• Journal of Dairy Science and Biotechnology
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• 제29권1호
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• pp.59-63
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• 2011

This study was carried out to investigate the change of components which raw milk has during cold storage. General component content of raw milk (fat, protein, lactose, total solids) was decreased in proportion to the length of cold storage. The pH of raw milk was decreased in according to the length of cold storage. In electrophoresis images, ${\beta}$-casein which was one of the composition of raw milk was decreased as the period of cold storage extended on the other hand, the content of Ca and P in the serum casein was increased in accordance with the length of cold storage.

• 한국식품영양학회지
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• 제9권4호
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• pp.478-483
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• 1996

풋감을 30일간 저온저장(7$^{\circ}C$) 및 냉동저장(-2$0^{\circ}C$) 하면서 성분의 변화를 조사하였다. 수분, 단백질, 지질, 탄수화물 등의 일반성분은 저장방법이나 저장기간에 따른 변화가 없었으며, 조섬유 함량은 냉동저장 시는 거의 변화가 없었으나 냉장저장 시는 저장기간이 길어짐에 다라 약간씩 감소하였다. 폴리페놀 함량은 냉장, 냉동저장에서 모두 증가하였으나 냉동저장의 경우 증가폭이 매우 컸다. 총 펙틴 함량은 저장기간이 연장에 따라 감소하였고 수용성 펙틴 함량은 증가하였는데 냉동저장인 경우는 그 증가나 감소 정도가 매우 적었다. 탄닌 함량은 냉동저장 시는 거의 변하지 않았으나 냉장 저장한 경우는 크게 감소하였다.

• Fisheries and Aquatic Sciences
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• 제17권2호
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• pp.189-195
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• 2014

Headspace volatile compounds of cold-stored and freeze-dried Krill Eupausia superba were analyzed to investigate their flavor qualities using a system combining a dynamic headspace isolator, an automatic thermal desorber, and a gas chromatograph-mass-selective detector. Levels of oxidation products of polyunsaturated fatty acids such as aldehydes, alcohols, and ketones, which are known to give seafood a nasty smell because of their low flavor threshold values, increased during cold storage of krill. Notably, levels of 2-methylpropanal, 3-methylbutanal, 2-methylbutanal and 2-butanone increased during its storage. They can be considered index compounds of off-odor according to freshness degradation during storage. By contrast, in freeze-dried krill powder, levels of aldehydes, ketones, and aromatic compounds decreased rapidly. Only alcohols, which did not greatly affect the food flavor, were isolated in large amounts. It was confirmed that levels of oxidized compounds of krill increased during cold storage, but decreased in freeze-dried krill.

• 한국식품저장유통학회지
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• 제3권2호
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• pp.105-111
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• 1996

The conditions of cold stroage of Citrus unshiu Marc. var. okitsu produced in Cheju were investigated. The changes of peel moisture contents soluble solids, total sugar, vitamin C and density were slightly occured, and decay ratio was below 20% on keeping freshness relatively till late of March during cold storage. After thats decayed citrus fruits were increased gradually mainly from cold injury with lower temperature and high humidity. The loss of fruit weight, decrease of fruit hardness, and decrease of acid content were occured gradually during cold stroage. Because of the difficulty of long term storage for Citrus unshiu, the conditions and periods of cold storage would be determined after considering the physicochemical properties of fruits every year.

• 한국식품저장유통학회지
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• 제3권1호
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• pp.15-21
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• 1996

Physicochemical properties and the conditions of cold storage of kiyomi clangor(Citrus unshiu x sinensis) produced in Cheju were investigated. Firmness, edible part ratio, soluble solids, and acid content were decreased gradually with incurasing fruit size. Carbohydrates in juice were consisted of 65.12% sucrose, 19.65% fructose, and 15.23% glucose The main organic acrid In juice was 57.4% of citric acid, and others were lactic acid, malic acid, oxalic acid and fumaric acid, respectively. Weight loss were occured very. slowly to about 6% till late of May, but decayed fruits were occurred very slowly to about 6% till late of May, but decayed fruits were arisen to about 8% at 3$^{\circ}C$, and about 13% at 5$^{\circ}C$ of storage temperature. The changes of peel moisture content, soluble solids, total sugar, vitaamin C, and density of fruits were slightly occured during cold storage. Cold storage at 3$^{\circ}C$ and 87% relative humidity kept freshness of citrus fruits for a long-term without damage of cold injury.

• 한국식품조리과학회지
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• 제31권1호
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• pp.62-71
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• 2015

The purpose of this study was to evaluate the changes on the characteristics of the oxidative stability of Tenebrio molitor larvae during cold storage at $4^{\circ}C$. Pretreatment for T. molitor larvae was designed into three methods: raw (R), freeze-dried (F.D.), and pan-fried (P.F.). The water content of the raw sample (61.46%) was higher than those of other samples (F.D.: 5.02%, P.F.: 3.67%) and its high water content was expected to facilitate the oxidation of the raw sample. In our results, the peroxide value and the carbonyl value of all of the samples increased and the raw sample, after storage for 18 day, showed the highest value. The pan-fried sample had no significant increase in its lactic acid content, acid value, and thiobarbituric acid value; whereas those values were increased in the raw sample and the freeze-dried sample (p<0.05). The browning reaction was more progressed in the pan-fried sample than other samples at 0 day, but there was no significant change during the storage. The raw sample and the freeze-dried sample had their browning indexes increase with the increasing storage period (p<0.05). The pan-fried sample produced less oxidation products than the freeze-dried sample, indicating that the unheated sample was more susceptible to oxidation than the heated samples. In conclusion, heating treatment and low water content would be effective for improving the safety and stability of T. molitor larvae during cold storage.

• 한국포장학회지
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• 제30권2호
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• pp.141-147
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• 2024

스마트 농산물산지유통센터(APC) 도입에 따라 인력 작업 체계를 기계화하고, 양파 수확 작업의 저비용 및 고효율화와 장기 저장을 위해 그물망 대신 톤백(TB)과 와이어메쉬파레트(WMP)로 포장하고 적재하여 저장하는 동안 양파의 수분함량, 경도, 색도, 가용성 고형분 함량, 관능 검사 등 저장성을 비교 분석하였다. 대조군과 비교했을 때 TB와 WMP를 사용한 경우 수분함량, 가용성 고형분 함량, 경도, 색도에서 유의적 차이가 관찰되지 않았다. 외관 변화에 있어 TB는 CON과 비교 시 큰 차이가 없음을 확인하였다. 이는 그물망을 대체하여 TB로 양파를 포장하고 적재 및 저장하는 것이 양파 수확 작업 시 저비용 및 고효율화하고 스마트APC의 공정 개선에 효율적으로 적용할 수 있을 것으로 검토되었다.

• Journal of Microbiology
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• 제42권2호
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• pp.133-138
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• 2004

This study was aimed to determine the accumulation of free fatty acid by mesophilic lactic acid bac-teria (Lactococcus lactis subsp. lactis 1471, Lactococcus lactis subsp. cremoris 1000 and Lactobacillus casei 111) in cold-stored milk. According to the results, all cold-stored milks had higher acid degree val-ues than those of fresh milk. This phenomenon showed that a slight increase occurred in the accumulation of free fatty acids as a result of spontaneous lipolysis during cold storage. All lactic acid bacteria showed good performance in production of titratable acidity, which increased during fermentation of the milk (fresh and stored milks). Moreover, as the storage time was prolonged, more free fatty acid accumulation was obtained from the fermentation of the cold-stored milk by the investigated lactic acid bacteria. The control milk, which was without lactic acid bacteria, showed no change in the accumulation of free fatty acid during fermentation. From this result, it can be suggested that longer cold-storage time can induce higher free fatty acid accumulation in milk by lactic acid bacteria.

• 한국식품영양과학회지
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• 제26권5호
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• pp.886-891
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• 1997

The interrelation between physicochemical properties of milled rice and retrogradation of rice bread during cold storage was examined to compare the varietal difference in maintenance of rice bread quality. Twelve rice materials showed big varietal difference on physicochemical properties of rice starch such as amylose content(0.0~29.2%), gel consistency(20~98mm), and alkali digestion value(2.0~7.0). Rice bread made from milled rice of Jungwonbyeo, AC 27 and IRAT 177 exhibited soft texture and late retrogradation of rice bread during cold storage(4$^{\circ}C$). The amylose content of milled rice was closely associated with gel consistency negatively and with springiness of rice bread positively. The retrogradation of rice bread texture during cold storage was correlated with gel consistency of rice flour positively and with alkali digestion value of milled rice negatively.

• 한국축산식품학회지
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• 제27권3호
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• pp.314-319
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• 2007

본 연구는 도축과정 중 탕침법과 박피법의 탈모기법이 돈육질에 미치는 영향을 분석하고 이를 통해 생산된 식육의 냉장 저장성에 미치는 효과를 규명하고자 실시하였다. 탈모기법에 따른 온도체중과 등지방은 탕박을 실시한 처리구가 박피 처리구보다 높은 수치를 나타내었으며 등심 근의 온도에서도 등지방이 두껍고 도체중이 무거웠던 탕박 거세돈이 가장 높은 수치를 나타내었다. pH와 육색에서는 처리구 간 유의적인 차이를 보이지 않았지만 보수력의 경우는 탕박과 박피 처리에 따른 차이가 뚜렷하게 나타났으며 탕박법에 의해 탈모된 처리구에서 보수력이 저하되는 것으로 분석되었다. 냉장 저장 중 지방산패에 의한 TBA 측정의 변화를 분석한 결과 저장 1일 탕박 거세 돈의 경우가 가장 높게 나타났으나 다른 처리구와 더불어 대부분 신선한 상태를 유지하였다. Metmyoglobin의 경우 저장일 별 처리구 간 유의적인 차이를 보이지 않았으나 TBA측정치의 변화와 유사한 경향을 보였다. 총균수의 경우도 처리구 간 유의적 차이를 보이진 않았으며 저장 7일과 14일 사이에 급속하게 미생물이 증식하는 것으로 관찰되었고 14일 이후에는 완전 부패하였다.