• Journal of Animal Science and Technology
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• v.46 no.5
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• pp.859-870
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• 2004

This study was conducted to investigate physico-chemical changes of pork prepared by Korean traditional 3 types seasoning such as soybean sauce(Tl); garlic sauce(T2); red pepper sauce(T3). The seasoned samples were aged at 0 ${\pm}$ $1^{\circ}C$ for 30 days. The results obtained were as follows; Salinity(%) and saccharinity(%) of sauce were significantly decreased(P<0.05) among the all treatments during aging periods, whereas fermented meats were significantly increased(P<0.05). pH of sauce and fermented meat were tended to increased as aging period. Water-Holding Capacity(WHC) and shear force of fermented meat increased(P<0.05) among the all treatments at 20 days of storage, and decreased after that period. In color, $L^* and b^* value of T3 were lower, while a^*$ value was higher than other treatments during aging period. Volatile Basic Nitrogen(YBN) value of all treatments were increased(P<0.05) after 20 days of storage. YBN value of T3 was significantly higher(P<0.05) compared with other treatments. Thiobarbituric Acid Reactive Substances(TBARS) was rapidly increased until 10 days of storage and somewhat decreased up to 20 days after 10 days in all treatments, it was re-increased after 20th days. T3 showed the highest TBARS among the all treatment groups. Total bacterial and Lactobacilli spp. were significantly increased(P<0.05) in all treatments at 10 days of storage and decreased after that period, however it tended to increased at 30 days of storage. In sensory evaluation, overall acceptability in all treatments were increased after 20 days of storage compared to initial storage and it score was similar thereafter.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.277-285
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• 2010

The objective of this study was to manufacture spent layer chicken meat products by natural freeze-drying. The spent layers of chickens that were slaughtered at 80 wk were obtained from a local slaughter house and separated into two halves of carcasses. The samples were divided into the following groups: 1) control (non-curing), 2) curing, and 3) curing with 2% trehalose before drying. The cured meats were placed at $2^{\circ}C$ for 7 d and then transferred to a natural drying spot located in Injae City, Gangwondo, Korea. The experiment was conducted from January to March in 2008. The average temperature, RH, and wind speed were $-1.5^{\circ}C$, 63%, and 1.8 m/sec, respectively. The cured treatments showed higher pH, lower Aw and lower shear force value compared with the control. Based on the results of TBARS (2-thiobarbituric acid reactive substances) level and volatile basic nitrogen value, lipid oxidation and protein deterioration were inhibited in curing treatments during drying. Trehalose acted as a humectant because it maintained a lower water activity despite the relatively higher moisture content during drying. The polyunsaturated fatty acids content and sensory attributes were higher in cured treatments than in the control during drying. Most of the bacterial counts in the treated groups were lower by 2 Log CFU/g after 1 mon of drying, and Salmonella spp. and Listeria spp. were not found in any treatment. There was also no microbial safety problem associated with dried meat products. Based on the results of this experiment, dried meat products could be manufactured from precured spent layer chickens by natural freeze-drying during winter.

• Korean Journal of Agricultural Science
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• v.9 no.1
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• pp.284-302
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• 1982

Development of protein resources as food has been a big issue especially in Southeast Asia region, and intake of protein is also insufficient in Korea. To cope with this shortage of protein resources and its improvement together with increased production of high nutritive animal protein, studies were carried out on feeding of Korean native goats. In the experiments were made absorption of carbohydrate and volatile fatty acid in miniature rumen, and absorption of amino acid in rumen as in vivo were conducted as part of studies on nutritional absorption in rumen. Those nutritional for improvement of feeding and management as described above are summarized as following. 1. According to the result of test on the nutritional absorption of native goat by means of miniature rumen method, absorption ratio of VFA measured at 0.5, 1 and 2 hours after injection of nutrition showed propionic acid 70-86%, acetic acid 74-87%, and lactic acid 76-89%. In the absorption of organic substances, ethyl alcohol of 0.5% showed 29-87% and lactic acid of 0.1M showed 12-27% of absorption ratio. 2. Result of absorption measurement in rumen from L-type free amino acid injection in the content of rumen vein showed lower rate at menthionine-free group compared to whole-egg amino acid injection in the content of rumen vein showed lower rate at methioine-free group compared to whole-egg amino acid group, and high absorption ratio was observed at methionine 3 times group and urea added group. Deficiency of methionine caused no change of the content in mucous membranes. 3. Absorption of amino acid in rumen muscular layer showed equal tendency as in the mucous membrane without exerting any influence of methionine deficiency. At the methionine3-times group, content of methionine and glutamine were increased by 14.7 and 4.4 times as compared to whole-egg amino acid group, an absorption ratio of glutamine, proline and valine were increased at urea added group. 4. In general, concentration of amino acid in rumen vein plasma was lower than in rumen mucous membrane and muscular layer. Absorption ratio of amino acid is decreased due to methionine deficiency, and tripling of methionine or urea adding caused increment of amino acid. Absorption pattern is thus varied depending on the composition of amino acid. 5. At the urea added group, content of ammonia-N, amino-N and urea were increased in rumen muscular layer. As the inside of goat's rumen was unable to clean thoroughly, investigation was made on remaining bacteria, however, variation of ammonia-N was affected by these bacterial content. 6. Variation in rumen structure by differential absorption of amino acid was observed by general microscope and fluorescent microscope. According to the result of observation in the methionine 3 times group, single cylinder epithelium of mucous membrane showed rather thin, and it was thick at urea added group though no significant differences existed among test groups in submucous membrane and muscular layer.