• Korean Journal of Food Science and Technology
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• v.12 no.4
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• pp.313-323
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• 1980

The objective of this experiment was to improve the quality and shortening the aging time of Kochujang by adding mixed starter cultures of yeast strains. Kochujangs were mashed during the summer season with mixed starter cultures of Saccharomyces rouxii, Torulopsis versatilis and Torulopsis etchellsii. Enzyme activities and chemical composition of the Kochujang were determined during the period of aging and their organoleptic values were tested. The maximum activities of liquefying amylase and saccharogenic amylase in the Kochujang were obtained during 20 to 60 days and 20 to 30 days after mashing respectively. The acidic protease activity was reached maximum during 20 to 40 days. All enzyme activities were decreased markedly during the final stage of aging period. Among mixed starter cultures tested, mixed culture of T. versatilis and T. etchellsii shows the highest liquefying and saccharogenic amylase activities. Ethyl alcohol contents in 10 days after mashing were highest in the Kochujang with S. rouxii and T. versatilis, followed in order of S. rouxii and T. etchellsii mixture, T. versatilis and T. etchellsii mixture and control without addition of yeast. But the contents in all sample became similar after 20 days with the level of 2.3 to 2.8% and then decreased gradually. The level of reducing sugar contents was markedly increased during the first 10 days, especially in the batches of T. versatilis and T. etchellsii mixture and control. However, the concentration became similar in all samples after 40 days. The contents of amino nitrogen were increased markedly during the first 10 days then slowly up to 90 days. The rate was high in the Kochujang with T. versatilis and T. etchellsii when compared with others. The organoleptic values of all Kochujang made with addition of yeast starter cultures were superior to control, especially in flavor, taste and color. The Kochujang with T. versatilis and T. etchellsii marked the highest value. The data obtained from this experiment suggests that the quality of Kochujang could be improved by using starter culture of suitable yeast strains according to product characteristics and aging time.

• Applied Biological Chemistry
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• v.47 no.1
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• pp.96-106
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• 2004

Response surface methodology (RSM) was applied in roasting processes of perilla leaves to develop a high quality perilla leaf tea. The Hunter color parameters and electron donating ability were monitored to optimize organoleptic properties of perilla leaf tea. The roasting processes were based on the central composite design with primary variables-roasting temperature $(140{\sim}220^{\circ}C)$, time $(5{\sim}25)$, and reaction variables-sensory test, electron donating ability. From the variables, the roasting condition was optimized using statistical analysis system (SAS) program as developing the functional tea using perilla leaf. Hunter color L and b values of the powdered samples increased with the roasting processes, but Hunter color a value decreased. Electron donating ability was influenced by roasting temperature (p<0.01) and time (p<0.01), and optimum condition selected was at $220^{\circ}C$ for 15 min with coefficient of determinations $(R^2)$ above 0.98. After preference test of perilla leaf tea using parameter of taste, color, and flavor, we can estimate that the optimal roasting condition of preilla leaf for function tea manufacturing are $210{\sim}220^{\circ}C$ for $10{\sim}20$ min by response surface methodology (RSM). Tyrosinase, xanthine oxidase and electron donating ability were 10.14, 14.37 and 59.19% of perilla leaf tea.

• Journal of Dairy Science and Biotechnology
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• v.35 no.1
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• pp.9-15
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• 2017

Cichorium intybus L. (chicory) roots and leaves are widely used in herbal preparations, which have beneficial effects on the stimulation of digestion and metabolism of food ingredients, gastric juice excretion, diuretic action, and bile excretion. Notably, chicory root is well known as a source of polyphenols, compounds with recognized value in health improvement. In this study, we examined the physicochemical characteristics (TA, pH, and sensory evaluation) of bioactive yoghurt containing different concentrations of chicory. With increasing incubation time (5 h), the TA of the yoghurt increased whereas the pH decreased, regardless of the amount of chicory. As the amount of chicory increased, the scores for color, flavor, taste, and overall acceptability generally decreased. Among the tested groups, yoghurt with the addition of 1% chicory attained the highest scores. Further studies on the production of bioactive yogurt with optimum chicory concentration are needed.

• Korean journal of food and cookery science
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• v.26 no.5
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• pp.530-536
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• 2010

This study was the tenderizing activity of fig and kiwifruit using meat cooking. Furthermore, the effects of various seasonings and flavor spices were investigated. The proteolytic activity of kiwifruit was 36,513 uM/g fruit, whereas that of fig was 24,131 uM/g fruit. The best amount of fruit for meat cooking was 3~5% for kiwifruit and 5% for fig among three different dilutions, 3%, 5% & 10%. The effect of fruit ratio showed that treatment with 'kiwifruit only' produced the best organoleptic results, and there was no significant difference between the kiwifruit and fig ratios, 3:0, 2:1, 1:1. The best marinating time for meat tenderizing by fig and kiwifruit was 6hr at $4^{\circ}C$. The best marinating temperature for meat tenderizing by fig and kiwifruit was $25^{\circ}C$ rather than $4^{\circ}C$. Fruit sauce containing basic seasonings such as soy sauce, sugar, oligosaccharides, and sesame oil had a pH of 4.64 for fig and 4.23 for kiwifruit. The addition of soy sauce, oligosaccharides, and rice wine decreased the proteolytic activity of the fruits. Fruit sauce containing basic seasonings, garlic, ginger, onion and scallion had a pH of 4.71 for fig and 4.43 for kiwifruit. Finely chopped garlic, finely chopped scallion, and pureed onion, finely chopped ginger, and pear juice, all increased the proteolytic activity of the fruits. There the fruit sauce containing seasonings and flavory spices for meat cooking improved the tenderness and preference in terms of sensory evaluation without undesirable taste or increased fruits.

• Korean Journal of Food Science and Technology
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• v.6 no.2
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• pp.65-69
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• 1974

Noodles were made from composite flours based on barley or sweet potato/wheat flour and their quality was assessed to obtain the following results. 1) In noodle sheet and dried noodle formation, barley flour could substitute 100% and sweet potato flour, 70% of wheat flour and their textural characteristics were improved by addition of glyceryl monostearate and sodium polycrylate. 2) Textural parameters such as hardness, cohesiveness and gumminess of noodle sheet and dried noodle were decreased by admixture of barley of sweet potato flour whereas they were increased by use of the additives. Noodle sheet required hardness over 6.2 and gumminess over 430 while dried noodle needed hardness over 6.8. 3) In cooked noodle, replacement of wheat flour and use of additives tended to lower the textural parameters. With respect to the cooking quality, barley flour could substitute 60% and sweet potato flour, 40% of wheat flour. 4) In organoleptic evaluation of cooked noodle with respect to its color, taste and texture, 20% replaced composite flour was not different significantly at 5% level from wheat flour and the quality defect was mainly due to discoloration of the product.

• Applied Biological Chemistry
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• v.40 no.4
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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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• v.30 no.1
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• pp.8-15
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• 1997

For an effective use of fish by-products from the skipjack tuna (Katsuwonus pelamis) canning manufactures, the changes of chemical properties of skipjark tuna viscera silage by the processing method during storage were investigated. The acid treated skipjack tuna viscera silage (ASS) were higher in the contents of moisture, lipid, protein and mineral but lower in the contents of carbohydrate and polyunsaturated fatty acids than those of fermented skipjack tuna viscera silage (FSS) by L. bulgaricus, KCTC 3188 and L. plantarum, KCTC 1048. Especially, the contents of total n-3 fatty acids in FSS increased remarkably during storage. The dominant amino acids in ASS and FSS were glutamic acid (Glu), aspartic acid (Asp), leucine (Leu), glycine (Gly) and alanine (Ala). And the contents of tryptophan (Trp) decreased by $30\%$ in ASS and $5\%$ in FSS in comparision with that of raw skipjack tuna viscera after 42 days of storage. The concentration of vitamin $B_1\;and\;B_2$ in FSS increased gradually during storage but the concentration of vitamin $B_2$ in ASS decreased. In the organoleptic evaluation, ASS gave a grayish brown color and a fishy odor. On the other hand, FSS had reddish brown color and sour taste by the production of lactic arid during storage.

• Korean journal of food and cookery science
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• v.29 no.3
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• pp.291-300
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• 2013

This study was conducted to develop the optimum mixing rates of a functional instant pumpkin gruel including pumpkin powder and to have the high preference to all age groups. The produced of this study were to optimum the composite recipe by making instant pumpkin gruel, respectively, with the different 16 experimental point with 3 replicates of the weight of pumpkin powder ($X_1$), roasted soybean flour ($X_2$) and gelatinized rice flour ($X_3$), and by quantities of the using response surface methodology(RSM). The color, pH, viscosity, and sensory characteristics(appearance, color, flavor, taste, viscosity, overall acceptability) were dependent parameters. The color of instant pumpkin gruel L value decreased with increasing amounts of pumpkin powder and a value and b value increased. pH and viscosity increased with increasing amounts of pumpkin powder and roasted soybean powder. The optimal mixing percentage of pumpkin powder, roasted soybean flour and gelatinized rice flour were 5.25 g, 3.00 g and 4.50 g for overall quality of 5.72 g, 4.30 g and 3.00 g for maximum score of overall organoleptic quality, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.3
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• pp.293-300
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• 2016

In the present study, we investigated the quality, sensory characteristics and commercialization potential of a rice collet snack made with the addition of dried shrimp. “Mild” and “spicy” snack products were produced with an edible oil coating and mixed seasoning powder coating, respectively. The approximate composition of the mild and spicy snacks, respectively, were 2.44% and 2.24% for moisture, 8.52% and 8.64% for crude protein, 18.36% and 26.54% for crude lipids, 1.28% and 1.38% for ash, 1.1% and 1.2% for salt, and 0.61 and 0.62 for pH. The L (lightness), a (redness), b (yellowness), and ⊿E (color difference) values were higher for the mild snack than the spicy snack. The mild and spicy snack had values of 7,776.4 and 7,655.8 mg/100 g for total amino acids, and 221.6 and 253.5 mg/100 g for total free amino acids, respectively. The TBA (thiobarbituric acid) value did not differ significantly between the two types of snack. The hardness value of the spicy snack was higher than that of the mild snack, but there were no significant differences in flavor between the two products. The sensory evaluation score of the spicy snack was slightly higher than that of the mild snack. Organoleptic inspection indicated that both snacks had a favorable, unique taste.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.747-753
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• 2006

Tea was known to have different taste and flavor with leaching temperature and time. This study was designed to optimize leaching condition for green tea bag that has been popular to consumers. Soluble solid, total phenolics, and total flavonoid content increased as leaching temperature and time increased. The ranges of maximum leaching condition for these components were $96.1{\sim}99.0^{\circ}C\;and\;5.7{\sim}6.8\;min$. As leaching temperature decreased and leaching time increased, however, electron donating ability (EDA) increased and showed the highest values at $65.3^{\circ}C$ and 7.2 min. The overall acceptability was maximal at $70.2^{\circ}C$ and 3.1min. Based upon the physicochemical and organoleptic properties, it was predicted that the optimal range of leaching conditions for green tea bag was $73{\sim}83^{\circ}C\;for\;5.3{\sim}6.3\;min$.