• Food Science and Preservation
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• v.14 no.6
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• pp.617-623
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• 2007

To utilize the non-heat treated alcoholic by-products of brown rice(Goami) as food sources, the quality characteristics change according to the treatment conditions of ${\alpha}-amylase$ were evaluated. It resulted that the increase of hydrolysis temperature correspondingly increased the soluble solids, total dietary fiber and total sugar in the by-products of Goami, and the highest reducing sugar content was observed at $80^{\circ}C$. The free amino acids contents were tended to slowly decrease by the hydrolysis temperature more than $70^{\circ}C$, and the highest content of oligosaccharides were detected at the hydrolysis temperature of $80^{\circ}C$. The soluble solid according to the ${\alpha}-amylase$ concentration resulted to increase with the increase of the enzyme concentration and the total dietary fiber revealed similarly showing approximately 0.65%. The high content of reducing sugars was observed at the enzyme concentration around 0.08%(v/w). Total sugars and oligosaccharides contents tend to increase as the concentration of enzyme increased, and the content of oligosaccharides acquired at the enzyme concentration more than 0.10%(v/w) maintained to show rather similar contents. The soluble solids and total dietary fiber by hydrolysis time were found to show 6.66% and 0.65%, respectively at more than 60 min of hydrolysis, and the reducing sugars and total sugars were found to be 3,600 and 4,800 mg% in all treatment groups showing no significant difference. The content of oligosaccharides was increased with the increase of hydrolysis time, and the content was similar at more than 90 min of hydrolysis by ranging around 2,100 mg%. Based upon these results, the by-products of Goami are expected to be used as various food sources showing the highest dietary fiber and oligosaccharides contents by the hydrolysis at $80^{\circ}C$ for 90 min with the addition of 0.10%(v/w) of ${\alpha}-amylase$.

• The Korean Journal of Community Living Science
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• v.21 no.4
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• pp.481-488
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• 2010

The objective of this study was the development of the preparation method of fermented turnip juice. The yields and soluble solids of fermented turnip juice were 41.2, 52.8, 56.4 and 57.4%, and 34.3, 42.4, 48.6 and 54.7 $^{\circ}Brix$ with 40, 60, 80 and 100% addition rate of turnip quantity, respectively. The major organic acids in turnip juice were succinic acid, isobutyric acid and fumaric acid, and these organic acids were decreased after fermentation. On the other hand, lactic acid, formic acid, acetic acid, propionic acid and butyric acid were produced during the fermentation. Soluble solid and pH value in fermented turnip decreased by time-dependently. Free radical scavenging activity was increased by fermentation of turnips and nitrate scavenging effects were the highest in pH 3 and increased with adding Omija or Japanese apricot. The best preparation method of fermented turnip juice was fermentation at $24^{\circ}C$ 12-15 days after adding 40% of sucrose to total quantity. As adding Omija, organic acid contents were increased and sensory evaluation was improved in fermented turnip juice.

• Korean Journal of Agricultural Science
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• v.43 no.3
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• pp.340-345
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• 2016

The kiwi fruit (Actinidia deliciosa cv. 'Hayward') should be ripened at any step during postharvest handling before consumer consumption. This is essential for freshly harvested kiwi fruit. But, this requires correct temperatures and ethylene concentrations. More testing of a newly developed ethylene generator using charcoal for commercial purposes is needed. This study was conducted to investigate the optimum storage temperatures and the effect of ethylene on the postharvest quality of kiwi fruit. Three different ethylene concentrations of 10, 50, and $100{\mu}L{\cdot}L^{-1}$ were used on fresh kiwi fruit stored at different temperatures of 10, 15, and $20^{\circ}C$. The quality changes of the fruits were assessed by sensory evaluation and by measuring firmness, soluble solids content, titratable acidity, and ethylene production. Higher storage temperatures and ethylene concentrations softened the kiwi fruit quickly and led to the rapid loss of acidity while soluble solid contents of fruit increased to a significant extent during the same storage period. Similarly, the firmness of ethylene-treated fruits stored at 20 and $15^{\circ}C$ dramatically decreased in the experiment while treated fruits stored at $10^{\circ}C$ decreased only slightly. Quality characteristics of kiwi fruits stored at 15 and $20^{\circ}C$ were better than those of fruits at $10^{\circ}C$. With regards to the effect of temperature, fruits stored at lower temperatures took a longer time to ripen and retained their quality longer. The newly developed ethylene generator maintained the ethylene concentration in the 5 kg box at $40-400{\mu}L{\cdot}L^{-1}$. The ethylene generator could also be used to soften persimmons.

• Korean journal of food and cookery science
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• v.27 no.2
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• pp.73-81
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• 2011

Two kinds of steamed sweet potatoes were dried with mild hot air to improve quality, convenience and preference as a snack. Steamed sweet potatoes were dried at temperatures ranging from 35 to $65^{\circ}C$ for 12 hr, and moisture contents, colors, texture, and taste were evaluated. The lowest moisture content was 0.25% at $65^{\circ}C$. Color values (L, a, b and ${\Delta}E$) decreased with increasing drying temperature and drying time in both chestnut-sweet potatoes and pumpkin-sweet potatoes. Reducing sugars and soluble solids increased quickly at high drying temperatures. The highest hardness value for chestnut-sweet potatoes was $26.31\;kg_f /cm^2$when they were dried at $65^{\circ}C$ for 12 hrs. Springiness and cohesiveness were higher than those in chestnut-sweet potatoes. The highest taste score was for a dried chestnut-sweet potatoes at $55^{\circ}C$ for 6 hr and a dried pumpkin-sweet potatoes at 45 or $55^{\circ}C$ for 6 hr.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.3
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• pp.325-333
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• 1996

Potato slices were dipped in calcium choreide ar chitosan solutions or and preheated in each of these solutions. In order to prevent the quality deterioration while they were refrigerated for 4 weeks at 5$^{\circ}C$ Changes in degree of browning and other quality factors were determined while they were refrigerated for 4 weeks at 5$^{\circ}C$ During refrigeration, L values were decreased and optical density (A420) were increased. But L values were increased and A420 were decreased by dipping or preheating. The contents of vitamin C were decreased. however, the loss of vitmin C were the lowest in calcium chloride treaed potato slices(CaPS). And there were no combined effects of dipping and preheating during refrigeration. However, protein content of CaPS increased but that of other treated potato slices were decreased compared to that of control. With respect to changes in other physicochemical qualit, pH increased in chitosan treated potato slices(ChPS) and loss of weight was the lowest in combined with preheating. From these results, it was considered that the shelf-life of potato slices could be increased by dipping or-and preheating.

• Horticultural Science & Technology
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• v.34 no.6
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• pp.898-911
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• 2016

Sugars play many important roles in plant metabolism and directly influence fruit quality. The effects of two edible coatings, 2% calcium chloride and 1% pullulan, on sugar metabolism in postharvest Huangguan pear fruit were investigated during cold storage. The respiration rate, sugar content and composition, sucrose metabolism enzyme activities [acid invertase (AIV), neutral invertase (NI), sucrose synthase (SS), and sucrose phosphate synthase (SPS)] and expression of the AIV gene were analyzed during storage at $0^{\circ}C$ for 210 days. Coating treatments slowed the decrease of sucrose and hexose, the respiration rate, and the activities of AIV, NI, SS and SPS, thus maintaining high total soluble solids (TSS) and titratable acid (TA) contents in the fruit. There were no significant differences in AIV expression or activity between the treated and control groups of fruits. Both of the coatings could inhibit the activities of sucrose-cleaving enzymes, thus slowing the decrease of sugar content and maintaining high fruit quality during cold storage.

• Food Science and Preservation
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• v.8 no.4
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• pp.442-448
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• 2001

The citrus juice obtained from Jeju mandarines, Citru unshiu, was filtered to remove 20% of its original volume through the hollow fiber ultrafiltration systems equipped with various pore sizes of membranes. As the results of ultrafiltration, the contents of total acids, ascorbic acid, ascorbic acid, free sugars and neohesperidin in retentate showed the tendencies of gradual decreases with the increase of membrane pore sizes from 10K to 100K daltons, but tendencies were inverted when the membrane with 500k was used. The changes of color, soluble solids, total nitrogen, amino-nitrogen, naringin and hesperidin were not consistent with the membrane pore size. Considering all the data obtained using various pen sizes of membranes, the filtration system with NMWC 500K daltons was the most effective to produce citrus juices with hither quality.

• Preventive Nutrition and Food Science
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• v.18 no.3
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• pp.203-209
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• 2013

The objective of the present study was to evaluate the physicochemical and microbial properties of the Korean traditional rice wine Makgeolli, supplemented with banana during 6 day fermentation. The alcohol contents of the control and banana Makgeolli were 17.0 and 16.5%, respectively. The pH values decreased while total acidity, total soluble solids, and color values increased throughout the fermentation process. An increase in microorganism counts throughout the 6-day fermentation period was noted in all samples. The major free sugar and organic acid detected in all samples were glucose and succinic acid, respectively. There were 39 volatile compounds detected in the control and banana Makgeolli. The major ester detected was ethyl acetate (20.037 and 22.604% for the control and banana Makgeolli, respectively). The major alcohol compounds detected were 3-methylbutanol (20.933%) and 3-methyl-1-butanol (34.325%) in the control. 2-mtehyl-1-propanol (22.289%) and 3-methyl-1-butanol (39.851%) were the highest alcohol compounds detected in the banana Makgeolli.

• Journal of the Korean Society of Food Culture
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• v.30 no.1
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• pp.97-104
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• 2015

Antioxidant activity of dropwort fermented extract (DFE) was measured according to fermentation period, and liver protective effects were examined using Sprague-Dawley rats. Total polyphenol and flavonoid contents as well as DPPH and ABTS radical scavenging activities increased up to 60~80 days and then decreased slightly. Proper fermentation time for DFE was more than 60 days and less than 80 days. Administration of alcohol to rats for 10 days at 10 mL/kg/day raised serum AST, ALT, total cholesterol, and triglyceride (TG) levels, which were then lowered by DFE and sugar liquid with the same soluble solids. While sugar liquid increased the blood lipid profile, especially TG levels, DFE had no effect due to its antioxidant activity. When TBARS content of the DFE group in liver tissue significantly decreased in a concentration-dependent manner compared to that of the ALH group (p<0.05). Liver damage was recovered by DFE treatment and was confirmed by hamatoxylin-eosin staining. These results suggest that DFE has a protective effect against alcohol-induced hepatotoxicity in SD rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.621-628
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• 2002

Effect of the thickness of packaging film on the ripening of mature-green mume (Prunus mume Sieb. et Zucc) fruit was investigated by measuring physicochemical changes of the fruit during storage. Fruits were packaged using low density polyethylene (LDPE) films with thicknesses of 20, 30, and 40$\mu$m and stored at the room temperature. The physicochemical properties such as contents of various pectic substances, molecular weight distribution of soluble pectic substances, and surface image of the fruit were determined during storage of 8 days. In general, regardless of the thickness of the films applied, a content of water-soluble pectin (WSP) in the fruit was increased during storage, but both contents of HCI- soluble pectin (HSP), and Ca and Mg in total alcohol-insoluble solids were decreased. Sephacryl S-300 gel filtration study revealed that fractions of high molecular weight HSP and WSP decomposed into lower molecular weight pectins during storage. The scanning electronic microscope also identified a significant structural change of the fruit skin over the storage time. It could be concluded from the results that fruits packaged with LDPE 30${\mu}{\textrm}{m}$ film maintained the highest physicochemical quality of green mume fruit during storage.