• Korean journal of food and cookery science
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• v.9 no.3
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• pp.210-214
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• 1993

This investigation was undertaken for the purpose of studying the physicochemical properties of rice flour made by various soaking time(1,4,6,8,12 hours) of rice. As the soaking time was longer, the lightness of rice flours increased, on the contrary its redness and yellowness decreased. Rice flours had higher swelling power and solubility by increasing soaking time, but water binding capacity decreased upon soaking of rice. Hot water insoluble amylose of rice flours was decreased, whereas hot water soluble amylose was increased as the soaking time increased. The amylograph indices indicated that initial pasting temperature of rice flours decreased, while maximum viscosity increased as the soaking time increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.752-757
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• 2000

Response surface methodology was used to optimized soaking and roasting conditions and monitor organoleptic properties of roasted Platycodon grandiflorum tea. In soaking and roasting processes based on the central composite design with variations in threonine/sucrose concentration for soaking of Platycodon grandiflorum, roasting temperature and roasting time, coefficients of determination ($R^2$) of the models were above 0.86(p<0.05) in organoleptic properties. The maximum conditions predicted for each corresponding organoleptic properties of roasted Platycodon grandiflorum tea were 1.64% threonine concentration, 137.83$^{\circ}C$ and 27.76 min in aroma, 1.46% threonine concentration, 136.1$0^{\circ}C$ and 25.19 min in taste, and 1.39% threonine concentration, 136.44$^{\circ}C$ and 29.05 min in overall flavour. The optimum condition ranges for organoleptic properties of roasted Platycodon grandiflorum tea were soaking in 1.40~1.64% threonine concentration, and roasting at 136.10~137.9$0^{\circ}C$ for 25.19~29.00 min.

• 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.

• Journal of Applied Biological Chemistry
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• v.51 no.6
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• pp.277-284
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• 2008

The objective of this study was to investigate the effect of soaking time on physicochemical properties of waxy rice, waxy rice flour and waxy rice starch. Waxy rice (WR), waxy rice flour (WRF), waxy rice starch (WRS) were soaked at $18^{\circ}C$ for 14 days and dried at $40^{\circ}C$. Dried samples were grounded and sieved using 180 mesh. Physicochemical properties of the three samples, such as swelling power, solubility, moisture sorption isotherms and pasting properties using rapid visco analyzer (RVA) and crystal pattern using X-ray diffractometer were determined. In all samples, soaking time greatly influenced moisture sorption isotherms but no typical pattern was shown. Swelling power was not greatly changed by soaking time in the three samples. Solubility increased with increasing soaking time in all three samples, indicating that some soluble particles were exuded during soaking. In RVA pasting properties, WR and WRF showed a similar pattern, while WRS showed different pasting properties, suggesting that rice protein plays a significant role in pasting properties. X-ray diffraction patterns of all three samples showed typical A-type crystal pattern suggesting that soaking did not affect crystalline region of samples.

• Korean journal of food and cookery science
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• v.8 no.3
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• pp.315-321
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• 1992

This investigation was undertaken for me purpose of studying me sensory and textural properties of Julpyun (Korean traditional rice cake) made by various soaking time (1, 4, 6, 8, and 12 hours) of rice during storage at room temperature. The storage periods were 2, 4, 6, and 10 hours. Sensory evaluation was done by a panel of 12 judges majoring in food and nutrition. The luation was repeated 3 times. Objective evaluation was done by rheometer and color difference meter. As a result of me sensory evaluation for Julpyun made by various soaking time and storage periods, mere were significant differences (p<0.001) in most of characteristics between soaking time and storage periods. Julpyun made by soaking time for 12 hours showed the most favorite tendency during storage periods. The result of textural properties measured by rheometer showed similar trend to those of sensory evaluation. By me color difference meter, L (lightness) value were increased by increasing the soaking time. There were significant differences (p<0.001) between me samples.

• Journal of the Korean Society of Food Culture
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• v.35 no.6
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• pp.582-589
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• 2020

This study was carried out to determine the optimum temperature of the jicama pickle solution by evaluating physicochemical and sensory characteristics at various temperatures. The soaking solution of the jicama pickle was prepared at different temperatures (95, 75, 50, and 25℃). During storage, the titratable acidity, Brix, and the salinity of the jicama pickles increased, and these values increased with increasing temperature of the soaking solution. The higher the temperature of the soaking solution, the lower the L and b values. In all samples, the hardness increased rapidly until the 5th day of storage, and then gradually decreased. During storage, the jicama pickles showed a high tendency to harden at soaking solution temperatures of 75 and 95℃. Sensory evaluation indicated that the taste, flavor, crispness, and overall preference of the jicama pickle were higher at a soaking solution temperature of 75℃ and above. The higher the temperature of the soaking solution, the higher the acceptability. Based on these results, we conclude that soaking solution temperature of 75°¦95℃ in the manufacture of jicama pickles had a positive effect on the reduction in tissue softening and the sensory properties of the jicama pickle.

• Macromolecular Research
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• v.16 no.5
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• pp.411-417
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• 2008

The surfaces of henequen fibers, which can be obtained from the leaves of agave plants, were treated with two different media, tap water and sodium hydroxide, that underwent both soaking and ultrasonic methods for the fiber surface treatment. Various biocomposites were fabricated with untreated and treated, chopped henequen fibers and polypropylene using a compression molding method. The result is discussed in terms of interfacial shear strength, flexural properties, dynamic mechanical properties, and fracture surface observations of the biocomposites. The soaking (static method) and ultrasonic (dynamic method) treatments with tap water and sodium hydroxide at different concentrations and treatment times significantly influenced the interfacial, flexural and dynamic mechanical properties of henequen/polypropylene biocomposites. The alkali treatment was more effective than the water treatment in improving the interfacial and mechanical properties of randomly oriented, chopped henequen/PP bio-composites. In addition, the application of the ultrasonic method to each treatment was relatively more effective in increasing the properties than the soaking method, depending on the treatment medium and condition. The greatest improvement in the properties studied was achieved by ultrasonic alkalization of natural fibers, which was in agreement with the other results of interfacial shear strength, flexural strength and modulus, storage modulus, and fracture surfaces.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.759-764
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• 2007

To investigate the effect of soaking and particle sizes on the properties of rice flour and gluten-free rice bread, wet-milled (WRF, dried at $20^{\circ}C$) and dry-milled rice flours (DRF) were passed through sieves (45 or 100 mesh). Soaking of the rice grains affected the particle size distribution of flour passed through the same size screen. The L and b values of WRF were higher than those of DRF and were not changed with decreasing particle sizes, but DRF increased L and decreased b values. The initial pasting temperatures and setback viscosities of both flours decreased with decreasing particle sizes. The swelling powers at $100^{\circ}C$ increased with decreasing particle sizes in DRF, but maintained in WRF. Starch granules were observed on the surface of flour particles in WRF. The apparent viscosity of WRF paste exhibited 3-5 times higher than that of DRF. Thus, wet milled rice flour with smaller particle sizes (${\phi}<150\;{\mu}m$) showed better properties for making gluten-free rice bread.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.770-776
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• 2000

Pasting gelatinization of acorn flours which were prepared with soaked nut and sediment at 7.8$^{\circ}C$ for 0, 1, 2, 3 and 4 days were investigated. The peak temperature of gelatinization of untreated acorn flour (0-0) by Rapid Visco Analyzer was 73.1$^{\circ}C$, respectively, but those of flours were decreased by soaking. Peak viscosity, setback and breakdown of acorn flours were increased by soaking. In addition, consistency was increased by soaking treatment. From the result of the pasting properties, gel formation ability of acorn flour was increased with increasing soaking days of acorn nut and soaking times of sediment. The gelatinization temperature examined by X-ray diffractometry was lowered with increasing of soaking days. The observation of microstructure through a scanning electron microscope revealed that gelatinized acorn flour showed loser their original shape and structure than that of with out soaking treatment (0-0). The degree of gelatinization under the fixed temperature increased with increasing soaking days. From these results, it might be concluded that the increase of soaking days and soaking times is the factor affecting the gelatinization of acorn flour.

• Korean Journal of Food Science and Technology
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• v.17 no.6
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• pp.415-420
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• 1985

In this study, changes in physical and chemical properties of glutinous rice during various soaking periods (0, 0.08, 1, 3, 5, 7, 10 days) were investigated in order to clarify the relations ship between soaking period and expansion volume in the preparation of Gang Jung. The longer the soaking period was, the greater the expansion volume of Gang Jung was. Higher maximum viscosity and breakdown in amylogram of glutinous rice flour were observed as the soaking period was increased, As the length of soaking period increased, hardness of glutinous rice and size of flour particle significantly decreased, while sweeling power and solubility of glutinous rice flour showed no significant difference. Increased length of soaking period was associated with higher fatty acidity, higher acidity of water extract and lower pH of glutinous rice flour. Control of flour particle size distribution resulted in significantly larger expansion volume of Gang Jung. Brabender's amylogram showed that the increase of expansion volume of Gang Jung associated with the increase of soaking period was related to the change of rheological properties of glutinous rice. It seemed that changes in viscometric properties of glutinous rice was attributed to the different flour particle size distribution resulted from changes in hardness of rice during soaking.