• The Korean Journal of Food And Nutrition
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• v.13 no.1
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• pp.71-77
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• 2000

New type yogurt base were prepared from milk added with skim milk powder or purple sweet potato, and fermented by lactic acid bacteria (Streptococcus thermophilus and Bifidobacterium infantis, 1:1, v/v). The yogurt proudcts were evaluated for acid production(pH, titratiable acidity), number of viable cell, viscosity, sensory properties, and color value. The composition of some organic acids was also analyzed by GC. The acid production slightly decrerased by addition with purple sweet potato. There was no significant difference in viable cell counts between control (yogurt added with only skim milk powder) and yogurt added with purple sweet potato, and viable cell counts of all samples were above 9.08 log cfu/ml. Viscosity of yogurt added with purple sweet potato(36,800∼46,000 centipoise) was higher than that of yogurt added with only skim milk powder(32,200 centipoise). The overall sensory score of yogurt added with purple sweet potato(38.6%, dry base) was the best of tested yogurt. The major organic acid of yogurt added with purple sweet potato was lactic acid. its content was 0.997∼1.203%. malic acid, succinic acid, oxalic acid, and fumaric acid were analyzed out a little. Lightness and yellowness decreased by addition with purple sweet potato but redness increased. Total color difference($\Delta$E) with yogurt addition with purple sweet potato and only skim milk powder were very high(above 11.46).

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.4
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• pp.395-401
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• 2012

Purpose: The purpose of this study was to research any effect on vision protecting or decreasing VDT syndrome of extracted anthocyanine from fermented purple sweet potato and blueberry. Methods: Subjects were aged 19-20 years old who do not have ophthalmic and systemic diseases and over -N4.00 D of refraction error. 40 mg of extracted anthocyanine from fermented purple sweet potato, from blueberry, and control group, placebo were dosed at separate try. After 2 hours later, subjects were directed perform visual display terminal (VDT) work for 2 hours. Objective refractive error was measured before dosing anthocyanine and after VDT work for 2 hours. Degree of head ache, eye pain and strain and subjective symptoms of neck, shoulder and waist was also examined through interviews by dividing its degree into severe, moderate, slight or none. Results: After 2 hours VDT work, vision protection effect in terms of refractive error for dominant eye was decreased by $0.031{\pm}0.21$ D in the group of extracted anthocyanine from fermented purple sweet potato, $0.006{\pm}0.32$ D in the group of extracted anthocyanine from blueberry. However, there was significantly myopic progression in the placebo group by $0.144{\pm}0.28$ D (t=2.27, p=0.03). Conclusions: It is considered that extracted anthocyanine from fermented purple sweet potato inhibits increase of refraction anomalies of dominant eye rather than non-dominant eye after VDT work.

• Food Science and Preservation
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• v.23 no.4
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• pp.538-546
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• 2016

Kochujang was prepared by replacement of rice (25%, control) with pumpkin or purple sweet potato by 0. 5, 10, and 15% (total addition ratio of rice and sweet potato=25% of sample). Effects of the addition of sweet potato on physiochemical properties of fermented Kochujang were investigated. Viable cells of yeast decreased in the sweet potato-added Kochujang at the later stage of fermentation, while there was no significant difference in the number of bacteria among the test groups. As the addition ratio sweet potato increased, ${\alpha}$-amylase activity increased while protease activity decreased. Hunter L, a, and b values of Kochujang prepared with purple sweet potato were lower than those with pumpkin sweet potato. Changes in ${\Delta}E$ value was greater in Kochujang prepared with pumpkin sweet potato than that with purple sweet potato. Oxidation-reduction potential and water activity were higher in sweet potato-Kochujang than control, but reducing sugar content was higher in control. Alcohol and amino-type nitrogen contents were higher in Kochujang prepared with pumpkin sweet potato than that with purple sweet potato, but it was not significant. Overall sensory acceptability was highest in Kochujang prepared with 10% of purple sweet potato while that with 15% pumpkin sweet potato was the least preferred.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.673-677
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• 2002

To develop a new traditional liquors using purple-fleshed sweet potato, the condition of alcohol fermentation was investigated by adding different concentrations $(5{\sim}75%)$ of cooked purple-fleshed sweet potato into mash and 10% nuruk, and fermenting for $5{\sim}15$ days. The maximum amount of ethanol (15.4%) was produced when 20% cooked purple-fleshed sweet potato and 10% nuruk were added into mash and fermented by S. cerevisiae at $25^{\circ}C$ for 15 days. The acceptability and physiological functionalities of the purple-fleshed sweet potato liquors were also investigated and compared. PSP-10 purple-fleshed sweet potato liquor prepared by adding 10% cooked purple-fleshed sweet potato into mash showed the best acceptability in the sensory evaluation test and color test $(pink{\sim}red)$; its fibrinolytic, electron-donating, and tyrosinase inhibitory activities were better than those of other purple-fleshed sweet potato liquors and wine.

• Korean Journal of Microbiology
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• v.47 no.2
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• pp.143-150
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• 2011

Lactic fermented dongchimi naengmyeun broth which has enhanced antioxidative activity was developed. During lactic fermentation of dongchimi naengmyeun broth at $25^{\circ}C$, changes of total lactic acid bacteria, pH, acidity, soluble phenolics, and anthocyanins were investigated. After 72 h of fermentation, the stronger antioxidant activities were observed in dongchimi naengmyeun broth supplemented with purple sweet potato than those of control dongchimi naengmyeun broth which showing 96.80% in DPPH radical scavenging activity, 100.82% in $ABTs^{+{\cdot}}$ scavenging activity, 7.77 in reducing power, and 6.89 in ferric reducing/antioxidant power, respectively. These high antioxidant activities related with higher contents of soluble phenolics and anthocyanins in dongchimi naengmyeun broth supplemented with purple sweet potato. The results suggest that the making of functional dongchimi naengmyeun broth by using high soluble phenolics and anthocyanins supplements such as purple sweet potato powder was possible.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.907-912
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• 1997

Physicochemical characteristics of kochujang prepared with various raw materials, were investigated during 90 days of fermentation to obtain information for the industrial production of traditional kochujang. Reducing sugar contents of kochujang increased until 60 days but slightly decreased thereafter, showing highest value for malt added group. Ethanol contents increased after 45 days and were highest in Chinese matrimony vine group, followed by purple sweet potato and malt added groups. Amino nitrogen contents increased until the 45 to 60 days of fermentation, but ammonia nitrogen contents did not change significantly during fermentation. Amino and ammonia nitrogen contents were higher in soy sauce and Chinese matrimony vine added groups. Water activities decreased slightly during fermentation and purple sweet potato added group was lowest among the groups. Consistency of kochujang decreased until the middle of the aging but after that it increased. Consistency of purple sweet potato and Chinese matrimony vine added groups were remarkably higher than that of the others. The color values tended to decrease slightly during fermentation. Purple sweet potato kochujang was low in the lightness, redness and yellowness. Results of sensory evaluation showed garlic and malt added kochujang were more acceptable than purple sweet potato added kochujang due to more desirable taste and color.

• Journal of Applied Biological Chemistry
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• v.58 no.4
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• pp.311-316
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• 2015

Yogurt was prepared with different substitution ratio [10, 30, and 50% (w/w)] of skim milk with enzymatically hydrolyzed purple sweet potato powder (EHPSPP) and fermented at $40^{\circ}C$ for 15 h. Fermentation characteristics and antioxidant activities of the yogurt were evaluated in terms of acid production (pH and titratable acidity) and lactic acid bacterial counts and DPPH radical scavenging activity, respectively. After 15 h fermentation, titratable acidity of EHPSPP yogurt was 0.80-0.89% and was lower than that (0.93%) of yogurt made without EHPSPP. The acid production and the number of viable lactic acid bacterial cell decreased with increasing the substitution ratio. The sensory score of EHPSPP yogurt prepared with 30% substitution ratio showed the highest values in taste and overall acceptability among the tested yogurt preparations. DPPH radical scavenging activity increased with increasing the substitution ratio in yogurt fermented for 12 h. The total phenolic content of 30% EHPSPP yogurt was 40% higher than that of skim milk yogurt. These results suggest that EHPSPP can be used as substituent of skim milk and the optimum substitution ratio is around 30%.

• Preventive Nutrition and Food Science
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• v.14 no.1
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• pp.54-59
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• 2009

To improve the functional and organoleptic properties of the fermented soymilk with Bacillus subtilis 2829PNU015 which has chungkukjang like flavor, functional materials from the edible plant extracts with well-known health promoting effects were examined by fibrinolytic activity and sensory evaluation. Among five samples such as Corni fructus, garlic, purple sweet potato, aged garlic, and pumpanini were tested, Corni fructus showed the highest fibrinolytic activity. The appearance and taste of the fermented soymilk (FS) was varied to the amount of Corni fructus added, and the highest acceptability of FS was observed from FS containing 1% Corni fructus extracts ($10^{\circ}$Brix) in it. Best way of applying Corni fructus to the fermented soymilk (FFS) was found to be incubating the mixture of soymilk and Corni fructus with Bacillus subtilis. FFS demonstrated dose dependent radical scavenging activities and these activities were found to be higher than those of FS at designated concentration.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.913-918
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• 1997

Taste components of traditional kochujang prepared with various raw materials, were investigated during 90 days of fermentation. The major free sugars, maltose and glucose, were higher in malt added kochujang than others. The major organic acids of kochujang were succinic and citric acids, followed by formic acid. The contents of succinic acid in the kochujang decreased during fermentation, whereas that of citric acid increased. Purple sweet potato kochujang was highest in total free amino acids. The major free amino acids were glutamic acid, serine and aspartic acid. They remarkably increased during fermentation. Among the nucleotides and their related components in kochujang, cytidine-5-monophosphate was the most abundant component at the beginning of aging period, while hypoxanthine increased remarkably during fermentation. Kochujang prepared with purple sweet potato Chinese matrimony vine contained higher amounts of organic acids and nucleotides than the others.

• Journal of the Korean Society of Food Culture
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• v.26 no.6
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• pp.734-742
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• 2011

This study was conducted to investigate the physicochemical characteristics of Eungi, which is used as a breakfast or health food. We manufactured lotus root starch and Eungi by a traditional method and discovered that the viscosity of Eungi with 4-5% starch content was similar to fermented milk. When the physicochemical properties and sensory acceptability of a Eungi beverage combined with different amounts (0.5, 1.0, 1.5, and 2.0%) of lotus root starch were investigated, consumer acceptability was highest with Eungi combined with 0.5% starch and 6% sugar. When the physicochemical properties and sensory acceptability of Eungi beverage combined with different extract bases were investigated, the acceptability of taste and texture was highest with purple sweet potato extract and the acceptability of color was highest with omija extracts.