• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.638-643
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• 1994

Gelatinization and retrogradation properties of modified starches which were prepared by steeping sweet potato at $40^{\circ}C$ for 2, 4, 7 and 10 days were investigated. The peak temperature of gelatinization and enthalpy of untreated starch by DSC were $53.9^{\circ}C\;and\;1.32\;cal/g$, respectively, but those of modified starch were increased by steeping. In gelatinization by alkali, starches with 2, 4 and 7 day steeping showed higher viscosities than untreated starch, whereas the viscosities of starches with 10 day steeping decreased. The clarities in paste decreased during storage in all starches and decreased in starches with steeping. The degrees of retrogradation by ${\alpha}-amylase-iodine$ method were higher in starches with steeping than untreated starch. The enthalpy of retrograded starches by DSC increased by steeping except 4 day steeping starch. The sweet potato extract containing sugar inhibited the retrogradation of starch paste and the degree were higher in residual starches than in untreated starch.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.243-246
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• 2009

The axial local regression rate of solid fuel of hybrid rocket is one of important parameter for a design and performance. Steeping method is simple and measure a corrcet regression rate of axial direction not being relevant to a shape of fuel and physical characteristics. In this study, the problem of other measuring equipment was improved and this linear steeping method is provide higher accuracy than the other.

• Journal of the Korean Society of Food Culture
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• v.7 no.4
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• pp.291-296
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• 1992

The effects of steeping time of glutinous rice and of beating time of the cooked rice on characteristics of Ganjung was examined. and the optimum conditions of traditional Gangjung preparation were determined. Moisture absorption of glutinous rice was the maximum at 2 hours of steeping in water and did not increase much after then. pH of the steep water was the lowest at 7 days of steeping and increased slightly thereafter. Reducing sugar content of the steep water increased as the steepting time was extended. Expansion ratio of Gangiung was the greatest with 5 days of steepting, and tended to decrease with longer beating time. Optimum conditions of Gangjung preparation was 7 days of steeping glutinous rice and 4 minutes of beating (40 times/min) the cooked rice.

• Korean journal of food and cookery science
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• v.14 no.3
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• pp.225-231
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• 1998

Enzyme-treated glutinous rice flour, which was developed to shorten or skip a steeping process during the preparation of Yukwa, was analyzed for its physicochemical characteristics and compared with glutinous rice flour made by 28-day-steeping method. Total sugar content of the 28-day-steeped flour was the highest among all groups, on the other hand, the reducing sugar content was higher in enzyme-treated glutinous rice flour. The viscosity of enzyme-treated flours was significantly lower than that of the 28-day-steeped and particularly showed the lowest value at 65$^{\circ}C$. The contents of Ca$\^$2+/ and Mg$\^$2+/ in enzyme-treated glutinous rice flours were higher than those of the 28-day-steeped group, however, the content of P$\^$+/ was lower. Free sugar detected in glutinous rice flour prepared from 28-day-steeping method was glucose only, but enzyme-treated flours contained maltose and glucose, and the content of total free sugar was much higher than that of the 28-day-steeped group. In microscopic structure, both 28-day-steeped and enzyme-treated flours showed the particle size decreased and porous surface on some part of the flour granule.

• Korean Journal of Social Welfare
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• v.56 no.4
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• pp.103-122
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• 2004

This study is aimed to examine the process of juveniles' steeping in cyber crime for finding out data which could be applied to prevent juveniles' cyber crime and to rehabilitate the juveniles related in cyber crime. Also, this study is designed focusing on the Grounded Theory method, and 5 probationees connected with internet fraud have been interviewed as participants for this study. For the juveniles who had been steeped in cyber crime, some findings according to the analysed data have been emerged in the context of social work intervention. First, interventions need to be focused on the improvement of social environment and juveniles' crooked thoughts to prevent juvenile's Internet fraud and to rehabilitate juveniles related with Internet fraud. Second, workers need to guide the juveniles who have been indecisive on the another crime into regretting their guilty attitude in depth. Third, the prevention of juveniles' Internet fraud needs to be conducted on the level of social movement, and social work practice centers need to grope concrete programs networked with correctional authorities for the social movement.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.9
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• pp.1300-1306
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• 2011

This study investigated the physicochemical characteristics of wet-milled rice flour treated with pectinase and cellulase in a steeping process. Enzyme treatments were used as follows: pectinase 0.05%, cellulase 0.05%, and mixed enzyme treatments 0.05~0.2%. For particle distribution, rice flour E-treated with mixed enzymes (pectinase 0.05% and cellulase 0.05%) was the finest at 48.3% particle distribution less than $53\;{\mu}m$. Protein contents and damaged starch were reduced by enzyme treatments. Damaged starch was the lowest (12.1%) in rice flour E compared with non-enzyme treatment (18.1%). Amylose content, water binding capacity, solubility, and swelling power all increased upon enzyme treatments, and their effects increased upon mixed enzyme treatment. For gelatinization characteristics of RVA, peak viscosity, final viscosity, breakdown, and total setback viscosity increased in rice flours treated with mixed enzymes. Especially, in steeping method with mixed enzyme treatment, pectinase 0.05% and cellulase 0.05% treatment was suitable for minimizing damaged starch and high fine particle distribution of rice flours compared with single enzyme treatment.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.749-755
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• 2021

The objective of this study was to investigate the physicochemical properties of rice starch extracted from stale rice using alkaline steeping (AKL) and improved enzymatic digestion (iENZ) methods. The crude protein content (0.5-0.7%) of stale rice starch (SRS) was less than 1% by iENZ, but not so when measured by the existing ENZ methods. SRS is an intermediate amylose rice starch. AKL-SRS and iENZ-SRS exhibited typical A-type crystal packing arrangements with similar relative crystallinities. iENZ-SRS showed higher gelatinization onset and peak temperatures with a narrower gelatinization temperature range, compared to those of AKL-SRS, indicating that iENZ annealed SRS. Thus, iENZ-SRS exhibited lower swelling power and solubility, and higher pasting viscosities with delayed viscosity development. Overall, the use of stale rice as a rice starch source could make economical production of rice starch possible, and iENZ may diversify rice starch characteristics, which expands the utilization of rice starch in food and non-food industries.

• Journal of the East Asian Society of Dietary Life
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• v.11 no.2
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• pp.131-139
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• 2001

The physicochemical and sensory characteristics of brown rice flakes by different processing conditions such as flaking Process and their heat treatments were investigated to establish the brown rice flake processing procedure. To successfully make the compressed rice grain type flakes, the most appropriate water steeping conditions were 5 hours at 60'C. The brown rice flakes by compressed flaking procedure and heat treatment with microwave toasting showed the best crispiness-texture that tested from textrometer or sensory evaluation, and there was no significant difference between the source of rice varieties. The water absorption index(WAI) of tested flakes were negatively correlated with the water soluble index( WSI) and positively correlated with bowl life. The flakes made by compressed flaking procedure and heat treatment with microwave toasting showed longer bowl life, which is the length of the time that the cereal can retain its crispness after being soaked in milk.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.731-738
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• 2021

This study investigated the physicochemical properties of rice starch isolated from broken rice using alkaline steeping (AKL) and enzymatic digestion (ENZ) methods. Broken rice starch (BRS) by AKL and ENZ possessed crude protein contents (0.6-1.4%) acceptable to commercial products of native starch and belonged to an intermediate amylose rice starch. AKL-BRS and ENZ-BRS showed a typical A-type crystal packing arrangement with small variations in their relative crystallinity. ENZ-BRS exhibited higher gelatinization onset and peak temperatures, and a narrower gelatinization temperature range than AKL-BRS, indicating that annealing occurred in ENZ-BRS. Lower swelling power and solubility were generally observed in the ENZ-BRS. ENZ-BRS also showed slower viscosity development, higher peak and trough viscosities, and lower breakdown, final, and setback viscosities, compared to those in AKL-BRS. These results are ascribed to the annealing phenomenon in ENZ-BRS. Overall, BRS from cheap broken rice using AKL and ENZ could contribute to the expansion of rice starch utilization in food and non-food industries.

• Journal of Food Hygiene and Safety
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• v.32 no.5
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• pp.389-395
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• 2017

A simultaneous determination of 5 phenolic acids (gallic acid, chlorogenic acid, caffeic acid, pcoumaric acid, trans ferulic acid) and 9 flavonoids (procyanidin b1, aspalathin, rutin, vitexin, hyperoside, isoquercitrin, luteolin, quercetin, chrysoeriol) in rooibos tea has been carried out by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). A validated analysis method in this study was applied to rooibos aqueous infusions. Rooibos tea is an antioxidant-rich tea which has anti-cancer, anti-aging, anti-inflammatory, anti-diabetic effect. Extraction yield of phenolics depends on steeping time and temperature of water. Tea infusions were prepared by placing 1 g of tea leaves or 1 tea bag in 100 mL of boiled water, and then at 3, 6 and 30 minutes intervals the infused teas were taken to carry out the analysis of phenolic contents. Another tea infusion was conducted with cold water ($25-30^{\circ}C$) for 30 minuntes. As a result, the total amount of phenolics was highest in rooibos tea steeped with hot water for 30 minutes, followed by 6 minutes, 3 minutes and cold water 30minutes and the result has statistical significance.