• Food Science of Animal Resources
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• v.40 no.5
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• pp.785-794
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• 2020

Food Codex regulations have set freshness limits for oils used to fry food, such as potato and fish products, and fried food itself; however, no such freshness limits have been set for meat products, such as sweet and sour pork. The freshness standard suggest that acid values (AVs) and peroxide values (POVs) for frying oil should be less than 2.5 and 50, respectively, whereas AVs and POVs for common fried food should be less than 5.0 and 60, respectively. Therefore, in this study, we investigate the effect of the number of frying cycles on oxidation-promoted changes in the oils used to fry sweet and sour pork and fried food itself during repeated frying over 10 d by determining their AVs and POVs, which were found to be highly correlated. Soybean, canola, palm, and pork lard oils could be reused approximately 37, 32, 58, and 87 times, respectively, to fry sweet and sour pork based on oil freshness, and 78, 78, 81, and 286 times, respectively, based on the freshness of fried food. Our data may help establish food-quality regulations for oils used to fry animal-based foods.

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.264-271
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• 1999

This study was conducted to know the storage stability of Yackwa, a traditional Korean fried cookie, prepared by two different cooking methods; deep fat frying at 160$^{\circ}C$ for 8 min (DFF), and preheating Yackwa dough and then deep fat frying at 180$^{\circ}C$ for 2 min (MW/DFF). Soybean oil (SBO), hydrogenated soybean oil (HSBO) or hydrogenated palm oil (HPO) were used for frying Yackwa. Compared to Yackwa prepared by DFF, all MW/DFF Yackwa samples had low fat content and high moisture content. MW/DFF saved frying time 6 min compared with DFF. Non-hydrogenated soybean oil for frying fats was replaced with hydrogenated types of soybean oil and palm oil to improve the storage stability of Yackwa. To investigate the oxidation stability of Yackwa during the accelerated storage for 15 days at 60$^{\circ}C$, acid value, anisidine value, peroxide value and oxidation value of Yackwas were measured. Acid values of Yackwa made by MW/DFF were higher than those made by DFF through the whole storage periods, regardless of frying fats. Peroxide and anisidine values of Yackwa coated with syrup were much lower than those without syrup. MW/DFF cooking method, using hydrogenated soybean oil or hydrogenated palm oil for frying, showed lowering effects on peroxide value as well as anisidine value, resulting in improved oxidation stability of Yackwa during the storage. In sensory evaluation, the acceptability of MW/DFF Yackwa was higher than those of the commerical products. Yackwa prepared by MW/DFF cooking method using hydrogenated palm oil, showed the highest acceptability in color, taste and texture among the samples.

• Korean Chemical Engineering Research
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• v.49 no.5
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• pp.617-622
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• 2011

A simple method has been successfully applied to extract squalene and its byproducts alkoxyglycerol from deep-sea shark liver oil. GC-MS was used to determine the extraction amount of the squalene and alkoxyglycerol, and the content of them in rough product and refined product were compared. The physical property of squalene was identified by measuring the pH value, peroxide value and iodine value. Under optimum extraction conditions, the amount of squalene and alkoxyglycerol increased 35.0% and 21.9%, respectively, while the amount of fatty acid decreased from 61% to 4%, especially, the amount of palmitic acid and oleic acid remarkably decreased. Large amount of peroxide and acid were removed from shark liver oil after refining process. Because squalene contains lots of double bond, so the value of iodine is much higher than squalane.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.2
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• pp.234-241
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• 2008

The purpose of this study was to evaluate antioxidant effects of oriental herbs in the pork meat Wanja(0.5${\times}$5 cm, 20 g) baked at 180$^{\circ}C$ for 5 min and reheated 30 see in microwave oven after storage at 4$^{\circ}C$ for 4 days. The moderate amount of freeze dried powder of oriental herbs included in Wanja were 1.0% in CN(Cinnamomum lureitri Nees), 0.5% in AS(Acanthopanax sessiliflorus Seed), and in AN(Angelica gigas Nakai), respectively. In sensory evaluation, the Wanja added with AS was the most preferred significantly. The Wanja without oriental herbs was the least preferred because of its the highest level in off-flavor. During storage at 4$^{\circ}C$ in the refrigerator for 10 days, the Wanja without oriental herbs was increased rapidly in acid value after 6 days, but the Wanja made with 1.0% CN powder was increased after 8 days, and with 0.5% AS and 0.5% AN were after 10 days. The Peroxide value of Wanja without oriental herbs was increased to unedible level after 8 days. But those of Wanjas made with CN, with AS, and with AN were increased to low level enough to eat till 10 days. The result in peroxide value between of Wanjas with and without oriental herbs was the same tendency in TBA value.

• Korean Journal of Veterinary Research
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• v.41 no.3
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• pp.387-393
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• 2001

The chemical composition of fish feeds(mackerel, gizzard shad, shrimp and formula feed) were analyzed and compared with those of untreated and irradiated (5 kGy) feeds, and the effects of gamma irradiation (5 kGy) and butylated hydroxyanisole (BHA, 200ppm) on feeds spoilage were investigated by determination of thiobarbituric acid (TBA) value and peroxide value for 14 days at $20^{\circ}C$, $4^{\circ}C$ or $-20^{\circ}C$. Crude protein, crude lipid, crude fiber, crude ash and nitrogen free extract were not significantly changed by gamma irradiation with the dose of 5 kGy. Immediately gamma irradiation increased the initiative oxidation of feeds as expected. But BHA was found to be greatly effective in minimizing the radiation-induced peroxidation (p<0.05). The TBA value and peroxide value increased with the elapse of the storage period. The level of lipid oxidation was increased depending on the rise in storage temperature. But the additions of BHA inhibited the lipid oxidation (p<0.05).

• Korean Journal of Poultry Science
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• v.34 no.2
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• pp.99-104
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• 2007

Studies were conducted to evaluate spent bleaching clay as a feed resource. Raw spent bleaching clay from the soybean refining process in a rotary reactor is rich in crude fat (26.0%) and crude ash (68.3%) but low in moisture (5.2%) and crude protein (0.5%). The peroxide value of spent bleaching clay was significantly higher than soybean oil (P<0.05). Also the acid value of spent bleaching clay and soybean oil were 9.72 and 0.001, respectively, it was significantly different(P<0.01). It is possible that the acidification of spent bleaching clay was prevented by artificial method. On the feeding experiment, 2.0 to 4.0% of dietary spent bleaching clay were improve body weight gain, feed intake and feed/ gain. Results indicate that spent bleaching clay may be used at 2.0 to 4.0% for broiler diets without deleterious effects on performance.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.180-185
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• 1985

The alkali refined rice bran oil (ARBO) and the esterified rice bran oil (ERBO) with glycerol were compared for their thermal stabilities at $150^{\circ}C$ and $180^{\circ}C$, respectively. The acid value gradually increased in ARBO during heating period but increased slowly in ERBO-2 and declined gradually in ERBO-1. The peroxide value was somewhat fluctuated during heating period, and the maximum peroxide value in all samples was 13.3 meq/kg. TBA value was sharply increased for the first 10 hr. heating and slowed down thereafter for all samples but ERBO were intensely colored after the heat treatment. The TG ratio of the oils after 90 hr. heating was not different at $150^{\circ}C$ but ERBO was 2-7% higher ratio of TG than ARBO at $180^{\circ}C$. The oxidative stability of ARBO was twice higher than ERBO according to the result of active oxygen test.

• Journal of the Korean Society of Food Culture
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• v.18 no.1
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• pp.1-8
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• 2003

Recently, the concern about safety and functional substances of foods are increased therefore antioxidant substances and plants which had pharmacological effect have been studied actively. It has been known that the mulberry leaf is effective in curing many diseases. Nowaday, the pharmachological effects of mulberry leaves on diabetes mellitus and their usage for many aspects were confirmed. Mulberry leaves are known for effective in prevention of diabetes mellitus, because of specific amino acids and fibers. In this study, methanol, hexane, chlorform, ethyl acetate, and butanol extracts obtained from mulberry leaves were added to soybean oil and they were stored for 30 days at $60{\pm}2^{\circ}C$ and peroxide value(POV) and conjugated diene value(CDV) were measured periodically. Results of this study were obtained as follows; 1. The POV of soybean oil after the addition of each mulberry leaves powder(MLP) extracts generally enhanced as the storage time was prolonged, so the POV of all samples was reached higher than 100meq./kg.oil after 10 days storage without the addition of butanol, methanol, ethylacetate, hexane extracts at 0.1% level. Especially, the POV of soybean oils including butanol extract was 87.35meq/kg.oil after 10 days storage and antioxidant activity of butanol extract was shown to be superior to that of BHT. The pattern of the changes of the CDV of soybean oil after the addition of MLP extracts at 0.02%, 0.05% and 0.1%, respectively, were almost constant during 10 days of storage and then rapidly increased during the rest of experimental periods. During 10 days of storage in case of 0.1% adding level, the antioxidant activities of the butanol extract was superior to that of the each MLP extracts.

• Korean journal of food and cookery science
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• v.19 no.1
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• pp.60-64
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• 2003

Yukwa is a popular Korean traditional fried rice snack. The high fat content and porous structure of Yukwa cause it to become rancid rapidly. For extending the shelf-life of Yukwa, the Bandegi was fried with palm oil and soybean oil. The stability of Yukwa in lipid oxidation was determined by acid value(AV), peroxide value(POV), composition of fatty acid and sensory evaluation during 8 weeks of storage at 20$^{\circ}C$ and 50$^{\circ}C$ As the storage time increased, the AVs of soybean oil and palm oil during storage at 50$^{\circ}C$ were increased up to 42.64 and 2.09 mg/g, respectively. The POV of soybean oil during storage at 50$^{\circ}C$ was increased up to 4 weeks and then decreased. And as the storage time increased, the contents of stearic and oleic acid were increased, while linoleic and linolenic acid were decreased.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.6
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• pp.950-957
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• 2009

Mustard Leaf Kimchi (MLK) is a traditional fermented Korean vegetable food. This study was conducted to investigate the effects of part vacuum treatment on MLK packed in a glass bottle during fermentation. There have been a few previous studies that examined the chemical and microbial changes during MLK fermentation. However, the major object of this study was to investigate the antioxidative activities of vacuum treated MLK. In this study, the antioxidative activity of vacuum treated mustard leaf Kimchi (VM) and control mustard leaf Kimchi (CM) were examined. VM and CM were fermented at $5^{\circ}C$ for 8 weeks. A model system was designed to evaluate the antioxidative activity of crude chlorophylls and carotenoids (CCC) extracts from Mustard leaf Kimchi. The oxidative reaction of the linoleic acid mixture system at $30^{\circ}C$ in the dark was quantified determining the peroxide value and conjugated dienoic acid content. The effect of the CCC extracts on lipid peroxidation in a rat liver homogenate was examined. Formation of lipid peroxides was estimated by the TBA value, and the CCC extracts were found to inhibit the TBA value. Chlorophyll a and b, and carotenoids, Which are the major components in the CCC extracts of Kimchi were isolated on a DEAE-sepharose CL-6B and Sepharose CL-6B column and TLC. The effects of chlorophyll a and b, caroteins on linoleic acid autoxidation were measured by determining the peroxide value. In addition, their effects on free radical scavenging were investigated by DPPH. In this assay, chlorophyll a showed the greatest antioxidative activity followed by chlorophyll b, and carotenoids. MLK contains a sufficient content of chlorophyll a and b, and carotenoid which have strong antioxidative activities.