• Food Science of Animal Resources
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• v.42 no.5
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• pp.816-832
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• 2022

To evaluate the effects of early postmortem vacuum packaging (VP) on meat quality during postmortem chilled storage, hot-boned lamb was vacuum-packaged at 1, 6, 12, 24, and 48 h postmortem and stored around 2℃ until 168 h postmortem, with lamb packaged in plastic wrap as the control (aerobic packaging). Intramuscular pH decline was delayed when lamb was vacuum packaged at 1, 6, and 12 h postmortem (p<0.05). The lamb vacuum-packaged at 1 h postmortem (VP-1h group) had significantly lower shear force values and purge losses accompanied by lower free thiol group values than other treatments during postmortem storage and was also higher in extractable calpain-1 activity by 6 h postmortem (p<0.05). Free thiol group concentrations were significantly higher after VP at 6 and 12 h postmortem (p<0.05). Packaging lamb under vacuum very early postmortem produced the lowest shear force and purge loss, likely by slowing heat loss and muscle temperature decline, implying that lamb quality is improved by VP when applied very early postmortem. This was at the expense of protein oxidation, which was unrelated to other meat quality measurements, most likely because potential contracture during hot boning confounded its impact. Further research is required to understand the implications of the interaction between protein oxidation, VP, and hot boning on the acceptability of lamb.

• Solar Energy
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• v.19 no.4
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• pp.33-43
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• 1999

The study on ice thermal storage system is to improve total system performance and increase the economical efficiency in actual all-conditioning facilities. To obtain the high charging and discharging efficiencies in ice thermal storage system, the improvement of thermal stratification is essential, therefore the process flow must be piston flow in the cylindrical type. With the relation of the aspect ratio(H/D) in the storage tank, the stratification is formed better as inlet flow rate is smaller. If the inlet and the outlet port are settled at the upside and downside of the storage tank, higher storage rate could be obtainable. In case that the flow directions inside the thermal storage tank are the upward flow in charging and the downward in discharging, thermal stratification is improved because the thermocline thickness is maitained thin and the degree of stratification increases respectively. In the charging process, in case of inlet flow rate the thermal stratification has a tendency to be improved with the lower flow rate and smaller temperature gradient in case of inlet temperature, the large temperature difference between inflowing water and storage water are influenced from the thermal conduction. The effect of the reference temperature difference is seen differently in comparison with the former study for chilled and hot water. In the discharging process, the thermal stratification is improved by the effect of the thermal stratification of the charging process.

• Journal of Sericultural and Entomological Science
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• v.28 no.2
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• pp.35-37
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• 1986

To reduce the number of rearing season required for preservation of multivoltine silkworms which do not produce diapause eggs, the optimal egg stage, temperature, and period of cold storage were examinede using hatchability as an indicator of viability. Multivoltine silkworm starains MR, SPT, and HM were used in the study. 1. The hatchability of multivoltine silkworm eggs (MR and STP) preserve at 5$^{\circ}C$ for 30 days was 80% for the eggs chilled from 2 days after oviposition but less 5% for those chilled from 7 days after ovipostion. 2. When 2 day-old eggs of multivoltine silkworm (HM) were preserved between -2.5$^{\circ}C$ to 7.5$^{\circ}C$ for 15 to 60 days, $0^{\circ}C$ and 2.5$^{\circ}C$ showed the highest hatchability with 91% at 30 days and 61% at 60 days storage, respectively. 3. From these results, it can be concluded that by preserving 2 day-old eggs at 2.5$^{\circ}C$ for 50 to 60 days, rearing seasons required for preservation of the multivoltine silkworm can be reduced to half per year.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.3
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• pp.211-219
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• 2014

To confirm the food quality and storage stability of commercial Korean kamaboko, we experimented with the composition and textural properties using various surimis and kamaboko products. We also investigated changes in protein digestibility and lipid oxidation of vacuum packed products under chilled storage at $4{\pm}1^{\circ}C$. Among the fish meatbased surimi, vegetable mixed surimi had the lowest protein content (23.73 %), as compared to other surimi (51.9-73.6%). Siginificant (P<0.05) differences in protein, lipid content and degree of fat oxidation were noted between the fried kamaboko products of three companies. Adhesiveness, springiness, cohesiveness, gumminess, chewiness and resilience were similar in all samples, but there were notable differences in hardness and fractuability between samples. In vitro protein digestibility and trypsin indigestible substrate (TIS) were not inversely proportional in fried kamaboko products. The protein digestibility (80.30%) of steamed vegetable mixed fried kamaboko was lower than that of other fried samples (84.9-86.2%). Computed protein efficiency ratio (C-PER) of companies A and C's fried kamaboko was 2.6 but company B's was 1.9. There was no noticeable change in thiobarbituric acid reactive substances (TBARs) or protein digestibility for any of the vacuum packed fried kamaboko during 30 days of chilled storage.

• Food Science of Animal Resources
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• v.18 no.4
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• pp.339-347
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• 1998

The effects of conjugated linoleic acid (CLA) in egg yolk on fatty acid composition and lipid oxidation during chilled storage (4$^{\circ}C$) were investigated. CLA was synthesized according to the method of alkali isomerization using safflower seed oil (SSO). A total of 250 hens (200 days of age) were fed control diet (commercial formula feed for han) or CLA-supplemented diet (1%, 2.5% and 5% CLA) or 5% SSO supplemented diet for 6 weeks, and eggs were collected for analysis of CLA, fatty acid compositons and lipid oxidation. Eggs from CLA-supplemented diets groups showed significantly (p＜0.05) higher CLA content compared to those of control group. The contents of linoleic, palmitic, and myristic acid were increased as well as CLA content by feeding a CLA-supplemented diet. However, the contents of oleic and arachidonic acids in egg yolks were decreased by dietary CLA supplementation. The pH of egg yolk increased by the levels of CLA during storage. The contents of CLA were not significantly (p＜0.05) changed during chilled storage for 28 days, whereas TBARS were significantly (p＜0.05) increased. It is suggested that lipid oxidation of egg yolk might be affected by the levels of CLA in egg yolk due to changes in fatty acid compositions.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.166-171
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• 2008

Abstracts Soybean sprouts which are a popular vegetable in Korea, are produced using the techniques of sous vide. The purpose of this study was to determine the effect of nisin and storage temperature on the microbiological and physicochemical qualities of sous vide processed soybean sprouts during storage in order to improve shelf-life and industrial applications. During storage of the cook-chilled soybean sprouts at $3^{\circ}C$, no development of mesophilic microorganisms was observed. However, at $10^{\circ}C$ storage without nisin, the number of mesophilic microorganisms increased markedly, whereas sprouts stored at the same temperature with nisin showed no observed increase. Psychrotrophic microorganisms, anaerobic microorganisms, and Bacillus cereus all showed similar trends. The ascorbic acid content, following the sequential heat processing of soybean sprouts through blanching and pasteurization decreased markedly during early storage, and stabilized thereafter. During storage, no major changes in the color or ascorbic acid content of samples at either temperature were observed. With regard to microbial and physicochemical qualities, the presences of nisin and storage temperature are important factors for extending shelf-life of soybean sprout.

• The Korean Journal of Food And Nutrition
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• v.18 no.3
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• pp.168-174
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• 2005

Various changes of physico-chemical characteristics of chilled plaice muscle during storage at $4^{\circ}C$ in vacuum and aerobic packaging methods were examined. As a storaging period become longer, Hunter L, a, b value changes slightely. However, no differences were observed between vacuum and aerobic packaging method. The hardness of plaice muscle after death was $2,232\;dyne/cm^2$. The hardness of vacuum packaged plaice muscle storaged for 4 days was similar to that of aerobic packaged plaice muscle storaged fur 14 days. MFI(Myofibrillar Fragmentation Index) of aerobic and vacuum packaged plaice muscle showed maximum value at storage for 4days and 7 days, respectively. Mg-ATPase activities of mypofibril were increased gradually both of all during storage days. But that of MF from aerobic packaging plaice muscle was higher than that of vacuum packaging plaice muscle.

• Korean Journal of Poultry Science
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• v.23 no.4
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• pp.203-207
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• 1996

This experiment was carried out to find out the effects of packing methods on shelf-life and hy-giene of breast and thigh meats in chicken. The carcass weights were about 1.6 kg per bird, and chilled by air spray method. The breast and thigh meats were packed by either vacuum or atmosphere packing methods. Samples were analyzed at 1, 4, 8, 12 and 16 wk after quick freezing at -45˚C for 35 min. Regardless of packing method. The thiobarbituric acid(TBA) values of thigh meats after 1 wk of storage were higher than those of breast meats. The TBA values of both treatments were increased as storage period extended. In addition, the TBA values of vacuum packed meats were lower than those of atmosphere packed meats. The VBN(volatile basic nitrogen) values, regardless of packing method, at 1 wk of storage were higher than those of breast meats. The VBN contents of breast and thigh meats after 16 wk of storage increased markedly, but failed to show significant difference between the two packaging methods. Total plate counts of breast and thigh meats were increased gradually as storage period extended, and the total plate count of breast meat was higher than that of thigh meat. The coliform bacteria were not detected until 16 wk after storage.

• Food Science of Animal Resources
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• v.33 no.4
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• pp.448-455
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• 2013

Proper storage of left-over meat in a household refrigerator is important for extending its shelf-life and assuring its safety until it is next used. Various fresh meat packaging methods were examined to determine their effects on the quality characteristics of pork loins during household storage at $5^{\circ}C$. The packaging methods include 1) wrapping in a polyethylene pouch (WP), 2) keeping in an air-tight plastic container (CP), and 3) using a household vacuum packaging machine (VP). The fastest increase in total aerobic bacteria during storage occurred in the WP samples, followed by the CP and VP samples. The count of Pseudomonas spp. was found to be lowest in the VP, and then the CP and WP samples. Enterobacteriaceae grew fastest in the WP samples, followed by the CP and VP samples. The WP samples also incurred the most significant increase in thiobarbituric acids and volatile basic nitrogen values over the storage period, as compared to the CP and VP samples. Off-odour at 30 min after opening the package, was first notable at day 11 in WP samples, but only at day 15 in the CP and VP samples. The colour also deteriorated earlier in the WP samples than in the CP and VP samples.

• Food Science of Animal Resources
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• v.24 no.1
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• pp.29-36
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• 2004

Changes in quality characteristics and shelf-life of two types of grill sausage manufactured by using pork hind leg and re-pasteurized after packaging were investigated during storage at 5$^{\circ}C$ and 10$^{\circ}C$ up to 30 days. The total aerobic plate counts(APC) of N rnberger style grill sausage(NGS) and vegetable added grill sausage(VGS) were initially 3.08 and 3.57 log$\sub$10/CFU/$\textrm{cm}^2$, respectively, and gradually increased during storage time. After 30 days, the APC of NGS stored at 5$^{\circ}C$ and 10$^{\circ}C$ maintained relatively low at the levels of 5.32 and 6.58 log$\sub$10/CFU/$\textrm{cm}^2$, respectively. However, the APC of VGS exceeded the level of 8 log$\sub$10/CFU/$\textrm{cm}^2$ after 30 days at 5$^{\circ}C$ and after 20 days at 10$^{\circ}C$. pH was decreased with storage period, however it tended to increase after 30 days. The values of TBA and VBN for both sausages tended to increase with storage time, and this trend was pronounced at 5$^{\circ}C$ rather than at 10$^{\circ}C$. The purge loss was apparently increased in the VGS compared to the NGS sample as the storage period extended. According to the sensory evaluation, the marketing values of grill sausages stored at 5$^{\circ}C$ and 10$^{\circ}C$ were maintained until day 20 for NGS and day 14 for VGS, respectively.