• Korean Journal of Food Science and Technology
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• v.12 no.1
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• pp.34-40
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• 1980

In order to establish the frozen storage method of pork and contribute to the stabilization of pork price physicochemical changes and sensory evaluation of pork, stored at $-20^{\circ}C$ up to the period of 12 months, were analyzed every three months. The drip loss of frozen meat cuts was below 1% regardless of storage months. In the course of storage, pH of frozen half carcass rose a little, while that of meat cuts remained almost the same. WHC(water holding capacity) of frozen half carcass and meat cuts was in the range of $50{\sim}60\;and\;55{\sim}62%,$ respectively and VBN (volatile basic nitrogen) was about $11{\sim}18mg%,$ all of which did considerably change during the storage. TBA(thiobarbituric acid) value was not increased up to the 6th month of storage, but represented a considerable increase after the 9th month of storage, Both tenderness and juiciness of frozen pork were decreased after the 12th month of storage but the axxrptability of frozen pork to the consumers turned out fairly good.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.2
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• pp.114-118
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• 2001

In manufacturing process of Changran-Jeotgal, agitation with 10 rpm for 10 min/4 hrs of Changran-Jeotgal without released extract was carried out during the fermented process at $0\pm2^{\circ}C$ to shorten the fermentation period and uniform product quality, This step was called Improved process, while the step with release extract and standing fermentation was Conventional process. During 60 days of fermentation period, chemical, microbiological changes and sensory evaluation were examined, Brix, VBN and $NH_2-N$ were 27.4, $54.3\;mg\%\;and\;87.9 mg\%$ on 30th day in Improved process, respectively, but they were 27.1, $57.8\;mg\%\;and\;96.6\;mg\%$ on 50th day in Conventional process. The pH value was decreased from 7.0 to $\6.3\~6.5$ in both of them, The viable cell counts in Improved process was increased from $6.6\times10^3CFU/g\;to\;2.6\times10^6CFU/g$ during 30 days, in Conventional process, slowly increased from $5.8\times10^3CFU/g\;to\;1.9\times10^6CFU/g$ during 50 days. Sensory evaluation showed that products on 30th day in Improved process and products on 50th day in Conventional process were best favorable. From above results, we found that the fermentation with agitation shortened the fermentation period by 20 days compare to standing fermentation.

• Microbiology and Biotechnology Letters
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• v.11 no.1
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• pp.53-58
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• 1983

Sik-hae is a traditional Korean fermented fish product which is made from flat-fish, garlic, salt, red pepper and millet. The changes in chemical composition, pH, acidity and the contents of Amino-N, VBN, TMA and organic acids were investigated during the fermentation of Sik-hae. The changes in the microflora, enzyme activity and the sensory quality including textural characteristics were also evaluated. The changes in the contents of crude protein, crude fat and moisture during Sik-hae fermentation were negligible. The pH of the product tended to decrease in the course of fermentation and it showed the minimum value of 4.5 after 7 days of fermentation. On the other hand the acidity continued to increase up to 2300mg % by 4 weeks of fermentation. Lactic acid was the major organic acid. The content of Amino-N in sik-hae gradually increased up to 673.6mg % by 2 weeks of fermentation, and then slightly decreased. The content of VBN increased rapidly during the first 2 weeks of fermentation, while little changes in TMA content was observed. The number of proteolytic bacteria increased slightly for the first 2 weeks and then rapidly decreased. The number of yeast and acid forming bacteria increased rapidly from the 4th day to the 14th day of fermentation and then decreased. Both lipase and protease activities showed the maximum at the 11th day of fermentation. The texture softening of the fish occurred after 1 week of fermentation and the adhesiveness appeared after 2 weeks of fermentation. Summarizing these results, the optimum fermentation time for Sik-hae from flat fish were 2 weeks at 2$0^{\circ}C$ and the quality of the product could be kept for up to 4 weeks in refrigerator.

• Food Science of Animal Resources
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• v.24 no.1
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• pp.37-43
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• 2004

The "Ginseng Pork" produced by feeding ginseng by-products can be a compatible product in the sense of increasing pork consumption and developing functional food in the international pork market. This experiment was conducted to produce "Ginseng Pork" with emphasis on growth performance and meat quality. Experiments were conducted in which 30 Landrace heads were fed with bark of ginseng root(BGR) or heating extracts ginseng leaves and stem(HEG). WB-shear force was not different among the treatment groups until 15 days of ageing, but pork fed with the 6% BGR showed a higher shear force at 20 day of storage at 4$^{\circ}C$. Cooking loss showed lower value for the 9% BGR group compared with the control group. At 15 day, the 3% and 9% BGR groups showed lower cooking losses than control. Pork groups fed HEG showed a significantly(p<0.05) lower TBARS values after 5 days of storage. As for VBN analysis, the feeding groups of 9% BGR and 5.5% HEG had significantly lower values at 5 and 20 days when compared to the other treatment groups. It might be concluded that the accumulation of ginseng saponin in the pork resulted in retarding the ageing and inhibiting the oxidation.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.469-474
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• 2007

The aim of this study was to investigate the quality changes in Supraspinatus muscle of Hanwoo with different packaging methods, such as wrapped packaging (C), vacuum packaging (V) and modified atmosphere packaging (MA). These samples were stored for 25 days under $5^{\circ}C$. Each sample was evaluated for pH, volatile basic mitrogen (VBN) value, purge loss, hardness, meat color and microbial counts. From the results obtained, no significant differences were observed among treatments at the pH. The VBN values of MA were significantly lower than those of C. Also, MA was enhanced stability of meat color compared with other packaging methods during storage days. The purge loss was the most in the V samples, followed by the C and the MA was the lowest. Total bacteria counts of MA sample were significantly lower than those from C. Therefore, it has been concluded that MA could be used as an effective packaging since it extends the shelf life and improve the quality of Hanwoo supraspinatus m.

• Food Engineering Progress
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• v.14 no.3
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• pp.229-234
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• 2010

The applicability of a commercial enzymatic time-temperature integrator (TTI) for monitoring spoilage of ground beef was investigated under isothermal storage condition at different temperatures. The volatile basic nitrogen (VBN) value was used as a spoilage index for ground beef. The time taken to reach the spoilage of ground beef stored at 4, 10, 15, 20, and ${25^{\circ}C}$ were 168, 114, 60, 48, and 24 hrs, respectively. However, these quality losses of beef were not coincided with the endpoints of the three different C-type TTIs (C-1, C-4, and C-7). In order to match the TTI response to the quality loss of beef, some ingredients such as enzyme and substrate solutions were extracted from C-1TTI and remixed with different amount of them in the tubes to constitute the modified TTIs. The responses of the modified CM-1 TTI were very close to the quality loss of beef stored at 20 and ${25^{\circ}C}$, but not at other temperatures tested. The response of the other modified CM-2 TTI was only matched to the quality loss of beef stored at ${15^{\circ}C}$. Therefore, systematic kinetic studies of food spoilage and the TTI response are required to apply the TTI as a quality indicator for a specific food.

• Korean journal of food and cookery science
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• v.32 no.4
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• pp.390-399
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• 2016

Purpose: The objective of this study was to examine the effect of plant scale and cooking conditions on the quality characteristics of sausages during refrigerated storage. Methods: Sausages used in this study were classified into two groups: those submitted to $1^{st}$ cooked treatments and those submitted to $2^{nd}$ cooked treatments. The pH, volatile basic nitrogen (VBN), gas production ratio, and microorganisms were measured in triplicate. Results: The change of quality in the products was assessed every 7 days by measuring pH, VBN levels, total microbes, coliform bacteria, Escherichia coli, and pathogenic bacteria in the products. Pathogenic bacteria such as Staphylococcus aureus, Listeria monocytogenes, Clostridium perfringens, and E. coli were not detected in the sausages with $1^{st}$ cooked treatments. The results showed that the pH of the sausages decline as storage time increased. The pH value of the sausages with $2^{nd}$ cooked treatments changed gradually. VBN levels were generally lower in products with $2^{nd}$ cooked treatments than in those with $1^{st}$ cooked treatments, but they varied with the type of products. On the $35^{th}$ day, the number of total microbes ranged between 6.13-7.12 log CFU/g in products with $1^{st}$ cooked treatments and 3.44-6.92 log CFU/g in products with $2^{nd}$ cooked treatments, showing fewer bacteria in the latter products. Conclusions: $1^{st}$ cooked treatments were effective in microbial control, but $2^{nd}$ cooked treatments could prolong the shelf life of the sausages, indicating a need for differential management of each product.

• Korean Journal of Poultry Science
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• v.37 no.4
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• pp.405-413
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• 2010

This study was carried out to determine the effect of dietary supplementation of quercetin and methoxylated quercetin extracted from onions on oxidation of chicken thigh during cold storage. For 35 days, 1-day-old 320 broiler chicks (Ross) were divided into 8 groups and supplemented the diet; basal diet only (T1), T1 with antibiotics (T2), vitamin E 20 IU (T3), vitamin E 200 IU (T4), quercetin 20 ppm (T5), quercetin 200 ppm (T6), methoxylated quercetin 20 ppm (T7), methoxylated quercetin 200 ppm (T8). After slaughtering the broilers, thigh meats were collected and analyzed the oxidation stability during storage at $4^{\circ}C$ for 7 days. Volatile basic nitrogen (VBN) was ranged from 10.98~15.37 mg% until day 3 and quercetin 20 ppm (T5) significantly reduced (p<0.05) the VBN value of thigh as much as antibiotics treatment group (T2). The supplementation of quercetin at a 200 ppm level significantly reduced 2-thiobarbituric acid reactive substances value when compared with the control. Supplementation of 20 ppm quercetin also affected fatty acid composition of chicken thigh and resulted in increase of C18:1w9 and decrease of C18:2w6 on day 3. In microbes of chicken thigh during storage, supplementation of 20 ppm quercetin significantly reduced total microbes compare to control on day 7 (p<0.05). There was no effect on the number of coliforms in thigh with quercetin diet. From these results, the dietary supplementation of 20 ppm of quercetin may have effects on enhancing oxidation stability.

• Journal of Life Science
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• v.20 no.1
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• pp.55-59
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• 2010

In this study, the physicochemical and sensory characteristics of chicken press ham not fed with citrus byproduct (T0) and fed with citrus byproduct (T1) were compared. There was not a significant difference in moisture, crude protein, crude fat, crude ash, crude fiber, Hunter's $L^*$ (lightness), $a^*$ (redness), $b^*$ (yellowness), hardness, springiness, cohesiveness, gumminess, chewiness, shear force, water holding capacity and pH between T0 and T1. There was not a significant difference between T0 and T1 in terms of the chicken ham's VBN (volatile basic nitrogen) content for the first three weeks of storage, but after the fourth week of storage, the VBN content was 15.1 and 13.7 mg% for T0 and T1, respectively, which implies that feeding citrus byproduct significantly reduced the VBN content. There was not a significant difference between T0 and T1 in terms of the chicken press ham's TBARS (2-thiobarbituric acid reactive substances) value for the first two weeks of storage. However, the TBARS value was 0.31 and 0.22 mg malonaldehyde/kg for T0 and T1 during the third week of storage, and 0.49 and 0.32 mg malonaldehyde/kg for T0 and T1 during the fourth week of storage. There was not a significant difference between T0 and T1 in terms of the chicken press ham's TPC (total plate counts) for the first three weeks of storage, but after the fourth week of storage, the TPC was 4.96 and 4.72 log CFU/g for T0 and T1, respectively, which implies that T1 showed a significantly lower TPC than T0. T1 showed significantly higher aroma, taste, and palatability of the chicken press ham than T0, but there was a not significant difference in texture and juiciness between T0 and T1.

• Journal of Life Science
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• v.17 no.7 s.87
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• pp.964-969
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• 2007

This study was carried out to investigate the effects of addition of pork fat, olive oil and soybean oil on the quality and sensory of ground pork meat. The samples consisted of the ground pork meat containing 20% pork fat (GP-P), 20% olive oil (GP-O), and 20% soybean oil (GP-S). The chemical composition, surface color, fatty acid composition, water hold-ing capacity, pH, VBN content and TBARS value were determined for the ground pork meat as the quality characteristics, and the sensory score were also evaluated. The moisture, crude protein, crude fat and crude ash content were not different among the GP-P, GP-O and GP-S. The $L^{*}$(lighaess), $a^{*}$(redness) and $b^{*}$(yellowness) of /GP-P were higher than those of the GP-O and GP-S (p<0.05). Palmitic acid was the most abundant among saturated fatty acids, and palmitic acid content of GP-P (24.384%)was higher than that of the GP-O (15.611%) and GP-5 (14.423%). In case of unsaturated fatty acids, oleic acid of GP-P (43.773%) and GP-O (65.040%) were the highest, linoleic. acid for GP-5 (40.762) was the highest. The water holding capacity of GP-P was higher than that of the GP-0 and GP-5, the pH of GP-S was higher than that of the GP-P and GP-O, and the VBN content and TBARS value of GP-P was higher than that of the GP-O and GP-5 (p<0.05). The raw color of GP-0 and GP-S were higher than that of the GP-P (p<0.05), however the raw aroma was not different among the samples. In case of roasted ground pork meat, the aroma was not different among the samples, the taste, texture and palatability or GP-S were the highest among the samples, and the juiciness of GP-O and GP-S were higher than that of the GP-P(p<0.05).