• Korean Journal of Food Science and Technology
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• 제3권1호
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• pp.19-24
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• 1971

The Korean rice, Nonglim # 6 was milled into brown rice and 92% polished one and packed with the kraft paper bags. The sample, bags were irradiated with the respective doses of 30, 50, 600 and 800 Krad and then were stored at $10^{\circ}C$ and 75% RH. Changes of fat acidity, amylase activity, viscosity of thus irradiated rice were examined during storage. The results were as follows. 1) Fat acidity increased slightly in the range of $30{\sim}50$ Krad but remarkably in the range of $600{\sim}800$ Krad. However, the rate of increase was low in comparison with the storage under the room temperature. 2) The amylase activity of both the low dose lot and the control decreased in the same rate during the storage. However the high dose lot had more remarkable decrease of the amylase activity from the beginning. 3) The viscosity by Brabender amylogram showed the slightly decreasing tendency in both the low $30{\sim}50$ Krad lot and the control lot of the polished rice powder during storage. On the other hand, the high dose lot of 600 or 800 Krad marked the similar decreasing rate but by far the lower values of the viscosity. 4) The results of the organoleptic test presented no differences between the low dose lot and the control lot, but the high dose lot and the control lot differed significantly only in the color.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제15권1호
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• pp.99-106
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• 1982

Vacuum-packed and seasoned-dried products of filefish, Navodon modestus, caught in large quantities in the coasts of Japan and Korea, were prepared tentatively and stored at $35^{\circ}C$ for $3\sim4$ months to test their keeping quality. Headed, eviscerated, ana skinned filefish were purchased from Tokyo central wholesale market and filleted. The fillets were seasoned with the seasoning powder prepared from sugar, sorbitol, salt, glutamate, 5'-ribonucleotide, and either beef flavor (Flava-Beef, Kyowa Hakko Kogyo Co. Ltd.), red pepper, or smoke flavor (Smok-EZ, Alpha Foods Co. Ltd.). After seasoning, the fillets were dried at $39\sim41^{\circ}C$ for several hours, vacuum-packed in the bag of plastic film, and cooked in water of $80^{\circ}C$ for 40 min. Two kinds of products different in moisture level were prepared : one containing moisture of $26\sim29\%$ and the other $40\sim46\%$. The moisture level, water activity, color value (L,a, and b values), texture, and viable counts of bacteria of these products were determined during storage at $35^{\circ}C$. From the results obtained, it became clear that the products could be preserved in good condition for $3\sim4$ months at $35^{\circ}C$, though they slightly decreased in the softness with decrease of moisture content and developed a pale brown during storage. Judging from organoleptic evaluation on the flavor, the products containing beef flavor as a seasoning was most desirable.

• Applied Biological Chemistry
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• 제40권4호
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• pp.313-317
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• 1997

To assess the physiochemical characteristics of greenhouse Satsuma mandarin (Citrus unshiu Marc. var, miyakawa) produced in Cheju, were analyzed chemical compositions for fruits, external and internal factors influencing the edible quality. Changes in organoleptic value according to brix and acid content were also evaluated. The ratios of sucrose : glucose : fructose in citrus juice were 2 : 2 : 1.5. Citric acid as the main acid in the juice represented about 70% of total organic acid. Most of the amino acids were found to be nonessential amino acids. Deep yellow color of the citrus peel showed a significant relationship(r=0.563) with brix/acid ratio of the citrus juice, indicating the ripeness of the fruit. Since the acid content showed highly negative statistical relationship(r= -0.882) with the pH value of the juice, the pH value appears to be a simple indicator for the sourness of the fruit in the field test. The fruits were divided into 9 groups based on the brix/acid contents for sensory evaluation. The palatability patterns of each group changed depending on the acid content. The optimal ranges of brix/acid content for acceptable taste were 11 and $0.5{\sim}1.0$, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제8권1호
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• pp.37-45
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• 1975

The present study was ,conducted to evaluate the effects of condensed phosphates on the refeezing damage of Alaska pollack muscle. The fillets were dipped in such solution as 5 and $10\%$ sodium polyphosphate, 1 and $5\%$ mixture of sodium polyphosphate and sodium pyrophosphate (1:1, w/w) for 1 and 5 minutes, respectively, before refreezing. And fillets were frozen at $27^{\circ}C\~28^{\circ}C$ and stored for 15 days at $-18^{\circ}\~-20^{\circ}$. The degree of denaturation was estimated by determining amounts of drip relased, content of total solids, nitrogen, and DNA in the drip an cooking-weight-loss. Phosphorus absorbed in the muscle was also determined. Phosphorus absorbed in the fillets treated with loft solution of sodium polyphosphate for 5 minutes amounted to 101 mg/100g muscle as $P_2O_5$. The absorption was dependent on tile concentration of treating solution rather than on the dipping time. The increase of phosphorus absorption seemed to affect to reduction of drip. Among the treating conditions, $10\%$, 5 minutes and $10\%$ 1 minute with sodium polyphosphate appeared most effective ones on drip reduction. The effect of $5\%$, minutes with the mixture of sodium polyphosphate and sodium pyrophosphate did not show so benefitable effect in refrozen fillets. As a tendency total solids, nitrogen, and DNA in tile drip varied proportionally to the amount of drip released. And the content of DNA was lower than the amount. Treatment, at higher the concentration and longer the dipping time, resulted in the lower cooking-weight-loss and the better quality on organoleptic test of thawed fillets.

• Korean Journal of Food Science and Technology
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• 제20권3호
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• pp.293-302
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• 1988

This study was performed to identify detailed informations on the nonvolatile flavor of Chinese quince fruits, Chaenomeles sinensis koehne. About 72% of the free amino acids were shown to be valine, asparagine, ${\gamma}-aminobutyric\;acid$, aspartic acid and serine. Arginine, tyrosine, methionine and tryptophan were not present. Glutamic acid and glutamine as a amino acid for peptides were the major components, whereas cysteic acid, methionine sulfone and tryptophan were not detected. The nucleotides attained were composed of cytosine, uridine-5'-monophosphate and cytidine-5'-monophosphate, and these were proved to be a very small quantity. Guanosine-5'-monophosphate, inosine-5'-monophosphate and adenosine-5'-monophosphate were not present. The major sugars were shown to be glucose, sorbose, sucrose and fructose. Fructose was the most abundant one among them. A total of 11 organic acids were identified by capillary gas chromatography and capillary gas chromatography-mass spectrometry. The major components identified were tartaric acid and α-ketoglutaric acid. The total content of vitamin C determined was 386.6mg%, and those of ascorbic, dehydroascorbic, and 2, 3-diketo-L-gulonic acid were 28.8mg%, 154.5mg% and 197.3mg%, respectively. Calcium and phosphorus were the major components, while heavy metals such as cadmium, copper and lead were determined to be a small amount. In the result of organoleptic test on the natural and synthetic extract of Chinese quince fruits, the principal taste components consisted of free amino acids, sugars, organic acids, vitamin C and minerals. Five groups mentioned would have a favorable influence upon the taste of fresh Chinese quince fruits.

• Journal of Food Hygiene and Safety
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• 제5권1호
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• pp.13-19
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• 1990

The microbial populations of exportable ginseng leaf tea were $3.6{\times}10^{5}/g$ in mesophilic aerobic bacteria, $2.1{\times}10^{3}/g$ in mesophilic aerobic spores, $1.6{\times}10^{4}/g$ in yeast, $1.9{\times}10^{4}/g$ in molds and $1.2{\times}10^{4}/g$ in coliforms, respectively, which are higher levels than the legaJIy permissible loads of microorganisms for ginseng powders in Korea. In a comparative study of the decontaminating effects on microorganisms, ethylene oxide fumigation and 5 kGy irradiation could decrease microorganisms below the detectable level. And there is no growth of microorgllnisms after three months of storage at $30{\pm}1^{circ}C$. The decimal reduction doses (Dw value) for microorganisms contaminated were 0.70 kGy in coliforms, 0.75 kGy in total bacteria, 0.85 kGy in molds. and 0.95 kGy in yeast, respectively. In the organoleptic test for ginseng leaf tea, the irradiated samples showed no significant difference from the control group in overall flavor, taste, color and acceptability. However the extracts of ethylene oxide fumigated sample were significantly different in color and taste from other groups even after three months storage.

• Korean Journal of Food Science and Technology
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• 제21권4호
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• pp.468-479
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• 1989

The oxidative stability of the ramyon prepared with rapeseed oil fortified with antioxidants or blended with palm oil was studied to explore the possibility of substituting it for Imported frying fats and oils. Natural tocopherols, butylated hydroxyanisole(BHA), tertiarybutyl hydroquinone(TBHQ), and ascorbyl palmitate with citric acid were used at a level of 0.02 percent. Blended oils were prepared by adding a palm oil to the rapeseed oil at ratios of 7:3, 5:5, and 3:7(w/w), respectively. Ramyon samples were stored at $35.0{\pm}0.5^{\circ}C$. for 90 days. The values of parameters, such as peroxide value, unsaturation ratio, and dielectric constant, of the extracted oils were regularly determined. An organoleptic test for the flavor of the samples was also performed. The oxidative stability of the samples was estimated on the basis of the changes of the parameter values. The effectiveness of the antioxidants was in the order of TBHQ ${\gg}$ ascorbyl palmitate with citric acid>BHA>natural tocopherols. The oxidative stability of the ramyon prepared with the rapeseed oil containing 0.02 percent TBHQ was almost as good as that of the ramyon prepared with the palm oil. The stability of the ramyon prepared with the blended oil containing 70 percent palm oil was also as good as that of the ramyon prepared with the palm oil.

• Korean Journal of Food Science and Technology
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• 제4권1호
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• pp.18-23
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• 1972

Fried instant noodles, manufactured on laboratory scale, preserved in sunlight, room temperature, removed package, at $30{\pm}2^{\circ}C$ and corrugated fiber board box to investigate the oxidative stability of fried products under a few factors of storage for 150 days. And obtained results were as follow. 1) Peroxide value P.O.V. and Acid value A.V. of fried instant noodles were increased slightly during the storage in orange color polycello package in the corrugated fiber board box in the dark room as shown in Fig. 1 and 2. They had not rancid odor and showed P.O.V. 18.8 after 150 days. 2) Preserving in room temperature removed package or with polycello package exposed to sunlight, P.O.V. and A.V. increased rapidly up to 100, 5 and they had rancid odor within 30 days. 3) Peroxide value showed increasing tendency on the storage at $30{\pm}2^{\circ}C$ and scattered light and rancid odor appeared from 90 to 120 days. 4) As peroxide value and refractive index increased, iodine value were decreased as Fig. 3. 5) In these test, P.O.V. is correlated with the organoleptic evaluation of rancidity however, they were not coincided exactly.

• Korean Journal of Food Science and Technology
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• 제29권4호
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• pp.635-640
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• 1997

The oxidative stability of the potato chip prepared with canola oil fortified with antioxidnats was studied to explore the possibility of substituting it for imported frying fats and oils. BHT, BHA, TBHQ and silicone were added to the oil at a level of 0.02% and 10 ppm, respectively. Potato chip samples were prepared in a commercial scale and stored at $25.0{\pm}0.5^{\circ}C$ for 5 months. The oxidative stability of the extracted oils from potato chips during storage was estimated on the basis of some their physico-chemical changes, such as acid values, peroxide values, iodine values, ansidine values, fatty acid composition of the oils. An organoleptic test for the flavor of the samples was also performed. The oxidative stability of the samlpes was estimated on the basis of the changes of the parameter values. The effectiveness of the antioxidants was in the order of canola oil+TBHQ (0.02%)+silicone (10 ppm) > canola oil+TBHQ (0.02%) > canola oil+BHA (0.02%)+silicone (10 ppm) > canola oil+BHT (0.02%)+silicone (10 ppm) > canola oil+BHA (0.02%) > canola oil+BHT (0.02%) > canola oil. The antioxidant effect of canola oil+TBHQ (0.02%)+silicone (10 ppm) was more salient than any other antioxidant used in the potato chip.

• Journal of the Korean Society of Food Science and Nutrition
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• 제13권2호
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• pp.131-135
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• 1984

For the convenience of transportation and improvement of the utility of raw chinese cabbage during harvest season, the condition of pretreatment for the raw chinese cabbage with pickle has been examined by preserving for one to ten days. The changes in the content of riboflavin and ascorbic acid in kimchi (pickled-seasoned chinese cabbage), which was manufactured by using the pickled cabbage as a main raw material, along with ginger, garlic, red pepper powder, rad-dish and fermented shrimp as seasonings, during ripening were investigated with specially referred to palatability. The yield of the pickled cabbage compared to the raw cabbage after treating with pickle was 62 to 65% in volume and 15 to 42% in weight. After 10 days of pickling of the chinese cabbage, one-third of total ascorbic acid was diminished but no change in riboflavin content was observed. During ripening of kimchi, riboflavin content in kimchi processed with the pickled cabbage has not been changed compared to the content in convention- ally made kimchi, however, slight decrease in ascorbic acid content in the kimchi processed with the pickled cabbage was as certained. The result of organoleptic test showed that the kimchi processed with the pickled cabbage became inferior to the conventionally made kimchi with the days of ripening.