• Applied Biological Chemistry
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• v.30 no.3
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• pp.210-218
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• 1987

In the previous report, we isolated and purified one of tendering enzyme 'ficin' from fig latex. In this study, various crude ficin concentrations and reaction time were employed to investigate the contents of free amino acids and other free nitrogen compounds after the treated with beef round muscle. 1. Free amino acids contents increased with the increase of temperature and time during the aging of beef at $1^{\circ}C$ and $8^{\circ}C$, and the increasing rate was remarkably high when fresh beef was treated with ficin. In the case of ficin treatment after various cooking, steaming showed the highest increase in free amino acid contents among three cooking methods such as boiling, steaming and pan broiling. The increased amounts of free amino acids in three groups-aging beef at $1^{\circ}C$ for 3 days, fresh beef treated with ficin(0.1%, 2hrs) and beef treated with ficin(0.1%, 2hrs) after cooking were 13%, 293% and 137% respectively. In contrast to aging group, the amount of free amino acids in other two groups treated with ficin was superiorly increased. 2. The amounts of total free nitrogen, free non-protein nitrogen and $NH_3-nitrogen$ increased with the increase of temperature and time during the aging of beef at $1^{\circ}C$ and $8^{\circ}C$, and the increasing rate was remarkably high in fresh beef treated with ficin. In the case of ficin treatment after cooking, steaming gave larger amount of total and non-protein nitrogen than other two cooking, e.g. boiling and panbroiling. The increasing rate of nonprotein nitrogen to the total nitrogen of fresh beef treated with ficin(0.1%, 2hrs) was 75 times greater than that of aging fresh beef at $1^{\circ}C$ for 3 days.

• Food Science of Animal Resources
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• v.32 no.6
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• pp.796-802
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• 2012

This study was conducted in order to investigate the effect of different drying methods on free amino acids and dipeptide contents, Warner-Bratzler shear force and sensory property of beef jerky products. The drying methods used for this study were sun-drying, shade-drying and hot air-drying methods. The sun-dried beef jerky had the highest free amino acids (277.45 mg/100 g) followed by shade-dried (206.43 mg/100 g) and hot air-dried (111.88 mg/100 g) ones, whereas the amount of dipeptides were the highest in the shade-dried beef jerky followed by sun-dried and hot air-dried ones. The fatty acid composition of the beef jerky was not shown any difference among the beef jerkies with 3 different drying methods. The color $L^*$-value of the beef jerky was lower in the hot-air dried, while the $a^*$-value was higher in the sun-dried one. The shade-dried jerky showed a lower $b^*$-value. The shear force of beef jerky was lower when it was either sun-dried or shade-dried than when it was hot air-dried. Sensory evaluation revealed that hot air-dried beef jerky scored lower than the sun-dried and shade-dried ones (p<0.05). Therefore, using either the sun drying or shade drying methods is more desirable than using the hot air drying method when manufacturing beef jerky for superior physicochemical qualities.

• Korean Journal of Agricultural Science
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• v.45 no.2
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• pp.211-218
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• 2018

Different packaging methods and storage temperatures were tested to determine the storage stability of beef dry-aged for 21 days based on microbial, physicochemical, and sensory qualities. After completion of the dry aging, the dried surface of beef sirloin was trimmed off, and the beef was packaged using two different methods (oxygen-permeable wrap or vacuum packaging) and stored at different temperatures ($3{\pm}2^{\circ}C$ or $-23{\pm}2^{\circ}C$) for 0, 7, 14, or 21 days. Lipid oxidation and the sensory quality of the dry-aged beef were not affected by the packaging method and storage temperature during storage. No microbial growth was observed over the storage period in the vacuum-packaged dry-aged beef, regardless of the storage temperature. However, dry-aged beef in the oxygen-permeable wrap packaging showed microbial spoilage with 8.82 log CFU / g at day 7 of the refrigerated storage. The vacuum-packaged dry-aged beef showed the lowest values (p < 0.05) in $a^*$ and chroma at days 14 and 21 at $3^{\circ}C$, and days 7 and 14 at $-23^{\circ}C$, respectively. Therefore, it is recommended that dry-aged beef with wrap packaging stored in refrigerated conditions should be consumed as quickly as possible due to microbial growth. For long-term storage, dry-aged beef should be frozen because freezing can extend the color stability up to day 21 of storage without adverse effects on the hygienic or meat quality aspects of dry-aged beef.

• Food Science and Biotechnology
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• v.16 no.4
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• pp.576-579
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• 2007

The effects of temperature and Korean bramble (Rubus coreanum Miquel) tissue concentrate on heterocyclic aromatic amine (HAA) formation in fried ground beef patties were investigated. Various amounts of Korean bramble tissue (4.0, 7.0, and 11.0%, w/w) were added to ground beef patties were fried at 2 different temperatures (190 and $225^{\circ}C$) for 10 min/side. It was observed in the fried ground beef patties fried at $190^{\circ}C$ with the addition of 11.0%(w/w) Korean bramble that the mutagenicity decreased by 64%, and formation of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and 2-amino-I-methyl-6-phenylimidazo[4,5-b]-pyridine(PhIP) reduced by 55 and 86%, respectively. Although no difference in total mutagenicity was shown in patties fried at $225^{\circ}C$ with the addition of 4.0, 7.0, and 11.0%(w/w), different levels of reduction of PhIP formation in patties fried at $225^{\circ}C$ with the addition of 4.0, 7.0, and 11.0%(w/w) were shown 49, 63, and 75%, respectively.

• Korean journal of food and cookery science
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• v.12 no.2
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• pp.123-128
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• 1996

Tenderness of loin and brisket muscles of Korean and imported beef was measured using the Time-lntensity (Tl) techniques. From the Tl curve, the Rx, Imax, Dur and AUC parameters were determined. For the loin muscle, Korean beef showed significantly (p < 0.05) larger Rx, Imax, and AUC. This result represents Korean beef loin has higher tenderness than that of imported one. For the brisket muscle, imported beef show.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.05a
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• pp.145-149
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• 2005

This study was carried out to investigate the effect of dietary RVS on the WHC, color stability, and lipid oxidation of Hanwoo (Korean cattle) beef during cold storage after thawing, RVS fed Hanwoo (Korean cattle) beef was more effective in increasing WHC, color stability and delaying lipid oxidation than that without RVS in diet. And 4% RVS fed Hanwoo (Korean cattle) beef showed the greatest effects.

• Korean Journal of Veterinary Service
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• v.35 no.4
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• pp.313-319
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• 2012

Consumer's preference and microbial inspections on fresh raw beef were carried out to understand the actual market status in Gwanju, Korea. Over 15 questions on questionnaire by 1,111 randomly selected respondents between April and May in 2011, results showed 65.5% positive on eating fresh raw beef, 63.8% negative on good hygiene condition of fresh raw beef, and 72.5% positive on the secure of the hygiene-safety for priority program, respectively. For microbial inspections, a total of 302 samples were collected from fresh raw beef purchased from slaughterhouse (n=122), transport (n=69) and consumer (n=81) stage, from lettuce (n=30) at consumer stage. The aerobic plate count (APC), E. coli count and food borne bacteria such as Salmonella spp., Listeria monocytogenes, Staphylococcus(S.) aureus and E. coli O157:H7 were tested in the samples. As results, the level of count on APC of fresh raw beef ranged $6{\times}10^1{\sim}1.8{\times}10^5CFU/g$ from slaughterhouse, $2{\times}10^2{\sim}8.3{\times}10^5CFU/g$ from transport stage and $1{\times}10^2{\sim}4{\times}10^5CFU/g$ from consumer stage. The level of count on E. coli of fresh raw beef ranged $1{\sim}9{\times}10^1CFU/g$ from slaughterhouse, $1{\sim}7{\times}10CFU/g$ from transport stage and $1{\sim}5.5{\times}10CFU/g$ from consumer stage. In total, 26 S. aureus were isolated, 10 (14.5%) from fresh raw beef at transport stage, 12 (14.8%) from fresh raw beef and 4 (13.3%) from lettuce at consumer stage. Enterotoxin of S. aureus was not detected among 26 isolates. All S. aureus isolates were typed using a DiversiLab$^{TM}$ rep-PCR system for genetic similarity test, showing over 95% of genetic relationship amon isolates.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.388-393
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• 1998

Recently there has been an increasing amount of foreign livestock products distributed in the domestic market due to the market opening. Some vicious dealers sell the foreign beef in the trade name of the native beef during the final distribution step to arouse the social criticism frequently. In this report, we investigated a method to distinguish the native beef from the foreign one scientifically using the PCR-RAPD, a recent gene technique. Hygienical safety was also examined using a microbiological test for toxicity of Escherichia coli 0157:H7 and the food poisoning bacteria. The conditions of DNA amplification for the PCR analysis were $1{\times}Taq$ polymerase buffer, 1.5 mM $MgCl_2,\;50\;\mu\textrm{M}$ dNTP, 100 ng primers, 2.5 unit Taq polymerase and 5~20 ng template DNA, with the fmal volume of $50\;\mu\textrm{\ell}$. The size of the amplified product was detected mostly in the range of 0.5~2.0 kbp. The size of DNA, gene marking factor, which could be a criterion distinguishing the native beef from the foreign one, appeared approximately 1.2 kbp. The native beef was distinguished from the foreign beef with more than 90% of confidence by the gene marking factor. This method was expected to be useful in the breed discrimination between the native beef and the foreign one. The hygienical test results showed that, fortunately, neither Salmonella spp. and Listeria monocytogenes which form a principal cause of the food poisoning nor Enterohemorrhagic Escherichia coli : EHEC which have provoked a recent social disturbance, were detected at all.

• The Korean Journal of Food And Nutrition
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• v.15 no.3
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• pp.197-202
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• 2002

This study was carried out to investigate food additives, physico-chemical, sanitary state of the marketing jerky in domestic. The kind of sensory agents and food additives on the marketing jerky sample used 16~23 kinds, and the domestic processed by import beef was large number, but that domestic pork jerky was small number The moisture content on the import beef jerky were high, and crude protein on the import beef jerky and domestic pork jerky were high level, and crude fat on the domestic pork jerky were high, but crude ash on all jerky sample were similar level. Degree of saline on the import beef jerky was high, but the domestic beef jerky was low. The range of pH was 5.41~6.11, and that import beef jerky was little high, but the domestic beef jerky was low. Water activity value in pork jerky was 0.743, also had high, and domestic beef jerky was lowest than others jerky sample. Range of VBN value in jerky sample was 9.98~12.36mg%, and the range TBA value was 0.239~0.367, and that value showed difference in all jerky sample. The total general bacteria count of marketing jerky was 10$^3$~ 10$^4$ CFU/g, and import beef jerky was less higher than domestic beef and pork jerky.

• The Korean Journal of Food And Nutrition
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• v.15 no.3
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• pp.167-202
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• 2002

This study was carried out to investigate food additives, physico-chemical, sanitary state of the marketing jerky in domestic. The kind of sensory agents and food additives on the marketing jerky sample used 16~23 kinds, and the domestic processed by import beef was large number, but that domestic pork jerky was small number The moisture content on the import beef jerky were high, and crude protein on the import beef jerky and domestic pork jerky were high level, and crude fat on the domestic pork jerky were high, but crude ash on all jerky sample were similar level. Degree of saline on the import beef jerky was high, but the domestic beef jerky was low. The range of pH was 5.41~6.11, and that import beef jerky was little high, but the domestic beef jerky was low. Water activity value in pork jerky was 0.743, also had high, and domestic beef jerky was lowest than others jerky sample. Range of VBN value in jerky sample was 9.98~12.36mg%, and the range TBA value was 0.239~0.367, and that value showed difference in all jerky sample. The total general bacteria count of marketing jerky was 10$^3$~ 10$^4$ CFU/g, and import beef jerky was less higher than domestic beef and pork jerky.