• Applied Biological Chemistry
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• 제35권1호
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• pp.36-41
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• 1992

면실유, 옥배유 및 채종유의 산패도를 신속하고 재현성 있게 측정하고자 $60^{\circ}C$ 및 $70^{\circ}C$로 저장한 식용유의 pentanal과 hexanal을 headspace 가스크로마토그라피 방법으로 분석하였고, 그 결과를 관능검사 결과와 상관분석을 실시하였다. Headspace 가스크로마토그라피 방법에서 휘발성 산화생성물의 포집 및 용출은 cold trap-thermal desorption 방법으로 실시하였으며, GC 주입부에 들어가는 splitless mode glass liner insert에 Tenax GC를 충전하여 사용하였다. 23종의 휘발성 산화생성물이 gas chromatography 및 gas chromatography-mass spectrometry에 의하여 검출되었으며, 저장 기간에 따른 pentanal과 hexanal 함량 변화와 관능검사에 의한 산패취 측정 결과의 상관분석을 실시한 결과, pentana(PE), hexanal(HE) 및 log{PE) log(HE) $log(PE){\times}log(HE)$의 세 가지를 변수로 한 회귀식의 상관계수의 값이 각각 0.831, 0.866 및 0.896으로 다같이 높을 값을 보였다. 따라서 headspace 가스크로마토그라피를 이용하여 면실유, 옥배유 및 채종유의 휘발성 산화생성물 중 pentanal과 hexanal을 분석하면 각각의 식용유의 산패도를 객관적으로 평가할 수 있음을 알 수 있었다.

• 한국식품영양과학회지
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• 제24권6호
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• pp.925-931
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• 1995

Cheddar, Emmentaler, Parmesan 그리고 Roquefort 치즈 등 자연 숙성 치즈와 지방 분해효소를 첨가하여 발효시킨 뒤 치즈향 농축물의 휘발성 향기 성분을 GC 및 관능적 분석을 통하여 비교하였다. 저급지방산이 그 특유의 향미를 나타내는데 가장 큰 영향을 미치는 성분으로 알려진 Parmesan 치즈향 농축물과 향미와 주성분으로 알려진 Cheddar 치즈향 농축물은 그 함량이 다른 시료 보다 10배 이상 높게 나타났따. 또한 메틸 케톤이 그 독특한 풍미의 결정적 온도가 되는 Roquefort 치즈의 경우는 제조시 lipase 및 P. roqueforti의 첨가로 메틸 케톤의 생성을 촉진시켜준 Roquefort 향 농축물의 함량이 월등히 높았다. 관능적 특성 차이를 비교한 결과 Cheddar, Emmentaler 그리고 Parmesan 치즈향 농축물이 sharpness, rancidity, soapy의 강도가 자연치즈 보다 유의성 있게 높았다. 반면, Roquefort 향 농축물에 있어서는 acidity, fruitness 등이 유의성 있게 높게 나타났다. GC profile과 관능적 특성과의 상관관계는 free fatty acid와 sharpness, rancidity, soap는 각각 0.8239, 0.8918, 0.7503 그리고 methyl ketone과 acidity, fruitness는 각기 0.9284, 09659의 높은 상관계수를 보였다.

• 한국식생활문화학회지
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• 제21권6호
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• pp.679-684
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• 2006

In this experiment, I used three samples of oils. The oils that I used were hydrated soybean oil, pure soybean oil and regular soybean oil. The group of rice was fried in the each sample of oil that had not been used for a few seconds. Rice was used after frying at 230-235$^{\circ}C$ every four hours terms and total frying hours was 12 hours. The hydrated soybean oils was least affected in rancidity. The other two oils were more affected in rancidity than the hydrated soybean oil. However, the trans fatty acid in hydrated soybean oil was 36.5%. The diameter of the poped rice that was fried in pure soybean oil and regular soybean oil that had been used 12 for hours was reduced while the diameter of the popped rice fried in the hydrated soybean oil was not reduced. Also, the groups of rice fried in the pure and the regular soybean oil that had been used for 12 hours reduced the hardness in rice while the group that fried in the hydrated soybean oil at the 12th hour kept the hardness well. In sensory evaluation, rancidity order was found apparently in the pure soybean oil that had been used for 12 hour and in the regular soybean oil that have been used for eight hours and 12 hours. Only the hydrated soybean oil did not have distinctive rancidity order at all. The degree of the crispiness was reduced in the pure soybean oil and in the regular soybean oil at 12th hour frying. However, the hydrated soybean oil preserved the crispiness well until the end of 12 hours of frying. In overall preference test, the pure and regular soybean oil that had been used for 12 hour were not preferable. In conclusion, I found that the group fried in the hydrated soybean oil was better in every evaluation than the groups fried in the pure soybean oil and in regular soybean oil. The hydrated Soybean oil may be better to be used in food manufacturing if the trans fatty acid in the hydrated soybean oil can be reduced.

• 한국응용과학기술학회지
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• 제2권1호
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• pp.19-23
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• 1985

In order to know the quality changes of the fat and oil foods packed in plastics film by the sunlight, we examined the sunlight transmitting rate by the kind of films and measured the acid value and peroxide value according to it. The results obtained were as follows : 1. The sunlight transmitting rate of various films was explained especial permeability under the wavelength of less than 300nm, but it marked a regular form under that of more than 30nm. 2. The vacuum evaporation film with aluminum on the polyester shuts off most of the sunlight, therefore, it has the best effect that keeps the fats and oils off rancidity. 3. The sunlight transmitting rate of the white color printing film drops about 80% as compared with not printing. 4. The preventive power against the rancidity of fats and oils is PET/Al, PET, PE, nylon and OPP film in that order. The changes of peroxide value and acid value were approximately the same as that of the sunlight transmitting rate.

• 환경위생공학
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• 제4권1호
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• pp.29-36
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• 1989

The purpose of this investigation was performed for chemical values related to rancidity of fat and oils extracted from deep-frying food in Seoul. The samples were collected according to kinds of fat and oils, sampling sites and food stuffs for frying. The results were as follows 1. The most used frying oils were rice bran oil $(37.0\%)$ and shortening $(29.6\%)$, followed by rapeseed oil $(14.8\%)$. 2. The chemical values related to rancidity of fat and oils extracted from deep-frying foods were the next on average. Acid value-1.42, peoxide value-39.82, dinitrophenyl hydrazine value-16.73 thiobarbituric acid value-0.263. However the highest value among oils was showed in rice bran oil and the lowest value was shortening. 3. For the classification of sampling sites, acid value and peroxide value of samples of the markets were found higher than them of environs of school and roadside, and the differences between them were significant (P> 0.01), while dinitrophenyl hydrazine value and thiobar bituric acid value were not showed the significant differences. 4. For the classification of foodstuffs for frying, there were not recognized significant differences among all kinds of them.

• 한국포장학회지
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• 제21권1호
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• pp.41-47
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• 2015

본 연구에서는 현미의 산패를 방지하기 위한 향낭을 개발하고, 이를 실제 현미포장에 적용하여 그 효과를 알아보고자 하였다. 이를 위해 항산화 활성을 가지는 것으로 확인된 allyl mercaptan으로 향낭을, 산소제거능이 있는 sodium L-ascorbate를 주원료로 이용해 산소제거능 향낭을 제조하여 현미포장에 적용하였다. 현미포장 내부에 allyl mercaptan 향낭 또는 산소제거능 향낭을 넣은 후 4주간의 저장기간 동안 1주일 간격으로 산가와 과산화물가를 측정함으로써 현미의 산화안정성을 살펴보았다. 그 결과, sodium L-ascorbate를 기반으로 한 산소제거능 향낭은 무처리구와 비교하여 유의적인 산패 억제 효과를 보였다. 이는 시판중인 철계 산소제거제와 유사한 성능이었다. 그러나 allyl mercaptan 향낭은 현미의 산패를 억제하는데 별다른 효과가 없는 것으로 확인되었다.

• 한국식품영양학회지
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• 제13권4호
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• pp.360-364
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• 2000

유지에 존재하는 linoleic acid의 전기화학적 산화/환원으로부터 속도론적 인자를 예측하고, 시간 변화에 대한 산패 정도를 조사하였다. Linoleic acid의 전기 화학적 산화환원 반응은 비가역적이고, 확산지배적으로 진행됨을 알 수 있고, 주사속도에 따른 결과로부터 확산계수 $D_{o}$ 는 2.61$\times$$10^{-6}$이고, 속도상수 $K^{o}$ 는 9.79$\times$$10^{-11}$로 주어짐을 예측하였다. 또한 linoleic acid의 산화반응 영역과 환원반응 영역에서 작업전극의 선택도가 달라짐을 볼 수 있다. 대기중 방치시간에 따른 시험 결과 방치한 지 4일을 전후로 산화 peak가 최대값으로 주어졌다. 특정 Peak에서 일정전위 전기분해 한 후 전기분해 생성물을 분석한 결과 carbonyl group이 생성됨을 예측할 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권3호
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• pp.420-425
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• 2008

The storage of rice polishing (RP) with and without addition of antioxidant for sixteen weeks and its effect on rancidity and metabolizable energy values during the summer season was determined. Fifteen Single Comb White Leghorn cockerels of approximately uniform age and weight were procured and kept in metabolic cages under standard feeding and management practices. Five force feeding trials were conducted. In the first trial, fresh RP with 0 weeks of storage (diet 1 and 2) was used followed by four feeding trials with 4 (diet 3, 4), 8 (diet 5, 6), 12 (diet 7, 8), and 16 (diet 9, 10) weeks of storage of RP. The same birds were used in all trails. The birds were fasted for a period of 21 h, followed by force feeding of 20 g of RP with and without antioxidant for all storage periods. The control/fasting group was also maintained to measure endogenous fecal losses. Excreta were collected after 48 h for the determination of AME and TME values of RP. Along with the biological trials, laboratory assay of the RP stored with and without antioxidant was conducted to measure the extent of rancidity in terms of Thiobarbituric acid value (TBA). The TBA values were affected (p<0.05) by storage period and the values increased when the storage period increased from 4 to 16 weeks. However, the TBA values were significantly reduced (p<0.05) when RP was stored after addition of antioxidant when compared with the values obtained from RP stored without antioxidant (diet 3 vs. 4, 5 vs. 6, 7 vs. 8, and 9 vs. 10). The AME MJ/kg and TME MJ/kg values of RP were neither affected by increase in storage period nor addition of antioxidant. The findings of this study revealed that there was no effect of rancidity and storage time on the nutritive value, AME or TME of RP in poultry. However, TBA values were increased with the increase in storage period.

• 한국식품조리과학회지
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• 제11권5호
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• pp.494-502
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• 1995

The study was conducted to evaluate the characteristics of Nuhbiani qualities with the different cooking, reheating methods and storage conditions. Cooking and reheating methods were used with pan, microwave and their combinations. Precooked samples were stored for 0, 1, 4, 7, 15 days in the refrigerator and for 15, 30 days in the freezer. TBA value, shear value by rheometer and sensory attributes in rancidity, hardness, juiciness and overall acceptability were measured. There was no significant difference between cooking, reheating methods in TBA values. Lower values in TBA were noted in the Nuhbiani of frozen storage as compared with that of refrigerated storage. There is a tendency that TBA values were increased as the storage time extended during the refrigeration. Shear values were more increased by microwave cooking and microwave reheating than other methods showing harder texture. Results from sensory evaluation of rancidity, hardness, juiciness and overall acceptability show that there were no significant differences between storage methods, among storage periods and cooking, reheating methods.

• 센서학회지
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• 제23권5호
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• pp.320-325
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• 2014

Volatile flavor compounds from milk were analyzed and identified by using the analysis methods of headspace solid phase microextraction gas chromatography/mass spectrometry (HSPME-GC/MS) and electronic nose (E-Nose) system. About 30 volatile compounds were identified by HSPME-GC/MS for the fresh and off-flavor milk samples. Also, the correlation between rancidity and ageing days of milk was obtained by the aid of principal component analysis algorithm. It shows that the E-Nose system can identify the various types of milk flavor. These results imply that the analysis method based on the E-nose system can apply to the quality control of milk flavor and the rancidity.