• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.808-817
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• 2016

In this study, we investigated the effects of pre-soaking in salt and sugar solution prior to air drying at $50^{\circ}C$ on the characteristics of dried apples. Pre-soaking solutions included single solutions of salt 2% and sugar 2%; and combined solutions of salt 2%+sugar 2% and salt 2%+sugar 5%, respectively. The effects of pre-soaking condition and drying were evaluated in terms of moisture content (MC), water activity, color, antioxidant activity determined by DPPH radical scavenging activity, shear force, microbial contents, and sensory evaluation of apple slices. The control sample without pre-soaking showed the most rapid drying rate; in addition, the single solutions showed higher MC and water activity after drying time of 120 min, as compared to combined solutions. In all samples, MC and water activity showed high correlation coefficients of 0.91 to 0.97; whereas, shear force was negatively correlated with MC and water activity. The single solution of salt 2% showed decrease in change of color, including L, a, and b values, and the number of aerobic bacteria during drying. In addition, highest antioxidant activity and values of sensory preferences were observed in the dried apple pre-soaked in single solution of salt 2%.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.116-122
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• 1990

In order to improve the shelf life of Tofu, the effect of calcium chloride or acetic acid as coagulants were investigated for microbial and physicochemical changes during the storage in different kinds of soaking solution. The soaking water of Tofu prepared from calcium chloride was found to be spoiled after 15-17 hours of storage at $30^{\circ}C$, by reaching the bacteria count to 10million per ml. The shelf life of the Tofu prepared from acetic acid was better than those prepared by calcium chloride. For the effect of soaking solution on storage life, soaking Tofu in 0.1% acetic acid was found to be more effective than soaking in other solutions of 3% NaCl or 0.1% K-sorbate. The optical density of soaking solution of Tofu increased in proportion to spoilage, and in case of soaked Tofu in 3% sodium chloride and 0.1% K-sorbate solution, it greatly increased. Titratable acidity, and amino nitrogen contents in soaking solution increased as spoilage of Tofu progressed, but pH decreased the early period, one or two days, of stored Tofu and then increased.

• Korean Chemical Engineering Research
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• v.51 no.3
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• pp.303-307
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• 2013

This study compares the efficacy of soaking and percolation pretreatments with alkaline solutions for lignocellulosic biomass. Various biomass such as rice straw and barley were pretreated by soaking processes in various alkaline solutions including sodium hydroxide, potassium hydroxide, aqueous ammonia and sodium carbonate. The enzymatic digestibility of rice straw and barley that had been pretreated by soaking in aqueous ammonia was over 80%. Eucalyptus residue, Larix leptolepis and Pinus rigida exhibited relatively low enzymatic digestibility. Nevertheless, the enzymatic digestibility of pretreated eucalyptus residue was increased by five times compared to that of the initial biomass. And, the enzymatic digestibility of the percolation pretreated eucalyptus residue was increased 12 times.

• Membrane Journal
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• v.32 no.2
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• pp.109-115
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• 2022

In this work, the effect of nonwoven support during fabrication of flat sheet membranes via nonsolvent-induced phase separation, was investigated in detail. It was found that dope solutions with low viscosity tend to penetrate through the nonwoven support during phase inversion, resulting in nonhomogeneous membranes. A simple soaking treatment of nonwoven support prevented such unwanted dope penetration, and resulted in membranes with higher water and solvent permeance performance. The dope penetration through nonwoven was more prominent in solutions with low viscosity, and the nonwoven soaking treatment not effective in solutions with high viscosity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1577-1583
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• 2012

This study was carried out to examine changes in the quality characteristics of unripe peach Jangachi made from different cultivars during storage at room temperature for 60 days. Based on the results, unripe peach Jangachi-showed decreases in pH of pulps and soaking solutions of all varieties during storage. Salinity of Jangachi tended to increase during storage, whereas it decreased in soaking solutions. Soluble solid contents decreased during storage in all varieties, both in pulps and soaking solutions. Among Hunter's color values, L values decreased, a values increased, and b values decreased during storage in all varieties. Hardness decreased for 30 days of storage and increased slightly thereafter. During storage, yeast and mold counts increased and decreased within the range from 2.30~5.55 log CFU/g, respectively. In the sensory evaluation, Madoka and Nagasawa Hakuho were evaluated as good in overall acceptability.

• 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 Science and Technology
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• v.46 no.5
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• pp.581-587
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• 2014

The antioxidant and alcohol-degrading enzyme activities of soybean sprout sugar solutions (oligosaccharide and sucrose, $50^{\circ}Bx$) were characterized under different soaking conditions. The ratio of sugar solution to sprout content was 25%, 50%, and 75% (w/w), and the soaking times studied were 1, 3, 6, 12, and 24 h. Higher 1,1-diphenyl-2-pycrylhydrazyl (DPPH) radical-scavenging activity was detected in case of the oligosaccharide solution, compared to the sucrose solution. A similar tendency was observed for alcohol-degrading enzyme activity. When the ratio of sugar solution to sprout content was 50% (w/w), the total phenol and flavonoid contents were found to be higher, compared to those observed at 20% (w/w). However, we did not observe a significant difference between 50% and 75% (w/w). Soaking time did not significantly affect the antioxidant and alcohol-degrading enzyme activities of the solutions. As a result, when oligosaccharide solution was used for soaking soy sprouts at a ratio of >50% (w/w), higher antioxidant and alcoholdegrading enzyme activities were observed.

• The Korean Journal of Food And Nutrition
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• v.23 no.4
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• pp.511-515
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• 2010

It was conducted to assess GABA(${\gamma}$-aminobutyric acid) producing capacity and vitamin contents of germinated brown rice soaked in different soaking solutions. For germination, samples were soaked in 5% glutamic acid solution and 5% lactic acid solution as test group to investigate GABA producing capacity, and samples soaked in the solution without glutamic acid and lactic acid were set as control groups(rice and non-germinated brown rice). The GABA contents of the samples were $44.80\;{\mu}g/g$ for rice, $59.90\;{\mu}g/g$ for non-germinated brown rice, $146.70\;{\mu}g/g$ for germinated brown rice, $203.20\;{\mu}g/g$ for germinated brown rice soaked in glutamic acid solution and $222.5\;{\mu}g/g$ for germinated brown rice soaked in lactic acid solution, resulting in a significant difference(p<0.05). GABA producing capacity was enhanced by the addition of glutamic acid and lactic acid in the soaking solution for brown rice germination. The GABA contents of the germinated brown rice soaked in lactic acid solution greatly increased, along with increases in niacin and vitamin E contents without losing vitamin $B_1$. In conclusion, the addition of lactic acid in soaking solution is most suitable for germination of brown rice.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.83-89
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• 2007

In our study, lactic acid bacteria (LAB)-fermented whey solutions were applied in the soybean soaking process to minimize bacterial contamination and to enrich the biologically functional components of isoflavone and $\gamma$-aminobutyric acid (GABA). Among the 11 LAB tested, Bifidobacteria infantis and a mixed culture (Lactobacillus acidophilus, Bifidobacteria lactis, and Streptococcus thermophilus; ABT-3) displaying the greatest $\beta$-glucosidase activity were selected to produce improved biologically functional soybean preparations. In the soybean soaking processing (without water spraying), the LAB-cultured 10% whey solution was used to soak and to ferment the soybeans and the fermented soybeans were finally dried by heat-blowing at $55^{\circ}C$. The processing conditions used in this study demonstrated that the final soybean product had a reduced contamination by aerobic and coliform bacteria, compared to raw soybeans, likely due to the decrease in pH during LAB fermentation. The aglycone content of the isoflavone increased up to 44.6 mg per 100 g of dried soybean by the processing method, or approximately 8-9 times as much as their initial content. The GABA contents in the processed samples increased as the processing time of soaking-fermentation proceeded as well. The soybean sample that fermented by ABT-3 culture for 24 hr showed the greatest increase in GABA content (23.95 to 97.79 mg/100 g), probably as a result of the activity of glutamate decarboxylases (GAD) released from the soybean or produced by LAB during the soaking process.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.307-313
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• 1983

Soybeans ans black-eyed peas, chosen as test samples of dry beans, were subjected to soaking and cooking treatments to develop quick cookig methods and study their effects on quality of cooked products. The results of the study are summarized as follow: 1. Of the soaking methods tested, soaking soybeans in 3% sodium bicarbonate (SBC) solution and black-eyed peas in 0.5-1% SBC solution followed by cooking them in water at $95-100^{\circ}C$ required 40 minutes and 10 minutes of cooking time, respectively. When compared to 180 minutes of cooking time for soybeans and 40 minutes of that for black-eyed peas by conventional cooking method (Control), soaking dry beans in optimum SBC solutions reduced cooking time by over 80%. 2. Among cooking methods tested, steam cooking at $121^{\circ}C$ was the most effective one in reducing cooking time of soybeans (15 min.). Black-eyed peas sacked in water required 6 minutes of cooking time in 1% SBC solution at $95-100^{\circ}C$, and 5 minutes of that in steam at $121^{\circ}C$. 3. Quality of cooked beans with optimum texture was evaluated by sensory panel and Gardner Color Difference Meter. Beans cooked in steam at $121^{\circ}C$ had better overall quality than those cooked by other methods. Beans soaked in optimum SBC solution had quality as good as control, whereas beans cooked in SBC solution had worse quality than control. 4. These results indicated that cooking time of soybeans could be drastically reduced by either steam cooking at $121^{\circ}C$ or soaking in 3% SBC solution followed by cooking in water at $95-100^{\circ}C$. Cooking time of black-eyed peas could be significantly shortened by either steam cooking at $121^{\circ}C$ or soaking in 0.5-1% SBC solution followed by cooking in water at $95-100^{\circ}C$.