• Journal of the East Asian Society of Dietary Life
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• v.6 no.3
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• pp.325-333
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• 1996

Potato slices were dipped in calcium choreide ar chitosan solutions or and preheated in each of these solutions. In order to prevent the quality deterioration while they were refrigerated for 4 weeks at 5$^{\circ}C$ Changes in degree of browning and other quality factors were determined while they were refrigerated for 4 weeks at 5$^{\circ}C$ During refrigeration, L values were decreased and optical density (A420) were increased. But L values were increased and A420 were decreased by dipping or preheating. The contents of vitamin C were decreased. however, the loss of vitmin C were the lowest in calcium chloride treaed potato slices(CaPS). And there were no combined effects of dipping and preheating during refrigeration. However, protein content of CaPS increased but that of other treated potato slices were decreased compared to that of control. With respect to changes in other physicochemical qualit, pH increased in chitosan treated potato slices(ChPS) and loss of weight was the lowest in combined with preheating. From these results, it was considered that the shelf-life of potato slices could be increased by dipping or-and preheating.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.1
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• pp.85-90
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• 2005

A downstream process was developed for the production of yeast extract from brewer's yeast cells. Various downstream processing conditions including clarification, debittering, and the Maillard reaction were considered in the development of the process. This simple and economic clarification process used flocculating agents, specifically calcium chloride ($1\%$). After the clarification step, a Maillard reaction is initiated as a flavor-enhancing step. By investigating the effects of several operation parameters, including the type of sugar added, sugar dosage, glycine addition, and temperature, on the degree of browning (DB), giucose addition and reaction temperature were found to have significant effects on DB. A synthetic adsorption resin (HP20) was used for the debittering process, which induced a compositional change of the hydrophobic amino acids in the yeast hydrolysate, thereby reducing the bitter taste. The overall dry matter yield and protein yield for the entire process, including the downstream process proposed for the production of brewer's yeast extract were 50 and $50\%$, respectively.

• Current Research on Agriculture and Life Sciences
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• v.31 no.4
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• pp.240-244
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• 2013

To evaluate utilization of persimmon peels as novel bio-materials, the general composition and antioxidant activities of Daebong persimmon vinegar (DPV), Daebong persimmon peel vinegar (DPPV) and commercial persimmon vinegar (CPV) were investigated. The pH of DPPV had slightly higher than that of other vinegars. The titratable acidities of vinegars were 3.24% (DPV), 2.77% (DPPV) and 7.78% (CPV), respectively. The reducing sugar contents showed that DPV had slightly higher than that of other vinegars. The browning degree of DPV was lower than CPV in contrast to the turbidity. The results of Hunter's color value have showed that overall values of CPV had significantly higher than DPPV and DPV. The total phenolic contents of DPV and CPV were 19.49 and 17.13 mg/100g GAE, respectively. The total flavonoid contents of DPPV (8.04 mg/100g CE) were two fold higher than that of DPV (3.85 mg/100g CE). The antioxidant activities, by DPPH and FRAP assays, of DPV showed stronger than those of other vinegars. Free sugars were mainly composed of fructose and glucose. Organic acids were presented in the order acetic acid, succinic acid, malic acid, tartaric acid, citric acid and oxalic acid. These results suggest that the Daebong persimmon peels could be utilized for vinegar production as a health-benefit material.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.4
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• pp.284-288
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• 2001

Water deficit is a serious constraint to soybean [Glycine max L. (Merr.)] production in rainfed regions of Asia, Africa, and America. This study was conducted to develop a simple and effective screening method for drought tolerance in soybean. Fifteen soybean cultivars, eight identified to be drought-tolerant and seven drought-sensitive in previous studies, were used for the evaluation of drought tolerance under the new screening conditions. The seedling screening method was consisted of a treatment in a PEG solution and drought treatment in parafilm-layered pots. 5-day-old seedlings were treated in a 18% PEG solution for 4 days and their wilting and hypocotyl browning were recorded. Three seedlings grown in a parafilm-layered pot containing peat moss were drought-stressed by withholding water from the third day after seedling emergence, and root and seedling growth were examined. Degree of drought tolerance were rated based on seedling vigor in the PEG solution and drought-stressed parafilm-layered pots, and also on the penetration ability of roots through parafilm layer. Most of seedlings of the drought-tolerant cultivars showed higher vigour and root penetration than those of the drought-sensitive cultivars under the new screening conditions. Our results indicate that the new method can be used as a simple and effective screening procedure for drought tolerance in soybean breeding programs.

• Korean Journal of Food Science and Technology
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• v.25 no.3
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• pp.282-287
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• 1993

The effect of ethanol concentration for extraction of cinnamon on chemical and physical properties of the extracts was investigated. The cinnamon was extracted at $80^{\circ}C$ for 5 hours. High contents of cinnamic acid, aldehyde, eugenol and antioxidant activity were found in the extracts of $60{\sim}90%$ ethanol. Free sugar, tannin, degree of browning and total solids were measured relatively high in 70% ethanol extract while total amino acids and minerals were increased as the ethanol concentration decreased. The overall data suggested 70% ethanol as the most effective solvent for cinnamon extraction.

• Preventive Nutrition and Food Science
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• v.12 no.1
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• pp.40-45
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• 2007

The effects of drying methods on the physicochemical properties of chaga (Inonotus obliquus) mushroom powder were investigated. Scanning electron micrograph revealed that freeze drying produced smaller particle- sized samples which in turn resulted in higher porosity than did vacuum and hot-air drying. Samples prepared by freeze drying showed a significantly higher L*-value as compared with those prepared by hot-air drying and vacuum drying (p<0.05). The lightness (L*-value) significantly decreased with increasing relative humidity and storage temperature regardless of drying method (p<0.05). The yellowness (b*-value) increased significantly with increasing relative humidity (p<0.05). Browning index was significantly lower in samples prepared by freeze drying (p<0.05) but not significantly different between samples dried by hot-air and vacuum drying. Freeze dried sample exhibited a significantly higher degree of rehydration than other samples (p<0.05) probably due to the small particle size. Water solubility of the freeze dried sample was higher than those of the other methods while swelling ratio of the same sample appeared to be lower than those of others. Freeze dried chaga mushroom powder contained significantly lower amount of total phenolics and total sugar as compared to other samples (p<0.05).

• Food Science and Biotechnology
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• v.15 no.4
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• pp.529-533
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• 2006

To produce fresh-cut fruit products of high quality, the combined effects of postharvest calcium and heat treatment on Tsugaru apple were examined. Whole fruits were treated for 20 min at three different conditions: dipping in 3% $CaCl_2$ solution at $45^{\circ}C$ or ambient temperature, or in heated water at $45^{\circ}C$. The calcium content of the apples dipped in $CaCl_2$ solution at $45^{\circ}C$ was higher than that of the control and the non-heated calcium dipping. The fruits with calcium and heat treatment showed the same pattern of respiration rates as the control did during storage. The browning degree of the apple slices increased to approximately 3% after one-day storage, but no significant difference was observed between the treated and untreated apples. The fruits with $CaCl_2$ solution dipping at $45^{\circ}C$ had higher firmness than those with calcium dipping or heat treatment alone.

• Food Science of Animal Resources
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• v.42 no.5
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• pp.849-860
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• 2022

The myofibril protein (MP) isolate-saccharide graft reactions was prepared using the Maillard reaction with saccharides. The effects of various saccharides on protein functionality and quality of the Maillard reaction were investigated and compared with those of MP. The grafting degree of the MP isolate-saccharide graft reaction was significantly higher in the reducing sugar-treated groups (lactose, glucose, fructose, and palatinose). The browning intensity of the MP isolate-saccharide graft reaction with fructose, sucrose, and erythitol was higher than that observed in the control reaction (p<0.05). MP that reacted with reducing sugars (glucose, fructose, palatinose, and lactose) had fainter bands than MP that reacted with non-reducing sugars (sucrose, erythitol, trehalose, sorbitol, and xylitol). MPs conjugated with glucose exhibited higher protein solubility. The palatinose and lactose treatments were maximum in water binding capacity, though no significant difference in oil binding capacity among the saccharide treatments was observed. The emulsion stability of the MP isolate-saccharide graft reaction with palatinose and erythitol was higher than that of the control reaction. Therefore, reducing sugars have good protein functionality in the MP isolate-saccharides graft reaction.

• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.43-50
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• 2002

To develop commercial semi-solid apple baby food, the physicochemical characteristics of apple puree in relation to different preparing methods and the effect of the addition methods of ascorbic acid on browning reaction were investigated. The preparing methods were classified into 3 groups by initial heating treatment: no heating (A), steaming at $120^{\circ}C$ (B), and blancing at $100^{\circ}C$ (C). The viscosity of tested apple puree was $2,600{\sim}5,856\;cp$, and contents of anhydrogalaturonic acid (AGA) and neutral sugar ranged $4.15{\sim}11.92\;mg%$ and $6.18{\sim}10.65\;mg%$, respectively. Among free sugars tested, level of fructose was the highest $(5.43{\sim}8.87%)$, followed by glucose $(2.11{\sim}4.23%)$, sucrose $(1.64{\sim}2.94%)$, in that order. Since small amounts of ascorbic acid were detected $(1.54{\sim}1.83\;mg%)$, it seemed to be lost by heating process in preparing of apple puree. For apple puree A, its lightness was lower and redness was higher than those of apple puree B and C. Its degree of browning of apple puree was so high that sodium ascorbic acid was added as a antibrowning agent. Puree had low sensory score and nutrient quality. The adding methods of ascorbic acid were classified into 4 groups by adding time: dipping, blending (2), heating (3), and blending + heating (4). Considering color and preference evaluation, preparing method B and adding method 2 showed the highest inhibitory activity on apple puree browning and desirable color for retort baby food. After retort sterilization, the viscosity of apple baby food was decreased from 3,477 cp to 2,294 cp, thiamin was destroyed completely, and the contents of riboflavin and ascorbic acid were decreased 41% and 21%, respectively. However, contents of free sugar and free amino acid and sensory parameter were not influenced by retort sterilization. In overall, the preparing method B-adding method 2 was a good processing condition for the retort apple baby food.

• Food Science and Preservation
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• v.10 no.4
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• pp.476-481
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• 2003

As its high functional properties to be used as medicine or food, the cultivation of Agaricus mushroom has been expanded and iぉ commercialization required better storage methods that can extend its functional and nutritional value for longer period. We selected drying as the most plausible method to meet such requirement, and several drying conditions were investigated to locate the optimum drying condition that can be used to keep the quality of mushroom. Drying temperature of 50$^{\circ}C$, 60$^{\circ}C$, 100$^{\circ}C$ were selected to trace the drying time required to achieve the moisture content of mushrooms less than 10%. The drying temperature at 50$^{\circ}C$ required 29 hrs of drying time, while 100$^{\circ}C$ required only 10 hrs of drying tune. However, their quality characteristics on the following categories, on the degree of browning and color were investigated to find the optimum drying condition. In addition, sensory evaluation was conducted to evaluate the quality of dried mushrooms produced by each drying condition. The browning of the mushroom was evidently increased as the higher drying temperature was used and 50$^{\circ}C$ drying produced the most desirable quality of all in pileus or stipe. The aeon of browning intensified by drying temperature was comparable to the result of whiteness index value, which resulted lower L values as drying temperature increased. and the 50$^{\circ}C$ drying resulted the most highest L values among all drying samples. As the browning and whiteness results implied, the sensory evaluation result gathered from the present research indicated that the 50$^{\circ}C$ drying was the most favorable drying condition by scoring the most highest average scores on flavors, color, appearance, and overall acceptability conducted by the 10 evaluation panels.