• Food Science of Animal Resources
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• v.31 no.1
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• pp.100-106
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• 2011

The physicochemical characteristics of chicken breast were determined to identify the optimal ratio of $CO_2$ and $N_2$ to maintain chicken breast quality during cold storage for 6 d. The mixing ratios of $CO_2$ and $N_2$ were 20:80, 40:60, 60:40, and 80:20, respectively. The pH of the chicken breast packed with 80% $CO_2$ and 20% $N_2$ was lower than that of the control on day 1 (p<0.05). The lightness ($L^*$) of the breast increased with increasing $CO_2$ during storage (p<0.05), whereas no difference was found for redness ($a^*$) and yellowness ($b^*$). A lower volatile basic nitrogen level was found for chicken breasts exposed to higher $CO_2$ levels. Furthermore, lipid oxidation of the chicken breast packed with $CO_2$ decreased with increasing $CO_2$ level, and 40% $CO_2$ significantly reduced 2-thiobarbituric acid reactive substances (TBARS) values on days 1 and 6. The total number of microbes was reduced in chicken breast exposed to more than 40% $CO_2$ during storage days 3 and 6 (p<0.05); however, Escherichia coli was not affected by $CO_2$ level. Coliforms of chicken breast were reduced in the 40% $CO_2$ level on storage day 3. Moreover, tray-packed chicken breast exposed to 40% $CO_2$ did not collapse. These results suggest that 40% $CO_2$ and 60% $N_2$ were the optimal conditions for packaging chicken breasts during cold storage.

• Food Science of Animal Resources
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• v.32 no.6
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• pp.820-827
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• 2012

This study was performed to evaluate the effect of yam (Diocorea japonica) extract by methanol on sausage quality during cold storage. Yam extracts were prepared by 70% methanol and concentrated using rotary evaporation. The total phenol contents of the extracts were 123.03 mg/g. 1,1'-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity and super oxide dismutase (SOD) activity of the extracts were increased with dose dependently. Nitrite scavenging activity was also increased with the increase of concentration of yam extracts; in particular, 70 ${\mu}g/mL$ of the extracts showed 57.12% of nitrite scavenging activity. Sausages containing yam extracts showed lower pH than that of the control. In color, the lightness ($L^*$) of sausages with 1.0% of the yam extracts was lower than that of the control. Redness and yellowness of the sausages with 1.0% of the yam extracts were higher than those of the control. Thiobarbituric acid reactive substances (TBARS) value of the sausage with 1.0% of the extracts was lower than those of the control on days 9 and 12. However, the hardness of the sausage was increased with an increase in yam extracts. From these results, the yam extracts showed high antioxidant activity; moreover, it also retards the lipid oxidation of the sausages during cold storage. The yam extracts could be used as additives to prevent lipid oxidation of the sausage. Further study should be conducted in order to identify the optimum concentration of the extracts in meat products.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.53-59
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• 2007

This study was conducted to determine the effects of dietary supplementation with probiotics on the growth and meat quality of finishing pigs. A total of forty eight ($Landrace{\times}Yorkshire{\times}Duroc$) pigs ($55.3{\pm}1.5 kg$ average initial body weight) were randomly assigned to four groups and fed on a diet supplemented with 0, 0.2, 0.5 or 1% probiotics for 58 days. The pigs were slaughtered at approximately 105 kg live weight. Supplementation with 0.2% probiotics significantly (p<0.05) increased daily gain compared to the control. The daily gain of pigs in the 0.2% probiotic group was 0.95 kg whereas that of the control was 0.85 kg. The average feed intake was 2.79-2.84 kg and there were no significant differences in feed intake between the control and test groups. The feed conversion of the 0.2% probiotic group was 2.96 kg whereas the control showed a feed conversion of 3.28 kg. The results of this study imply that supplementation with 0.2% probiotics may improve the feed conversion of pigs. There were significant differences in carcass weight, carcass ratio, backfat thickness, and frequency percentage of A grade carcasses between the control and probiotic test groups. In addition, the moisture, crude protein and crude ash contents of the probiotic treated groups did not differ significantly from the control group, however the crude fat values of the 0.2% probiotic test group was significantly tower than the other groups. The muscle pH levels of all samples ranged from 5.63-5.67 which is the normal pH of pork. The supplementation of probiotics resulted in decreased lightness ($L^*$) values and increased redness ($a^*$) values. Furthermore, the saturated fatty acid contents of the 0.2% and 0.5% probiotic test groups decreased and the unsaturated fatty acid contents increased relative to the control.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.29-34
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• 2007

We investigated the properties of pork jerky prepared under various drying conditions. Drying conditions were control ($80^{\circ}C$/210 min), T1 ($55^{\circ}C/60 min\to65^{\circ}C/60 min\to72^{\circ}C/90 min$), and T2 ($72^{\circ}C/90 min\to65^{\circ}C/60 min\to55^{\circ}C/60 min$), respectively. Water content and water activity ($a_w$) were the lowest in control, while TBA values were the highest among all groups (p<0.05). CIE $L^*$-value in T1 was significantly (p<0.05) lower than in T2 and CIE $a^*$-value showed significantly (p<0.05) the highest in control. CIE $b^*$-value in T2 were significantly higher (p<0.05) compared to the other treatments. Drying yields of pork jerky showed the lowest values in controls but highest in T2 jerky. In textual profile evaluations, control samples had greater hardness, cohesiveness, gumminess, and chewiness values than the other treatments, but springiness values were the lowest (p<0.05). Controls had significantly (p<0.05) lower scores than the other treatments in all sensorial traits. Total bacterial counts in T2 were the lowest during drying process. Based on our findings, we conclude that T2 conditions provided the most effective drying process.

• Korean Journal of Poultry Science
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• v.38 no.2
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• pp.129-136
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• 2011

The objective of this study was to evaluate the effects of different levels of ${\alpha}$-tocopherol and selenium in broiler diets on performance and physicochemical properties of chicken thigh meat. A total of 360 broiler chicks divided into six groups were fed a basal diet (control) or basal diet supplemented with 50 IU ${\alpha}$-tocopherol/kg (T1), 100 IU ${\alpha}$-tocopherol/kg (T2), 200IU ${\alpha}$-tocopherol/kg (T3), 0.3 ppm selenium/kg (T4), and 100 IU ${\alpha}$-tocopherol/kg + 0.3 ppm selenium/kg (T5) for five weeks. Growth performance and proximate composition of chicken thigh meat were not influenced by all dietary treatments, except for crude fat, which was significantly lower in the treatment with ${\alpha}$-tocopherol or selenium, or both compared to control. The dietary ${\alpha}$-tocopherol and selenium supplementation had no significant effects on pH, CIE $L^*$ (lightness), and $b^*$ (yellowness) values but TBARS (thiobarbituric acid reactive substance) values were decreased (P<0.05) by the addition of ${\alpha}$-tocopherol and selenium. CIE $a^*$ (redness) values increased significantly with added ${\alpha}$-tocopherol and selenium relative to the control (P<0.05). Likewise, changes in fatty acid composition in chicken thigh meat with the dietary supplementations with ${\alpha}$-tocopherol, selenium and their combination significantly increased (P<0.05) unsaturated fatty acid, whereas saturated fatty acid were decreased. It was concluded that the addition of 200 IU ${\alpha}$-tocopherol (T3) and 100 IU of ${\alpha}$-tocopherol plus 0.3 ppm selenium (T5) were most effectiveness in the improvements in the lipid oxidative stability of chicken meat when compared to the control.

• Food Science of Animal Resources
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• v.28 no.2
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• pp.171-180
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• 2008

This study was conducted to investigate the meat quality characteristics of pork loin in 3 crossbred groups (30 pigs/group). The crossbreeds were LY female${\times}$D male, Y female${\times}$B male and L female${\times}$B male (L: Landrace, Y: Yorkshire, B: Berkshire, D: Duroc). Pork loins were collected from animals ($110{\times}120kg$ body weight) slaughtered in a commercial slaughter house and stored at $-3^{\circ}C$. Samples were analyzed for general composition, physico-chemical properties, meat and fat color, texture characteristics, sensory evaluation and fatty acid composition at 24 hrs postmortem, and TBARS (Thiobarbituric Acid Reactive Substances) values were determined at various storage times. The LYD pigs showed a higher back fat thickness than the YB and LB pigs. There were no significant differences in intramuscular fat, intermuscular fat, subcutaneous fat and springiness among the 3 crossbreeds. In addition, there were no significant differences in general composition, pH, drip loss, cooking loss and cooked sensory evaluation among the 3 crossbreeds (p>0.05). The shear force value of LB pork was significantly lower than other crossbreeds (p<0.05). Total heme pigment was significantly higher in YB pork compared to LYD and LB pork (p<0.05). The TBARS value of YB pork was significantly lower than that of LYD pork, except after the I day of storage (p>0.05). TBARS values increased significantly during storage for all three crossbreeds. The lightness (CIE L) of YB pork was significantly lower, while the redness (CIE a) was significantly higher in YB pork relative to the other crossbreeds. With regard to textural properties, the hardness and adhesiveness values were significantly lower in YB pork compared to LB pork. In fresh meat, the color of YB pork was significantly higher than the other breeds (p<0.05). The content of myristic acid (C14:0) was significantly lower, while the content of arachidonic acid (C20:4) was significantly higher in LB pork (p<0.05). These results show that the YB breed has the highest quality meat of the three crossbreeds.

• Food Science of Animal Resources
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• v.28 no.1
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• pp.51-58
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• 2008

This study was performed to evaluate the physico-chemical properties of fermented sausages containing probiotic starter cultures (LK-30 plus, Lactobacillus plantarum 155 and 167, and Pediococcus damnosus L12) with reduced fat levels, and to determine the optimum condition for the manufacture of these products. Although low-fat fermented sausages were reduced fat content at the amount of 90% and the ripening time by 1-2 weeks, as compared to regular-fat counterpart, they became harder and had many winkles outside due to the extreme drying. In addition, fat level in fermented sausages affected the composition and shear force values. During ripening, pH, lightness and yellowness values tended to decrease, however, microbial counts of inoculated lactic acid bacteria were increased up to $10^8-10^9cfu/g$ within 3 days and remained constant thereafter. Low-fat fermented sausages had higher microbial counts than regular-fat ones. Although the inoculated probiotic starter cultures alone had the functional properties, such as cholesterol reduction, anti-high blood pressure and antimicrobial activity, they did not have distinctive characteristics in the fermented sausages. Based on these results, the low-fat fermented sausages were successfully manufactured, but a little bit increased fat level and improved functional properties in the fermented sausages would be required to have better quality as compared to regular-fat counterparts.

• Journal of Animal Science and Technology
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• v.47 no.5
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• pp.721-730
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• 2005

Effects of levels of Bomboo Vinegar Liquids(BVL) on growth performance, serum profile and meat quality in employing 90 pigs were investigated. Ninety pigs were allocated into 3 groups and fed by dietary levels of BVL 0(control), 2.0 and 4.0% were included in experimental diets of each of the groups. Concentrated diet was supplemented with 2.0 and 4.0% BVL. The results showed that the daily weight gains and the feed conversion increased significantly(p<0.05) in 2.0% BVL and the feed intake increased slightly. The glucose and the cholesterol contents at the serum decreased significantly(p<0.05) in 2.0 and 4.0% BVL. On the other hand the total protein concentration and the blood urea nitrogen(BUN) increased significantly(p<0.05) in 4.0% BVL. The carcass weight increased significantly(p<0.05) in 4.0% BVL, and back fat thickness had decreased significantly(p<0.05) in 2.0 and 4.0% BVL. The carcass grade tended to increase in 2.0 and 4.0% BVL. The total fat content of loin tended to increase in 2.0 and 4.0% BVL while the cholesterol content decreased significantly(p<0.05). The pH had lower slightly in 2.0 and 4.0% BVL, the lightness and the yellowness of the meat color had higher significantly(p<0.05) while the redness decreased. Shear force values had lower significantly(p<0.05) in 2.0 and 4.0% BVL. For the fatty acid composition, the saturated fatty acids decreased significantly(p<0.05) in 2.0 and 4.0% BVL while unsaturated fatty acids(oleic acid and linoleic acid) increased significantly(p<0.05). For the sensory evaluation, 2.0 and 4.0% BVL had a significant(p<0.05) effect of diminishing the odor and improving the appearance. The taste was also significantly(p<0.05) improved. In conclusion the 2.0% BVL had a positive effect on the feeding performance, the carcass grade and the meat quality characteristics therefore 2.0% BVL is the appropriate supplemental levels of BVL for finishing pigs.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.50-55
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• 2010

This study was conducted to investigate the shelf-life and quality of breads made with 0.5, 1 and 2% of Myagropsis myagroides fermented ethanol extracts (MOE). The total microbial count in breads made with 2% MOE decreased to about 1.6 log cycles as compared to that of breads not containing MOE. The protection index measured by rancimat increased with an increase in the quantity of MOE in the breads. During the storage period, the pH value was not different between breads containing MOE and breads not containing MOE. The lightness and redness of the breads decreased with an increase in the quantity of MOE, while the yellowness increased. In the sensory evaluation, the breads containing 0.5% MOE were more preferred than the breads not containing MOE. These results suggest that the addition of 0.5% MOE to breads has a good effect on improving the shelf-life and overall quality.

• Journal of Animal Science and Technology
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• v.48 no.5
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• pp.727-738
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• 2006

This study was carried out to investigate the effect of feeding levels and periods of Rhus verniciflua Stokes (RVS) on the quality of M. longissimus from gilts (Landrace×Yorkshire×Duroc) at finishing stage. The gilts were fed diets containing 0 (control), 2 and 4% RVS for 5 weeks (the latter feeding periods) and 8 weeks (the first feeding periods+the latter feeding periods) before slaughtering, respectively. Samples were stored at 3±0.2℃ for 8 days. Crude fat content was decreased by feeding diets of 4% RVS (p<0.05). Water-holding capacity (WHC) was higher in RVS treatments than in control during storage (p<0.05). L*(Lightness) value was higher in 5 weeks-RVS treatment than in control during storage (p<0.05). a*(Redness) and b*(yellowness) were not affected by the levels and periods of RVS supplementation. Thiobarbituric acid reactive substances (TBARS) value was lower in RVS treatment than in control (p<0.05), and the 5 weeks with 4% RVS treatment showed the highest antioxidative activity. Fatty acid compositions of pork were changed by RVS feeding levels and periods. The meat supplemented with RVS showed high levels of unsaturated fatty acid (UFA) composition and monounsaturated fatty acid (MUFA)/saturated fatty acid (SFA) ratio compared with control. The dietary 8 weeks-RVS treatments had lower stearic acid(18:0) and higher polyunsaturated fatty acid (PUFA) contents than in other treatments. Melting point of backfat also decreased by increasing the level and period of RVS supplementation (p<0.05). Therefore, RVS fed pork decreased fat content and melting point, increased WHC and UFA composition, and delayed lipid oxidation during storage.