• Korean journal of food and cookery science
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• v.32 no.6
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• pp.811-817
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• 2016

Purpose: People have long been interested about antioxidant nutrients such as vitamin A and E to stay in healthy states. This present study provides trustworthy nutritional information and evaluates vitamin A and E contents in emphasized food items. Methods: Vitamin A or vitamin E emphasized foods including beverage, cereal, snack, chocolate product, other cocoa products, and sugar products were analyzed. The contents of vitamin A, E in samples were examined by high performance liquid chromatography. Vitamin A and vitamin E contents were compared with the labeled value indicated on the nutrition label. Results: Vitamin A (n=18) value ranged from 90% to 248% and vitamin E (n=20) value ranged between 96-413% of labeled value. Analyzed samples ranged more than 80% of the labeled value, which complied with food labeling rules. Conclusion: Providing accurate information for nutrition label is essential to confirm nutrient contents in foods. It will help to decide the adequate level of nutrient intake. Therefore, the nutrition labeling system should be supervised continuously with regular monitoring analysis.

• Korean journal of food and cookery science
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• v.10 no.3
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• pp.225-231
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• 1994

This study was intended to observe the effect of cooked glutinous rice flour and soused shrimp on the fermentation of Kimchi samples were fermented for 11 days at 10$^{\circ}C$ after they were previously fermented for 6 hours at 20$^{\circ}C$. Changes of pH, total acidity, salt content, reducing sugar content, free amino acid content, total vitamin C content, and ascorbic acid content were measured. The results were as follows; 1. Soused shrimp and glutinous rice flour added in Kimchi acted as lactobacilli growth enhancer during fermentation. 2. Initial cincentrations of redng sugars in Kimch samples with no soused shrimp, 5% and 10% sosed shrimp were 7.5~8.3 mg/g, 3.0~4.7 mg/g and 0.5~0.6 mg/g respectively. Kinchi samples with glutinous rice flour showed higher reducing sugar contents than Kimchi samples without it. 3. Free amino acid contents in Kimchi samples gradually decreased during fermentation at 10$^{\circ}C$. According to their soused shrimp concentration, contents of free amino acid of Kimchi samples were significantly different. And Kimchi samples with glutinous rice flour showed lower free amino acid contents than Kimchi samples without it. 4. Total vitamin C contentrations of Kimchi samples were 24.5~28.0 mg% at the initial stage of fermentation and 15.0~19.2 mg% at the final stage of fermentation. During the fermentation of Kimchi, the higher soused shrimp concentration, the less total vitamin C contents were remained. 5. During the fermentation, ascorbic acid contents of Kimchi samples were not affected by soused shrimp and glutinous rice flour.

• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.14-20
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• 2018

Perfluorinated compounds (PFCs) have recently been recognized as global environmental pollutants. This study was performed to develop an analytical method for determination of levels of PFCs in food by LC-MS/MS. One hundred and nine food products were divided into two groups based on their fat and protein contents (high and low), following which samples containing high fat and protein contents were pooled and subjected to pretreatment consisting of enzymatic degradation and hexane extraction. The limit of detection of 17 PFCs in the samples were in the range of 0.013-0.145 ng/g. The degrees of precision of detection for group 1 (samples with low fat and protein contents) and group 2 (samples with high fat and protein contents) were 0.8-21.1 and 1.7-28.2%, respectively, with an accuracy of 78.8-109.8% for group 1 and 80-114.5% for group 2. This study indicated that pretreatment of high fat and protein foods with enzymatic degradation and hexane extraction would improve the detection of PFCs in food.

• Korean journal of food and cookery science
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• v.32 no.1
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• pp.9-15
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• 2016

The changes of resistant starch (RS) contents of cooked rice with soybean and coconut oils under different storage conditions were investigated and RS contents were compared between the rice and cooker types. The japonica (Hopyeong) and the indica (Thailand) type rice were cooked (washed rice: water = 100: 130) using an electric cooker and a saucepan. The coconut oil and soybean oil (3%, based on rice, w/w) were added into cooking water before heating. The RS contents of freeze-dried cooked rice powders (newly-cooked rice, stored for 12 h in the refrigerator, microwave heating after storage for 12 h in the refrigerator) were measured by the AOAC method. The RS contents of cooked rice using a saucepan were higher than those using an electric cooker. The indica type cooked rice had a higher RS content than the japonica type cooked rice, regardless of storage conditions. However, addition of oil before cooking rice resulted in increased RS content on storage in the refrigerator. The highest RS content of the cooked indica type rice with soybean oil ($5.89{\pm}0.22%$) that was stored for 12 h in the refrigerator was analyzed. The results suggested that the cooked rice formed retrograded (RS3) and amylose-lipid complex (RS5) type RS; furthermore, the RS content is affected by storage conditions, rice, cooker and oil types.

• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.519-524
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• 2005

This study was carried out to survey the contents of mineral and heavy metal of the commercial salt and salted-fermented shrimp. Mineral and heavy metal contents of Korean products and imported salts, and their effects on shrimps were analyzed through ICP-AES/MS. K and Mg contents of Korean salts and salted-fermented shrimp were relatively higher than those imported ones, However, no significant differences were found for mineral of commercial salted-fermented shrimps between Korean products and imported ones. Heavy metal contents of commercial salts lower than the maximum permissible limit set by KFDA. As, HB, and Ni were not detected in both commercial and lab-made salted-fermented shrimps. Cd were detected ranges of ND-0.5 ppm (average 0.1ppm) for commercial salted-fermented shrimps. Pb were detected ranges of ND-0.8ppm(average 0.28ppm) for lab-made salted-fermented shrimps.

• Korean journal of food and cookery science
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• v.27 no.6
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• pp.745-754
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• 2011

To improve the textural properties of gluten free rice flour based products, the physicochemical and pasting properties of extruded non-waxy rice flours using extruder were investigated. The high yielding Tongil type rice variety, Hanarum was used. Hanarum rice flour was prepared by dry milling from soaked and dried rice grain. The operation conditions of twin screw extruder were 250 rpm of screw speed, $160^{\circ}C$ of barrel temperature, and 24, 27, and 30% of moisture content. Hanarum extruded rice flour (HERF) were lower in crude lipid and ash contents, but higher in crude protein than Hanarum rice flour (HRF). The color values of HERF showed significantly different (p<0.05) with different moisture contents. Water binding capacities, apparent amylose contents, and damaged starch of HERF were higher than those of HRF. Moisture contents affected water binding capacities of HERF. Solubility increased with increasing heating temperature and solubilities of HERF differed significantly (p<0.05). X-ray crystallinity was changed after extrusion cooking and that of HERF showed sharp peaks at $2{\theta}=18-20^{\circ}$. The pasting viscosities of HERF kept lower values (~ 10 RVU) constantly.

• Korean journal of food and cookery science
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• v.14 no.5
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• pp.509-512
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• 1998

Changes in the contents of stachyose and raffinose were determined during soybean fermentation. ${\alpha}$-Galactosidase activities were also monitored in soybean and its fermented products. The stachyose contents were 31.8239 mg/g of soybean, 4.2217 mg/g of Meju, and 2.1184 mg/g of Doenjang. The raffinose contents were 2.6914 mg/g of soybean, 1.7413 mg/g of Meju, and negligible of Doenjang. ${\alpha}$-Galactosidase activities was distinct in soybean and Meju. They were 14.5954 units/mg protein of soybean, 13.1489 units/mg protein of Meju, and 1.9157 units/mg protein of Doenjang. The results suggested that the decrease of stachyose and raffinose contents in fermented soy products were due to the ${\alpha}$-galactosidase activity.

• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.177-179
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• 1992

The theanine contents of commercial green teas manufactured by the different harves times(1st tea, 2nd tea and 3rd tea) and processes(steamed and parched teas) were determined by amino acid analyzer. There were remarkable differences in the theanine contents among teas of the different harvest times. The theanine content in 1st steamed green tea was 2235 mg% and one in 1st parched green tea was 2106 mg%. The theanine contents in 2nd, 3rd tea were gradually decreased. There were slight differences in the theanine contents among teas of the different process.

• Korean journal of food and cookery science
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• v.2 no.2
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• pp.68-75
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• 1986

The changes of dietary fiber and texture of radish Kimchi fermented at $17{\sim}20^{\circ}C$ were investigated. During the fermentation period, hardness and brittleness of radish Kimchi were decreased. The changes were more marked in the brittleness. But the contents of cellulose and hemicellulose were not changed considerably. The contents of AIS was decreased with fermentation. During the fermentation, hot soluble pectin was increased and protopection was decreased but the amount of changes was small. The texture of radish Kimchi was affected by contents of pectic subsrances, especially protopectin. The coefficient of correlation between hardness and protopectin contents was 0.85.(=r)

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.702-707
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• 2011

The purpose of this study was to analyze the bioactive compounds of soybean snacks and to carry out a sensory evaluation of those variations which had various seasoning mixing ratio. Five soybean snacks were developed for these experiments. Proximate composition, the contents of total phenol compounds and isoflavone, and sensory characteristics of the soybean snacks were measured. There were significant differences in amounts of isoflavones and total phenolic compounds of soybean snacks($p$ <0.05). The seasoned soybean snacks had a higher level of daidzein and genistein contents than did control group. The total phenol compound contents of the control group was 210.3 mg gallic acid equivalents/100 g, whereas those for individual soybean snacks(A~E) were 152.3, 160.2, 162.4, 158.4 and 164.6 mg gallic acid equivalents/100 g, respectively. In sensory evaluation, there were significant differences($p$ <0.05) in taste, texture, and overall acceptability of the soybean snacks.