Praca oryginalna Original paper
In Poland, pork proves to be the most popular meat
for consumption (8), which provides significant levels
of the dietary saturated fatty acids in humans (13).
Animal fat, especially its fatty acid content and
chole-sterol is considered the main cause of coronary heart
disease in humans (5). Fatty acid deposition in pig fats
largely reflects dietary fatty acid composition. Thus it
is of primary importance to supply animals feeds of
well-balanced fatty acids profile and especially the
appropriate saturated/unsaturated acids ratio. Grass pea
oil shows a fairly high unsaturated fatty acids level,
i.e. 18.6% C18:1, 38.9% C18:2, 8.0% C18:3 of total
fatty acids (7). The composition of the fatty acids
contained in the seeds of grass pea, and especially the
proportion of saturated and unsaturated acids, are
the cause of this fat being highly dietetic, similar to
soybean oil in its usability (7).
The objective of the study was to determine the
influence of raw and processed grass pea seeds, at
different inclusion levels, on the fatty acids profile and
sensory characteristics of the following pork muscles
the M. adductor and M. longissimus dorsi.
Material and methods
The experiment was conducted on (Polish Landrace × Polish Large White) × Pietrain pigs, from 25 kg up to ca 100 kg body weight (BW). The pigs were slaughtered at approximately 100 kg body weight.
One hundred and twenty piglets were assigned to five feeding groups. The animals were placed in pens, with two animals located to each pen. Feed and water were provided ad libitum. The pigs were fed according to Pig Feeding Norm (1993). The experimental factors were sources of legume seeds protein, i.e. raw or extrusion-cooked grass pea seeds, soybean meal and rapeseed meal 00. The animals of group I were fed standard grower (30-70 kg of body weight) and finisher (70-110 kg of body weight) mixtures (tab. 1). In the experimental formulas, soybean
Influence of grass pea seeds in pig diets on the fatty
acid composition and sensory attributes of pork
ANNA WINIARSKA-MIECZAN
Institute of Animal Nutrition, Faculty of Biology and Animal Breeding, University of Life Sciences, Akademicka 13, 20-950 Lublin, Poland
Winiarska-Mieczan A.
Influence of grass pea seeds in pig diets on the fatty acid composition and sensory attributes of pork
SummaryThe objective of the study was to determine the effect of the amount of raw or extruded grass pea seeds as a substitute for soybean and rapeseed meals in the diet of pigs, as well as the effect on the fatty acid composition and sensory characteristics of pork meat. The experiment was carried out on 120 fatteners (Polish Landrace × Polish Large White) × Pietrain breeds, in 5 feeding groups. The animals were fed mixtures containing raw or extrusion-cooked grass pea (Lathyrus sativus L.) seeds, substituting soybean and rapeseed meal completely or partly. The fatty acid profile of the experimental diets and the meat samples was determined by gas chromatography. Sensory analysis of M. adductor and M. longissimus dorsi following the thermal processing (cooking and roasting) was performed according to Bary³ko-Pikielna. A five-point scale was used for the sensory quality assessment, which included juiciness, tenderness, odour (intensity and desirability) and taste (intensity and desirability). Diets with a raw grass pea seeds as the only source of protein promoted an increase in the miristic acid level in the M. adductor and M. longissimus dorsi of the pigs. The use of diets containing raw or extruded grass pea seeds (50 or 100% of protein) resulted in a decrease (P £ 0.05) in the linoleic acid level in the adductor muscle. No effect of processing (i.e. raw or extrusion--cooked grass pea seeds) was recorded on the total saturated, monounsaturated and polyunsaturated fatty acids level in the studied tissues. No significant influence (P £ 0.05) of the experimental diets on the sensory characteristics of the adductor and longissimus dorsi muscles. Therefore, it may be concluded that raw or extrusion-cooked grass pea seeds do not negatively influence pork quality.
Keywords: Lathyrus sativus, grower-finisher pig, m. adductor, m. longissimus dorsi, fatty acid, sensory analysis
meal and rapeseed meal were replaced by raw or extru-sion-cooked grass pea seeds. In groups II and III, raw grass pea seeds were fed throughout the whole experimental period at the level of 50% and 100% of legume seeds protein, respectively. In group IV, extrusion-cooked grass pea seeds were used (50% legume seeds protein); in group V, protein feed was entirely exchanged for extrusion-cooked grass pea seeds.
Carcass slaughter evaluation was performed in accord-ance with the methods used at Polish Pig Testing Stations (SKURTCh) as described by Ró¿ycki (12). After slaughter meat samples (weighing about 600 g) were taken from the
M. longissimus dorsi in the area of the last thoracic and the first lumbar vertebra as well as from the M. adductor.
The content of nutrients in mixtures was determined with standard AOAC methods (1). The fatty acids profile of the feed and meat samples was determined by the gas chromato-graphy method described by Rotenberg and Anderson (11), using INCO 505 M apparatus with TZ 4620 integrator, made by the Czech firm Laboratorni Pristroje Praha. The identi-fication was made in conformance to the standards of Applied Science Laboratories. All the results obtained from the analytical laboratory were performed in three replica-tions.
Tab. 1. Ingredients and chemical composition of the control and experimental diets
Explanations: * composition of premix/kg: vitamin A 400 000 IU, vitamin D3 66 000 IU, vitamin E (as DL-á-tocopherol acetate) 6000 mg, vitamin K3 (as menadion sodium bisulfite) 100 mg, vitamin B1 60 mg, vitamin B2 150 mg, vitamin B6 100 mg, vitamin B12 1 mg, nicotinic acid 800 mg, pantothenic acid (as Ca-D-pantothenate) 350 mg, folic acid 15 mg, choline 10 000 mg, betaine 3500 mg, Fe 350 mg, Zn 3650 mg, Mn 3000 mg, Cu 3500 mg, J 75 mg, Co 15 mg, Se 13 mg; ** trypsin inhibitor activities
) % ( s t n e i d e r g n I s p u o r g g n i d e e F I II III IV V r e w o r g ifnisher grower ifnisher grower ifnisher grower ifnisher grower ifnisher t a e h W 35.00 31.50 37.40 31.00 30.00 31.50 37.40 31.00 30.00 31.50 y e lr a B 45.55 54.60 33.50 49.03 35.75 44.76 33.50 49.03 35.75 44.76 w a r a e p s s a r G 15.00 10.00 30.00 20.00 d e d u rt x e a e p s s a r G 15.00 10.00 30.00 20.00 l a e m n a e b y o S 13.00 8.00 10.00 7.20 10.00 17.20 0 0 l a e m d e e s e p a R 2.00 l a e m e n o b -d n a -t a e M 5.00 2.00 1.50 1.00 1.00 1.50 1.00 1.00 * x i m e r P 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 e n i s y l-L 0.05 0.06 0.15 0.15 0.40 0.26 0.15 0.15 0.40 0.26 e n i n o i h t e m -L D 0.05 0.02 0.15 0.08 0.05 0.02 0.15 0.08 tl a s r e d d o F 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 e n o t s e m i L 0.10 0.54 0.50 0.80 0.50 0.60 0.50 0.80 0.50 0.60 e t a h p s o h p m u i c l a c i D 0.60 0.50 0.90 0.50 0.60 0.50 0.90 0.50 : s n i a t n o c s e r u t x i m d e e f g k 1 g , n i e t o r p e d u r C 176.701 151.301 178.001 151.901 171.501 152.601 180.501 153.801 174.001 155.001 g ,t a f e d u r C 24.17 21.82 18.98 18.54 16.73 18.22 18.91 18.49 16.58 18.12 g , e n i s y L 19.21 17.54 19.08 17.59 19.26 17.52 19.06 17.52 19.20 17.44 g , e n i e t s y c + e n i n o i h t e M 15.67 15.21 15.56 14.95 15.53 14.90 15.55 14.92 15.51 14.90 g , s d i c a y tt a F x x Myirsitc(14:0) 10.32 10.25 10.36 10.35 10.38 10.33 10.41 10.29 10.38 10.39 x x Palmiitc(16:0) 14.36 14.68 15.03 15.44 16.58 16.25 15.87 15.95 17.69 16.44 x x Steairc(18:0) 10.98 10.95 11.75 11.44 12.64 12.08 11.99 11.56 12.94 12.15 x x Oleic(18:1n-9) 13.88 13.79 15.68 15.19 17.68 16.78 16.09 15.01 18.35 16.64 x x Linoleic(18:2n-6) 13.45 14.56 18.89 19.11 26.99 27.98 19.35 17.88 26.90 22.48 x x Linolenic(18:3n-3) 11.21 13.14 19.34 12.65 10.89 12.32 19.12 12.34 10.75 11.89 g m , U I T 1** 10.03 10.02 13.07 12.09 16.12 14.14 10.10 10.05 10.20 10.09 b-ODAP,µg 10.00 10.00 10.19 10.10 10.04 10.21 10.10 10.05 10.19 10.11
The sensory assessment of M. adductor and M. lon-gissimus dorsi after thermal processing (cooking and/or roasting) was made according to Bary³ko-Pikielna (2). The moiety of samples of about 200 g weight were cooked for 5 min in a 0.6% NaCl solution at 76°C, at a 1 : 2 meat/water ratio. Other samples were roasted at 150-160°C under a gas roaster for 4 min. The samples were scored for juici-ness, tenderjuici-ness, odour (intensity and desirability) and taste (intensity and desirability) on a five-point scale: from 1 point (minimum) up to 5 point scores (maximum). Inten-sity ranged from 1 point (very slight) to 5 points (very strong) and similarly for desirability, from 1 point
(undesi-rable) up to 5 points (very much desi(undesi-rable). The analysis was carried out by a trained panel of 10 people, characte-rized by higher than average sensory sensitivity.
The results obtained were analysed statistically (stan-dard error of means SEM, stan(stan-dard deviation sd and effects of diet) by ANOVA and analysis of variance with Duncans multiple range test, using Statistica 6.0 software. The P value £ 0.05 was considered significant.
Results and discussion
Table 2 presents a fatty acids profile in the fat of
M. adductor samples. It was found that the M. adductor
Tab. 2. The influence of raw and extruded grass pea seeds on the fatty acid profile of M. adductor and M. longissimus dorsi (mean ± sd) )l a t o t f o % ( s d i c a y tt a F Feedinggroups SEM Effectsofdiet I II III IV V r o t c u d d a . M ) 0 : 4 1 ( c it s ir y M 1.68a±0.2 1.72a±0.1 1.83b±0.1 1.72a±0.1 1.66a±0.1 0.02 * ) 0 : 6 1 ( c it i m l a P 24.92±2.1 25.20±0.9 25.18±2.0 25.00±1.7 25.17±1.1 0.29 ns ) 7 -n 1 : 6 1 ( c i e l o ti m l a P 3.05±0.3 3.07±0.03 3.00±0.2 3.00±0.2 3.03±0.4 0.02 ns ) 0 : 8 1 ( c ir a e t S 13.07±2.0 12.97±1.1 12.92±1.2 13.02±1.1 13.00±1.0 0.20 ns ) 9 -n 1 : 8 1 ( c i e l O 45.80±2.8 45.79±4.5 45.51±3.8 45.71±2.7 45.52±4.0 0.32 ns ) 6 -n 2 : 8 1 ( c i e l o n i L 9.35b±0.9 9.12a±0.9 9.20a±1.4 9.15a±1.2 9.28ab±0.9 0.13 * ) 3 -n 3 : 8 1 ( c i n e l o n i L 0.60±0.02 0.55±0.03 0.63±0.03 0.63±0.04 0.58±0.08 0.01 ns ) 9 -n 1 : 0 2 ( c i o n e s o c i E 1.53a±0.1 1.58a±0.1 1.73b±0.1 1.75b±0.2 1.76b±0.3 0.03 * Sfattyacids d e t a r u t a s 39.67 39.89 39.93 39.74 39.83 0.29 ns d e t a r u t a s n u o n o m 50.38 50.44 50.24 50.46 50.31 0.14 ns d e t a r u t a s n u y l o p 9.95b 9.67a 9.83ab 9.80ab 9.86ab 0.03 * A F S / A F U P 0.25 0.24 0.25 0.25 0.25 0.02 ns 3 : 8 1 C / 2 : 8 1 C 15.58 16.58 14.60 14.52 16.00 0.26 ns i s r o d s u m i s s i g n o l . M ) 0 : 4 1 ( c it s ir y M 1.77a±0.1 1.73a±0.1 1.92b±0.2 1.77a±0.1 1.81a±0.1 0.04 * ) 0 : 6 1 ( c it i m l a P 25.02±2.0 24.62±2.3 25.20±2.0 24.83±1.9 24.88±2.2 0.25 ns ) 7 -n 1 : 6 1 ( c i e l o ti m l a P 3.22±0.1 3.27±0.04 3.23±0.09 3.30±0.1 3.27±0.09 0.05 ns ) 0 : 8 1 ( c ir a e t S 13.50±1.0 13.45±1.2 13.91±1.2 13.54±0.9 13.20±1.0 0.15 ns ) 9 -n 1 : 8 1 ( c i e l O 46.28±3.9 46.74±4.0 45.52±3.5 46.28±2.7 46.58±4.1 0.46 ns ) 6 -n 2 : 8 1 ( c i e l o n i L 8.59±0.8 8.58±1.0 8.55±0.3 8.62±0.2 8.62±0.9 0.17 ns ) 3 -n 3 : 8 1 ( c i n e l o n i L 0.41±0.01 0.37±0.01 0.40±0.02 0.37±0.01 0.37±0.01 0.01 ns ) 9 -n 1 : 0 2 ( c i o n e s o c i E 1.21±0.09 1.24±0.1 1.27±0.04 1.29±0.04 1.27±0.08 0.01 ns Sfattyacids d e t a r u t a s 40.29 39.80 41.03 40.14 39.89 0.29 ns d e t a r u t a s n u o n o m 50.71 51.25 50.02 50.87 51.12 0.37 ns d e t a r u t a s n u y l o p 19.00 18.95 18.95 18.99 18.99 0.08 ns A F S / A F U P 10.22 10.22 10.22 10.22 10.23 0.03 ns 3 : 8 1 C / 2 : 8 1 C 20.95 23.19 21.38 23.30 23.30 0.31 ns
Explanations: ns non significant; * P £ 0.05; a, b means in the same row with different superscripts differ significantly (P £ 0.01); PUFA polyunsaturated fatty acids; SFA saturated fatty acids
fat in the animals supplied with a mixture of raw grass
pea seeds at 50% of legume seeds protein (group II)
contained significantly (P £ 0.05) less linoleic acid
(C18:2) compared to the samples obtained from the
control group. Similar effects were observed in the
other experimental groups. Doubling a seeds share in
a mixture dose (group III) resulted in an increase in
a myristic acid (C14:0) level by almost 9% compared
with group I. Moreover, an increase of eicosenoic acid
(C20:1) concentration by more than 13% was
recor-ded in the animals from the same group compared to
the control. In the adductor muscle fat of the pigs from
group III (raw grass pea seeds 100% of legume seeds),
IV (extrusion-cooked grass pea seeds 50% of legume
seeds protein) and V (extrusion-cooked grass pea
seeds 100% of legume seeds) a rise of eicosenoic acid
(C20:1) content up to that of group III was noted.
The fatty acids profile of M. longissimus dorsi fat is
presented in table 2. There was no effect of the
intro-duction of a mixture with raw grass pea seeds at 50%
dietary protein (group II) or extrusion-cooked seeds
on the examined parameters. At the same time, it was
stated that the application of a mixture containing
raw grass pea seeds at 100% of the protein induced
a significant increase of a myristic acid profile in the
longissimus muscle, compared to the control (1.92
vs. 1.77%).
No effect of grass pea seeds addition to pig
mixtu-res on fatty acids profile in the meat was observed.
The studies by Winiarska-Mieczan (14) indicated that
using raw or extrusion-cooked grass pea seeds
substi-tuted for soybean and rapeseed meals in the mixtures
for pigs did not result in any significant changes in
a fatty acids profile of pig backfat. To a large extent,
the proportion of fatty acids in animal tissues is a
re-flection of their content in feeds (9). However,
Leska-nich et al. (10) noted no significant effect of a dietary
fat content on total lipid contents in pork.
Table 3 gives the results of the sensory evaluation
of M. adductor and M. longissimus dorsi after cooking
or roasting. Juiciness, tenderness, odour (intensity and
desirability) and taste (intensity and desirability) were
established. No significant effect of diet on the
senso-ry characteristics of the muscles was observed.
There-fore, it may be concluded that raw or
extrusion--cooked grass pea seeds do not negatively influence
the quality of meat, compared to soybean meal.
The flavour of meat is one the most important
factors in determining consumer acceptability. The
characteristic flavour is determined, however, by the
proportions of saturated fatty acids in the fat and the
unsaturated fatty acids, aldehydes, ketone
hydrocar-bons and alcohols that contribute to the pork flavour
development. Over the fatty acids break-down process
a high number of volatile products is released, such
as aldehydes, that indirectly affect the flavour when
involved in the Maillard reaction (6). Breed, sex and
nutrition also influence the meat flavour (5). The aim
Tab. 3. Sensory characteristic of adductor and longissimus dorsi muscles (points: 1 minimum, 5 maximum)
c it s ir e t c a r a h C s p u o r g g n i d e e F M E S Eofffedcietst s p u o r g g n i d e e F M E S Eofffedcietst I II III IV V I II III IV V g n i k o o C Roasitng r o t c u d d a . M s e n i c i u J 4.74 4.71 4.73 4.71 4.75 1.04 ns 4.68 4.75 4.70 4.72 4.69 0.26 ns s s e n r e d n e T 4.36 4.38 4.35 4.35 4.35 0.12 ns 4.55 4.54 4.49 4.51 4.50 0.08 ns r u o d O x x Intenstiy 4.58 4.61 4.61 4.57 4.62 1.03 ns 4.87 4.85 4.86 4.84 4.85 1.02 ns x x Desriablitiy 4.61 4.60 4.57 4.57 4.59 0.95 ns 4.46 4.48 4.51 4.50 4.49 0.02 ns e t s a T x x Intenstiy 4.35 4.38 4.34 4.39 4.36 0.10 ns 4.36 4.35 4.38 4.35 4.37 0.08 ns x x Desriablitiy 4.51 4.50 4.51 4.49 4.50 0.08 ns 4.39 4.40 4.39 4.41 4.42 0.12 ns i s r o d s u m i s s i g n o l . M s e n i c i u J 4.60 4.63 4.65 4.67 4.65 0.12 ns 4.71 4.68 4.69 4.71 4.71 0.14 ns s s e n r e d n e T 4.32 4.27 4.27 4.27 4.30 0.09 ns 4.32 4.33 4.32 4.35 4.30 0.02 ns r u o d O x x Intenstiy 4.51 4.53 4.42 4.37 4.53 1.01 ns 4.69 4.65 4.64 4.70 4.70 0.10 ns x x Desriablitiy 4.55 4.68 4.48 4.43 4.72 0.54 ns 4.51 4.52 4.48 4.46 4.50 2.15 ns e t s a T x x Intenstiy 4.52 4.47 4.48 4.52 4.47 0.08 ns 4.36 4.36 4.38 4.35 4.33 1.02 ns x x Desriablitiy 4.67 4.48 4.68 4.46 4.45 0.54 ns 4.27 4.29 4.25 4.23 4.23 0.22 ns
of the culinary meat-aging process is to obtain the
ap-propriate sensory properties (3).
Conclusions
The use of raw or extrusion-cooked grass pea seeds
substituting for soybean and rapeseed meals in the diets
for pigs did not induce any significant changes in the
fatty acid profile and sensory properties of the
adduc-tor and longissimus dorsi muscles. It is noteworthy
that with respect to meat quality and acceptability it
has the potential to be used as a low production cost
substitute for soybean meal and rapeseed meal.
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Authors address: dr Anna Winiarska-Mieczan, Akademicka 13, 20-935 Lublin; e-mail: amieczan@poczta.onet.pl
