• The Korean Journal of Food And Nutrition
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• v.17 no.1
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• pp.53-59
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• 2004

To increase the nutritional and economic value of commercial peanut yogurt, a peanut yogurt was prepared by 12% skim milk added defatted peanut powder(DPP). The proximate compositions of DPP were moisture 2.3%, crude protein 31.39%, crude lipid 38.84, ash 2.89% and carbohydrate 24.58, respectively. The yogurt product were evaluated for acid production(pH, titratable acidity), number of viable cell, viscosity, color, quality-keeping property and sensory property. By addition of 5% and 10% DPP, the titratable acidity of yogurt was higher than that of yogurt not added DPP. The propagation of lactic acid bacteria was stimulated by adding 5% DPP, and the number of viable cells were about 8.9 log cfu/ml. On the other hand, the number of viable cells in control were 8.3 log cfu/ml. Viscosity of yogurt made from adding 5% and 10% DPP was higher than that of yogurt with only skim milk. When yogurt added with DPP was kept for 15 days at 5$^{\circ}C$ its quality-keeping was relatively good. As the DPP increased, L value(lightness) decreased and a value(redness) increased obviously but the b value(yellowness) of 5% peanut yogurt increased and 10% and 15% again decreased. The overall sensory scores of yogurts added with DPP showed lower than that of yogurt with only skim milk.

• Korean journal of food and cookery science
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• v.9 no.2
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• pp.123-127
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• 1993

A curd yogurt was prepared from milk added with skim milk powder or four kinds of cereal. The optimum fermentation temperature of Lactobacillus acidophilus (KCTC 2182) and changes in growth and acid production by 1. acidophilus in milk added with cereal at 2%(W/V) level were investigated. The optimum fermentation temperature of 1. acidophilus (KCTC 2182) was 39~$41^{\circ}C$. The acidify significantly increased during fermentation by L. acidophilus for 30 hours while pH significantly decreased during fermentation. The number of viable cells markedly increased until the first 18 or 24 hours of fermentation by L. acidophilus.

• Korean Journal of Agricultural Science
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• v.48 no.2
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• pp.273-281
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• 2021

These days, different types of yogurt are being manufactured by adding various starters and functional ingredients for health. The purpose of this study was to prepare yogurt added with rice followed by fermentation with two types of starters and to examine its attributes. Ten percent of skim milk powder and 0, 2.5, 5.0, 7.5, or 10% rice were mixed in water (w/v) and then inoculated with two types of starter: 1) Type A, Streptococcus thermophiles and Lactobacillus delbrueckii ssp. bulgaricus as starter; and 2) Type B, Streptococcus thermophiles, Lactobacillus acidophilus, and Bifidobacteium animalis ssp. lactis as starter. The pH of B type yogurt was lower (p < 0.05) than that of A type yogurt from 6 hours to 14 hours after fermentation. The number of microorganisms in all fermented milk showed maximum increases at 2 and 6 hours of fermentation (p < 0.05). The number of microorganisms in fermented milk peaked at 6 hours after fermentation and maintained this level thereafter. There was no effect of rice addition on microbial growth or acidity of the fermented milk. Sensory attributes of yogurt samples with and without added rice were not significantly different. This experiment showed that the production efficiency of yogurt with added rice was not different when two different types of starters were used to manufacture yogurt.

• Applied Biological Chemistry
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• v.27 no.1
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• pp.7-13
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• 1984

The effects of various nutrients added to soy milk on the growth of Lactobacillus acidophilus were investigated. Soy milk was prepared from defatted soy flour and various nutrients such as sugars, growth stimulating agents, amino acid and milk by-products. The growth curve obtained from the experiment suggested that the log phase ended after 12hr. Glucose and fructose greatly enhanced the acid production by L. acidophilus. The optimum concentration of these two sugars in the media was approximately 3% each. Among the tested growth stimulating agents, yeast extract stimulated the acid production by L. acidophilus, and the optimum concentration of this additive was approximately 0.5%. L-methionine reduced the acid production by L. acidophilus. Whey powder and skim mills powder did not significantly stimulated the growth and acid production by L. acidophilus. Concentration of protein in soy milk did not affect the growth and acid production by L. acidophilus.

• Korean Journal of Food Science and Technology
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• v.23 no.5
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• pp.587-592
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• 1991

The curd yogurt was prepared from milk or milk added with skim milk powder or four types of rice powder. Acid production by lactic acid bacteria in milk containing additive of 2% (w/v) was investigated and quality of curd yogurt (sensory property and keeping quality) was examined. Some organic acids in curd yogurt were analyzed by HPLC. Four types of rice powder, particularly brown rice, stimulated acid production by lactic acid bacteria more than control (milk yogurt). Among four organisms tested, Leuconostoc mesenteroides and Lactobacillus bulgaricus produced more acid than L. casei and L. delbrueckii. HPLC analysis of organic acids in curd yogurt showed that the amount of lactic acid markedly increased during the fermentation by L. bulgaricus for 24 hours while the amount of citric acid markedly decreased. Addition of rice powders to milk slightly reduced sensory property of curd yogurt. Among four types of rice powder tested, tongil rice added sample showed better sensory acceptability than other samples. When curd yogurt was kept at $5^{\circ}C$ for two weeks, acidity and number of viable cells of curd yogurt were not changed.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.458-463
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• 1995

A curd yogurt was prepared from milk added with skim milk powder or egg white powder(EWP). The effects of EWP addition on growth and acid production by lactic acid bacteria in milk were studied. The effects of EWP addition on quality of curd yogurt in point of apparent viscosity, sensory property and volatile aroma compounds were also investigated. Addition of PAT markedly stimulated acid production by lactic acid bacteria and stimulating effect of EWP on acid production was proportional to the amount of addition. Apparent viscosity of curd yogurt added with EWP was generally higher than that of control. Curd yogurt fermented with L. acidophilus showed thixotropic characteristics. Sensory property of curd yogurt added with EWP was evaluated as better than reference sample and sample added with EWP at 2% level was evaluated as better than other samples. Acetone, ethanol, diacetyl, butanol and acetoin were detected by gas chromatographic analysis.

• Applied Biological Chemistry
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• v.48 no.1
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• pp.60-64
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• 2005

Yogurt base was prepared from skim milk added with $0.2{\sim}1.0%\;(w/v)$ chlorella powder and fermented with lactic acid bacteria (the mixed strain of Lactobacillus acidophilus, Bifidobacterium longum and Streptococcus thermophilus) at $40^{\circ}C$ for $12{\sim}18\;h$. Quality characteristics of the yogurt were evaluated in terms of acid production (pH and titratable acidity), number of viable cells, viscosity and sensory properties. The addition of chlorella powder stimulated the growth of lactic acid bacteria and remarkably enhanced the acid production. After 12 h incubation, titratable acidity of chlorella yogurt was $1.16{\sim}1.33%$ and was higher than that (1.02%) of yogurt made with only skim milk. However, the viscosity of yogurt was decreased by the addition of chlorella powder. The sensory score of yogurt added with 0.2% chlorella powder was similar to ordinary yogurt in taste and overall acceptability. When chlorella yogurt was kept at $4^{\circ}C$ for 15 days, its quality-keeping properties except for number of viable cells were relatively good. According to sensory score and storage ability, the optimum concentration of chlorella powder was around 0.2%.

• Korean Journal of Medicinal Crop Science
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• v.6 no.4
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• pp.265-270
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• 1998

The curd yogurt was prepared from skim milk powder added with the juice, puree and powder, respectively, of the roots of Platycodon grandiflorum (Jacq.) A.DC. Twelve hours were proved to be best for fermentation of the curd yogurt, which showed 4.1 in pH and 1.15% in titratable acidity. Quality of the curd yogurt in sensory evaluation was best when 2 % of juice, 1 % of puree and 1 % of powder were added to the skim milk powder, respectively. When curd yogurt was kept at $5^{\circ}C$ for 9 days, pH decreased, while titratable acidity increased. The viscosity was highest with addition of puree 1%. After fermentation, number of viable cell was $6.2{\times}10^8/ml$ in control. $4.4{\times}10^8/ml$ in juice 2%, $3.7{\times}10^8/ml$ in puree 1% and $4.2{\times}10^8/ml$ in powder 1%. When curd yogurt was kept at $5^{\circ}C$ for 9 days, its keeping quality (pH, titratable acidity, viscosity and number of viable cells) were good.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.666-671
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• 1993

Mixtures (total solid content: 15%) prepared with whole milk added with skim milk powder and/or sweet potato and/or pumpkin were fermented with 0.205% gelatin, 2% sugar and yogurt bacteria. The fermented mixtures (curd yogurt) were evaluated for acid production (pH, titratable acidity), number of viable cell, sensory property and keeping quality. The acid production of all mixtures remarkably increased for the first 12 hours and there is no significant difference among the mixtures. The lactic acid bacteria counts in the all products after 24 hours incubation were above $6.4{\times}10^{9}cfu/ml$. In organic acids, the mixture added with skim milk powder was higher ratio of lactic acid content to total acidity than those added with sweet potato and/or pumpkin. The sensory score of mixture containing sweet potato was best but curd yogurt containing pumpkin reduced the sensory property. When each mixtures were kept at $5^{\circ}C$ for 15 days, pH, titratable acidity, and number of viable tells of yogurt were not changed.

• Food Science of Animal Resources
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• v.18 no.1
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• pp.35-41
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• 1998

The objective of this study was to examine the changes of physical properties by additions of different kinds of stabilizers milk proteins concentration, when stored at 4$^{\circ}C$ or 20$^{\circ}C$ for yoghurt. the results were summarized as follows: 1. Addition of 2% carboxyl methyl cellulose and carrageenan, gelation 0.4%, pectin and starch 0.6%, and carrageenan & pectin 0.8% in the manufacture of yoghurt increased the viscosity, water-holding capacity and protein hydration of yoghurt. 2. Addition of 3% skim milk powder, Ca-caseinate or Na-caseinate 0.6% increased the viscosity, water-holding capacity and protein hydration of yoghurt. 3. Twenty five percent of evaporation of milk promoted to build up the optimal structure of the micelles of yoghurt and improved viscosity, water-holding capacity and protein hydration of yoghurt. 4. Addition of stabilizers to yoghurt showed an increase of viscosity, water-holding capacity and protein hydration when compared with non-addition of stabilizers to yoghurt at 4$^{\circ}C$, 20$^{\circ}C$ storage for 12hrs, 96hrs followed by the decrease of it.