• Korean Journal of Food Science and Technology
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• v.1 no.1
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• pp.51-61
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• 1969

In order to eliminate the considerable loss of rice by insects, to protect the human body from toxin excreted by some microbes, and to promote the storage efficiency of rice by employing the irradiation, the following experiments were carried out. Two varieties of rice, Paldal and Nongkwang polished and unpolished by the conventional methods and were packaged in polyethylene bags. After irradiating to the doses of 6-400 Krad of gamma-radiation from a $Co-^{60}$ source the samples were stored at the room temperature $20^{\circ}C$ for 8 months. The effects of radiation in terms of the removal of insects and microbes and the changes of chemical components (such as moisture, amylose, free sugar, and rancidity) were determined monthly from march to October during the storage. 1) Infestation of insects was greatly influeneed by the packaging materials used. There was no infestation in rice being packaged in a polyethylene bag, while as the rice packaged in a straw sack was infested in two months of the storage. 2) Some yeast and molds survived 400 K rad of radiation. Sterilizing dose to inhibit reproduction and growth of microbes was presumed to be higher than 400 K rad. Yeast mainly were found on the surface of rice, but mold were embeded into rice kernels by mycelium. 3) Changes of moisture contents during storage was not affected by radiation but was by humidity of the storage room. 4) Amylose content in starch increased with increasing dose of radiation and with the length of storage time, indicating possible depolymerization of starch molecules. 5) Free reducing sugar content was not affected by radiation and decreased with storage time. 6) Rancidity also increased with does and storage time.

• Food Science and Preservation
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• v.24 no.4
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• pp.497-504
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• 2017

The aim of this study was to investigate the characteristics of paprika dried by various methods. Moisture content of dried paprika was higher in vacuum freeze-dried red paprika (DRP) (11.85%) than in vacuum freeze-drying of osmotic dried red paprika in sugar (RPS), vacuum freeze-drying of osmotic dried red paprika in fructose (RPF) and vacuum freeze-drying of osmotic dried red paprika in corn syrup (RPCS). Carbohydrate content of DRP was the lowest among the dried groups, but fat, protein, and ash contents were the highest in DRP. The pH of paprika was the highest in RPF (5.34), while it was the lowest in DRP (5.05). Reducing sugar and sugar contents of RPF were 28.59 g/100 g and $5.03^{\circ}Brix$, respectively, which are the highest level among the groups. All color values in inside of paprika were the highest in RPCS, while in outside of paprika, L value is the highest in RPCS, and the value of a, b were the highest in RPS. Regarding the texture characteristics of paprika, strongness, hardness, adhesiveness, chewiness and brittleness were the highest in RPS (p<0.05).

• Journal of the East Asian Society of Dietary Life
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• v.27 no.1
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• pp.1-8
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• 2017

This study was conducted to investigate alterations of seaweed composition upon Lactobacillus rhamnosus GG (LGG) fermentation as well as potential anti-inflammatory effects and mechanism (s) of water extracts and fermented water extracts of Laminaria japonica (LJ) and Hizikia fusiforme (HF) in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Total polyphenol, total sugar, and reducing sugar contents were measured in LJ and HF water extracts before and after fermentation by LGG. Alterations of inflammatory cytokine levels in cell culture media were measured by ELISA, and levels of phosphorylation of c-jun NH2-terminalkinase (JNK) and extra cellular signal regulated kinase (ERK) were examined by Western blot analysis. LGG fermentation of LJ and HF altered total polyphenol and sugar contents in water extracts of LJ and HF. LPS-induced production of pro-inflammatory cytokines such as IL-6 and $TNF-{\alpha}$ was significantly reduced by HF-f compared to control in RAW264.7 cells. Consistent with reduction of anti-inflammatory cytokine, interleukin (IL)-6, and tumor necrosis factor $(TNF)-{\alpha}$ levels by HF-f, HF-f also significantly reduced phosphorylation of ERK and JNK in LPS-stimulated RAW264.7 cells. In addition, LJ-f and HF also significantly reduced phosphorylation of JNK and ERK induced by LPS in RAW264.7 cells. Overall, our result suggests that HF-f among the four tested seaweed extracts is the most potent anti-inflammatory agent, and its mechanism of action is partially mediated by reduction of JNK and ERK phosphorylation as well as IL-6 and $TNF-{\alpha}$ production in LPS-stimulated RAW264.7 cells.

• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.326-330
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• 1985

To measure the optimum reconditioning period, potatoes stored at low temperatures ($0^{\circ}C$, $5^{\circ}C$ and $10^{\circ}C$) for three months were reconditioned at $20^{\circ}C$. Contents of glucose, fructose and sucrose of halved and whole potatoes were monitored during the course of storage and reconditioning. In halved potaotes basal portion contained higher amount of glucose, fructose and sucrose. The sugars in basal portion decreased more rapidly than those in apical portion, and sucrose disappeared fastest among the sugars in both portions during reconditioning period. The relationship between reducing sugar and reconditioning period could be presented as exponential equation. I consideration of uneven distribution of sugar contents between apical and basal portion, the required optimum reconditioning period at 20 could be 1.3 weeks, 5.6 weeks and 9.4 weeks for potatoes stored at $10^{\circ}C$, $5^{\circ}C$ and $0^{\circ}C$, respectivery.

• Journal of the Korean Society of Food Culture
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• v.4 no.4
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• pp.411-416
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• 1989

Optimum leaching conditions of Korean green tea were determined by examining the relationship between sensory evaluation and tasting constituents of green tea infusion at various leaching conditions. Total nitrogen, total reducing sugar and tannin contents of green tea were $4.70{\sim}5.02%$, $16.5{\sim}18.0%$ and $10.3{\sim}12.7%$, respectively. They increased with the increased of leaching temperature and time. The sensory score was significantly correlated with the tannin contents of green tea in fusion in the range of $15{\sim}30\;mg/g$.(r=-0.9061). Optimum leaching conditions of green tea were $0.5{\sim}1.0$ min at $55^{\circ}C$, 0.5 min at $70{\sim}85^{\circ}C$ in high grade parched green tea, $1.0{\sim}2.0$ min at $55^{\circ}C$ and $0.5{\sim}1.0$ min at $70^{\circ}C$ in medium one.

• Journal of the Korean Society of Food Culture
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• v.11 no.3
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• pp.339-348
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• 1996

Physicochemical and sensory characteristics of Korean traditional alcoholic beverages, such as Kwahaju, Sokokju, Baikhaju, Samhaeju and Hosanchun were investigated during fermentation with the difference of input step and treatment of rice and Nuruk (Korean-style bran koji). pH values in all treatments were similar to be ranged $3.1{\sim}3.2$, but acidity of the treatment brewed without seed mash was $1.5{\sim}2$ times higher than that of the treatment brewed with seed mash. The concentration of alcohol in all treatments increased as the concentration of the Nuruk increased. The alcohol concentrations of Samhaeju and Hosanchun ranging from 6.5% to 7.7% were higher than those of Kwahaju, Sokokju and Baikhaju ranging from 7.9% to 10.6%. Residual reducing sugar contents of Kwahaju, Sokokju and Baikhaju ranging from 4.6 g/L to 9.7 g/L were lower than those of Samhaeju and Hosanchun ranging from 14.2 g/L to 15.5 g/L. The consumed total sugar contents of Kwahaju, Sokokju and Baikhaju ranging from 125.4 g/L to 159.2 g/L were higher than those of Samhaeju and Hosanchun ranging from 111.2 g/L to 123.8 g/L, and the treatments brewed with seed mash showed more sugar consumption than the treatments brewed without seed mash. Sensory quality in the treatments brewed with seed mash was better than those of without seed mash. Concentration of Nuruk and preparation of seed mash from it were critical factors compared to input step and treatment of rice in Korean traditional alcoholic beverage brewing.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.75-81
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• 2010

In order to investigate the effects of different milling degrees on the quality of glutinous rice wines, the physicochemical properties and volatile compounds of various wines were evaluated. Sample wines prepared from glutinous rice with 90, 80, and 70% milling yields were analyzed for ethanol, pH, total acids, amino acids, soluble solids, coloring degree, UV absorbance, reducing sugars, organic acids, free sugars and volatile compounds. After fermentation for 17 days, ethanol contents in the wines ranged from 15.2 to 15.85%, while total acid levels ranged from 0.31 to 0.35%. The amino acid contents in four samples ranged from 0.63 to 0.73%, while soluble solid contents ranged from 11.4 to $13.1^{\circ}Bx$. The wine prepared from glutinous rice with a 30% degree of milling showed the highest coloring degree, UV absorbance and reducing sugar content among four samples. Furthermore, this wine had the highest levels of malic acid and acetic acid, while the glutinous rice wine prepared from rice with a 0% degree of milling had the highest levels of succinic acid and lactic acid. In all the glutinous rice wines tested, the most abundant free sugar was glucose followed by maltose. With increasing degree of milling, the alcohol, amino acid and organic acid contents of the glutinous rice wines decreased, whereas soluble solids, coloring degree, UV absorbance, reducing sugar and free sugar contents increased. Volatile compounds were identified using GC-MSD, and thirty-nine esters, seven alcohols, six acids, one aldehyde, four alkanes, one alkene and two miscellaneous compounds were identified in the glutinous rice wines. Using relative peak area, it was determined that other than ethyl alcohol, hexadecanoic acid ethyl ester was the major component and was primarily found in the range of 11.566-18.437%. Succinic acid diethyl ester and isoamyl laurate decreased with an increasing degree of milling, whereas hexanoic acid ethyl ester and 2-octenoic acid ethyl ester increased. Overall, it was shown that different milling degrees greatly affected the physicochemical and volatile characteristics of the glutinous rice wines.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1038-1040
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• 2001

This study was conducted to investigate the constituents of pumpkin, to develop of health food using pumpkin. Crude protein contents of skin (19.82%) and fiber (16.43%) were higher than that of flesh. Crude lipids contents of skin (2.84% ) was higher than those of flesh and fiber. Major free sugars in pumpkin were sucrose, fructose and glucose. Total sugar contents in the flesh was higher than that of fiber. This tendency was opposite to reducing sugar contents. Also, free sugar contents in pumpkin were flesh (30.19 mg/100 g), fiber (22.99 mg/100 g) and skin (15.67 mg/100 g), respectively. The total Phenol and carotenoid contents in 100 g of fiber revealed 379.8$\pm$9.76 mg and 43.71$\pm$1.46 mg, corresponding to 47% and 62% of the total phenol and carotenoid contents of pumpkin. Total flavonoid content in 100 g of skin revealed 81.5$\pm$3.56 mg.

• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.266-271
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• 1992

The contents of capsaicinoids, free sugars and organic acids of 10 Korean varieties of red pepper power were measured and the sensory properties of their water extracts were compared in order to investigate the influence of the composition of taste components on sensory acceptability of Korean red pepper. The composition of taste components in red pepper powder varied widely depending on the varieties; total capsaicinoid content varied from 0.029 to 0.296%, free sugar $8.45{\sim}15.21%$ and organic acid $4.58{\sim}17.54%$. Capsaicinoid contents, especially dihydrocapsaicin content, were highly correlated with the pungent taste of the water extract of red pepper powder (r=0.870), but did not show significant relationship to the overall sensory acceptability. The sensory overall acceptability was highly influenced by the contents of total sugar (r=+0.815), reducing sugar (r=+0.805), glucose (r=+0.814) and fructose (r=+0.787). Multiple regression with total sugar $(X_1)$, total capsaicin $(X_2)$ and total organic acid contents $(X_3)$ increased the correlation coefficient for sensory acceptability(Y) to R=0.9008. From the result, a regression equation of $Y=0.9808X_1-10.7526X_2-0.1664X_3-4.1147$ was obtained.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.1
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• pp.48-52
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• 1993

To furnish basic data for the utilization of leaf mustard as a raw material of salted and fermented vegetable food, major chemical compositions of Dolsan Leaf Mustard (DLM) were investigated. The moisture and ash contents of DLM were 87.5% and 1.4%, respectively. Compared with other Korean traditional or Japanese leaf mustard, DIM contained more crude protein (3.8%) but less crude fat (0.3%) and crude fiber (1.3%). As an alkali food, leaf and leat stalk had pH of 5.7 and 5.8, titratable acidity of 687 and 318mg/100g and alkalinity of 2.5 and 5.2, respectively. The major free sugar in DLM was glucose and fructose was also detected in a small amount. The contents of total and reducing sugar in leaf and leaf stalk were 574, 352, 820 and 538mg%, respectively. Total amino acid contents of leaf and leaf stalk were 8.0 and 2.5% on wet basis. Although the amino acid compositions of leaf and leaf stalk were different each other, glutamic acid and proline were the major amino acids in both of the leaf and leaf stalk. Significantly higher amount (ca.10.3-fold) of free amino acid was present in leaf (3074mg%) than in leaf stalk (298mg%). Glutamic acid and aspartic acid were the major free amino acids and essential amino acid contents in leaf and leaf stalk were 869 and 68mg% being 22.9 and 28.3% of total free amino acids.