• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.3
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• pp.401-406
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• 2000

In development of the processed food, it is important not only to make the food delicious but to enhance its storage span and thermal stability without change of the food quality in color, which greatly affects the tastes of customers. Protopectinase (PPase) from Bacillus subtilis EK11 hydrolyses or dissolves protopectin in the middle lamella of plant tissues with the resultant separation of plant cells from each other, called enzymatic maceration. With the PPase, Kiwifruit was enzymatically macerated to separate cells to primary cell wall without damage. Yields of kiwifruit treated with PPase and mechanical maceration were 82% and 60%, respectively. Total and reducing sugars, crude protein and fat in the enzymatic maceration were well preserved as in the mechanical maceration. Importantly, over 95% of vitamin C, which is the most unstable component in application of the mechanical maceration, remained with intact form for one day after the enzymatic treatment. When the suspensions of kiwifruit macerated with both treatments had been stored at $4^{\circ}C for 6 days, the suspension of kiwifruit mechanically macerated was decolorized. whereas decolorization was not found in the enzymatically macerated kiwifruit. Moreover, the mechanically macerated kiwifruit was greatly deteriorated after heat treatment at $100^{\circ}C for 60 min ; the cell suspension of the exzymatically separated kiwifruit appeared to be stable, indicating the thermal stability. Thus, the PPase treatment could be a better choice for preparation of the highly valuable and functional processed food of kiwifruit as well as for prolonging the preservation period of the processed kiwifruit.

• Korean Journal of Food Science and Technology
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• v.45 no.3
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• pp.350-355
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• 2013

The quality of fermented dropwort extract (FDE) and fermented dropwort vinegar (FDV) was assessed for free sugar, organic acid and free and total amino acid content. Major organic acids were lactic acid in FDE and acetic acid in FDV. Free sugars in FDE were fructose and glucose, and those in FDV were fructose, sucrose, and maltose. Aspartic acid was the major free amino acid in both FDE and FDV. Additionally, the main free amino acids in FDE were alanine and ${\gamma}$-amino-n-butyric acid (GABA), while those in FDV were arginine and valine. Moreover, to investigate the protective effects of FDE and FDV against oxidative stress induced by t-BHP and $H_2O_2$, C6 cells were treated with FDE or FDV prior to inducing the oxidative damage. FDE and FDV inhibited cell death significantly in a dose-dependent manner. These data imply that FDE and FDV may be effective in neuronal cell protection against oxidative damage.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.430-437
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• 1993

This study was carried out for high quality mirin Production by fusant F-50. Cellularly fused between Aspergillus oryzae 9-12 and Aspergillus shirousamii 6082-60. The conventional and the improvement methods in Mirin-making by F-50 showed high level of total sugar, reducing sugar and amino-nitrogen of 42%, 38% and 0.18%, respectively. Free amino acids in Mirin were found to 387.2 mg% glutamic acid, 283.8 mg% arginine, 244.0 mg% leucine, 218.0 mg% aspartic acid, 231.1 mg% alanine, 168.3 mg% serine and 148 mg% phenylalanine. Organic acids in Mirin were contained: oxalic acid, citric acid, malic acid, succinic acid, lactic acid, acetic acid and propionic acid. Sugars such as glucose, maltose, isomaltose, maltotriose, ribose, isomaltotriose and isomatotertraose were also found in Mirin. The clouding formation of Mirin made by F-50 showed 0.03 alcohol clouding, 0.08 water clouding and negative heat clouding.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.943-951
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• 2004

As storing ginger roots under optimum conditions takes high cost, ginger roots are commonly stored in underground tunnels where the maintenance of optimum temperature and humidity is difficult. One of the methods fur long term storage of ginger roots is freezing. The objective of this research was to evaluate effect of storage temperatures and packaging methods on the quality of minced ginger prepared with frozen stored ginger. The minced ginger prepared with frozen stored ginger at $-20^{\circ}C$ was packed in bags, glass bottles and tubes, and then stored at 5 and $-20^{\circ}C$ for quality evaluation at 4 and 15 week-intervals. The changes of surface color, total free sugars, free amino acids and volatile compounds were less in the combined treatment samples than in control during storage, regardless of the storage temperature. The tube packing was the best for maintaining quality of minced ginger during storage among tested packaging methods. Sensory results showed that the minced ginger with the combined treatment and packed in tubes could be stored at 5 and $-20^{\circ}C$ for 12 and 45 weeks, respectively, without a significant drop in palatability.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.419-425
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• 1988

The clarified apple juice was pre-concentrated by reverse osmosis system as a trial for reduction of heat treating time and quality drop in concentration of the juice. The permeate fluxes through CA 865 and CA 960 membranes were higher than those of HR 95 and HR 98 membranes even at the low operating pressure. In the concentration limit depended on the membranes used, HR membranes operated at 60 bar showed $29.0^{\circ}$Brix, and the time required to reach the limit was 86 min for HR 95 and 71 min for HR 98. In cases of CA membranes run at 30 bar, the juice concentration was linearly increased without the limit, and longer time to reach the same concentration was required in comparison with HR membranes. As the juice concentration was increased, the loss of soluble solids was increased, and the average contents of soluble solids in the permeate passed through HR 95, HR 98, CA 865 and CA 960 were 1.3, 0.5, 7.5 and $2.3^{\circ}$ Brix, respectively, in the juice concentration range of 20.0 -$25.0^{\circ}$ Brix. The lower amounts of sugars, total acid and flavor volatiles were involved in the permeate through HR membranes, especially HR 98 than in the permeate through CA membranes.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.1
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• pp.44-49
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• 2008

Sufficient inorganic nitrogen supply for crop growth is crucial for economically sustainable organic farming. The effects of an application of cover crop biomass on crop growth, nitrogen utilization and carbohydrate composition were investigated during early stage. Short-term changes in soil nitrogen after incorporating fresh hairy vetch and rye shoots were measured. The inorganic nitrogen from cover crops reached the peak at 15 ($NH_4-N$) and 24 ($NO_3-N$) days after incorporation, and then decreased rapidly. The highest concentration of soil nitrate showed at 27 days of incorporation in hairy vetch and at 18 days in rye, and three fold differences exhibited between two treatments. Crop growth under hairy vetch or rye incorporation significantly differed. At 20 DAT, dry matter production in NPK and hairy vetch was about two fold greater than that in rye. Difference in decomposing rates of hairy vetch and rye had also influence on nitrogen status in leaves and roots of pepper plants. Total nitrogen was greater in NPK and hairy vetch than in rye until 20 DAT, whereas inorganic nitrogen (nitrate and nitrite) concentration was higher in rye. Temporal changes in soluble sugars and starch in pepper plants among treatments were similar, although difference in the amount existed. It was suggested that hairy vetch as an alternative nitrogen source promoted crop growth and mineral utilization during early growth stage, whereas an obvious effect in rye was not found.

• Korean Journal of Medicinal Crop Science
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• v.6 no.4
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• pp.305-310
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• 1998

Glucosidic bond at the $C_{20}$ position of the sapogenins was hydrolyzed easily in the lower pH, higher temperature and longer time to give prosapogenins and sugars. The glucosidic bond of saponin at the $C_3\;of\; ginsenoside-Rb_1\;$, which is secondary carbon, was relatively stable due to the low electron density of -0.2. But the bond of saponin at the $C_{20}$ position, which is tertiary carbon with the relatively high electron density of -0.3, was liable to be hydrolyzed even in weak acidic solution by the increase of heating time. On the other hand, fresh and white ginseng contained 4.12 mg/g, 13.05 mg/g of citric acid, 0.68 mg/g, 2.18 mg/g of malonic acid, 1.13 mg/g, 3.68 mg/g of oxalic acid, 2.68 mg/g, 8.62 mg/g of malic acid and 0.13 mg/g, 0.46 mg/g of succinic acid, respectively. Ginseng saponins were very stable in ginseng extract neutralized with sodium carbonate or sodium bicarbonate corresponding to the equivalent amount of the total organic acid in the ginseng.

• Food Science of Animal Resources
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• v.28 no.2
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• pp.204-210
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• 2008

A total of 70 colonies were isolated from the Korean human milk samples on the BCP plate count agar. These LAB isolates were subcultured in 10% reconstituted skim milk, and two strain thereof were finally selected for their highest acid productions. These strains were identified as Enterococcusfaecium based on 16S rDNA sequencing data, named as Enterococcus faecium KHM-11. Sugar utilization of E. faecium KHM-11 was investigated by API 50CH kit, and 19 different sugars including D-arabinose, L-arabinose, galactose, D-glucose, D-fructose, and D-mannose were utilized. For fermentation profiles, a yogurt inoculated by E. faecium KHM-11 after 15 hour, reached at pH 4.09, titratable acidity at 1.10% and average viable counts $1.30{\times}10^9\;CFU/mL$. Effects of the administration of yogurt 0.5% of piglet diet to piglets were investigated for growth rate, analysis of blood and incidence of diarrhea. 24 heads of piglets were divided into two groups: the experimental and the control of 12 animals each. The average growth rate in the yogurt-fed group was higher for 21.67%, compared with control (p<0.05). There were no differences in the concentrations of blood glucose, cholesterol, albumin and globulin between the two treatments. Incidence of diarrhea was no in pigs fed yogurt as compare to control.

• Applied Biological Chemistry
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• v.44 no.1
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• pp.24-29
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• 2001

Extracts of Acanthopanax koreanum Nakai were decreased as the ethanol concentration was increased, but eleutherosides were increased. Extracts were increased as the extraction time was prolonged. Compared to 15 hrs extraction, extract yield and eleutherosides for 5 hrs extraction were 90.6% and 96%, respectively. Yields of extract and eleutherosides were 6.5% and 75% at $100^{\circ}C$. The optimum extraction conditions were obtained from the samples of 4 years' tree harvested at September, which were water and 50% ethanol as solvents, and $90^{\circ}C$ for 5 hrs extraction. Soluble solids, minerals, free sugars, free acids, free amino acids and total eleutherosides in the extract of Acanthopanax koreanum were $48.2{\sim}47.4%$, $4.5{\sim}5.3%$, 11.2711.80%, $3.02{\sim}3.18%$, 185.33 mg/100 $g{\sim}$ 348.14 mg/100 g and 990.84 mg/100 $g{\sim}$l,416.10 mg/100 g, respectively. The extract was viscous and yellowish brown liquid.

• The Korean Journal of Food And Nutrition
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• v.15 no.1
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• pp.42-50
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• 2002

This experiment was carried out to investigate the effect of Maesil extract on the acid production and growth of yoghurt starter in the skim milk medium. The Maesil extract was added to skim milk medium fur 1% to 9% and the medium was fermented by single or mixed culture of 4 types of lactic acid bacteria(Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus, bulgaricus, Lactobacillus casei). The chemical composition of Maesil, the changes in acid production (titratable acidity, pH) and number of viable cells of the medium during lactic fermentation in skim milk added with Maesil extract, and the keeping quality of curd yoghurts containing Maesil extract have determined. The composition of Maesil were 0.4% crude ash, 4.1% dietary fiber, 4.66%l citric acid, 0.264% total sugars and 405.34mg% vitamin C. The addition of Maesil extract stimulated the acid production and propagation of the lactic acid bacteria. Among the treatments tested, the addition of 3% Maesil extract with the mixed culture of Streptococcus thermophilus, Lactobacillus acidophilus and Lactobacillus casei produced the highest amount of acid(1.23%) and showed the highest number of viable cell counts(3.6$\times$10$^{11}$ cfu/mL). When the curd yoghurts containing 3% Maesil extract with the mixed culture of the lactic acid bacteria were kept at 4$^{\circ}C$ and 2$0^{\circ}C$ for 30 days, it was showed that the changes of titratable acidity, pH and number of viable cell counts of the lactic acid bacteria were not significantly different during storage. Therefore the keeping quality of the curd yoghurts adding 3% Maesil extract showed relatively good at the shelf-life.