• Preventive Nutrition and Food Science
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• v.6 no.2
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• pp.91-95
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• 2001

Competitive indirect enzyme linked immunosorbent assay (Ci-ELISA) was used to obtain the preliminary data for the detection of irradiated beef. Ci-ELISA was individually formatted with polyclonal antibodies produced from 2 kinds of bovine proteins, myosin and bovine serum albumin (BSA). Beef round, loin and tender loin were vacuum-packaged and subdivided into 3 groups of 1) irradiation; 2) irradiation and chilled at 4$^{\circ}C$ for 7 day; 3) irradiation and frozen at 2$0^{\circ}C$ for 2 months to observe the changes under different storage and/or distribution conditions. Irradiation was performed at 3, 5 and 7 kGy. Protein solutions prepared from the sample were tested by formatted Ci-ELISA. Detected concentrations of myosin and BSA decreased with the increased irradiation dose in all samples with different reduction rates. Myosin was more susceptible to freezing than BSA. Samples irradiated at 5 kGy or above could be differentiated from non-irradiated ones by Ci-ELISA. These results indicate that immunological assay can be used as a detection method for irradiated beef.

• Food Science of Animal Resources
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• v.35 no.4
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• pp.441-448
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• 2015

Blanching beef for use in home meal replacements (HMR) is an important process that determines the final quality of the beef after the cooking process. Thermal pretreatment also minimizes the change in quality during the main cooking process or storage. In this study, beef samples were washed and sliced, then treated by immersion in boiling water (1-10 min), steaming (1-10 min), or pan-frying in oil (30-240 s). The color after each thermal treatment showed higher L* and b* values and lower a* values compared with the raw beef, except for the pan-frying thermal treatment. The total color difference (∆E) and pH value were significantly increased by panfrying (p<0.05). There was no significant difference in the shear force of the beef samples, except for the sample pan-fried for 210 s. The nutritional content of beef was measured as the moisture, protein, fat, and ash contents, which were 69.96, 16.64, 3.49, and 1.13%, respectively, in raw beef. After thermal treatment, the crude protein and fat contents were increased, whereas the moisture and ash contents decreased. The mineral content, including Na, Mg, Fe, and Ca was highest after pan-frying. The heat treatment decreased microorganisms in all the samples. The total bacteria count in raw beef was 4.5-4.7 Log CFU/g, whereas the bacteria count decreased to 2.2-2.8 Log CFU/g after blanching. Thermophilic bacteria, coliform, mold, and yeast not detected in any thermally treated sample.

• Journal of Food Hygiene and Safety
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• v.3 no.1
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• pp.19-26
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• 1988

Most of meat spoilage bacteria area Gram negative, which are very sensitive to freezing ; for instance , 90% of E. coli cells are killed or sub-lethally injured by freezing at -3$0^{\circ}C$, and the freeze-injury rate is dependent upon freezing rate. Since the injured bacterial cells are sensitive to selective agents, they fail to multiply in selective media. Injured bacterial cells are, however, capable of spontaneous repair at appropriate environmental and nutritional conditions . Enumeration of injured bacterial cells involves artificial induction of repair at these conditions. Cubic beef samples(3$\times$3$\times$3cm) were frozen at -6$0^{\circ}C$, -4$0^{\circ}C$, or -18$^{\circ}C$. The samples frozen at each temperature were thawed at 4$^{\circ}C$, 2$0^{\circ}C$, or by microwave . After these respective freezing an thawing treatments, the percentage of sub-lethally injured total coliforms out of total surviving ones was measured and compared. The results were as follows: 1. The interaction between freezing and thawing on injury rate was not significant. 2. The injury rates(as means of all three thawing treatments post-freezing) by freezing at -6$0^{\circ}C$, -4$0^{\circ}C$, or -18$^{\circ}C$ were 32.2$^{\circ}C$ and 19.2$^{\circ}C$ respectively . 3. The injury rates(as means of all three freezing treatments)by thawing at 4$^{\circ}C$, 2$0^{\circ}C$, or by microwave were 49.3%, 11.7% and 21.0% respectively. The highest injury rate was caused by freezing at -6$0^{\circ}C$ and subsequent thawing at 4$^{\circ}C$. However since the injury rates by freezing treatment were not significantly different, freezing at -18$^{\circ}C$ and subsequent thawing at 4$^{\circ}C$ can also be recommended , from an economic perspective.

• Food Science of Animal Resources
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• v.35 no.6
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• pp.772-782
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• 2015

This study was performed to explore the deterioration of physicochemical quality of beef hind limb during frozen storage at −20℃, affected by repeated freeze-thaw cycles. The effects of three successive freeze-thaw cycles on beef hind limb were investigated comparing with unfrozen beef muscle for 80 d by keeping at −20±1℃. The freeze-thaw cycles were subjected to three thawing methods and carried out to select the best one on the basis of deterioration of physicochemical properties of beef. As the number of repeated freeze-thaw cycles increased, drip loss decreased and water holding capacity (WHC) increased (p<0.05) till two cycles and then decreased. Cooking loss increased in cycle one and three but decreased in cycle two. Moreover, drip loss, WHC and cooking loss affected (p<0.05) by thawing methods within the cycles. However, pH value decreased (p<0.05), but peroxide value (p<0.05), free fatty acids value (p<0.05) and TBARS value increased (p<0.05) significantly as the number of repeated freeze-thaw cycles increased. Moreover, significant (p<0.05) interactive effects were found among the thawing methods and repeated cycles. As a result, freeze-thaw cycles affected the physicochemical quality of beef muscle, causing the degradation of its quality.

• Food Science of Animal Resources
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• v.20 no.4
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• pp.288-295
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• 2000

동결기간과 해동후 재냉장이 우육의 지방산 조성. TBA가 생육향 및 가열육향에 미치는 영향을 파악하기 위하여 홀스타인의 등심부위를 -2$0^{\circ}C$에서 6, 12 및 18개월 동경, 해동한 것과 이것을 1$^{\circ}C$에서 3일간 재냉장한 것에 대하여 실험하였다. 신선육의 총지질 중성지질 및 인지질의 단일 불포화지방산에 대한 포화지방산의 비율(MUFA/SFA)은 각각 1.35, 1.10 및 1.34이었으며 동결기간이 길어지면서 점점 감소하였다. 동결 6개월째 우육은 TBA가는 0.37 mg/MA/kg으로 신선육의 0.15 mg/MA.kg 보다 높아졌으나 산패취는 느끼지 못했다. 동결 12개월과 18개월째 우육의 TBA가는 각각 0.53과 0.64mg/MA/kg이었으며 산패취를 느낄수 있었다. 한편 재냉장한 우육은 동결기간에 관계없이 TBA가가 높아지고 생육향 평가 점수가 낮아졌으나 MUFA/SFA와 가열육향은 동결 6개월째에 향상되었고 12개월 및 18개월 째에는 저하되어 동결기간에 따라 재냉장 효과의 차이를 보였다.

• 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 of Animal Resources
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• v.37 no.3
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• pp.440-448
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• 2017

This study was conducted to establish the shelf life of $1^{++}$ grade Hanwoo beef by evaluating the changes in meat quality and storage stability under distribution conditions similar to those during export to Hong Kong and China. Four muscles of the loin, striploin, tenderloin, and top round muscles were obtained from 10 animals of $1^{++}$ grade Hanwoo steers. The distribution conditions were 0, 7, or 14 d of aging at $2^{\circ}C$ and continuous storage at $-18^{\circ}C$ for 0, 3, 6, or 9 mon. The lightness (CIE $L^*$) values decreased as the duration of freezer storage increased (p<0.05). The water-holding capacity of 4 muscles increased as the aging time increased when they were frozen for 3 mon (p<0.05). The cooking loss values of the four muscles were significantly increased as the duration of freezer storage increased (p<0.05). The Warner-Bratzler shear force values were significantly decreased in the loin, striploin, and top round muscles as the aging time increased (p<0.05). The changes in volatile basic nitrogen (16.67-18.49 mg%) and thiobarbituric reactive substance values (0.75-0.82 mg MA/kg meat) were significantly increased when the meat was frozen for 9 mon after 14 d of aging. On the basis of these observations, the shelf life of $1^{++}$ grade Hanwoo beef during distribution should be limited to less than 9 mon of freezer storage at $-18^{\circ}C$ after 14 d of aging at $2^{\circ}C$.

• Food Science of Animal Resources
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• v.31 no.1
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• pp.19-26
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• 2011

In this study, we evaluated the physicochemical and sensorial properties of frozen Hanwoo beef patties prepared from prerigor and post-rigor muscle with soybean sauce or sodium chloride. The pH of the soybean sauce treatments was lower than the sodium chloride treatments (p<0.05); however, the Hanwoo patty prepared from pre-rigor muscle with soybean sauce had a lower cooking loss and smaller diameter than the Hanwoo patty prepared under the same conditions from post-rigor muscle (p<0.05). The addition of the soybean sauce inhibited lipid oxidation due to the antioxidative materials in soybean sauce such as melanoidin. The hardness of patties prepared from pre-rigor treatment was lower relative to those prepared from post-rigor muscle (p<0.05); however, there was no significant difference between springiness, cohesiveness, and chewiness (p>0.05). In the sensory evaluation, patties prepared from pre-rigor muscle with soybean sauce had a significantly high score in all traits (p<0.05); thus, pre-rigor muscle with soybean had the highest overall acceptability. Furthermore, the addition of soybean sauce to pre-rigor muscle produced similar effects as those observed for the addition of sodium chloride in regards to psychochemical properties. Moreover, meat products produced from pre-rigor muscle will have better antioxidative and sensorial properties.

• Food Science of Animal Resources
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• v.34 no.6
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• pp.742-748
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• 2014

This study was conducted to evaluate the activities of antioxidant enzyme (glutathione peroxidase (GSH-Px)) and lysosomal enzymes (alpha-glucopyranosidase (AGP) and beta-N-acetyl-glucosaminidase (BNAG)) of the longissimus dorsi (LD) muscle from Hanwoo (Korean cattle) in three freezing conditions. Following freezing at -20, -60, and $-196^{\circ}C$ (liquid nitrogen), LD samples (48 h post-slaughter) were treated as follows: 1) freezing for 14 d, 2) 1 to 4 freeze-thaw cycles (2 d of freezing in each cycle), and 3) refrigeration ($4^{\circ}C$) for 7 d after 7 d of freezing. The control was the fresh (non-frozen) LD. Freezing treatment at all temperatures significantly (p<0.05) increased the activities of GSH-Px, AGP, and BNAG. The $-196^{\circ}C$ freezing had similar effects to the $-20^{\circ}C$ and $-60^{\circ}C$ freezing. Higher (p<0.05) enzymes activities were sustained in frozen LD even after 4 freeze-thaw cycles and even for 7 d of refrigeration after freezing. These findings suggest that freezing has remarkable effects on the activities of antioxidant enzyme and lysosomal enzymes of Hanwoo beef in any condition.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.2
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• pp.290-297
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• 2012

The nutritional composition of thawed Hanwoo beef fed no mugwort (T0) and thawed Hanwoo beef fed mugwort (T1) were analyzed after freezing at $-20^{\circ}C$ for 12 months. Also the effect of feeding mugwort was investigated by comparing physicochemical and palatability changes by chilling the beef after thawing. There were no significant differences in general components of T0 and T1 Hanwoo beef. Among the minerals, there were no significant differences in the contents of Ca, P, K, Mg and Zn, however Na content in T0 and Fe content in T1 were significantly higher. The total amino acid did not show a significant difference but leucine was found to be higher in T0 than T1, and glycine, cysteine, histidine and arginine were higher in T1 than T0. Regarding fatty acids, stearic acid was higher in T0, while palmitoleic acid, oleic acid and total unsaturated fatty acid was significantly higher in T1. The hardness value became lower by chilling after thawing regardless mugwort consumption, and therefore the tenderness improved. The freshness, fat rancidity and antioxidant activity of thawed Hanwoo beef changed more slowly for T1 than T0, which indicates that feeding mugwort had a positive effect. There were no significant differences in taste, juiciness, tenderness or and palatability of the cooked beef between T0 and T1 for both 0 days and 3 days after thawing. However, the aroma of cooked T1 beef was significantly superior.