• Applied Biological Chemistry
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• v.36 no.3
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• pp.146-153
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• 1993

The changes in water uptake rate, cooking property, color of rice grain, gelatinization property of milled rice during storage were studied. The water uptake rate constant of milled rice during storage at $4{\sim}30^{\circ}C$ for 3 months decreased, which was more pronounced at elevated storage temperatures. The activation energy of water uptake was different below and above $25^{\circ}C$ of storage temperature. The activation energy after storage for 3 months below and above $25^{\circ}C$ was 608 and 1269 cal/mole, respectively. The rice grain became harder and the cooking time was prolonged by $3{\sim}8$ minutes upon storage. The cooking rate constant was linearly decreased as a function of storage time. The activation energy of cooking after 1 month of storage was 235 cal/mole, which was increased by 1.7 times after storage of 1.5 months and thereafter by 1.2 times with the increase of 0.5 month. There were no significant changes in color of milled rice grains during storage at $4^{\circ}C$, but the increase of b value was observed at higher temperatures. The Initial pasting temperature of rice flour remained essentially unchanged during storage, but the peak viscosity consistently increased with the increase of storage time and temperature. The gelatinization temperature of rice flour by differential scanning calorimetry was not changed but enthalpy of gelatinization was decreased during storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.1069-1075
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• 1999

The sterilization was attempted to improve the quality deterioration of soybean paste during its storage. For this experiment, soybean paste was sterilized at 80oC for 30 minutes and stored during 6 months at 15oC and 30oC, respectively. The total approximate composition contents were moisture 52.5%, crude protein 11.94%, crude fat 2.0%, amino nitrogen 413.3mg%, sodium chloride 11.61% and ash 15.5%. According to the increase of storage period, pH was decreased gradually because of the increase of organic acids by the metabolism of microorganisms and the acid accumulation by acid forming bacteria, but titratable acidity was increased during storage. Amino nitrogen was rapidly increased for the first one or two month storage period and maintained as the same level for the rest of them. Each amino acid contents of soybean paste, which were glutamic acid, tryptophan, proline, arginine, and aspartic acid, had much higher level than others. In color changes sterilized soybean paste(SSP) was much lower than that of raw ones(RSP). Hunter L and b values on the surface of soybean paste were decreased during storage, and the decreasing levels were higher at 30oC than at 15oC. Hunter a value, however, was increased a little in the initial storage, and thereafter it was decreased. Lactic acid bacteria, yeasts, and molds were disappeared completely by the sterilization. However, the bacteria of aerobes and anaerobes were not disappeared by this processing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.1
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• pp.13-20
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• 1990

Yu Ja cheong(Citron product) one of the traditional drinks was processed by a modified method to improve the quality,. Sugar(38%) and sorbitol(12%) were added as partially substi-tuted sugar and experimented about quality stability during storage at 20$\pm$2$^{\circ}C$ comparing with conventional 50% sugar added product. Chemical compositions of the acidity 40. 46mg% total Vitamin and 28.5mg% amino-N and pH was 3.7 During the storage pH reducing sugar and amino-N contents increased slightly while total acididty decreased slightly and reduced vitamin C occupied most part of total vitamin C after proessing was converted to oxidized vitamin C greatly at 70 days of storage. While L a and b values deceased in between modified one and conventional product. e value increased continually during storage {{{{ {C }_{16 { }:_{ } 0 } }}}} {{{{ {C }_{18 { }:_{ }0 } }}}} {{{{ {C}_{18 { }:_{ }1 } }}}} and {{{{ {C }_{18 { }:_{ }2 } }}}} contnts in fatty acid and citric acid itaconic acid malic acid and succinic acid in organic acid were the major componets in both products. Judging from the results of experiments during storage the quality of the modified product was compared quite well with that of vonventional one during storage.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.3
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• pp.428-432
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• 2009

40 goat kid ribcages were held for 7 days in storage conditions ($4^{\circ}C$) and used to determine the effects of three different packaging methods (atmospheric air, vacuum and modified atmosphere package (MAP) 10:70:20 mixture of $N_2:O_2:CO_2$) on meat quality of the chops. L* was affected by the packaging method being lighter than MAP chops. The coordinate a* significantly increased during storage time. For MAP-packed chops and those kept in atmospheric air, b* increased markedly during storage time whereas it remained unaffected throughout storage when in vacuum packages. Final pH values ranged from 5.6 to 5.8 and no effects were found for either storage time or packaging method. WHC means were lowest for the three packaging methods on day 7 of storage and highest on day 1. Storage time increased water loss in vacuum treatments. Trained panel colour acceptability was lower at 3, 5 and 7 days than on day 1 of storage for atmospheric air treatment and vacuum packaging, while for the MAP treatment average values on days 5 and 7 were lower than those observed on days 1 or 3. Trained panel odour was lower for atmospheric air and vacuum packages at 3, 5, and 7 days storage than at 1 day, while no differences were found in trained panel odour acceptability for MAP packages. With reference to consumers, the MAP proposed in the present study is the chosen method for storing goat meat, rather than vacuum or atmospheric air packaging.

• Journal of the East Asian Society of Dietary Life
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• v.5 no.2
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• pp.39-48
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• 1995

The effects of storage containers and storage temperatures on Kimchi quality were investigated. The results were summarized as follows : 1. Pabix, poly ethylene-back+plastic container, tupper-ware were much better than crock, stainless steel, and plastic container in keeping a Kimchi. However, there was no significant differences between containers in the sensory test for Kimchi. 2. Kimchi stored at 18$\pm$2$^{\circ}C$ was the most delicious, which revealed pH 4.30, acidity 0.45-0.50%, and salt concentration 3.10wt% in the 4th days after storage whereas sensory score for Kimchi quality was very low in the 12th days after storage. 3. pH in Kimchi stored at 5$^{\circ}C$ after fermentation at 18$\pm$2$^{\circ}C$ was slowly decreased as compared to the Kimchi stored at 18$\pm$2$^{\circ}C$, but texture score of Kimchi stored at -5$^{\circ}C$ or -8$0^{\circ}C$ after fermentation at 18$\pm$2$^{\circ}C$, but texture score of Kimchi stored at -5$^{\circ}C$ or -8$0^{\circ}C$ were compared to that of the Kimchi stored at 18$\pm$2$^{\circ}C$ after fermentation. 5. In the group of Kimchi stored at 1$0^{\circ}C$, immediately after picking it took 48days until the best conditions which were pH 4.30 and acidity 0.45-0.50% were matched. 6. The most promising method in keeping good taste and good quality of Kimchi was to store Kimchi at 5$^{\circ}C$ after 4days fermentation at 18$\pm$2$^{\circ}C$. And, for long period preservation of Kimchi, it took would be effective to store at -8$0^{\circ}C$ after fermentation at 18$\pm$2$^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.2
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• pp.62-65
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• 1983

As a new practical method for preserving freshness of fish, partially frozen storage has been reported to be useful in terms of K-value, TBA value, sensory evaluation etc. In order to develop a storage procedure to be used in place of cooled or frozen storage for the preservation of precooked fish food, partial freezing for up to two to three weeks was examined using baked mackerel. The criteria for evaluation were made according to the changes in volatile basic nitrogen (VBN), thiobarbituric acid (TBA) value, viable bacterial number, pH, color difference and sensory evaluation in fish muscle. The changes in TBA value of baked muscle during storage at $-3^{\circ}C$ differed slightly from those obserbed during cooled ($5^{\circ}C$) and frozen storage ($-20^{\circ}C$). Partial frozen storage ($-3^{\circ}C$) was effective in prolong an induction period of lipid oxidation during early storage. VBN of baked muscle tends to increase slowly while pH value was decrease during storage and there was no observed significant differences among three different storage condition. Viable bacterial number of the baked mackerel muscle stored at $-3^{\circ}C$ showed significantly less than that stored at $5^{\circ}C$, and similar to that stored at $-20^{\circ}C$ (the levels of $10^2/g$). Judging from the results of sensory evaluation and experimental data, partial frozen storage at $-3^{\circ}C$ seems to be effective as means of short-period preserving baked mackerel.

• Food Science of Animal Resources
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• v.28 no.1
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• pp.32-38
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• 2008

In order to expand the use of hog liver by the food industry, spreadable liver product was manufactured and quality changes were investigated depending on storage temperature at $-2^{\circ}C,\;5^{\circ}C\;and\;20^{\circ}C$ for 30 days. pH, thiobarbituric acid (TBA), volatile basic nitrogen (VBN), color, microbiological and sensory evaluation were carried out. Changes in pH values were not significantly different at different storage temperatures. TBA values were 0.6 mg MA/kg at $-2^{\circ}C$ after 30 days, 0.80 mg MA/kg at $5^{\circ}C$ after 21 days and showed 0.91 mg MA/kg at $20^{\circ}C$ after 14 days. The change in VBN content tended to increase during prolonged storage periods regardless of storage temperature. The product color tended to lighten over time, although there was no difference in a value of color during storage periods. Also, sensory evaluation results showed that the optimal storage temperature for the liver product was $5^{\circ}C$. The numbers of general bacteria increased to a level of 7.38 log CFU/g on storage 7 days in $20^{\circ}C$. This study showed that a viable spreadable liver product could be manufactured using hog liver and remains edible for at least 14 days when stored at temperatures below $5^{\circ}C$.

• Food Science of Animal Resources
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• v.21 no.2
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• pp.169-174
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• 2001

This study was carried out to investigate the effects on the quality and shelf-life of beef Hamburg patties. The patties composition, which used in the preparation of beef Hamburg patties is as the followings: Beef Tallow 20 Sodium 2(A), Beef Tallow 20 Sodium 2 Mugwort 1(B), Beef Tallow 20 Sodium 2 Mugwort 3(C) and were stored at -18$^{\circ}C$ for 30 days. The obtained results were summarized as the followings: The change of pH slightly decreased with increasing storage time. A(CON) decreased with increasing storage time, but the significant difference of pH changes were not shown between B(Mugwort 1%) and C(Mugwort 3%) group. The change of TBA values of all treatments increased during storage periods. The TBA value of A(CON) was the highest, and B(Mugwort 1%) was the lowest among groups. The change of VBN(volatile basic nitrogen) showed trends to increase during storage period in all groups. The number of microorganism increased during storage. The bacterial growth of C(Mugwort 3%) inhibited effectively, compared with the other groups. The number of E. coli decreased during storage periods. and the inhibitory effect of C(Mugwort 3%) was better than those of other groups.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.644-651
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• 2007

To establish the optimum conditions for storing buttercup squash, we examined the effectiveness of several storage methods and the quality of the squash under various storage conditions, including temperature (12 and $20^{\circ}C$) and relative humidity (20, 40, 60, and 80%). The spoiling rate of the squash was affected more by the storage temperature than the relative humidity, and the squash stored at $20^{\circ}C$ started to be deteriorated after 20 days of storage. At $20^{\circ}C$, soluble solid content gradually increased until 20 days of storage, and then it tended to decrease. The L-value had a tendency to increase with days of storage, and the a- and b-value also increased after 40 days. In addition, the color changes were great when the squash was stored at high temperature and high relative humidity. The total pectin content increased until 20 days at $20^{\circ}C$, and then it decreased, but less change was observed in the squash stored at $12^{\circ}C$. Overall, the results showed that storage at $20^{\circ}C$ after field curing resulted in excessive weight loss, color loss and poor eating quality, as well as a high level of decay (approximately 70%) after 40 days. However, the squash stored at $12^{\circ}C$ and 60% RH (relative humidity) showed less degreening and had a reduced level of decay, below 10%.

• Korean journal of food and cookery science
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• v.17 no.4
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• pp.391-398
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• 2001

This study was carried out to investigate the effects of storage temperature(5$\^{C}$ and 25$\^{C}$) and time(1, 24, 48 and 72hours) on the retrogradation characteristics of mungbean starch gels by using differential scanning calorimeter, rapid visco-analyzer, $\beta$-amylase method, X-ray diffractometer and scanning electron microscope. Endothermic peaks of gels stored at 5$\^{C}$ were shifted to the lower temperature than those stored at 25$\^{C}$ and endothermic enthalpy of gels stored at 5$\^{C}$ was greater than that stored at 25$\^{C}$. DSC thermograms showed that the retrogradation rate of gels stored at 5$\^{C}$ was higher than that shored at 25$\^{C}$. The pasting properties of the gels such as peak viscosity and final viscosity increased with increasing storage time except the gels stored at 25$\^{C}$ for 72 hours and this trend was more apparent at the storage temperature of 5$\^{C}$. The digestibility measured by $\beta$-amylase method decreased with increasing storage time and this trend was more apparent at the storage temperature of 5$\^{C}$. X-ray diffraction patterns of the gels stored at 5$\^{C}$ showed more distinct peak than those stored at 25$\^{C}$, but no difference was detected by the storage time. The microstucture of all the gels showed a well developed three dimensional network The network structure of the gels stored at 25$\^{C}$ formed a thick matrix after 72 hours and those stored at 5$\^{C}$ from the early stage of storage.