• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.99-104
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• 1990

The effects of concentrations of sulfur dioxide (0.16-0.20%) and steeping times (25-50hr) at $52^{\circ}C$ on the changes in pH of steep water and weight and volume of corn and starch properties were investigated. The pH of steep water increased and remained constant after steeping time of 20 hours. The degree of weight or volume gain decreased as the concentration of sulfur dioxide increased. The protein content of starch increased as the concentration of sulfur dioxide increased. Water·binding capacity of starch showed the highest value at the steeping time of 35 hours. Swell ins power and solubility decreased as cocentration of sulfur dioxide and steeping time increased. The initial pasting temperature and peak viscosity were increased and decreased, respectively, as the concentration of sulfur dioxide increased. At the same concentration of sulfur dioxide, the peak viscosity was increased and then decreased. Viscosity of starch in sodium hydroxide solution tended to decrease as the concentration of sulfur dioxide and sleeping time increased. The gel volume of starch in 3M KSCN solution was not affected by concentration of sulfur dioxide and steeping time.

• Journal of the Korean Society of Food Culture
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• v.24 no.1
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• pp.69-76
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• 2009

This study was conducted to determine the optimal cooking conditions for brown rice using an electric pressure rice cooker. The effects of steeping conditions and cooking pressure on the hydration, gelatinization, texture and palatable properties of cooked brown rice were evaluated. Based on water uptake and DSC data, the optimal steeping time and temperature for brown rice were determined to be 25 minutes and ${\sim}60^{\circ}C$, respectively. The cooking conditions for brown rice were then divided into the following 6 categories: steeping at $25^{\circ}C$ for 25 minutes and cooking at an atmospheric pressure of 1.7 (25P) or 1.9 (25HP), steeping at $57^{\circ}C$ for 25 minutes and cooking at an atmospheric pressure of 1.7 (57P) or 1.9 (57HP), steeping at $85^{\circ}C$ for 15 minutes and cooking at an atmospheric pressure of 1.7 (85P) or 1.9 (85HP). The susceptibility of cooked brown rice starch to degradation into maltose by ${\alpha}$-amylase, which is related to the degree of gelatinization and in vitro digestibility, were then determined. The amount of maltose produced by cooked brown rice samples was highest in the 57HP group, followed by the 57P and 85HP groups. Storing cooked brown rice at $73^{\circ}C$ for 24 hours resulted in significantly higher amounts of starch being degraded into maltose in the 57P, 57HP and 85HP groups than in the other groups. Textural analysis demonstrated that the 57P, 57HP and 85HP groups had significantly lower gumminess and chewiness values when compared to the other groups, and that 57HP received had the lowest hardness of all treatments. These results were confirmed by the results of the sensory evaluations. Furthermore, the 57P and 57HP groups were found to have a higher glossiness, stickiness aroma and taste score than the other groups. These findings were taken to indicate that steeping conditions and pressure exerted a positive synergistic effect on the cooking quality of brown rice. The texture analyzer also revealed that storing the cooked rice at $73^{\circ}C$ for 24 hours only led to significantly lower scores in gumminess, hardness and chewiness in the 57P and 57HP groups, which indicates that these groups underwent a lesser degree of retrogradation than other groups. Taken together, the results of the present study demonstrate that steeping brown rice at $57^{\circ}C$ for 25 minutes and a higher cooking pressure improved the palatability and in vitro digestibility of brown rice significantly.

• Food Science and Preservation
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• v.21 no.4
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• pp.500-505
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• 2014

This study investigated the effects of the steeping condition and salinity stress on the quality properties of germinated black soybean. The absorbed water content increased drastically in six hours with the increase in the steeping time and the temperature. The pH decreased as the steeping temperature increased. A gradual increase in the dissolution of the anthocyanin was observed with the steeping time. The adequate steeping conditions were found to have been six hours at $25^{\circ}C$, which showed the needed absorbed water content within a short time. The germination percentage of the black soybeans decreased with the increase in the NaCl concentration. The pinitol and total phenolics contents showed the highest values under the concentrations of 0.7% and 0.3-0.5% NaCl, respectively. The flavonoid content was highest at the 0.1% NaCl concentration. Consequently, the salinity stress during the germination of the black soybeans enhanced the pinitol content and lowered the blood sugar, which gives it an advantage as a functional food material.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.315-320
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• 2011

Germination conditions were evaluated to obtain barley containing a high content of gamma-aminobutyric acid (GABA), and quality characteristics of saccharified materials manufactured using germinated barley were investigated. Water absorption content of barley increased but pH of the steeping solution decreased with increasing steeping time at all steeping temperatures. The changes in water absorption content and pH were highest at a steeping temperature of $25^{\circ}C$. The highest GABA content was obtained at a steeping condition of $25^{\circ}C$ for 20 h. The highest GABA content was obtained for a germination condition of $5^{\circ}C$ for 36 h after steeping, resulting in an increase of 7.4 times more GABA contents than that in raw material. The pH of saccarified materials decreased but titratable acidity, amino type nitrogen content, and ammonia type nitrogen content increased during the saccharification period. GABA content of saccarified materials increased with increasing saccharification period, resulting in the highest GABA content from saccarified materials containing germinated barley.

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.393-397
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• 2004

Rice was steeped at elevated temperatures of $40,\;50,\;or\;60^{\circ}C$ for 2 hr, and physicochemical properties of starches isolated from wet-milled rice flour were investigated. Steeping at elevated temperatures slightly decreased lightness of rice starch, while increased yellowness and redness. Average granule size of rice starch was decreased by steeping treatment. Swelling power and solubility increased as temperature increased. Starch from rice steeped at $40^{\circ}C$ displayed highest swelling power and solubility. Differential scanning calorimetry data of starch obtained from steeped rice at $60^{\circ}C$ showed increased onset and peak temperatures, with narrower gelatinization temperature range, suggesting partial annealing effect. Pasting properties of starch measured by Rapid Visco-Analyzer indicated increased peak viscosity due to rice steeping at $40^{\circ}C$. Peak and breakdown viscosities decreased at $50\;and\;60^{\circ}C$, whereas setback and final viscosities increased.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.1
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• pp.31-35
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• 2016

The influence of commonly used steeping times and temperatures about mulberry tea on a-glucosidase inhibitory activity were studied. The effects of product and preparation variables on the in-cup chemical composition of mulberry tea extracts is of interest because the appearance and taste characteristics and the possible health effects of a tea liquor arise from the chemical components extracted from the leaf during mulberry tea preparation. A comprehensive study was therefore undertaken to determine the contributions of product and provide a basic data for development of high quality mulberry tea products against diabetes. Specific eight mulberry tea were collected from each region of Korea (A-I) and when it was extracted on 85℃ for 2min, a-glucosidase activity was best for 98-102%. According to various temperature and time extraction methods, this study was carried out to optimize teamaking conditions for maximal DNJ extraction from Korean mulberry tea and and it would be of particular interest for people who drink mulberry tea to control blood glucose levels.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5384-5393
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• 2015

We investigated the effects of milling degrees of rice on characteristics of the steamed rice and fermentation of rice koji as a raw material of cheongju. It was studied for 8 months about ratio of water absorption and koji charateristics according to milling degrees. The The more increasing rice milling, the less the protein contents of milled rice was continuously decreased and the lipid and ash contents were sharply decreased to until the milling degrees 20%, and then gradually decreased. When steeping the milled rice, higher milling degrees raised rapid water asorption and higher maximum water asorption, lower water temperature raised gradual water absorption and higher maximum absorption. The longer steeping time, the steamed rice milling degrees 40% showed significantly lower hardness and springness than others. Alcohol contents of the fermented mash with rice koji milling degrees 10% was lower with 16.3-16.9%(v/v) than other sample's 17.1-17.5% (v/v). The total acid contents showed that the milling degrees 10% indicated the lowest content(0.71-0.76%) and the milling degrees 30% indicated highest content(0.93-0.99%). Within the same milling degrees, As the steeping time increases, the total acid contents imcrease. In conclusion, the milling degrees influenced on physicochemical chatacteristics of rice and steamed rice condition.

• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.41-47
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• 2012

Steeping and germination conditions were investigated in order to produce barley containing a high ${\gamma}$-aminobutyric acid (GABA) content, and the changes in GABA and nutritional components before and after germination were also evaluated in this study. Water absorption rates of three barleys increased alongside both steeping time and steeping temperature. The highest GABA contents of the three barleys, 10.4-14.1 mg/100 g, were obtained from the steeping condition of $25^{\circ}C$ for 24 hr. The GABA contents of germinated barleys ranged from 14.3 to 20.9 mg/100 g, increasing by 3.9 to 14.6 times compared with raw barley. The crude lipid, crude ash and total mineral contents were slightly decreased after germination. The major fatty acids of the three barleys before and after germination were linoleic and palmitic acids. ${\beta}$-glucan contents of three barleys were slightly decreased after germination.

• Korean journal of food and cookery science
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• v.15 no.2
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• pp.185-190
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• 1999

In order to develop the techniques for isolation and production of barley starch from Youngsan variety, optimum conditions of isolation processes of barley starch was investigated. The effect of steeping temperature and time in wet-milling process was examined and the results showed that optimal steeping temperature and time were 30$^{\circ}C$ and 12 hr. The barley starch isolated under these conditions contained 5.7% crude protein, 69% starch content and 83% white value by 100 mesh process. The optimum condition of alkali treatment was showed that concentration of NaOH and treating time were 0.2% and 6 hr, respectively. To remove the fat content of barley starch, after alkali process obtained barley starch with the addition of 10% (v/v) EtOH was attempted. As the result, the barley starch contained 0.1% of crude fat. Under the optimized isolation conditions, the barley starch finally contained 0.1% protein and 95% starch content. The isolated barley starch were superior to commercial corn starch in purity and white value.

• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.30-35
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• 1995

Gamma irradiation was applied to non-glutinous and glutinous corns for improving starch isolation process. No significant changes in proximate composition of corn grains were observed by gamma irradiation. Irradiation at 1 and 5 kGy was effective for sterilizing all contaminated microorganisms of non-glutinous and glutinous corns, respectively. The moisture-uptake rate constants were increased in proportional to the steeping temperature and applied irradiation dose level. The irradiation efficacy on water absorption properties was also recognized in the corns stored for six months at room temperature. The combined use of gamma irradiation with sulfur dioxide solution was very effective for reducing steeping time. The starch yield gradually increased as irradiation dose levels increased. At 2 kGy, the sarch yield of non-glutinous and glutinous corns increased by 38% and 27%, respectively. No significant difference in Hunter's color value was observed between the starches isolated from nonirradiated and irradiated corn grains.