• Food Science and Preservation
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• v.19 no.5
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• pp.639-644
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• 2012

The rancidity of soybean (Glycine max L.) from Yeonhaeju, called "Bazaz", in powder forms was evaluated through a fluorescence spectrum test (FST). The results from the FST were validated by comparing the TBA and acid values. Soybean powders were stored in 25, and $90^{\circ}C$ for 20 days. The maximum excitation and maximum emission of fluorescent compounds generated from the soybean powder during storage were observed at the 360 nm and 430-440 nm wavelengths, respectively. The mean particle size of soybean powder was maintained at $40{\mu}m$ to avoid the dependence of the reaction area during measurement. According to the FST results, lipid oxidation did not actively progress during storage at $25^{\circ}C$. The fluorescence intensity (FI) from FST on the first day of storage was not significantly different from that on the last day of storage (day 20; p < 0.05), but the FI dramatically increased at $90^{\circ}C$. A smooth increase was observed in the initial stage; then, after 11 days of storage, the FI value increased by nearly 100% compared to that on the first day. The FI values were compared with TBA and acid values that were measured under the same storage conditions. All the values at $25^{\circ}C$ showed similar patterns during storage, but at $90^{\circ}C$, the FI and acid values showed similar patterns but the TBA decreased after reaching the maximum values on storage day 12. The results demonstrated that FST may be useful for measuring the rancidity of the powder form of soybean because it does not require extraction to measure the rancidity.

• Korean Journal of Poultry Science
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• v.20 no.3
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• pp.115-123
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• 1993

Mechanically deboned chicken meat(MDCM ) from necks and backs was blended with 0.1% oleoresin rosemary, 0.1% oleoresin sage and 0.05% rosemary combined with 0.05% sage to evaluate retardation of oxidative rancidity during storage at$3^{\circ}C$ and $-25^{\circ}C$, respectively. 1. Moisture content of MDCM was 66.3%. protein 17.6%, fat 15.0% and ash 1.10%. Several types of bone particles such as angular and needle like shape in MDCM were observed by light microscope. 2. Lipid oxidation of MDCM started to increase after 2 day and increase rapidly after 6 day of storage at $3^{\circ}C$. Oleoresin sage and rosemary apparently retarded oxidative rancidity of MDCM during refrigerated and frozen storage, TBA and total carbonyl values demonstrated that sage was more effective antioxidant than rosemary, and sage /rosemary combination was the most effective antioxidant among them. 3. The oxidative rancidity of MDCM apparently accelerated after 50 days of storage at $-25^{\circ}C$. The addition of oleoresin sage and rosemary inhibited oxidizing changes stored for 100 days at -$25^{\circ}C$.

• Preventive Nutrition and Food Science
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• v.7 no.3
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• pp.255-260
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• 2002

Yukwa is a popular Korean traditional fried rice snack. The high fat content and porous structure of Yukwa cause it to rapidly become rancid, presenting difficult challenges for commercial distribution. In this study, an-tioxidant activities of green tea extracts (GTE) were evaluated in Yukwa fried in soybean oil (SBO), rice bran oil (RBO) and winterized rice bran oil (WRBO) during storage at 4$0^{\circ}C$ for 12 weeks. Lipid oxidation of Yukwa was determined by acid value (AV), peroxide value (POV), p-anisidine value(AnV), totox value and sensory evaluation. The addition of GTE to the oils reduced the increases in AV, POV, AnV, and totox. Totox increased most vapidly in Yukwa fried in SBO, fellowed by RBO>WRBO>SBO+200 ppm GTE>RBO+200 ppm GTE > WRBO + 200 ppm GTE (p<0.05). Sensory evaluation revealed that the addition of 200 ppm GTE delays rancidity in Yukwa by 7~8 weeks; providing compelling evidence that GTE is an effective antioxidant for Yukwa.

• Journal of the Korean Society of Food Culture
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• v.20 no.1
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• pp.103-112
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• 2005

The objective of this study was to clarify the effect of addition of green tea powder(0%, 2%, 4%, 6%, 8%) to Yackwa on quality and preservation. Addition of 4% green tea powder turned out to give positive effect on expansion. In test of physical characters, addition of green tea powder had a tendency to lower hardness, cohesiveness, springness and gumminess but to enhance brittleness. Considering the rancidity of oil within Yackwa, addition of green tea powder tended to show lower acid value and peroxide value than non-added treatment but its difference was slight. At the sensory test, surface color, bitterness and green tea flavor were strong but sweet and savory taste weak when green team powder was added(p<0.05). Overall quality appeared to have improved to 5.55 points which is compared to non-addition when the powder was added 4%(p<0.05). In conclusion, 4% addition of green tea powder would be the usefull method to enhance preference and quality of Yackwa.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.4
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• pp.213-216
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• 1975

Yellow sea bream contains comparatively larger amount of fat among white muscle fishes, so that rancidity might easily occur during drying and storage. For the purpose of the protection of rancidity, the effect of some antioxidants was studied when yellow sea bream was sun-dried after dipping in the solutions and packed in PVC film$0.3mm\times12cm\times30cm $ for storage at room temperature. The inhibitory effect of additives was in order of Tenox-II, BHA, Sustane and NDGA, while EDTA, potassium sorbate, CTC and $\alpha-naphthylamine$ were ineffective. The results suggest that the treatment of $0.1\%$ Tenox-II solution and packing in PVC film is better condition to improve the quality of product and during drying and storage.

• The Korean Journal of Food And Nutrition
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• v.21 no.4
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• pp.477-484
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• 2008

The Pacific saury, Cololabis saira Kwamaegi, is a traditional local food of the Eastern sea area, centered around Pohang. It is well-recognized as being both tasty and nutritious. Nevertheless, bacterial contamination, excessive dryness, and compositional changes render this fish edible only during the winter months. Thus, to improve its storage capabilities, this study assessed the effects of storage material, type, temperature, and duration on compositional changes in Kwamaegi. The assessed samples were Kwamaegi which had been naturally dried for 15 days. The storage materials included an A-film, a self- developed multi-film made of polyethylene, polyamide, EVOH, and polyethylene, and a B-film made of polyethylene, nylon, polyethylene, nylon, and polyethylene. The B films were utilized after pressing and lamination. The storage types included one whole fish(1G), or 2 divided fish(2G), to increase eating convenience. The 2G type was the muscle portion divided vertically after discarding the jowl, skin, and internal organs. The storage temperatures were 0, -15 and $-30^{\circ}C$, and the storage durations were 2, 4, and 6 months. Among the lipid rancidities, acid value and peroxide value showed the highest level of initial rancidity at a storage temperature of $0^{\circ}C$ for 2 months. We noted no significant differences between storage materials. The lower the storage temperatures, the less acid and peroxide were generated. Between the storage types, 1G evidenced lower less acid values than 2G. The TBA values revealed a dramatic increase at a storage temperature of $0^{\circ}C$ for 2 months, whereas this rapid progress was not observed at storage temperatures of -15 and $-30^{\circ}C$. Along with the acid value and peroxide value, the samples stored at 0, -15 and $-30^{\circ}C$ evidenced significantly lower TBA values. The B-film evidenced a slightly lower TBA value than was observed in the A-film, but no significant differences were observed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.11
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• pp.1623-1630
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• 2011

The effects of addition of citrus peel powders (C 0, 0.5, 1 & 2%), dried Lentinus edodes powders (L 0, 0.5, 1 & 2%), and their combination (C-L) on the chemical, sensory and textural properties of pork sausages were studied. Addition of 0.5, 1 or 2% C, L, and C-L all significantly decreased moisture content, pH, and color a-values of sausage samples, whereas ash content and color b-value were increased (p<0.05). C, L, and C-L did not affect protein, fat, carbohydrates contents or texture characteristics. Sensory evaluation was performed by multivariate data analysis, namely principal component analysis (PCA). Eighty-two percent total variation was observed in the main structured information among the test groups: the first (PC1) and second (PC2) components of variation were 59 and 23%, respectively. Eight parameters (sweet flavor, pork aroma, bitterness, rancidity, salty flavor, color, sour flavor and citrus aroma) were utilized to describe the main sensory characteristic of the sausages. Addition of 0.5, 1 & 2% citrus peel was obviously correlated with PC1 (salty flavor, sour flavor and citrus aroma, pork aroma, and sweet flavor and rancidity), whereas addition of 0.5 & 1% Lentinus edodes was related with PC2 (aroma and rancidity).

• Korean Journal of Food Science and Technology
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• v.15 no.1
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• pp.6-11
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• 1983

The long-term storability of home-made dry sausage and ham in terms of peroxide value and thiobarbituric acid value, the effects of nitrite and NaCl contents on the deterioration of the products and the public acceptance of dry ham were studied. The results of this study are as follows: 1. Because the storability of the dried meat products is mainly affected by the fat rancidity of the fat content, POV of 10 was assumed the critical point of storability. The sample dry sausage used in this experiment has lost its storability within a ripening period of 5 weeks. And dry ham was lost its peculiar relish within 50 days. 2. The variations of the NaCl contents of the dry products were reflected in the ripening process. The correlation coefficient between the variations of the NaCl contents and the decrease in the weight of the dry ham was 0.85. 3. The survey of public taste for dry ham was conducted on 35 college students, who think it a bit tasteful or tasteless account for 66% of the total and those who think it a simple relish account for 60%, thus indicating that the dry ham still remains far away from the dining table.

• Culinary science and hospitality research
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• v.17 no.4
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• pp.316-325
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• 2011

The property of deep frying oil is one of die important factors in fried food quality. The purpose of this study is to identify die quality of deep frying oil in continuous usages for 4 days by two types of fryers: traditional and modified fryers. After frying polk cutlets, die flying oil was kept not only for several physical analyses such as color, viscosity, and water content but also for quality analyses of flying oil such as free fatty acid, double bond changes and oxidative rancidity formation. The fried oil by a traditional flyer was significantly increased in die physical values of color and viscosity than that by a modified fryer. In die acid value, the fried oil by a traditional fryer was significantly increased in free fatty acid than that by a modified fryer while die iodine value was significantly decreased in die fried oil by a traditional fryer when compared to control oil and fried oil by a modified fryer. In die peroxide value as an indicator of primary oxidation products, die fried oil by both fryers was significantly increased till die second day but decreased in die value after die third day because of unstable hydroperoxides' decomposition. In die p-anicidine value as an indicator of secondary oxidation products, die fried oil in a traditional fryer was significantly increased in die value than that in a modified fry.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.262-262
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• 2017

Brown rice contains a variety of nutritional and bio-functional components compared to milled rice. However, low consumer preference for steamed brown rice and short shelf life has been implicated as deterrents to the direct consumption of brown rice. This study was undertaken to determine the effect of degree of milling (DOM) on pasting and aging properties of brown rice cultivar. Short-grain (Japonica type) brown rice cv. Boseogchal (BSC), Baegjinju (BJJ), and Hiami (HIAM) were evaluated every month during 4 months storage. Rice cultivar were categorized into waxy (BSC), medium-waxy (BJJ), and non-waxy (HIAM) of which amylose contents were 6.81%, 10.06%, and 16.69~16.72%, respectively. Peak viscosity was the highest in BJJ followed by HIAM, and BSC, showing peak viscosity was lower at low temperature storage. At storage at room temperature from 60 to 120 days, the FFA content significantly increased in the rice samples with DOM1% followed by 3% and 5%, while not significant increase in DOM0% brown rice: at 120 days, the FFA ranged in 28.35~41.48, 111.99~130.06, 76.87~91.99, and 47.13~62.37 mg KOH/100g for DOM 0%, 1%, 3% and 5%, respectively. It indicated that the fat rancidity was the least in the order of DOM 0%, 5%, 3% and 1%. Storage at low temperature could reduce fat hydrolysis with lower FFA release, but rice grain with 1% MD also released more FFA compared to the other samples. It could be assumed that the most outer bran layer, approximately 1~3%, could provide a strong protection from fat rancidity. Pasting viscosity of rice samples also increased with increasing DOM rate. Results indicated that DOM was the most significant factor for lipid rancidity during storage, resulting in high FFA formation. It suggested that brown rice with DOM 0% and/or more than DOM 5% could provide the best shelf life.