• Food Science of Animal Resources
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• v.38 no.5
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• pp.1101-1108
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• 2018

The aim of this study was to investigate the effects of dry-aging (DA) and the cooking process on the myofibril protein functionalities and in vitro digestibility of proteins in beef loin. Six sirloins from beef were dry-aged for 28 d, and the control group (n=6) was analyzed 2 d postmortem for this study. Dimensional changes (reduction of thickness and surface shrinkage) after cooking were significantly greater in the control group than the DA group, whereas the shear force of the DA group was significantly lower than that of the control. Effect of cooking on aggregation, hydrophobicity, and in vitro digestibility were significantly higher in the DA group than in the control. After cooking, the protein in DA sirloins was more oxidized than in the control samples. According to the sodium dodecyl sulfate-polyacrylamide gel electrophoresis result, the low molecular weight bands (below 17 kDa) increased in the DA group, finding that the protein characteristics of dry-aged beef was affected by cooking.

• Food Science of Animal Resources
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• v.36 no.2
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• pp.159-169
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• 2016

Animal muscles are stored for specific period (aging) at refrigerated temperatures, during and after which the living muscles start to convert into meat and thus, attain certain superior properties in the final product. Proteolysis, lipolysis, and oxidation are the major biochemical processes involved during the postmortem aging of meat that affect the tenderness, juiciness, and flavor, as well as sometimes may introduce certain undesirable traits. This review analyzes the role of pre- and post-mortem factors that are important for aging and their effect on the chemical and physical changes in the “dry- and wet-aged meat.” Thus, if the meat processing manufacturers optimize the effects of aging for specific muscles, the palatability, color, and the shelf life of the aged meat products could be significantly enhanced.

• Food Science of Animal Resources
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• v.39 no.3
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• pp.474-493
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• 2019

The aim of the study was to evaluate the effect of an early post-mortem low voltage electrical stimulation (ES) to localized part of carcasses [m. longissimus lumborum (LL) and m. biceps femoris (BF)] and determined the tenderness and flavor compounds of Hanwoo steers (n=16). Carcasses were stimulated within 30 min post-mortem for 60s using 60 volts and muscles aged 2 and 14 d. Degradation of Troponin-T were accelerated by ES and degraded little faster in BF muscle than LL. Level of free amino acid content of stimulated and aged muscles was significantly (p<0.05) greater than control for both muscles. Totally 63 volatile compounds were identified by using SPME-GC. The ES treatment significantly (p<0.05) affected the level of 20 volatile compounds of LL as well 15 volatiles in BF muscle along with total amounts of ketones, sulfur containing, pyrazines and furans. Low voltage ES could be applied to reduce the aging time and improve volatile flavor development by increasing important desirable volatile compounds such as 2-methylpyrazine, 2,5-dimethylpyrazines and 2-acetylthiazole etc. due to released free amino acids from protein degradation.

• Food Science of Animal Resources
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• v.43 no.3
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• pp.412-427
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• 2023

The effects of wet-aging using a commercial refrigerator (CR, 4℃) and a pulsed electric field refrigerator (PEFR, 0℃ and -1℃) on the quality of sous vide pork loin were analyzed. The moisture and fat contents, pH, CIE L^*, CIE b^*, chroma, and shear force of the wet-aged samples were lower than those of the raw meat samples, whereas the water holding capacity (WHC) was higher. The PEFR group showed higher pH, CIE b^*, chroma, and WHC and lower weight loss than the CR samples. Electronic nose analysis indicated that positive flavor compounds were induced whereas negative flavor compounds were inhibited in the PEFR group. Wet-aging increased the sourness, saltiness, and umami of sous vide pork loin; the PEFR 0℃ samples showed the highest umami. Sensory evaluation indicated that wet-aging improved the color of sous vide pork loin. The PEFR 0℃ samples were rated higher than the raw meat and CR samples for all sensory traits. In conclusion, sous vide after wet-aging using a PEFR improved the quality of pork loin.

• Journal of Animal Science and Technology
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• v.48 no.5
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• pp.671-682
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• 2006

This experiment was conducted to investigate the effects of dietary Ca levels and some feed additives such as isoflavone and casein phosphopeptide (CPP) on eggshell quality and hatching egg production in aged egg-type breeder hens. A total of three hundred and sixty, 56-week-old Hy-Line Brown breeder hens were divided into six groups and fed experimental diets of two levels of Ca (3.3% or 3.6%) either with addition of 0.2% isoflavone, 0.5% CPP or devoid of all for 5 weeks. There were no significant differences in laying performances and settable egg production among the groups. Significant increases (P<0.05) in eggshell strength were observed with increasing dietary Ca and addition of isoflavone, but not with addition of CPP. Fertility and hatchability were not influenced by dietary Ca and addition of isoflavone or CPP. The treatment had few significant effects on tibial proximal compositions and breaking strength. The concentrations of Ca, P, estrogen and calcitonin in serum were not affected by the dietary treatments. These results indicated that relatively high level of dietary Ca in combination with isoflavone had a beneficial effect on improving eggshell quality in aged egg-type breeder hens. But hatching egg production was not affected by dietary isoflavone or CPP.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1369-1379
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• 1999

To assess the food habits, nutrient intake and diet quality of preschool children aged 1 to 6 in Pusan by their meals and snacks, dietary survey was conducted with 176 subjects by a questionnaire and 24hr recall method. 63.1% of the subjects often skipped meals and 72.1% of those skipped breakfast in the main. 94.5% had snacks over once per day. The mean energy intake was 1406.4kcal, with 57.7% of energy intake being supplied by carbohydrate, 13.7% by protein, 28.6% by fat. 54.9%, 71.7% and 26.5% of intakes of protein, calcium and iron were supplied respectively by animal food. Most of iron intake came from plant origin. The percent of calcium intake from animal origin was low significantly in a group aged 4 to 6(p<0.05). The mean intakes of calcium, iron and niacin of total subjects were below Recommended Dietary Allo wance(RDA) for Koreans. The mean intakes of iron and niacin of a group aged 1 to 3 were below RDA as well as those of energy, caicium, vitamin B2 and niacin of the group aged 4 to 6. For calcium, iron, vitamin A, niacin and vitamin C, proportions of subjects with intake levels less than 75% of RDA were all over 36%. For most nutrients, proportions of subjects with intake levels less than 75% of RDA were higher in the group aged 4 to 6 than in the group aged 1 to 3. Nutrient adequacy ratios(NAR) were the lowest in iron in case of the group aged 1 to 3 and in calcium in case of the group aged 4 to 6. NAR of iron increased and that of vitamin B2 decreased significantly along increase age(p<0.05). The mean adequacy ratios(MAR) were 0.82 for total subjects, 0.83 for the group aged 1 to 3 and 0.80 for the group aged 4 to 6. The indexes of nutritional quality(INQ) of calcium, iron and niacin of the group aged 1 to 3 were below 1 as well as those of calcium, vitamin B2 and niacin of the group aged 4 to 6. Both of the age groups received 31.6~59.0% of daily intakes of energy, fat, calcium, phosphrous, vitamin B2 and vitamin C from snacks. So snacks clearly play an important role in dietary intake. Both of the NARs of most nutrients and MAR were higher in snacks than in three meals. The INQs of calcium and iron from three meals and those of iron, vitamin A, vitamin B1 and niacin from snacks of the group aged 1 to 3 were all below 1. The INQs of calcium and vitamin B2 from three meals and those of vitamin A and niacin from snacks of the group aged 4 to 6 were all below 1. In conclusion, nutritional characteristics were different between the two age groups. More attention should be paid to improve adequacy of nutrient intake through meals. And dietary management for snacks is needed especially in the group aged 1 to 3.

• Nutrition Research and Practice
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• v.6 no.6
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• pp.527-533
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• 2012

It is thought that calcium (Ca) and magnesium (Mg) may be related to mental disorders such as depression; however, there have been few studies investigating the association between Ca and Mg nutrition status with depression in middle-aged female adults. Study subjects in this study included 105 women between the ages of 41 and 57 years. The subjects were divided into three groups according to the Zung Self-rating Depression Scale (SDS) score: Group I (SDS score < 33 percentile; n = 32), Group II (33 percentile ${\leq}$ SDS score < 67 percentile; n = 37), and Group III (67 percentile ${\leq}$ SDS score; n = 36). Anthropometric measurements, dietary intake survey using 3-day dietary records, SDS questionnaire and measurement of serum Ca and Mg were obtained and analyzed. No differences were observed in Ca, plant Ca, and Mg intake among the three groups. However, animal Ca intake by Group III was 141.3 mg, which was significantly lower than 207.6 mg by Group I and 198.3 mg by Group II (P = 0.0345). There were no significant differences in serum levels of Ca, and Mg among the three groups. Correlation analysis indicated that the SDS score had negative correlations with Ca intake (r = -0.2927, P<0.01) and animal Ca (r = -0.3411, P<0.001) after adjusting for age, menopause and energy intake. In conclusion, dietary Ca and animal Ca had negative associations with SDS score among middle-aged Korean female adults. Additional analysis of factors related to the association of calcium and magnesium nutritional status and depression is necessary.

• Food Science of Animal Resources
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• v.38 no.2
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• pp.251-258
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• 2018

We investigated microbial and quality changes in wrap-packaged dry-aged beef after completion of aging and subsequent storage in a refrigerator. After 28 days of dry aging (temperature, $4^{\circ}C$; RH, approximately 75%; air flow velocity, 2.5 m/s), sirloins were trimmed, wrap-packaged, and stored at $4^{\circ}C$ for 7 days. Analyses of microbial growth, pH, volatile basic nitrogen (VBN), 2-thiobarbituric acid-reactive substance (TABRS), and instrumental color, myoglobin, and sensory evaluation were conducted on days 0, 3, 5, and 7. The results show that the number of total aerobic bacteria (TAB), yeast, and lactic acid bacteria increased with an increase in storage days, whereas no change in the growth of mold was observed during 7 days of storage. Based on the legal standard for TAB count, the estimated shelf-life of wrap-packaged dry-aged beef was predicted to be less than 12.2 days. However, the shelflife should be less than 6.3 days, considering the result of sensory quality (odor, taste, and overall acceptance). No significant change in visible appearance was also observed during 7 days of storage. The results suggest that the present quality indicators for meat spoilage (pH, VBN, and TBARS) should be re-considered for dry-aged beef, as its characteristics are different from those of fresh and/or wet-aged beef.

• Food Science of Animal Resources
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• v.39 no.2
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• pp.266-275
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• 2019

Although the production of dry-aged beef has been increasing, most purveyors are unaware of the changes in quality that ensue after completion of the aging period and do not adhere to specific guidelines for its packaging and storage. The objective of this study was to investigate the storage stability of vacuum-packaged dry-aged beef based on changes in microbial, physicochemical, and sensory properties during refrigeration at $4^{\circ}C$ for 21 d. The total aerobic bacterial count exceeded 6 Log CFU/g at approximately day 11 and significantly increased after day 14. Freshness indicators such as pH and volatile basic nitrogen content were acceptable until day 14 and 21, respectively. Based on the evaluation of overall sensory acceptability, the dry-aged beef was acceptable until 14 d without any sensory deterioration. Therefore, vacuum-packaged dry-aged beef could be stored for 11 d at $4^{\circ}C$ without any adverse effect on its microbial and sensory quality.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.4
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• pp.524-529
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• 2014

Two methods of feed preference trials were compared to evaluate the acceptability of 5 fresh foliages: Leucaena leucocephala, Moringa oleifera, Portulaca oleracea, Guazuma ulmifolia, and Brosimum alicastrum that was included as control. The evaluation included chemical analyses and forage intake by rabbits. The first method was a cafeteria trial; 12 California growing rabbits aged 8 wk, allocated in individual cages, were offered the five forage plants at the same time inside the cage, while in the second trial 60 California growing rabbits aged 8 wk, allocated individually, were randomly distributed into 5 experimental groups (n = 12/group); for each group just one forage species was offered at a time. The testing period for each method lasted for 7 d, preceded by one week of adaptation. The results showed that B. alicastrum and L. lecocephala were the most preferred forages while on the contrary G. ulmifolia was the least preferred one by rabbits. The results also revealed that the CV% value for the 2nd method (16.32%), which the tested forages were presented separately to rabbits, was lower and methodologically more acceptable than such value for the $1^{st}$ method (34.28%), which all forages were presented together at the same time. It can be concluded that a range of tropical forages were consumed in acceptable quantities by rabbits, suggesting that diets based on such forages with a concentrate supplement could be used successfully for rabbit production. However, growth performance studies are still needed before recommendations could be made on appropriate ration formulations for commercial use.