• Korean Journal of Food Science and Technology
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• v.42 no.6
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• pp.682-687
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• 2010

The effects of various coating materials (alginate, 0.3%; xanthan gum, 0.05%; chitosan, 0.8%) and storage temperatures (4, 12, $25^{\circ}C$) on the shelf-life of Lentinus edodes mushroom were investigated in terms of weight loss, color, polyphenoloxidase (PPO) activity, and texture profiles. Out of the three coating materials tested in this study, chitosan was effective in maintaining the color, PPO activity, and texture of the mushrooms during storage for 6 days at $12^{\circ}C$. Moreover, when stored at 4, 12, and $25^{\circ}C$ for 6 days, the chitosan spray-coated mushrooms stored at $4^{\circ}C$ had higher Lvalues and lower ${\Delta}E$. Also, lower temperature storage inhibited PPO activity in the mushrooms and prevented the loss of textural properties during storage. Therefore, the shelf-life of Lentinus edodes mushroom can be further extended two-fold by spray-coating with chitosan and storing at a lower temperature ($4^{\circ}C$).

• Horticultural Science & Technology
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• v.19 no.4
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• pp.526-529
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• 2001

The study was conducted to investigate quality changes of red pepper by different shelf temperatures after storage at $7^{\circ}C$ for 30 days. Red pepper fruits produced high volume of $C_2H_4$ and $CO_2$ when alternating temperatures exceeded $10^{\circ}C$. Total sugar contents were not different among all the treatments. In contrast, sucrose content decreased about half at higher shelf temperature conditions than at $7^{\circ}C$. Capsaicinoid content was not influenced by alternating temperature, but ascorbic acid content tended to decrease by high shelf temperature after storage at $7^{\circ}C$. Decay did not occur under $13^{\circ}C$, while it occurred in 22.2% of hits at $15^{\circ}C$ and 68.8% at room temperature, respectively. From this results, it is suggested that the optimum shelf temperature of red pepper after low temperature storage should be under $13^{\circ}C$ and that fruits of red pepper stored at $7^{\circ}C$ for 30 days could be sold within 10 days on the shelf.

• The Korean Journal of Food And Nutrition
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• v.28 no.3
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• pp.335-342
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• 2015

We conducted a study on mukeun (long-term fermented) kimchi ripened over one year in an attempt to develop an alternative salt and improve the quality of low-salt kimchi. However, few studies have focused on mukeun kimchi that has been fermented for a short time in different salinity conditions. Therefore, the aim of this study was to investigate the physicochemical characteristics that occur during the fermentation of mukeun kimchi samples produced with different conditions of salinity and fermentation temperature. Kimchi samples were produced at 3 different salinity levels: 1.6%, 2.4%, and 3.2%. Previous studies revealed that the optimum fermentation time at pH 4.1 was 128 hours at $18^{\circ}C$ and 417 hours at $12^{\circ}C$; furthermore, the samples were stored for 12 weeks under the condition of $-1^{\circ}C$ after fermentation. Total cell increased on week 0 of storage and decreased according to the storage period. Total cell was the highest at 3.2% salinity and had a high value at $18^{\circ}C$ temperature during the storage period. Based on the physiochemical results, mukeun kimchi at a salinity of 3.2% can be fermented for a short time, and low-salt kimchi at a salinity of 1.6% and fermented at $18^{\circ}C$, is similar to mukeun kimchi at 2.4% salinity.

• Food Engineering Progress
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• v.15 no.4
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• pp.311-317
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• 2011

Rice bread premix was prepared from rice flour and vital wheat gluten, and the changes in the premix properties were studied during storage at 5, 25 and $35^{\circ}C$ for 4 months. Optimum level of 14-17% vital gluten could be added to the rice bread premix. The pH, sedimentation value, and Pelshenke value of the rice bread premix decreased with increasing storage period, whereas water retention capacity (WRC) and alkaline water retention capacity (AWRC) increased with increasing storage temperature. Mixograph peak time increased with increasing storage temperature. Rapid Visco Analyser (RVA) peak viscosity and setback values increased with increasing storage temperature and period. Decreased loaf volume was observed at the rice bread prepared from the premix during storage, especially at higher temperatures. Crumb hardness of the rice bread prepared from the premix increased during 4-month storage period.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2004.11a
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• pp.35-36
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• 2004

A total of 1.200 eggs obtained from 312-day-old Hy-line Brown layer breeder hens and 319-day-old Hy-line Brown commercial layer hens (600 eggs obtained from each ones) were used to investigate the effects of storage period, storage temperature, and insemination of hens on the change of albumen height, Haugh unit (HU), albumen pH, shell strength, and yolk color. Eggs were stored up to 14 days after lay at $3\;^{\circ}C\;or\;10\;^{\circ}C$ and sampled one day after stored and then 24 hours interval. Longer periods of storage resulted in lower albumen height and HU at both storage temperatures, but in higher albumen pH. The eggs stored at $3\;^{\circ}C$ were generally higher in HU and lower in albumen pH than the ones stored at $10\;^{\circ}C$. There was no statistically difference although the eggs obtained from the non-inseminated-hens were slightly higher in albumen height and HU than the eggs obtained from the inseminated-hens. Whereas, the eggs obtained from the non-inseminated-hens in the albumen pH of eggs stored at $3\;^{\circ}C$ was significantly (P<0.05) higher than the ones obtained from the inseminated-hens, but the albumen pH of eggs stored at $10\;^{\circ}C$ did not differ each other. The mean shell strength of the eggs obtained from the inseminated-hens was significantly (P<0.05) stronger than that of the eggs obtained from the non-inseminated-hens at both storage temperatures. Albumen height and albumen pH were negatively correlated(P<0.01~0.001) in both inseminated and non-inseminated-hen's egg groups. The degree of yolk colors were not significantly changed overall of the experimental periods in both storage temperatures. The study suggests that the change of egg freshness such as albumen height and HU are relatively more associated with storage period and storage temperature than insemination or non-insemination of hens.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.6
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• pp.609-614
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• 1991

Thermal stability and quality change during storage of red pepper oleoresin were studied. Upon heat treatment, carotenoids in oleoresin from red pepper were more stable under nitrogen than air. In the thermal stabilities, the presence of air at $100^{\circ}C$ for 3 hours and 10 hours were 69.1% and 42.3%, respectively ; whereas, in the presence of nitrogen, 95.4% and 92.3%, respectively. In contrast, capsaicin was comparatively stable upon heat treatment in the presence of air. The retentions of capsaicin at $100^{\circ}C$ for 3 hours and 10 hours were 84.7% and 81.3% with air, those were 90.7% and 87.5% with nitrogen, respectively. Color appearance showed close relation to the stability of total carotenoids during 60 days storage at varying temperatures ; $5^{\circ}C,\;25^{\circ}C\;and\;40^{\circ}C$ were 69.4%, 48.0% and 35.1%, respectively. The degradation of total carotenoids during storage could be interpreted as a first order reaction. The activation energy obtained from the Arrhenius plot was 5.03 kcal/mole. Conversely, capsaicin was very stable under storage temperatures. More than 90% of capsaicin was remained upon completion of storage. In the mean time, pH of oleoresin was increased slightly as increasing storage temperatures.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.8-14
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• 1996

The effects of temperature variations during storage, pasteurization on the quality of orange juices were investigated. To evaluate the quality of orange juices pasteurized at 75, 85 and $95^{\circ}C$ for 15 sec, microbial and physicochemical measurements and sensory evaluations were conducted during storage at 10, 20 and $30^{\circ}C$ for 32days. Color(lightness) and contents of vitamin C and sucrose were not changed at $10^{\circ}C$, but decreased at $20^{\circ}C$ and $30^{\circ}C$ as the storage time was increased. The pasteurization temperature had a little effect on the color and the contents of vitamin C and sucrose. Furfural contents were apparently increased as the storage period extended, but the samples stored at $10^{\circ}C$ had less amounts than the others. On the other hand, the pasteurization temperature did not affect furfural accumulation. Furfural was produced as a result of the degradation of vitamin C and deterioration of the color. The PH values were not changed during the entire storage period, and microorganisms were not detected in most of the samples. The result of sensory evaluation indicated no taste difference between the control and the sample stored at $10^{\circ}C$, but the taste changes were recognized when the samples were stored over 24 and 20 days at $20^{\circ}C$ and $30^{\circ}C$, respectively. Therefore, the storage temperature affected the quality of orange juices more markedly than the pasteurization temperature, and the storage at lower temperature appears to reduce the deterioration of orange juices.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.134.1-134
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• 2003

저장 전 키토산과 칼슘 처리와 저장고 형태에 따른 온주밀감의 저장 중 품질특성을 검토하였다. 항균제로서 베프란(iminoctadime-triacetate) 2,000배 희석액, 키토산 1.5%에 0.5% CaCl$_2$를 혼합한 용액에 감귤을 충분히 침지하였다. 풍건시킨 후 26L인 플라스틱 컨테이너에 감귤을 12kg 정도씩 담아 3$0^{\circ}C$에서 24시간동안 저장전 처리를 하고, 상온저장과 내부온도 4$^{\circ}C$, 상대습도 87%를 기준으로 저장하였다. 저장고내의 온습도 편차가 적은 저장고에서 낮은 부패율이 나타내어, 감귤저장 중 온도관리가 중요함을 알 수 있었다. 중량감소, 껍질과 과육의 수분 함량은 저장 중 서서히 감소하였으며, 저온저장에서 감소 폭이 적었다. 산 함량의 감소는 저장 4개월 동안 15-18%이었다. 비타민 C는 저장 중 감소가 많아 장기간 저장으로 감귤품질이 떨어짐을 알 수 있었다. 유리아미노산은 23종이 검출되었다. isoleucine, leucine은 저장감귤에서 검출이 되지 않았으며, 이와 반대로 alanine은 90일간 저장한 감귤에서만 검출되었다. 품질유지가 위한 청견의 저장은 3개월까지로 판단된다.

• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.345-349
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• 1985

The textural properties of acorn flour gels were investigated with the variations in the concentraction, storage time and storage temperature by the use of Instron Universal Testing Machine. The experimental design was $3^3$ factorial experiment. TPA curves of acorn flour gels showed two sharp peaks in the first bite and no negative peak. The hardness and brittleness of acorn flour gels were very significantly affected by concentration, storage time and storage temperature. For the height difference between first peak and second peals, the main effects for concentration and storage temperature were very significant and the main effect for storage time was not negligible. For bend, the effect of concentration was more significant than the effect of storage temperature, and storage time effect was negligible. Springiness was affected only by the concentration.

• Applied Biological Chemistry
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• v.38 no.3
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• pp.232-238
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• 1995

Quality changes of high fructose corn syrups (HFCS) were investigated during storage at $-5{\sim}60^{\circ}C$. Color properties such as spectrophotometric properties, HMF and Hunter color value increased continuously during storage period. And the change was most evident as storage temperature and fructose content were elevated. High fructose corn syrups all showed flow behaviors as dilatant fluid and their viscosities increased slightly during storage. Content of fructose decreased, while glucose, maltose and oligosaccharide contents increased during storage. Especially, crystallization of what was observed below $13^{\circ}C$ during storage.