• The Korean Journal of Food And Nutrition
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• v.20 no.3
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• pp.289-294
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• 2007

For the purpose of developing a functional yogurt, a new type of yogurt was prepared. To manufacture this new yogurt, 12% skim milk was added to the hot water extract of black soybeans. The yogurt was then evaluated for its acid production(pH and titratable acidity), number of viable cells, viscosity, quality-retention properties, and sensory properties. The titratable acidity of the yogurt with the added 5% black soybean hot-water extract was higher(2.07%) than that of the yogurt without the added extract(1.80%). The viscosity of the yogurt made by adding 5% black soybean hot-water extract was higher(5,040 cps) than that of the yogurt made with only skim milk(2,740 cps). Lactic acid bacteria propagation was stimulated by the addition of the 5% black soybean hot-water extract. When the yogurt prepared with the black soybean hot-water extract was kept at $7^{\circ}C$ for 14 days, its quality-retention was comparatively good. Finally the overall sensory score of the yogurt made with the added 5% black soybean hot-water extract was slightly lower than that of the yogurt made with only skim milk.

• Korean journal of food and cookery science
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• v.25 no.3
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• pp.337-344
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• 2009

The principal objective of this study was to determine the optimal mixing conditions of three different amounts of small black soybeans, sugar, and plain yogurt, for the preparation of a small black soybean smoothie. The experimental design utilized herein was based on the Central composite design methodology of response surface, which included 16 experimental points, including 2 replicates for the small black soybeans, sugar, and plain yogurt. The physiochemical and sensory properties of the test were measured, and these values were applied to the mathematical models. A canonical form and perturbation plot showed the influence of each ingredient on the mixed final product. The L value and a value decreased with increasing quantities of small black soybeans, but the b values increased with greater additions of small black soybeans. Sweetness increased with increasing amount of added sugar. The results of sensory evaluation showed very significant values for color (p<0.01), taste (p<0.05) and overall quality (p<0.05) in the predicted model. As a result, the optimum formulations by numerical and graphical methods were calculated as follows: small black soybean 79.46 g, plain yogurt 275.07 g, sugar 21.20 g.