the Assignment Statement (chewing gum, no street fouling and digestible).

A. No street fouling B. Digestible

C.

T asty (good taste, freshening)

D. Taste retention (minimum of QJ>h)

D. S

E. Chewability (minimum of Oy,Eh) 7 amusement, distraction and stress-relief F. Storage life (minimum of 1 year)

G. No dental damage

H. Appealing: form, size, special attention for outside layer

I.

Price (maximum €1 b -)

l.

-In addition to this list of needs, there are some needs th at are not necessary but can be of additional value:

J.

Extra functions (dental care, vitamins, energy, anti-hunger, medical) K. Handy packaging

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3.2 Function analysis

The goal of th is section is to provide a complete list of functions that the product to be designed needs to contain. Furthermore, conventional chewing gum will be analysed in order to define the components th at fulfil these essential functions. Once it is clear which components fulfil which essential functions, the functions can be described in technical terms.

3.2.1 List of functions

The needs identified in the previous section have to be translated into product functions. Some of the defjned needs have to be grouped or split up in order to assign the appropriate functions.

For example, taste and taste retention con be translated into flavour, freshening and distribution.

Elasticity, smoothness, resinous feeling and chewing 9um hardness together determine the chewability. \-

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A.

No street fouling: easy removable or degradabie (water soluble, biodegradable or degradation byerosion).

B. Digestible: the chewing gum should at least partially be digestible. It should not contain any toxic substances, and none of those should come free during chewing or digestion.

C.

Flavour:

- Combination of different flavours - Amount of flavours

- Mixture of oils (volatility)

- Retention for at least 15 minutes D. Freshening:

- Cold / fresh mouth

- Treating bad breath (sulphur neutralising substances) - Retention for at least 15 minutes

E. Elasticity F. Smoothness G. Resinous feeling H. Hardness

I.

Compound stability (for period of at least 12 months)

J.

No dental damaging substances (sugor free) K. Appealing form, size and outside layer

L.

Price (maximum €1, -)

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Optional additional functions:

M. Functional substances, (e.g.):

- Dental care - Medical - Vitamins - Energy

Hunger-suppression

N. Package (biodegradable material preferably)

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3.2.2 Components thot fulfil

essentie

I

functions

Conventional chewing gum is composed for about 30% to 40% of a water insoluble masticatory part that is called the gum base. The remaining part of the chewing gum consists of sweeteners, flavour and other additional ingredients.

3.2.2.7 Fundions list: C

to

L

The needs for the product to be designed are represented by the functions C through L in the above given functions list (A to L). The gum base executes the function of 'elasticity', 'smoothness', 'resinous feeling' and 'hardness'. The functions of 'flavouring', 'freshening', 'compound stability', 'no dental damaging substances' and 'appearance' are performed by the sweeteners, flavouring agents and other ingredients. The price will be dependent on the cost of all the ingredients present in the chewing gum.

Due to the water insoluble characteristic of the gum base and the water-soluble characteristic of the other ingredients, the gum base solely remains after usage. The gum base th at remains after usage is called the 'gum cud'. Due to its formulation, this gum base has an adhesive like characteristic. The previously chewed gum cuds can stick to surfaces, which they happen to come in contact with, are very hard to remove and are indigestible. Improper disposal of these gum cuds on the streets creates the known fouling issues and high removal costs as was mentioned in section 1.3.

In order to Iocate the substances making this gum cud sticky and hard to remove, a screening has to be performed on the ingredients of the conventional chewing gum.

3.2.2.2 Ingredients

of

conventional chewing gum

Conventional gum bases consist out of natural masticatory substances of vegetable origin such as:

chicle, jelutong, sorba and natural rubber. Synthetic rubbers and elastomers like polyvinyl acetate and the butadiene-styrene copolymer are also used in a gum base. Different waxes and resins are used as an oleaginous plasticizer for the gum base. Furthermore the gum base contains other plasticizing agents like glycerine that are used to maintain the soft texture.

Wetting agents aid the user in moistening the chewing gum for mastication. Emulsifiers in the chewing gum are used to maintain good mixing of the ingredients. Thickeners provide body, texture and physical compactness to the chewing gum.

The flavours used in chewing gum are usually mixes of different oi! essences like mint, menthol, spearmint, wintergreen, cinnamon, peppermint, lemon, orange, grape and lime. Chewing gum can also contain breath freshener substances th at neutralise the malodorous breath in its roots by neutralising substances that cause bad breath. The conventional chewing gum also contains preservatives.

Colouring agents are used to improve the overall attractiveness of the food. Fillers or bulking agents are used to add bulk to the products. Last but not least a conventional chewing gum contains a large amount of sweeteners.

3.2.2.3 Fundions

A

and

B

The restrictions to the product to be designed are represented by the functions A and B. As mentioned above the restrictions of 'no street fouling' and 'digestible' will be mainly influenced by the chewing gum base.

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It con be concluded that the gum base influences the most important functions of the chewing gum. It is assumed th at the functions of 'flavouring', 'freshening', 'compound stability', 'no dental damaging substances' and 'appearance' th at are performed by the sweeteners, flavouring

agent

~

and other ingredients con be kept the same as in conventional chewing gum. For this, the technical description of the functions will be mainly focused on the gum base. Due to functions the gum base

hos to exhibit, it hos to contain a polymer (Iike) material.

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3.2.3 Technical description of functions

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The functions that are defined in the previous section have to be translated into technical

r~

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requirements. In this section, the main functions of the product will be defined in technical terms.

3.2.3.1 No

street fou/ing: once thrown

on

the street not causing permanent fouling

As described in the previous §3.1.3 prevention of the disposed chewing gum to cause permanent fouling con be achieved in four ways: making the chewing gum more easily removable from the st reet, biodegradable, water-soluble or degradable byerosion. In the following the criteria for those ways of prevention of street fouling by chewing gum are described.

A.

Easy removal from street

Making a gum cud more easily removable from the street con be achieved by reducing adhesion of the chewing gum. Adhesion con be defined as: 'the state in which two surfaces are held together by interfacial forces of attraction, owing to the interaction of molecules, atoms and ions in the two surfaces' (Mark et al. 1985).

In the case of chewing gum mechanical interlocking and Van der Waals attractions cause the adhesion to the street. The Van der Waals forces between the chewing gum and the street will always exist. The best way to prevent stickiness is to make sure the gum hos poor wetting characteristics when disposed on the street.

The presence of a low Mw fraction (30.000 - 100.000

M

_{n )}provides a good wetting of the surface (quick stick), whereas the high molecular weight fraction provides cohesive strength. This is especially the case when rubber flows easily at low stresses but hardens at high strain (because it crystallises) like natural rubber does. The flow characteristics of a chewing gum are dependent on the location of the glass transition temperoture and on the rheology characteristics.

In order for the polymer to be in the rubber state when chewed, it should have a glass transition temperoture below the temperoture of the mouth (37°C). Preferably, in respect to street fouling prevention, just below the temperature of the mouth so that the gum cud enters the glass state when thrown on the street.

Tg depends on the following polymer characteristics: • Polymers with flexible backbone chains have high Tg.

• Polymers containing -CH2CH2-, -CH20CHr or -SiOSi- links have accordingly low values of Tg.

• For high Mw polymers, Tg is essentially independent of Mw, but as the polymer chain length becomes shorter the Tg is likely to decrease appreciably.

• For random copolymers and compatible polymer blends, only a single Tg, usually Iying intermediate between the Tg of the corresponding pure homopolymers, is observed.

Therefore, the required characteristic of the material if it is to become hard after removal from the mouth is: