• Korean Journal of Food Science and Technology
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• v.21 no.1
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• pp.68-74
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• 1989

The changes of the contents of chemical components and sensory evaluation of Kimchis which were prepared by addition of different amounts of garlic were investigated during fermentation at $21^{\circ}C$ for 8 days. The range of salinity of Kimchis was 1.8-2.0% The titratable acidity of Kimchis was rapidly increased with garlic contents during fermentation. Ascorbic acid was decreased with fermentation but increased with more addition of garlic. Total sugar content was decreased until third day and the free sugar content decreased to 0.8-1.1g/100g at the 8th day fermentation. It was found that lactic acid and succinic acid were relatively high among the nonvolatile organic acids. The lactic acid content increased with the addition of garlic while succinic acid was not certain. During the whole fermentation, the result of sensory evaluation suggested that Kimchis contained more than 2g garlic were more palatable and desirable than eliminated garlic.

• Korean Journal of Food Science and Technology
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• v.22 no.6
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• pp.700-706
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• 1990

The curd yogurt was prepared from milk or milk added with skim milk powder or soy proteins. Acid production by lactic acid bacteria in milk containing additive of 2% was investigated and quality of curd yogurt(sensory property and keeping quality) was examined. Some organic acids in curd yogurt were analyzed by HPLC. The soy proteins, particularly defatted soy flour or soy flour, stimulated acid production by lactic acid bacteria more than skim milk powder. Among the 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 and acetic acid markedly increased during the fermentation by L. bulgaricus for 24 hours while the amount of citric acid markedly decreased. The major organic acid produced during the fermentation was lactic acid. Addition of soy proteins to milk reduced sensory property of curd yogurt. Among the soy proteins tested, soy protein concentrate or soy protein isolate added sample showed better sensory acceptability than other samples. When curd yogurt was kept at $5^{\circ}C$ for two weeks, titratable acidity, pH and number of viable cells of curd yogurt were not changed.

• Food Science and Preservation
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• v.22 no.3
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• pp.421-427
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• 2015

Oriental melon (Cucumis melo L. var. makuwa) has been widely consumed as various processed foods, such as dried products, jelly, wine, juice, and vinegar, in Asian countries. In fruit processing, blanching and pressure treatments affect its quality, such as antioxidant activities, sensory characteristics, and etc. This study was conducted to evaluate the effects of blanching and pressure pre-treatments on oriental melon wine-making (BP, blanching and pressure filtration; BNP, blanching and non-pressure filtration; NBP, non-blanching and pressure filtration; and NBNP, non-blanching and non-pressure filtration). Physicochemical properties and antioxidant capacities by ${\alpha}$, ${\alpha}$-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, ferric ion reducing antioxidant power (FRAP) assay, and total phenolic and total flavonoid contents were measured for comparison of the different pre-treatment methods. After the aging process, the alcohol contents and pH values showed no statistical differences, whereas the amount of soluble solids, reducing sugar, and titratable acidity were slightly different among the pre-treatments (p<0.05). The samples with blanching pre-treatment showed higher antioxidant capacities than those of other pre-treatments. In the sensory evaluation, the BNP was the best in overall acceptability. Thus, this study showed that the blanching treatment enhanced the antioxidant capacities and sensory qualities of the oriental melon wine.

• Food Science and Preservation
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• v.18 no.5
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• pp.706-713
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• 2011

This study was conducted to investigate the chemical characteristics of Gochujang with different amounts of sweet persimmon powder added during fermentation at $20^{\circ}C$ for 90 days, in an effort to improve its taste and organoleptic quality. The moisture content was shown to be inclined to increase in all the treatments throughout the fermentation. There was no significant difference between the paste with sweet persimmon powder and the control. The pH showed a tendency to decrease with increased fermentation time in all the samples during fermentation, keeping a pH range of 4.64-4.67 after 60 days of fermentation. On the contrary, the titratable acidity increased during fermentation, showing a level of 0.147-0.156 mg% in the paste with sweet persimmon powder on the 90th day of fermentation. The sugar content was shown to be $33.67-39.67^{\circ}Brix$ in the early stage of fermentation, revealing a tendency to in crease with an increase in the amount of sweet persimmon powder added. The amino-type nitrogen content was at the 241.27-245.47 mg% level in the early stage of fermentation, and appeared to be significantly high (p<0.05) in the treatments with 3 and 4% sweet persimmon powder added, respectively, after 60 days of fermentation. The content was within the range of 357.47-371.53 mg% on the 90 th day of fermentation in the final stage, showing an increase trend throughout the fermentation. The alcohol content gradually increased with an increase in fermentation time, showing a range of 0.94-0.10% on the 90th day of the final stage of fermentation. Moreover, the content was highest (0.96-0.108%) on the 70th day of fermentation, demonstrating a trend to slightly decline in all the treatments thereafter.

• Food Science and Preservation
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• v.19 no.5
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• pp.712-719
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• 2012

In this study, the physicochemical and physiological activities of 10 different commercially available juices (apple juice-A: cloud type; apple juice-B: clear type; blueberry juice; grape juice-A; grape juice-B; orange juice-A; orange juice-B; pineapple juice; pomegranate juice; and tomato juice) were investigated. The average pH, titratable acidity, Brix, and reducing sugar were 3.57, 0.57%, $13.1^{\circ}Brix$, and 57.58%, respectively. The total polyphenol and flavonoid contents were within the ranges of 98.29-878.12 ug/mL and 23.82-156.63 ug/mL, respectively, and pomegranate juice showed the highest content, followed by blueberry juice and apple juice-A. In the DPPH radical scavenging assay, apple juice-A, grape juice-A, and pomegranate juice exhibited the highest activity (greater than 90%) while orange juice-B, pineapple juice and tomato juice showed the weakest. The tyrosinase inhibitory effect was highest in apple juice-A, followed by orange juice-A and blueberry juice. The reducing power was highest in pomegranate juice and lowest in pineapple juice and grape juice-A. The antioxidant activity by reducing power was highly correlated with the total polyphenol content.

• Food Science and Preservation
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• v.20 no.5
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• pp.608-613
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• 2013

The physicochemical characteristics and antioxidant capacities of 15 red wines (Cabernet Sauvignon) from the US (5) and Chile (10) were investigated. The contents of soluble solid, reducing sugar, titratable acidity, and $SO_2$ were measured. Antioxidant capacities were examined by DPPH, ORAC assay, and total phenolic contents. In addition, polyphenols composition were analyzed by HPLC. The contents of soluble solid, reducing sugar, and acidities were 7.03~8.6 $^{\circ}Brix$, 2.7~6.7 g/L, and 0.7~0.8%, respectively, and showed no differences between wines from the two countries (p<0.05). The $SO_2$ content of Chile wines was 50% higher than that of US wines (p<0.05). Antioxidant activities by DPPH assay ranged 5.58~9.80 mM and 6.77~9.48 mM in the US and Chile wines, respectively. The ORAC values of the US and Chile wines ranged 2.17~18.08 mM and 4.55~33.77 mM, respectively. The total phenolic content ranged from 1,315 to 2,651 mg/L among the US red wines, and from 1,653 to 2,493 mg/L among Chile red wines. Gallic acid, catechin, syringic acid, p-coumaric acid, quercetin, and kaempferol were identified by HPLC. The polyphenol contents of the Chile red wines were higher than those of the US red wines(p<0.05). There were no differences in the physicochemical characteristics and the antioxidant capacities of the wines from US and Chile, but only in their $SO_2$ and polyphenol contents (p<0.05).

• Food Science and Preservation
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• v.23 no.6
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• pp.788-796
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• 2016

This study presented the change of quality characteristics of Doenjang with various salt concentrations (4, 8, 15, and 20%) during 12 months. The pHs of Doenjang during fermentation were gradually increased for 12 months, whereas the pHs of Doenjang with 4 and 8% salt increased rapidly. Titratable acidity of Doenjang with 4 and 8% salt was high at initial time, while Doenjang with 15 and 20% salt was high at the 9 and 12 months. The amino-type nitrogen content of Doenjang with 4 and 8% salt was increased and ${\alpha}-amylase$ activity of all Doenjang was decreased during whole fermentation period. The protease activity of Doenjang with 4 and 8% salt was higher than Doenjang with 15 and 20% salt until 7 months. Total aerobic bacteria number 8.0~9.1 log CFU/g for 12 months, which was steady during fermentation period. Doenjang with 8% salt showed the highest score in umami taste whereas the lowest score in bitterness, astringency, and sourness tastes between 5 and 12 months. In conclusion, Doenjang with 8% salt was a suitable concentration for low-salt fermented foods.

• Food Science and Preservation
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• v.23 no.6
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• pp.825-831
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• 2016

This study was carried out to investigate the quality characteristics of fermented milk containing Rhus verniciflua seed (RVS) extracts (0.0%, 0.1%, 0.3% and 0.5%) and antioxidant activity of RVS extracts. The proximate composition of RVS was moisture (4.76%), crude ash (1.40%), crude fat (5.33%) and crude protein (11.10%). A total polyphenol content of 70% ethanol extract of RVS ($554{\pm}2.64mg/g$) was higher than that of RVS water extract ($145{\pm}3.47mg/g$). 70% ethanol extract ($1103{\pm}6.42mg/g$) of RVS showed higher content in the total flavonoids ($37{\pm}2.30mg/g$) and activities on DPPH free radical scavenging (73.23%) and ABTS free radical scavenging (83.47%) when compared with water extracted of RVS. The quality characteristics, such as pH, titratable acidity, and the number of lactic acid producing bacteria were not remarkably different between the fermented milk samples subjected to treatments with and without the addition of RVS extracts.

• Food Science and Preservation
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• v.24 no.2
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• pp.221-229
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• 2017

The effect of sweet potato on the quality of Doenjang was investigated during fermentation. Viable cells of yeast decreased gradually after 4 weeks of fermentation, but those of aerobic bacteria increased in the late stage. Amylase activity of Doenjang was higher in the late stage of fermentation, while neutral protease maintained high activity during fermentation. Hunter L and b values of Doenjang decreased gradually during fermentation, while a value was increased. The pH of Doenjang decreased gradually until 10 weeks of fermentation, and the titratable acidity was low in the sweet potato added groups. The acid value was low in the Shinyulmi sweet potato added Doenjang. Water activity and oxidation-reduction potential of Doenjang decreased during fermentation. Reducing sugar of Doenjang decreased in the middle stage of fermentation, and it was low in sweet potato added groups. The alcohol content of Doenjang decreased after 2 weeks of fermentation. Amino and ammonia-type nitrogen of Doenjang increased during fermentation and reached the maximum after 10 and 12 weeks of fermentation, respectively. After 12 weeks fermentation, 8% of Shinyulmi sweet potato added Doenjang was more favorable taste, flavor and overall acceptability (p<0.05) than the control or the Yeonwhangmi sweet potato added groups.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.3
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• pp.353-359
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• 2011

The goal of this study was to evaluate the effects of supplementation with the needles of Pinus densiflora on the fermentation characteristics of honey wine (Pinus densiflora-honey wine). Honey without supplementation with needles of Pinus densiflora (honey wine) was included as a control. Physiochemical changes were investigated during 30 days of fermentation at $20^{\circ}C$, and following aging. At the beginning of fermentation, pH and viable cell counts of Pinus densiflora-honey wine changed rapidly, while $^{\circ}Bx$ decreased gradually. Viable yeast counts reached maximum levels at 5 to 10 days of fermentation. At day 0, the pH of Pinus densiflora-honey wine was 3.8, while the non-supplemented honey wine had a pH of 3.4. Decease in $^{\circ}Bx$ was faster in Pinus densiflora-honey wine than in non-supplemented honey wine. Supplementation of honey with needles of Pinus densiflora prior to fermentation shifted the initial pH to a more neutral pH, and the presence of Pinus densiflora needles increased the fermentation speed. The final $^{\circ}Bx$, pH, ethanol content, and total titratable acidity of Pinus densiflora-honey wine were $13.7^{\circ}Bx$, pH 3.05, 13.5%, and 0.37%, respectively. A sensory evaluation demonstrated that addition of 4% (w/v) fructose to honey wine supplemented with neddles of Pinus densiflora raised the level of product acceptability.