• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.442-447
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• 1994

Effect of different mixing ratio of non-glutinous and glutinous rice on physical and rheological properties of extrudate prepared in a single screw extruder were examined. The extrusion conditions in term of screw speeds, moisture content and die temperature were 258 rpm, 18% and $120^{\circ}C$, respectively. The resisdence time distribution of the most of materials were within 30 second and small portion of them went up to 80 second. The expansion ratio was the highest value (2.93) for 70% of glutinous rice in the mixture, while the lowest value for 100% of non-glutinous rice. Breaking strength was in the range between 1,051g and 1,117g for $10{\sim}20%$ of glutinous rice in the mixture, while the lowest value (737g) for 80%r of glutinous rice. As the amount of glutinous rice increased, L and a values were increased and b value was decreased. The uncooked cold paste viscosity had 400 B.U. for 100% non-glutinous rice , while no peak for the 100% glutinous rice. As the amount of glutinous rice increased up to 100%, the water absorption index (WAI) was decreased, while water solubility index (WSI) was increased. The rheological properties of extrudate were accounted by the law of Oswald. The flow behavior index of extrudate was less than 1.0, which showed pseudoplastic behavior. Yield stress was the highest value for 20% of glutinous rice in the mixture and the lowest value for $80{\sim}100%$ of glutinous; rice. Number of air cell was between 128 and 159 for $80{\sim}100%$ of glutinous rice in the mixture, while $81{\sim}84%$ for $0{\sim}20%$ of glutinous rice. The degree of shapefact was increased more when the mixtures of glutinous and non-glutinous rice was used than when glutinous or non-glutinous rice was only used.

• Culinary science and hospitality research
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• v.22 no.3
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• pp.55-65
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• 2016

The purpose of this study was to determine the most appropriate ratio for burdock glutinous rice Dasik. Burdock glutinous rice Dasik was prepared with different levels of burdock powder (0, 3, 6, 9 and 12%) and the quality characteristics of burdock glutinous rice Dasik were analyzed. Moisture contents of burdock glutinous rice Dasik increased as the amount of burdock powder increased (p<0.001) compared to the control group. The L-value, a-value, and b-value of burdock glutinous rice Dasik showed a tendency to decrease compared to the control group. The sugar content of burdock glutinous rice Dasik increased (p<0.001) with the amount of burdock powder. The hardness and adhesiveness of the glutinous rice Dasik with burdock powder of 6% or less were decreased, but those with 9% or more burdock powder had higher hardness and adhesiveness than the control group. In addition, the cohesiveness, springiness, gumminess, and chewiness of glutinous rice Dasik with burdock powder increased compared to the control group. The DPPH free radical scavenging activity of the glutinous rice Dasik with 9% and 12% burdock powder were higher than that of the control group (p<0.001). In the sensory test of burdock glutinous rice Dasik, the samples added with 3% and 6% burdock powder gained higher preferences, but the evaluations of others were lower than that of the control group. The glutinous rice Dasik with less than 6% burdock powder was highly evaluated, so it is considered as the most appropriate sample.

• Food Science and Preservation
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• v.16 no.2
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• pp.266-275
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• 2009

To develop new high-quality Yakchobugak, features of Lactococcus lactis-fermented waxy rice paste after addition of some colored powdered agro-food products were investigated. Total and reducing sugars of waxy rice paste fermented by lactic acid bacteria were higher than those of control raw waxy rice paste. Total acidity gradually increased as powder concentration rose, being 1.02-1.56% and 0.96-1.87% in samples fermented with Cucurbita maxima and Capsicum annuum powders, respectively; these values were 3-4 times those in rice fermented with other powders. Fermented waxy rice paste viscosities were lower than those of non-fermented samples. The viscosities of samples fermented with Curcuma longa and Opuntia ficus powders were in the range $100-160{\times}10^4$ centipoise($mPa{\cdot}s$), and those of pastes fermented with Robus coreanus and Camellia sinensis extracts were under $40{\times}10^4mPa{\cdot}s$. Hunter color lightness(L) values decreased and yellowness(b) values rose after fermentation. Waxy rice paste fermented with Robus coreanus showed uniform particle size distribution, and many pores, by scanning electron micrography.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.612-618
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• 1999

Physicochemical properties of amaranth starch were compared with those of waxy rice and waxy corn starches. Amaranth starch granules vary from $1.1{\sim}1.9\;{\mu}m$ in diameter and are polygonal in shape. Total amylose contents from waxy rice, waxy corn and amaranth starches were 0.01, 0.03 and 0.07%, respectively. Swelling power of amaranth starch granule was slightly different from waxy rice. The swelling power of amaranth increased at $70^{\circ}C$. X-ray diffraction patterns of amaranth and other waxy cereal starches showed an A-type crystalline structure. Relative crystallinities of their starches were similar. According to pasting properties by Rapid Visco-Analyzer, amaranth starch showed a very high gelatinization temperature $(75.1^{\circ}C)$ and lower viscosity and higher stability than other waxy cereal starches during heating and cooling cycle. Peak onset temperatures (To) of starches from waxy rice, waxy corn and amaranth in DSC thermograms were $58.7{\sim}64.0$, 67.2 and $71.5^{\circ}C$, respectively, and their peak enthalpies were similar. Enthalpy of reheated amaranth starch after 3 day storage at $4^{\circ}C$ was higher than those of waxy corn and rices starchs.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.638-643
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• 1998

The volatile flavor components in Takju made from mashed glutinous rice and barley rice were identified by GC and GC-MS using polar column. Twenty eight kinds of flavor compounds including 10 alcohols, 9 esters, 2 acids, 7 aldehydes were identified. At the beginning of fermentation 14 kinds of volatile components were detected and the kinds of volatile components were increased up to maximum after fermentation for 16 days. The contents of volatile components in the sample made from glutinous rice contained slightly higher than the sample made from barley rice. Ethyl alcohol, n-propyl alcohol, iso-amyl alcohol, n-hexyl alcohol, hexenyl alcohol, 2-phenylethyl alcohol, ethyl acetate, ethyl succinate, 2-phenylethyl acetate, butyic acid, benzaldehyde and 3-methoxybenzaldehyde were detected in the both of the sample throughout the fermentation process. Five kinds of aldehyde including ethyl propionate, iso-amyl acetate, ethyl caprylate and ethylphenyl acetate were detected only in the sample fermented for 16 days. The main components of the both sample were ethyl alcohol, iso-amyl alcohol, 2-phenylethyl alcohol, 2-phenylethyl acetate, hexenyl alcohol and iso-butyl alcohol. Besides ethyl acetate and benzaldehyde from glutinous rice Takju and hexenyl alcohol from barley rice Takju were found as main components.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.10
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• pp.1353-1361
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• 2009

This study investigated the effect of waxy barley on the incorporation trans fat (tFA) into plasma lipid and lipid profile through 6 weeks trial. 39 healthy volunteers were divided into 2 groups and fed waxy barley bread (WBG) or wheat bread (WG) containing equivalent amounts of tFA (elaidic acid rich, 3.75 g/day), respectively. Plasma lipid profiles and fatty acid composition at 0, 2, 4, 6 weeks after a respective bread were studied. Plasma lipid was extracted by the method of Folch, esterified by acid transmethylation and analyzed by gas chromatography. The fatty acid composition reflected the fatty acid proportion of the test fat. However, consumption of waxy barley bread with tFA for 6 weeks affected plasma fatty acid composition including tFA. Incorporation of tFA into plasma lipid was significantly lowered compared to WBG than in WG after 6 weeks of consumption. Furthermore, saturated fatty acids such as C16:0 and C18:0 levels were also significantly lowered in WBG than in WG. Furthermore, plasma total cholesterol level and TG/HDL-cholesterol ratio were also significantly lowered in WBG compared to WG at 2, 4 and 6 weeks. These results suggest that waxy barley bread with high $\beta$-glucan lowered plasma trans, saturated fatty acid and total cholesterol levels though the inhibition of lipid absorption.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.2
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• pp.96-104
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• 2017

This study was carried out to compare the cooking and antioxidant characteristics of rice containing varying amounts of glutinous rice and cooked by two methods. Rice containing glutinous rice was cooked by general and high-pressure cooking methods with and without fermented alcohol. Pasting characteristics of cooked rice were decreased with increasing amounts of glutinous rice. The water binding capacity and swelling power were significantly decreased with increasing amounts of glutinous rice; however, water solubility indices were significantly increased. Palatability characteristics of cooked rice containing glutinous rice were similar to those of cooked rice without glutinous rice. Total polyphenol contents of cooked rice containing glutinous rice and fermented alcohol were quite different, but this difference was not significant. Total flavonoid contents were increased with increasing amounts of glutinous rice. Total flavonoid content by general cooking method for rice containing 20% glutinous rice and fermented alcohol was $23.20{\pm}0.61{\mu}g\;CE/g$. DPPH radical-scavenging activities for samples with and without glutinous rice were 2.97-5.19 and 3.19-5.45 mg TE/100 g, respectively. ABTS radical-scavenging activity by high-pressure cooking method for rice containing 20% glutinous rice and fermented alcohol was $19.48{\pm}0.63mg\;TE/100g$. In this study, cooking and antioxidant characteristics of cooked rice containing glutinous rice generated data useful for manufacturing processed products.

• Korean journal of food and cookery science
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• v.2 no.2
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• pp.43-54
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• 1986

Back-pyun is a kind of rice cake made by steaming rice flour added sugar, water and salt and garnished with shredded chestnuts, dates, mushrooms and pinenuts. The Back-pyun has been widely used in Korean celebrations. This study aimed to compare and determine the effects on sensory characteristics and texture of Back-pyun 1) when the proportion of glutinous rice, added i.1 making Back-pyun, is 0%, 5%, 10%, 15%, 20%, 25% and 30% 2) then it reheated after storage for 0,24, 48 and 72 hours. Evaluation was conducted through sensory evaluation and objective evaluation. The results are as follows : 1. In sensory evaluation, color of Back-pyun turned yellow as the addition level of glutinous rice increased and then by reheating after storage for 24, 48 and 73 hours. Coarseness was not significantly different as the addition level of glutinous rice increased before storage. But Back-pyun reheated after storage for 24,48 and 72 hours were significantly different by the addition level of glutinous rice. Softness, dryness and crumblyness tended to decrease as the addition level of glutinous rice increased and by reheating after storage for 24, 48 and 72 hours. The most favorite tendency on the appearance was at the addition level of glutinous rice of 5%. Texture and overall preference were better at the addition level from 10% to 20% than any other levels. 2. Rheometer measurement indicated that compression force, gumminess ana chewiness tended to increase as the addition level of glutinous rice increased and decrease by the storage conditions. But work ratio and recovered height did not have much effect the addition level of glutinous rice and the storage conditions. Compression force of Back-pyun (not reheated) tended to increase by the storage time and the addition level of glutious rice. Especially it showed remakably increasing tendency during 24 hours storage (at $4^{\circ}C$) 3. Moisture content tended to increase by the addition level of glutinous rice and decrease by the storage time. But moisture content of Back-pyun reheated after storage for 24 hours stowed the increasing tendency. 4. Softness of Back-pyun had significant relationship with compression force and work ratio. Dryness and crumblyness had significant relationship with work ratio. Therefore compression force and work ratio represented the texture of Back-pyun.

• Korean Journal of Food Science and Technology
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• v.41 no.6
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• pp.644-651
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• 2009

This study was conducted to investigate the effects of steeping periods and temperatures of waxy rice on the microflora and enzyme activities of steeping water and waxy rice, as well as on the microscopic structures of waxy rice during the preparation of gangjung. When the steeping water was 15 and $35^{\circ}C$, yeast and lactic acid bacteria were the major microflora after 1 day. After 11 days, Lactobacillus spp. were the major bacteria, while Bacillus spp. were the primary microflora after 21 days. At $25^{\circ}C$ the primary species were Bacillus spp., Leuconostoc spp., and Bacillus spp. after 1, 11 and 21 days, respectively. The $\alpha$-amylase activity of steeping water increased proportionally with the increase of temperature and period, while the protease activity tended to increase for 11 days, but decreased at 21 days. The enzyme activities of the steeped waxy rice, especially the $\alpha$-amylase activity, decreased with higher steeping temperature, while the $\beta$-amylase and glucoamylase activity remained constant for up to 21 days. Observation using scanning electron microscopy indicated that intracellular cleavage of steeped waxy rice endosperm resulted in a rough surface morphology due to the exposure of polygonal starch granules. Tiny pinholes on the surface of waxy rice starch granules were also observed after steeping for 11 days.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.546-551
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• 2007

The physicochemical characteristics and sensory properties of Jinyangju were investigated at different degrees of milling (DOM; 0, 5, 7, and 10%) of waxy glutinous rice after 2 weeks of fermentation. The final pH values were 3.50, 3.84, 4.16, and 4.21 at the DOMs of 0, 5, 7, and 10%, respectively. The final total acidities were 1.21, 1.16, 0.94, and 0.91%; final total sugar contents were 6.38, 6.51, 5.54 and 5.40%; and final alcohol contents were 14.50, 14.50, 15.50, and 15.40%, respectively. Hunter L-value of the DOM 5% rice was lower those of the DOM 7% and 10% rice, but its Hunter b-value was higher than those of the DOM 7% and 10% rice. However, Hunter a-value of the Jinyangju were not significantly different among the samples (p>0.05) Hunter L-value. The Jinyangju made with the DOM 7% rice showed the highest overall sensory preference.