• Food Science of Animal Resources
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• v.24 no.1
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• pp.15-22
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• 2004

The effects of carcass grade and addition of mugwort powder on the quality of the boiled pork were investigated. Four kinds of boiled pork were denoted as B$\_$+/ or E$\_$+/ boiled porks which were made with 0.3% mugwort powder to carcass grade B or E, respectively, and B$\_$0/ or E$\_$0/ boiled porks which were made without mugwort powder. The effect of carcass grade and the added mugwort powder on the pH, volatile basic nitrogen(VBN), bacterial count, calorie, essential amino acids, free amino acids, unsaturated fatty acids, color difference and palatability of boiled porks were not significant. Water holding capacity(WHC), springiness and Hunter's L$\^$＊/ value of B$\_$0/ boiled pork were higher than those of E$\_$0/ boiled pork. Hunter's a$\^$＊/ value of B$\_$0/ boiled pork were lower than those of E$\_$0/ boiled pork. Sensory taste and tenderness value of B$\_$0/ boiled pork were higher than those of E$\_$0/ boiled pork(p>0.05). WHC, 2-thiobarbituric acid reactive substances(TBARS) value and residual nitrite of boiled pork with mugwort powder were lower than those of boiled pork without mugwort powder.

• Journal of Food Hygiene and Safety
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• v.35 no.2
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• pp.170-176
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• 2020

We investigated the pH, volatile basic nitrogen (VBN), microbial changes and dominant microbes in raw beef, wet-aging beef, and dry-aging beef after the meat had been stored in a refrigerator. The count of mesophilic bacteria was 3.3-3.9 log CFU/g in raw beef and dry-aging beef, and 5.4 log CFU/g in wet-aging meat. After 18 days of refrigeration, the mesophilic bacterial count in raw and aging beef increased to 6.1-6.4 log CFU/g. In wet-aging beef, the number of lactic acid bacteria increased from 4.5 log CFU/g to 6.0 log CFU/g at refrigeration temperature. However, lactic acid bacteria were not detected in dry aging beef. Major foodborne pathogens such as Salmonella spp, Listeria monocytogenes, and Escherichia coli (EHEC) were not detected. Based on the legal standard for mesophilic bacteria count, the estimated shelf-life of aged beef was less than 12 days and the average VBN was 15 mg%. The dominant microorganisms varied between the different types of meat. In raw meat, Staphylococcus saprophyticus was the dominant microorganism, and as the VBN increased, Carnobacterium divergens dominated. In wet-aging beef, Carnobacterium divergens dominated during the initial days of refrigeration after which the number of Lactobacillus sakei increased. Dermacoccus nishinomiyaensis was initially the dominant microbe in dry-aging beef, after which Pseudomonas fragi dominated. In addition to the role of specific bacteria in the early stage of decay, it is thought that microorganisms can be utilized for safe distribution and storage of matured meats by conducting research on changes in rot, fragrance analysis, and changes of ingredients in matured meats.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.10
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• pp.1643-1653
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• 2018

Objective: This study investigated the effect of dietary crude protein (CP) supplementation on nutrient intake, nitrogen (N) utilisation, blood metabolites, ruminal fermentation and growth performance of young Holstein bulls. Methods: Twenty-one young bulls weighing $277{\pm}11.2kg$ were equally divided into three groups and were offered diets formulated with low CP (LCP; 10.21% CP and 4.22% rumen degradable protein [RDP]), medium CP (MCP; 12.35% CP and 5.17% RDP) and high CP (HCP; 14.24% CP and 6.03% RDP). Yellow corn silage was used as a unique forage source and was mixed with concentrate. This mixed feed was given ad libitum to the young bulls included in the study. Results: Results showed that CP intake, blood urea nitrogen, N intake, total N excretion and N balance increased linearly with an increase in dietary CP level (p<0.05). However, no significant difference was observed in nutrient digestibility among the bulls receiving the different diets. Ruminal pH (p<0.05) and ammonia nitrogen ($NH_3-N$) concentration (p<0.01) were significantly higher in the bulls receiving the MCP and HCP diets than in those receiving the LCP diet. The bulls receiving the HCP diet showed significantly higher ruminal bacterial protein level, propionate, acetate and total volatile fatty acid (TVFA) concentrations than bulls receiving the LCP diet (p<0.05). Moreover, dietary CP level exerted a significant positive effect on the final body weight, average daily gain and gain-to-feed ratio of the bulls (p<0.05). Conclusion: High dietary CP level is optimal for achieving maximum growth and high profitability without exerting a negative effect on the physiology of growing Holstein bulls.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.10
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• pp.1424-1436
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• 2013

The objective of this study was to investigate the effect of banana flower powder (BAFLOP) supplementation on gas production kinetics and rumen fermentation efficiency in in vitro incubation with different ratios of roughage to concentrate in swamp buffalo and cattle rumen fluid. Two male, rumen fistulated dairy steers and swamp buffaloes were used as rumen fluid donors. The treatments were arranged according to a $2{\times}2{\times}3$ factorial arrangement in a Completely randomized design by using two ratios of roughage to concentrate (R:C; 75:25 and 25:75) and 3 levels of BAFLOP supplementation (0, 2 and 4% of dietary substrate) into two different kinds of rumen fluid (beef cattle and swamp buffalo). Under this investigation, the results revealed that the rumen ecology was affected by R:C ratio. The pH declined as a result of using high concentrate ratio; however, supplementation of BAFLOP could buffer the pH which led to an improvement of ruminal efficiency. BAFLOP supplementation affected acetic acid (C2) when the proportion of concentrate was increased. However, there were no effect on total volatile fatty acid (TVFA) and butyric acid (C4) by BAFLOP supplementation. The microbial community was affected by BAFLOP supplementation, especially the bacterial population. As revealed by real-time PCR, the populations of F. succinogenes and R. albus were reduced by the high concentrate treatments while that of R. flavafaciens were increased. The populations of three dominant cellulolytic bacteria were enhanced by BAFLOP supplementation, especially on high concentrate diet. BAFLOP supplementation did not influence the ammonia nitrogen ($NH_3$-N) concentration, while R:C did. In addition, the in vitro digestibility was improved by either R:C or BAFLOP supplementation. The BAFLOP supplementation showed an effect on gas production kinetics, except for the gas production rate constant for the insoluble fraction (c), while treatments with high concentrate ratio resulted in the highest values. In addition, BAFLOP tended to increase gas production. Based on this study, it could be concluded that R:C had an effect on rumen ecology both in buffalo and cattle rumen fluid and hence, BAFLOP could be used as a rumen buffering agent for enhancing rumen ecology fed on high concentrate diet. It is recommended that level of BAFLOP supplementation should be at 2 to 4% of total dry matter of substrate. However, in vivo trials should be subsequently conducted to investigate the effect of BAFLOP in high concentrate diets on rumen ecology as well as ruminant production.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.4
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• pp.585-594
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• 2018

Objective: This study was to determine the bacterial diversity and monitor the community dynamic changes during storage of vacuum-packaged sliced raw beef as affected by Lactobacillus sakei and Lactobacillus curvatus. Methods: L. sakei and L. curvatus were separately incubated in vacuumed-packaged raw beef as bio-protective cultures to inhibit the naturally contaminating microbial load. Dynamic changes of the microbial diversity of inoculated or non-inoculated (control) samples were monitored at $4^{\circ}C$ for 0 to 38 days, using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Results: The DGGE profiles of DNA directly extracted from non-inoculated control samples highlighted the order of appearance of spoilage bacteria during storage, showing that Enterbacteriaceae and Pseudomonas fragi emerged early, then Brochothrix thermosphacta shared the dominant position, and finally, Pseudomonas putida showed up became predominant. Compared with control, the inoculation of either L. sakei or L. curvatus significantly lowered the complexity of microbial diversity and inhibited the growth of spoilage bacteria (p<0.05). Interestingly, we also found that the dominant position of L. curvatus was replaced by indigenous L. sakei after 13 d for L. curvatus-inoculated samples. Plate counts on selective agars further showed that inoculation with L. sakei or L. curvatus obviously reduced the viable counts of Enterbacteraceae, Pseudomonas spp. and B. thermosphacta during later storage (p<0.05), with L. sakei exerting greater inhibitory effect. Inoculation with both bio-protective cultures also significantly decreased the total volatile basic nitrogen values of stored samples (p<0.05). Conclusion: Taken together, the results proved the benefits of inoculation with lactic acid bacteria especially L. sakei as a potential way to inhibit growth of spoilage-related bacteria and improve the shelf life of vacuum-packaged raw beef.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.1
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• pp.157-165
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• 2020

Objective: The objective of this study was to compare the quality of dry-aged beef from cull Hanwoo cows slaughtered at 60 or 80 months old. Methods: A total of eight cull Hanwoo carcasses with a quality grade of 3 (low-grade) were selected and divided into two age groups: 63.5±2.5 months old (n = 4) and 87.8±4.5 months old (n = 4). Whole longissimus thoracis et lumborum from the 11th rib to the last lumbar vertebrae, including the back fat, was removed from the carcass at 24 h postmortem and aged for 50 days in darkness at a temperature of 2℃±1℃, a relative humidity of 85% and an air flow of 2 m/s. The sampling was performed aseptically after 0, 20, 24, 40, and 50 days of aging. Results: Regardless of the aging period, aging increased the lightness (p<0.05), redness (p<0.05) and yellowness (p<0.05) at initial blooming (90 min after slicing) and the overall acceptance (p<0.05). No further tenderization effect was found after 20 days of aging, but aging for 50 days significantly increased the lipid oxidation (p<0.05). The generation of aroma volatiles in the roast steak from aged samples was higher (p<0.05) than that of non-aged samples. No significant effect of age at slaughter was found on the color, pH, water-holding capacity, cooking loss, shear force value, bacterial counts, volatile basic nitrogen, consumer acceptance, lipid oxidation, fatty acid composition or aroma volatiles. Conclusion: The quality of dry-aged beef obtained from cull Hanwoo cows slaughtered at either 60 or 80 months old with similar quality grade was comparable and extending dry aging for more than 40 days is not recommended considering the costs and further lipid oxidation.

• Journal of Animal Environmental Science
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• v.1 no.1
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• pp.55-64
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• 1995

A wastewater purifying system using phototrophic bacterium, Rhodopseudomonas capsulata, is currently in operation in several countries, One of them, is a continuously aerated bioreactor(CABR) system, which treats concentrated swin wasterwater using small amounts of phototrophic bacteria as additive bacterial seeding. Using this plant, total biochemical oxygen demand was decreased to 13%, and most of volatile fatty acids were removed. About 40% of the wastewater(Influx) was evaporated during aerobic digestion for 24h, and 60% of that erupted in a decodorized foam(Efflux). The efflux had enough nutrients, N, P and K kor growing plant, as well as organic matters. When the efflux was applied to Italian ryegrass with high dose, fresh shoot and root weights were significantly greater, and $NO_3-N$ contents of the dried shoot were lower than those of control plant (CDU). These results indicate that the CABR plant is useful for reduction and deodorization of swine wastewater and the efflux from CABR can be used for crop production as an organic fertilizer.

• Journal of Food Hygiene and Safety
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• v.25 no.1
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• pp.59-64
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• 2010

The effects of vinegar, alcohol and ascorbic acid on the color, microorganism, sensory properties and flavor pattern of minced ginger (MG) were investigated during storage for 28 days at $30^{\circ}C$. The values of L (lightness), a (redness) and b (yellowness) of the control (T-0) and all the treatments changed slightly at the initial stage of storage, however the elapse of time accelerated the changes. The total bacterial counts of T-0 showed $5.37{\times}10^7\;CFU/g$ at the initial stage, but the MG-treatments decreased the bacteria above 4 log compared to T-0. It was showed that the additives were effective for inhibition of the growth of microorganism. Sensory properties of flavor intensity test showed no significant difference between T-0 and MG-treatments (p < 0.05). The result of volatile flavor contents of electronic nose analyzer (ENZ) showed that MG-treatments (T-I, T-II, T-III) was recognized stronger than non-treatment at the initial stage, but the change of flavor compound were stabilized soon regardless of type or quantity of additives during total storage period at $30^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.46 no.6
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• pp.689-693
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• 2014

Flounder sikhe is one of the traditional Korean fermented foods. Because honey, fucoidan, propolis, aronia berry, and horseradish are well known to have natural antimicrobial properties, we investigated their antimicrobial effects on improving the quality of flounder sikhe. Ethanol extracts of propolis inhibited the growth of Bacillus cereus, Staphylococcus aureus, and Listeria monocytogenes. The extracts of aronia berry showed similar effects against Salmonella Typhimurium. We also assessed the total polyphenol and total flavonoid content and 2,2-diphenyl-2-picrythydrazyl (DPPH) radical scavenging activity in the extracts obtained from these natural materials. The contents of polyphenols and flavonoids were the highest in propolis, which also showed a high DPPH radical scavenging activity. Therefore, addition of propolis 0.5% to flounder sikhe showed optimal improvement, with a storage stability of 15 days at pH 5.39, volatile basic nitrogen (VBN) content at 24.73 mg/100 g, and total bacterial count at $1.81{\times}10$ colony forming unit (CFU)/g.

• Journal of Life Science
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• v.14 no.2
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• pp.239-244
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• 2004

This study was carried out to clarify the effect of addition of mugwort and carcass grade on the quality and sensory properties of loin hams. The volatile basic nitrogen, 2-thiobarbituric acid reactive substances, total bacterial count, water holding capacity and calorie of loin hams were not significantly different among hams, but the pH and residual nitrite of loin hams with mugwort were significantly lower than that of loin hams without mugwort. The fat content of grade B loin hams were higher than that of grade E loin hams, and the protein and total amino acid content of grade E loin hams were higher than that of grade B loin hams. The free amino acid, saturated fatty acid and unsaturated fatty acid were not significantly different among loin hams. The $L^{＊}$ value of grade B loin hams were higher than that of grade E loin hams, the a value of grade E loin hams were higher than that of grade B loin hams, and the $b^{＊}$ value was not significantly different among loin hams. The hardness, springiness, cohesiveness, gumminess and chewiness were not significantly different among loin hams. The aroma of loin hams without mugwort were superior than that of loin hams with mugwort, and the juiciness of grade B loin hams were superior than that of grade E loin hams. But the color, taste, texture and palatability were not significantly different among loin hams.