• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.542-549
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• 2013

This study was conducted to investigate the chemical properties and functionality of probiotic potato juice fermented by Lactobacillus casei. Free sugar content (especially glucose) of potatoes decreased by fermentation, but organic acid contents increased by fermentation. Although the free amino acid content of Superior juice significantly decreased after fermentation, Haryeong significantly increased after fermentation. ${\gamma}$-Aminobutyric acid, a functional amino acid, was detected at high levels in all samples and slightly decreased with fermentation, but not significantly. The total polyphenol content of potato juice showed insignificant changes in all samples by fermentation. The hydroxyl radical scavenging activity of all samples was more than 90%, and most of the activity was maintained after fermentation. The nitrite scavenging ability of all samples greatly decreased with fermentation; however a SOD-like activity slightly increased with fermentation, except for Haryeong. There was a significant xanthine oxidase inhibitory effect in fresh potato juice (more than 45%) and a low loss by fermentation. From our results, most of the chemical properties and functionality of potato juice are maintained after fermentation, although free sugar content and nitrite scavenging activity decline. Thus probiotic potato juice fermented by lactic acid could be used as a functional beverage.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.9
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• pp.1278-1284
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• 2000

An experiment was performed to evaluate different methods for preserving shrimp by-products and to determine their chemical composition. In the first experiment three ratios of shrimp by-product (SBP) to molasses (6:1, 4:1 and 3:1, wet weight), and to cassava root meal (3:1, 2:1 and 1:1, wet weight of shrimp by-product and air-dry weight of cassava root meal) were investigated. The pH of the SBP ensiled with molasses at a ratio of 3:1, and with cassava root meal at a ratio of 1:1, decreased during the first week to below 4.5 and remained low up to day 56 of ensiling, whereas the pH of the mixtures with higher ratios of SBP remained above 7.0, and the material deteriorated rapidly. The dry matter decreased initially in all treatments but then increased slightly from day 28 in the treatment where shrimp by-product was ensiled with cassava root meal at a ratio of 1:1. The crude protein (CP) and ammonia-N $(NH_3-N)$ contents of the preserved shrimp by-product material ensiled with molasses at a ratio of 3:1 increased significantly one week after ensiling. The CP content then remained constant, while the $NH_3-N$ concentration continued to increase up to 56 days after ensiling. When SBP was ensiled with cassava root meal at a ratio of 1:1 the CP content of the silage increased significantly up to 21 days after ensiling and then decreased back to the original level after 56 days, whereas $NH_3-N$ increased markedly up to 14 days and then remained fairly constant up to 56 days. However, the $NH_3-N$ content was significantly higher when SBP was ensiled with cassava root meal than with molasses. A balance experiment was carried out, arranged as a double Latin-square and including 6 F1 (Large White ${\times}$ Mong Cai) castrates fed randomly one of three diets based on cassava root meal, rice bran, and fish meal (FM) or shrimp by-product ensiled with molasses (SBEMO) or with cassava root meal (SBECA) as the main protein source. Apparent organic matter and CP digestibilities were significantly (p<0.001) higher for the fish meal diet than for the two shrimp by-product diets, although CP digestibility in SBEMO and SBECA was similar (p>0.05). N-retention was significantly higher for the fish meal diet than for the SBEMO diet, which in turn was significantly higher than for the SBECA diet (p<0.01). It can be concluded that shrimp by-product can be preserved by ensiling with molasses at a ratio of 3:1 or with cassava root meal at a ratio of 1:1. Nutrient digestibility and N-retention of diets based on these shrimp by-product silages were lower than for similar diets based on fish meal, probably due to their high chitin content and inferior amino acid balance.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.266-271
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• 1994

The curd yogurt (total solid content: 14%) was prepared from milk added with skim milk powder and potato puree. Potato puree comprised 9.5. 13,8 and 17.9% (dry basis) of the milk-potato mixture, and the effect of potato on the quality of yogurt was investigated. Addition of potato remarkably stimulated acid production and propagation of lactic acid bacteria, and viable cells reached above $3.9{\times}10^{10}$ CFU/ml after 12 hours. As potato content increased, the ratio of lactic acid content to total acidity decreased, while citric acid increased. The major organic acids of yogurt were lactic acid, citric acid, and acetic acid. Viscosity of yogurt was increased in proportion to the increment of the potato content. After 24 hours of incubation, the sensory score of yogurt containing 13.8% (dry basis) potato showed better sensory acceptability. When curd yogurt added with potato was kept at $5^{\circ}C$ for 15 day, its keeping quality was relatively good. Viable cells of lactic acid bacteria and ${\beta}-galactosidase$ activity decreased rapidly at pH 1.5, and 2.5, but the group added with potato was more stable than control.

• Horticultural Science & Technology
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• v.28 no.6
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• pp.948-953
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• 2010

We evaluated the bioactive compounds including carbohydrates (CH), organic acids (OA), ascorbic acid (AA), anthocyanin (AC), and ellagic acid (EA) in the achenes, epidermis, and flesh of fully ripe strawberry fruits of the 'Maehyang', 'Seolhyang', 'Keumhyang', 'Akiheme', and 'Red pearl' cultivars. The total contents of CH, OA, AA, and AC were significantly greater in the epidermis than in other tissues, while the EA content was significantly greater in the achenes than in other tissues. The AA content of the epidermis ranged from $49.1-69.2mg{\cdot}100g^{-1}$ FW and was significantly greater than the content of the flesh, while AA was not detected in the achenes of any of the tested strawberry cultivars. The AA contents of the epidermis and flesh of the 'Maehyang' were 69.2 and $42.2mg{\cdot}100g^{-1}$ FW, respectively, and were greater than those of the other cultivars. The AC contents in the epidermis and achenes of the 'Keumhyang' were $74.0mg{\cdot}100g^{-1}$ FW and $36.7mg{\cdot}100g^{-1}$ DW, respectively, greater than those of the other cultivars. The EA content of the achenes of the 'Seolhyang' was $215.5mg{\cdot}100g^{-1}$ DW, significantly greater than those of the other cultivars. Results indicate that the antioxidant levels and other chemical compounds of strawberry fruits vary significantly among different fruit tissues. Our results also suggest that the recently introduced Korean 'Maehyang', 'Seolhyang', and 'Keumhyang' contain higher levels of antioxidants than other major June-bearing strawberry cultivars. These cultivars are feasible selections for both growers and consumers.

• Korean Journal of Food Science and Technology
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• v.44 no.3
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• pp.280-286
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• 2012

The aim of this study was to describe the effects of genetic factors on the chemical composition or metabolites of grapes harvested within the same region. Grapes were separated into pulp, skin, and seed, and physicochemical characteristics were compared among seven grape varieties. The sugar concentrations of the grape musts ranged from $15.17-20.93^{\circ}Bx$ with Seibel variety being highest at $20.93^{\circ}Bx$. pH ranges of grape musts were 3.46-4.02 and total acidity was highest with 1.05 in Steuben variety. Tartaric acid content was highest with 146.68, 500.10 mg/L in pulp and skin extract of Merlot variety. Malic acid content was highest in pulp extract of Seibel variety (1127.14 mg/L) and skin extract of Chardonnay variety (1720.06 mg/L). K content was highest with 379.13 and 828.01 mg/L in pulp and skin extract of Chardonnay variety. Ca content was highest in pulp extract of Kyoho variety (6.98 mg/L) and skin extract of Campbell Early variety (12.26 mg/L).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5468-5475
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• 2015

This present work was aimed to analyse characteristics of fermentation and aging of Korean traditional cheongju prepared by adding of different brewing water. The three different mashes were used for fermentation and maturation. The cheongju(A) was prepared without adding of brewing water in two stage mashing. Cheongju(B) and cheongju(C) were made with adding of 1 liter and 2 liter brewing water in two stage mashing respectively whereas the cheongju(B) and cheongju(C) showed higher fermentation ability than that of cheongju(A) regarding to pH, ethanol, specific gravity and sugar concentration(brix). In terms of volatile compounds content after six months aging, cheongju(A and B) prepared by adding brewing water showed the higher content of ethyl acetate than that of cheong(C) and the concentrations were maintained during the aging period. In addition, the content of fusel oil(n-propanol, i-butanol, n-butanol, i-bmyl alcohol, n-bmyl alcohol)indicated similar pattern as ethyl acetate. The organic acid of cheongju B(4873.46 mg/l) and C(4963.12 mg/l) also indicated the higher content than that of cheongju A(4661.47 mg/l). In conclusion, cheongju B and C prepared by adding brewing water in two stage mashing showed better quality and taste than that of cheongju A.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.4
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• pp.191-202
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• 2001

Experiments were conducted on established grassland sward at Gongiam, Kwangju, and Kyung-gi in Korea from 1995 to 1997. The influence of mineral-N fertilizer or animal manure(AW) on herbage dry matter(DM) yield, N yield, the recovery of AM-N, and soil N and organic matter(0M) content in the mixed sward('potomac' orchardgrass, 'fawn' tall fescue, and 'kenblue' Kentuky bluegrass) was investigated. The treatments were replicated three times in a split plot block design. AM(the main plots) was applied at 200kg N ha ' year ' on each plot. The types of AM were cattle feedlot manure(CFM), pig manure fermented with sawdust(PMFS) and Korea native cattle slurry(KNCS). Three levels of mineral-N fertilizer, as urea, ranging from 0 to 200kg N $ha^{-1}\;year^{-1}$ in 100kg increments, were superimposed on each plot. The fertilizers and AM were applied in two equal dressings(the end of March and middle of November). AM and mineral fertilizer had significant effects(p<0.05) on herbage DM and N yields. Herbage yields in KNCS were higher than those in CFM and PMFS(p

• Korean Journal of Food Science and Technology
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• v.52 no.3
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• pp.212-219
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• 2020

The physicochemical characterstics of El Salvadoran Coffea arabica cv. Bourbon coffee extracts under various roasting conditions were investigated. Green beans were roasted under four different conditions (Light-medium, Medium, Moderately dark, and Very dark). The coffee extracts were prepared by using the espresso or drip methods. As the roasting degree increased, the coffee bean moisture content decreased and the ash content increased. The lightness and yellowness of the beans and coffee extracts decreased along with the increasing roasting degree. In the drip coffee, the reducing sugar content decreased and the pH value increased along with the increasing roasting degree. Both in the espresso and drip coffee, total organic acid and chlorogenic acid contents decreased, while the caffeine content increased along with the increasing roasting degree. Therefore, it is suggested that the roasting degree affects the physicochemical characteristics of coffee extracts.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1055-1061
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• 2014

Innovative freezing technology is currently applied to preserve foodstuffs for long-term storage. Generally, the quality of frozen food is closely related to the types of freezing and thawing processes. In this study, we characterized the physicochemical properties of onions depending on freezing rate. When onions were frozen at $-40^{\circ}C$, freezing rates were 0.1, 0.5, and $0.7^{\circ}C/min$ depending on air-blast quick freezer mode. Onions were thawed by microwave irradiation at 400 W. Hardness of onion dramatically decreased after freezing and thawing compared with blanched onion. However, the fastest freezing rate did not affect hardness. Thawing loss of onion decreased with a faster freezing rate. For morphological observation, onion frozen at a faster rate showed a smaller ice-crystal size. Vitamin C content decreased upon blanching or freezing, but there was no significant difference according to freezing rate. Although free sugar content also decreased upon blanching and freezing, its highest content was at $0.7^{\circ}C/min$ freezing. Among organic acids, malic acid content was highest at $0.7^{\circ}C/min$ freezing. Based on this study, it could be suggested that a faster freezing rate is effective to improve frozen food quality in accordance with preventing tissue damage or minimizing destruction of nutrients.