• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.288-295
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• 1999

Nineteen japonica and Tongil-type rices were selected from seventy nine Korean and Japanese rice cultivars grown in 1989 based on the water uptake behavior of milled rice under the room temperature and boiling conditions. The selected rice cultivars were investigated for water absorbability and some physicochemical characteristics of milled rice, proper water amount for cooking and sensory evaluation of cooked rice. The relationships among the tested grain properties were also examined. The highest varietal variation of water uptake rate was observed at twenty minutes after soaking in water. The maximum water uptake of milled rices at room temperature occurred mostly at about eighty minutes after soaking in water. Newly harvested rices showed a significantly lower water uptake rate of milled rice at 20 minutes after soaking, a relatively higher maximum water absorption ratio under the room temperature, and the less water uptake and volume expansion of boiled rice compared with the one-year old rice samples. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice ansd the palatability of cooked rice. The water/rice ratio(in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was averaged to 2.63(in v/v basis). The water amount needed for optimum cooking was the lowest in Cheongcheongbyeo (Tongil-type rice) and the highest in Jinbubyeo, and the amount could be estimated with about 70% fittness by the multiple regression formula based on some water uptake characteristics, ADV and amylose content of milled rice as the independent variables. Nineteen rice cultivars were classified into seven groups based on scatter diagram projected by principal component analysis using eight properties related to water uptake and gelatinization of milled rice.

• Food Science and Preservation
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• v.8 no.4
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• pp.379-384
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• 2001

This study was conducted to investigate the changes in quality of soybean sprouts grown by ozone treatment during storage. Soybean spouts were cultivated under conditions of ozone water watering after soaking in water (W/W), watering after soaking in ozone water (O/W), ozone water watering after soaking in water (W/O) and ozone water watering after soaking in ozone water (O/O). The ozone concentration in soaking of soybean and watering of soybean sprouts was 0.3 ppm, respectively. No significant difference in shelf-life between W/W soybean sprouts and ozone treated samples showed. But shelf-life of soybean sprouts stored in 0.01 ㎜ polyethylene film at 10$\^{C}$ and 20$\^{C}$ prolonged 4 and 2 days, respectively. The slow growth of total microbe in the ozone treated samples stored at 10$\^{C}$ was observed, whereas that of products at 20$\^{C}$ showed rapid growth during storage. However, no great difference occurred among samples in the changes of moisture, vitamin C and chlorophyll content during storage. Higher hardness of soybean spouts stored at 10$\^{C}$ and 20$\^{C}$ was kept in the O/W and W/O products. Color, flavor and overall acceptability evaluated by sensory teat during storage had higher scores in O/W products as compared to the other samples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.2
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• pp.85-94
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• 1988

This experiment was carried out to obtain the basic data for removal the astringency and off-flavor in soybean milk, by means of soaking of soybean in NaOH and $NaHCO_3$ solutions. The changes of phenolic compounds in soybean during soaking were investigated with HPLC and also the changes of flavor and sensority of soybean milk, prepared from soaked soybean were studied. Phenolic compounds of soybean were identified as chlorogenic, p-hydroxybenzoic, p-coumaric, ferulic and gentisic acid and, chlorogenic acid content was greater than the others. The chlorogenic acid of soybean was mainly neutral type and the other compounds were almost acidic type. Up to 85% of the chlorogenic acid was removed by soaking of soybean in 0.1% of NaOH solution for 8 hrs. Phenolic compounds of soybean was almost removed by soaking in 0.1% of NaOH solution at $90^{\circ}C$ for 1 hr. Chemical composition of soybean milks prepared from soaking of soybean in water, 0.1% NaOH and 0.5% $NaHCO_3$ solution were similar. Hexanol content of beany flavor in soybean milk was increased by soaking of soybean in NaOH solution, where as hexanal, propanal, pentanal contents were removed up to 60%. Color of soybean prepared from soaking of soybean in NaOH solution at high temperature were deep yellow but were high whiteness in soybean milk prepared from soaking of soybean in water at low temperature. Sensority of soybean milk prepared from soaking of soybean in 0.1% of NaOH solution at $90^{\circ}C$ for 1 hr was more favorable than the others.

• Korean journal of food and cookery science
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• v.7 no.4
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• pp.71-86
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• 1991

This study was attempted to enhance nutritional value of cooked rice by adding milk in cooking water. Cooked and soaked rice with five different levels of milk in cooking water (0%, A: 30%, B: 50%, C: 70%, D: 100%, E) was tested for rheological parameters, fine structural changes, sensory evaluation. 1. Water absorbance of raw rice in cooking water with varying amountes of milk, was tested at $5^{\circ}C$ and $15^{\circ}C$ for 2 hours. Water absorption ratio was decreased as milk content was increased and soaking temperature was low. Time for maximum water absorption of sample A was 40 min at 1$15^{\circ}C$ but for sample B to D, it was not reached until 120 min. 2. Electronmicroscopic observation revealed that starch granules of rice lost their regular forms by soaking for 90 minutes, but recovered most of initial regularity after 24 hours. Increase in milk content of soaking water decreased marginal sharpness of the starch granule, presumably due to reduced swelling of the granule. 3. Degree of gelatinization of cooked rice was highest in sample A and progressively decreased as milk content was increased. It was, however, increased in all samples when the cooking water to rice ratio was raised from 160% to 180%. During 4 hour storage, rates of retrogradation were not different between A and B samples, but those of C, D and E were about 2.5 times higher than A and B under the optimal condition of 170% cooking water to rice ratio. This was in the order reverse to hardness order of AC>A, D＞E at cooking water to rice ratios of 160% and 170%, above which A sample surpassed the rest of samples. 4. Sensory evaluation conducted by fifteen university students as panelists showed that there were more significant differences among five samples in flavour, texture than appearance and a notable preference for b and C over A, D and E.

• Applied Biological Chemistry
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• v.33 no.1
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• pp.18-23
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• 1990

Seven varieties of soybeans(Paldal, Danyeob, Jangbaek, Baegun, Jangyeob and 2 cultivars of Local 1 and Local 2) were investigated to compare the water uptake properties and volume changes during soaking in water. The hydration properties showed that the equilibrated weight increase ratio decreased as the soaking temperature raised to higher than $40^{\circ}C$, while the initial water uptake rate increased upto $80^{\circ}C$. The increase in hydration showed a linear relationship with the square root of the soaking time at $4^{\circ}{\sim}60^{\circ}C$. Local 1 was the highest in water uptake rate constant while Local 2 was the lowest. The activation energy calculated was in the range of $3,246{\sim}4,694\;cal/mole$. The Jangbaek and Local 1 were the highest and the Paldal was the lowest in the rate of volume increase. The activation energy for volume increase was in the range of $3,310{\sim}4,190\;cal/mole$. The z-values calculated from volume change was a little higher than those obtained from weight change.

• Korean journal of food and cookery science
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• v.20 no.6 s.84
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• pp.630-636
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• 2004

The effects of soaking and steaming time on the quality characteristics of Korean rice cake (karedduk) were investigated. As the soaking time increased, the water-binding capacity and rice floor solid content also increased. After 8 to 10 hr soaking, 75.2 to $76.8\%$ of particles were smaller than $40\;{\mu}m$, and 23.2 to $24.8\%$ within the range of 40 to $100\;{\mu}m$. Therefore, an extended soaking time reduced the particle size. Texture is an important characteristic used to differentiate karedduk varieties, and is considered by the consumer as a determinant of the overall quality and preference. The hardness, cohesiveness, gumminess and chewiness of the karedduk structure decreased with increasing steaming time, but the springiness was highest after a 40 min steaming time. The overall texture properties were also more acceptable with 8 and 10 hrs soaking times. The L value of the karedduk decreased with increasing steaming time, but the b value increased. Also, the results of the sensory evaluation showed that an 8 hr soaking time and 40 min steaming time produced more acceptable karedduk in terms of whiteness, texture, springiness, chewiness and overall acceptability.

• Korean journal of food and cookery science
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• v.17 no.4
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• pp.309-315
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• 2001

The effects of soaking time of nonwaxy rice and particle size of rice flour on the properties of nonwaxy rice flour after steeping at room temperature were investigated. Nonwaxy rice was soaked at 20$^{\circ}C$ for 0, 1, 12, or 24hr, dried at room temperature and milled. Nonwaxy rice flours were passed through 45 mesh or 100 mesh sieve, and were compared for the properties depending on the particle size and soaking time. The particles of rice flour were separated into 10$\mu\textrm{m}$∼30$\mu\textrm{m}$ and 40$\mu\textrm{m}$∼80$\mu\textrm{m}$ groups, and the amount of large particle size(40$\mu\textrm{m}$∼80$\mu\textrm{m}$) was greater in the flour sieved through 45 mesh than 100 mesh sieve. The protein and ash contents decreased and amylose contents increased as the soaking time increased. The water-binding capacity increased rapidly up to 1 hr of soaking and increased slowly thereafter. The swelling power and the solubility increased with temperature rising in the range of 65$^{\circ}C$∼95$^{\circ}C$, and these two properties increased rapidly up to 12 hr of soaking. Peak viscosity and breakdown of the pastes prepared with 12 hr-soaked nonwaxy rice flour were higher than those with 1 hr-soaked ones, while the setback and viscosity at 95$^{\circ}C$ of 12 hr-soaked ones were lower than 1hr-soaked ones.

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.575-582
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• 1989

An investigation was carried out to improve the quality and yield of barley tea(water extracts) by modifying the roasting method. The modified methods employed were crushing the barley into 4-10 parts and soaking in water at room temperature for 20 minutes followed by roasting (light brown or dark brown) at $250^{\circ}C$ before boiling with water. The varieties of barley used for this study were Ol-bori(with hulls) and Youngsan-bori(without hulls) and the qualities measured were the physical, chemical and sensory characteristics of roasted barley and its extracts. The results showed that the higher solid yields in barley tea was obtained with an increase in soaking and roasting time. The solid yields increased rapidly with extraction time in boiling water until 30 minutes and then slowed down thereafter. However the intrinsic viscosity of barley tea was reduced by increase in soaking and roasting time. The color of barley tea expressed as Hunter L, a, b values showed that lower L value and higher a and b values were measured for those prepared without soaking and with more extensive roasting. Organoleptic evaluation clearly showed that the sensory quality of barley tea was significantly improved in intensity of odor and taste by crushing, soaking and dark brown roasting.

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.492-498
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• 1987

Dried soybeans (varieties: Saeal, Kwanggyo, Tanyob) took up water rapidly for first 3hr followed by a slower rate of uptake. The beans took up an equal weight of water (100% hydration)after approximately 3.5hr at $50^{\circ}C$, 5hr at $30^{\circ}C$ and 7.5hr at $20^{\circ}C$ respectively. pH of the soaking solutions decreased during the soaking period. This was undoubtedly caused by the ionization of the cellular components resulting in increased levels of hydrogen ions in the liquor. Soluble solids were leached out of the beans at fairly steady rate throughout the hydration and the amount was greater with higher temperature. This amounted to 0.4-0.7g at $20^{\circ}C$ and 10.2-15.0g at $50^{\circ}C$ per 100g soybeans. Temperature was the most important factor in determining the rate of water absorption and of solid losses. Of the total solids lost, 12-25% was protein. The proportion of protein loss increased as the soaking time and temperature increase. Amount of protein loss was 80-200mg at $20^{\circ}C$ and 440-480mg at $50^{\circ}C$ after 24hr soaking per 100g soybeans. About 5% of soluble sugars, including fructose, sucrose, raffinose, and stachyose, was removed from the beans after 24hr soaking at $20^{\circ}C$.

• Mass Spectrometry Letters
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• v.12 no.3
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• pp.106-111
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• 2021

Several pretreatment methods have been developed to reduce the inorganic arsenic, which is known to be highly harmful to humans, among various arsenic species present in hijiki and rice. The pretreatment methods were selected and developed as methods that can be non-harmful even after treatment and easily applied. Hijiki was applied by two methods. One was soaking in water at room temperature for various durations and the other was boiling of it in water for a short period of time. Rice was soaked in water with different rice-to-water ratios for various durations. The most effective method that reduced the inorganic arsenic in hijiki was to repeat parboiling for 5 minutes twice, which led to 79% reduction of the inorganic arsenic in it. In the case of rice, soaking for 24 hours at the ratio of 1:5 (rice:water) resulted in 51% reduction of inorganic arsenic in rice.