• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.11
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• pp.1575-1581
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• 2011

Rapeseed cake, which is the organic waste remaining after rapeseed oil production, is readily available and considered an ecologically-friendly resource with very low cost and high dietary fiber content. This research was carried out for two reasons. First, it was done to analyze the liberated reducing sugar content of rapeseed cake. Second, it was done to investigate the effects on the sugar yield of the various concentrations of acidic and alkaline catalysts used for the hydrolysis of rapeseed cake and the concentrations of rapeseed cake in each catalyst. Several amounts of ground rapeseed cake, 0.5 g, 1 g, and 2 g, were put into 100 mL of catalysts such as sulfuric acid (0.5~2%), hydrochloric acid (0.5~2%), and sodium hydroxide (0.5~2%). Then they were hydrolyzed for 5 min at 121$^{\circ}C$. After hydrolysis, HPLC equipped with an RI detector was used to analyze liberated reducing sugars such as sucrose, glucose, galactose, fructose, and arabinose separated from rapeseed cake. The degradation rate of rapeseed cake was the highest in hydrochloric acid. As the catalyst concentrations used for hydrolysis of rapeseed cake increased, the degradation rate of rapeseed cake also significantly increased. Total reducing sugar content was the highest in hydrochloric acid, and it increased with the increase of catalyst concentrations. However, as the amount of rapeseed cake increased, the total reducing sugar content decreased, exceptionally sucrose in the case of sodium hydroxide.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.777-784
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• 2016

This study aimed to evaluate the quality characteristics of wheat-Makgeolli (WM), a traditional Korean cereal alcoholic drink, using three varieties of wheat, namely Jokyoung (JK), Baegjoong (BJ) and Keumkang (KK). Samples of WM brewed from 100%, 85% and 70% milling rates of the three Korean wheat cultivars were analyzed for alcohol, pH, coloring degree, total acids, soluble solid, free sugars, and organic acids. As the milling rates in wheat decreased, total sugar content in WM increased while the pH of all samples decreased. The WM exhibited 0.95~1.27% in acidity, $10.2{\sim}12.5^{\circ}Brix$ in total sugar, and 14~16% in alcohol content. The most organic acids in WM was lactic acid, ranging in all the samples from 85.3~650.3 mg%. The results showed that BJ under a 70% milling rate had the highest reducing sugar contents and 15.97% in alcohol content. The carbohydrate content increased with the milling rate of wheat. Resulting in a positive correlation between carbohydrate content of wheat and total acids, reducing sugars (p<0.001), and alcohol content (p<0.05) in WM. Total sugar content is positively correlated with alcohol and reducing sugar content (p<0.001). Considering the yield, the milling rates will be adjusted to raw material prices.

• Korean journal of food and cookery science
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• v.30 no.6
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• pp.746-756
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• 2014

This study investigated the quality characteristics and physiological activities of takju prepared with whole chestnut (15%, 30% and 50% with steamed rice) during fermentation. The pH level began to decrease after the secondary brewing stage. The total acid as well as the organic acid content increased during fermentation. Lactic acid and succinic acid were the main organic acids in takju fermented with whole chestnut. The level of total sugar and reducing sugars in takju fermented with whole chestnut increased at the first brewing stage and then slowly decreased after 4 days of fermentation. Also, the total number of viable cells and microbial populations such as lactic acid bacteria and yeast in the treatments increased to about 108 CFU/mL after 1 days of fermentation and then decreased gradually afterward. The ethanol content in takju fermented with whole chestnut rapidly increased during the initial 4 days of fermentation, to a maximum content of 18.2% after 8 days. The colour values of the treatments did not show any significant differences between 0% and 15% chestnut content. However L value decreased, while the a and b values increased when the whole chestnut content above 30%. The total polyphenol level, electron donating ability, nitrite-scavenging ability and ferrous ion effect also increased as the ratio of whole chestnut increased. Sensory scores of takju fermented with 15% chestnut were greater than those of takju prepared by other treatments.

• Korean journal of food and cookery science
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• v.20 no.6 s.84
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• pp.598-606
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• 2004

The application of Dongchimi liquid to Naengmyon broth to improve its eating quality was scientifically explored by reviewing the quality of the product properties. Primarily, the optimum fermentation conditions for Dongchimi from which the liquid portion was extracted were pursued and the optimum mixing ratio sought on the basis of the product physicochemical properties. The liquid portions, periodically extracted from Dongchimi at intervals of two or five days, during fermentation at $10^{\circ}C$, were added to Naengmyon broth. The treatments were prepared at three levels namely, basic broth only ('A') and with ratios of Dongchimi liquid to basic broth of 3:7 (v/v, 'B') and 5:5 (vfv, 'C'). As a typical phenomenon of kimchi fermentation, a gradual decrease in the pH with increasing total acidity was observed as the fermentation of the Dongchimi progressed. At $10^{\circ}C$, the optimum ripening was obtained from day 8, and continued until day 15, when the pH was maintained at about 3.8 to 4.0. The total vitamin C and reducing sugar contents increased until the 13th-day of fermentation, but then decreased thereafter. The turbidity and solid content of the Dongchimi liquid increased with progression of the fermentation. With respect to the color values, the lightness (L) decreased, with increases in the redness (a), yellowness (b) and total color difference $({\Delta}E)$ during fermentation. Most of these observed phenomena for the Naengmyon broth substituted with $30\%$ (Treatment 'A') and $50\%$ (Treatment 'B') Dongchimi liquid, with different storage periods, confirmed the previous fermentation patterns of Dongchimi. A decrease in the pH with increasing total acidity, as well as gradual increases in the total vitamin C and reducing sugars (glucose and fructose) up to the 13th-day of fermentation were accompanied by subsequent declining patterns. The turbidity and solid content of the mixed broth also increased with increasing Dongchimi liquid fermentation period. With respect to the color of the mixed broth, the lightness was decreased, while the redness, yellowness and total color difference increased with increasing Dongchimi liquid fermentation period. It was also proven that the addition of slightly over-ripened Dongchimi liquid to the Naengmyon broth was more preferable.

• Korean Journal of Food Science and Technology
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• v.5 no.3
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• pp.183-187
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• 1973

Soong-Neung is a Korean traditional beverage served after meals and is made from Soong-Neung producing rice (Noo-Roon-Bap) which is cooked and toasted rice produced on the bottom of the container during the rice cooking process. In order to study the chemical changes occurring in Soong-Neung producing rice with temperature$(20{\sim}220^{\circ}C)$ during the cooking process, thermal analysis, total sugars, total nitrogen, reducing sugars, water soluble nitrogen, total acid, carbonyl content, phenolic compounds were determined. Thermal analysis showed that decrease of weight and endothermic reaction caused by evaporation of water in the sample appeared at $95{\sim}130^{\circ}C.$ The production of volatile compounds increased gradually beginning at $130^{\circ}C$, however, those compounds increased markedly at $160^{\circ}C$ and above. Maximum absorption of ultraviolet spectra of an aqueous distillate occurred at about $273m{\mu}$. Organoleptic analysis showed that an acceptable flavor was produced in the temperature range of $125{\sim}155^{\circ}C.$

• Food Science and Preservation
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• v.10 no.3
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• pp.333-338
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• 2003

pH values in all samples were in the range of 5.04 to 5.32. pH of kanjang prepared with normal pressure(NPK) was higher than that of kanjang prepared with high pressure(HPK) and kanjang prepared with steam(SPK). Titratable acidity(TA) in all samples were found to be 4.26～7.72 mL. TA in HPK(5.99～6.96 mL) was lower than that in SPK(4.26～5.61 mL) and NPK(7.32 mL). Reducing sugar(RS) contents in all samples were in the range of 25.18 to 194.81 mg％. RS contents of HPK and SPK were a similar pattern and were higher than that of NPK. Major free sugars(FS) were glucose, fructose and xylose. In total FS, SPK was higher than that of NPK and HPK. Major organic acids(OA) were succinic acid, oxalic acid, tartaric acid, malic acid and citric acid. In total OA contents, SPK(40.38～76.96 mg％) was higher than that of NPK(55.85 mg％)and HPK(27.78～34.21mg％). OA contents in HPK and SPK were decreased slightly according to the heating time of whole black bean. The highest percentage of fatty acid (FA) in all samples was palmitic acid(33.28～43.51 ％ as area ％ of GC chromatogram), followed in a decreasing order by stearic acid(14.15～19.16％) and myristic acid(5.93～19.14％). The composition ratios of three FA to total FA ranged from 55.97 to 72.85＆. In all samples, there was myristic acid that was not contained in raw soybean.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.828-832
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• 1990

Pileus and stipe extracts of shiitake mushroom were prepared with various ethanol concentration by different extraction time at $60^{\circ}C$. Yields, total reducing sugars, free amino acids and nucleotides in ultrafiltrated extracts were analyzed. Yields were higher in hot water extracts but there was no difference depending on changes of extraction time. Total reducing sugar contents got higher by hot water extraction than by solvent extraction. In hot water extracts of the pileus and stipe, reducing sugar content were in the range of $416.18{\sim}488.18\;mg%\;and\;435.37{\sim}452.12\;mg%$, respectively. Threonine+serine, glutamic acid, lysine and arginine were dominent in the free amino acids pool of raw material. The contents of free amino acids in hot water extracts of pileus and stipe were about 528.46mg% in 2 hr and 221.01 mg% in 3 hr. The proportion of bitter amino acids in extracts to total free amino acid contents was in the range of $16{\sim}29%,\;35{\sim}37%$ in pileus and stipe extracts, respectively. Nucleotides contents were higher in pileus than in the stipe. When the 25% ethanol solution was used for extraction solvent, nucleotides contents in pileus and stipe extracts was high.

• Food Science and Preservation
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• v.15 no.2
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• pp.185-190
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• 2008

We investigated changes in fruit quality of Hallabong tangor (Citrus Kiyomi ${\times}$ ponkan) that was packaged with Si+CaO and LDPE film. The flesh ratio during storage was 74.33% (${\pm}3.66$) to 81.56% (${\pm}1.38$). Firmness of M16A, a variant of Hallabong tangor, was higher 100g-force than that of Hallabong tangor, changes of firmness was not shown among film packages. A fruit juice was $12-14^{\circ}$Brix, and this increased somewhat at the end of storage without film packaging. The titratable acidity of the M16A variety was 0.2% lower than that of the Hallabong tangor. Hallabong and M16A maintained freshness and taste for 120 and 60 days, respectively. The level of reducing sugars in the Hallabong tangor was 1% higher than that of the M16A variety. Reducing sugars increased at room temperature storage without film packaging. Total sugar content was 9.19% (${\pm}2.03$) to 12.78% (${\pm}0.75$). The content of vitamin C declined slowly after 105 days of storage. In conclusion, storage of Hallabong tangor with film packaging coated with Si+CaO was effective for maintaining freshness and quality.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.59-59
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• 2018

Panax ginseng Meyer (Korean ginseng) is in the spotlight of Oriental medicine and is proclaimed as the king of medicinal plants owing to its adaptogenic characteristics. Ginseng root rot is a devastating disease caused by the fungus, Ilyonectria mors-panacis that generally attacks younger roots (~2 years), leading to defects in root quality, ginsenoside accumulation and also life cycle of the plant. Hence, there is an indispensable need to develop strategies resulting in tolerance against ginseng root rot. In the present study, we evaluated the effect of silica nanoparticles(N-SiO2) in Panax ginseng during I. mors-panacis infection. Long term analysis (30 dpi) revealed a striking 50% reduction in disease severity index upon 1mM and 2mM treatment of N-SiO2. However, N-SiO2 did not have any direct antifungal activity against I. mors-panacis. Membrane bound sugar efflux transporter, SWEET (Sugars Will Eventually be Exported Transporters) was identified in ginseng and as expected, its expression was suppressed upon N-SiO2 treatment in the root rot pathosystem. Furthermore, the total and reducing sugars in the apoplastic fluid clearly revealed that N-SiO2 regulates sugar efflux into apoplast. In a nut shell, N-SiO2 administration induces transcriptional reprogramming in ginseng roots, leading to regulated sugar efflux into apoplast resulting in enhanced tolerance against I. mors-panacis.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.109-114
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• 2011

In this study, we investigated the feasibility of producing bioethanol from the hydrolysate of rape stem. Specifically, the most ideal yeast strain was screened, and the microaeration was performed by surface aeration on a liquid medium surface. Among the yeast strains examined, Pichia stipitis CBS 7126 displayed the best performance in bioethanol production during the surface-aerated fermentor culture. Pichia stipitis CBS 7126 produced maximally 9.56 g/l of bioethanol from the initial total reducing sugars (about 28 g/l). The bioethanol yield was 0.397 (by the DNS method). Furthermore, this controlled surface aeration method holds promise for use in the bioethanol production from the xylose-containing lignocellulosic hydrolysate of biomass.