• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.12-16
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• 2002

In this study, the physicochemical properties of warty black and glutinous rice flours were compared. Crude protein content of waxy black rice flour (9.01%) was higher than than of glutinous rice flour (7.54%). Most mineral contents of waxy black rice flour were higher than those of glutinous rice flour. The major fatty acids in the waxy black and glutinous rice flours were oleic acid (38.57% and 36.95%) and linoleic acid (38.60% and 39.10%). The major detected amino acids of both samples were aspartic acid, glutamic acid and arginine. Water binding capacity of waxy black rice flour (93.26%) was higher than that of glutinous rice flour (87.42%) . Swelling powers and solubilities of waxy black rice flour were lower than those of glutinous rice flour in according to increasing temperatures. Maximum absorbance wavelength (λ$_{max}$) and absorbance at 625 nm were similar between both samples. X-ray diffraction patterns of both samples showed traditional A type as Peaks 2$\theta$ at 15.1$^{\circ}$, 17.1$^{\circ}$, 18.0$^{\circ}$and 23.2$^{\circ}$. The relative crystallinities of waxy black and glutinous rice flours were 0.40 and 0.41, respectively.

• Korean journal of food and cookery science
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• v.16 no.3
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• pp.226-231
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• 2000

Injulmi, a kind of traditional Korean sticky rice cakes, was prepared with the mixed flours of waxy and black rices in different ratio(0% to 25% black rice flour), and their quality properties were studied. In the sensory evaluation, the best acceptance was shown in the samples with 15% black rice flour. The scores for hardness, coarseness. chewiness, and flavor were increased as the added amount of black rice flour increased. The moisture content of the samples ranged from 43 to 45%, and it was increased as the added amount of black rice flour increased. In color value, lightness(L value) was 27.43∼65.63. The redness(a value) was -2.01∼4.74, and the yellowness(b value) was -1.40∼4.59. The redness and blueness were increased by the increase of black rice flour. In the texture properties, the increase of added black rice flour increased the hardness, chewiness, and gumminess of Injulml, but decreased the adhesiveness. Based on the results, the optimal recipe for Injulmi added black rice flour was to make with 85% waxy rice flour ant 15% black rice flour.

• The Korean Journal of Food And Nutrition
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• v.28 no.4
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• pp.586-593
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• 2015

The baking properties of gluten-free rice bread with different percentages of corn starch and waxy corn starch were investigated. The specific gravity and color (L, a, b) of the dough as well as the appearance, color (L, a, b) and texture of the rice bread were analyzed. Replacement of rice flour with 1, 2.5, 5, 7.5 and 10% corn starch did not have a significant effect on the specific gravity and color of the dough. The volume and specific volume of the rice bread showed an increasing trend as the amount of added corn starch increased. The chewiness, gumminess and hardness of the rice bread showed a decreasing trend as the amount of added corn starch increased. Replacement of rice flour with 1, 5 and 10% waxy corn starch did not have a significant effect on the specific gravity and color of the dough. The color of the rice bread showed an increasing trend as the amount of added waxy corn starch increased. These results suggest that replacement of rice flour with 7.5% corn starch or 1% waxy corn starch is effective for gluten-free rice bread.

• Journal of the Korean Society of Food Culture
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• v.7 no.3
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• pp.213-222
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• 1992

This investigation was undertaken for the purpose of studying the quality and acceptability during storage at room or refrigerator temperature of Yackwa containing waxy rice flour substituted for 0,10,30,50,70% of the wheat flour. The storage periods were 0,15,30 and 45 days. Chemical composition, composition of fatty acids, and value, and peroxide values of Yackwa were measured. Sensory evaluation was done by a panel of 5 judges majoring in food and nutrition. The evaluation was repeated 4 times. Objective evaluation was done by rheometer and color difference meter. Chemical composition of Yackwa were $5.9{\sim}6.8%$ for moisture, $3.43{\sim}4.09%$ for crude protein, $22.35{\sim}27.65%$ for crude fat, $0.27{\sim}0.31%$ for ash, $15.6{\sim}18.4%$ for fructose, $10.6{\sim}13.7%$ for glucose, $0.34{\sim}1.0%$ for sucrose, and $0.79{\sim}2.37%$ for maltose, respectively. Fatty acid contents of Yackwa were $10.54{\sim}10.73%$ for palmitic acid, $4.12{\sim}4.18%$ for stearic acid, $25.8{\sim}26.9%$ for oleic acid, $51.6{\sim}52.1%$ for linoleic acid, and $0.27{\sim}0.34%$ for linolenic acid, respectively. Acid value and peroxide value of Yackwa during storage showed little change. As a result of sensory evaluation for Yackwa made various levels of waxy rice flour, there were no significant differences in most of characteristics between the samples supplemented with waxy rice flour to 30% of wheat flour at 0.01% level. By the color difference meter, the value of L (lightness) and b (yellowness) were increased by increasing the amounts of waxy rice flour, however, there were no significant differences at 0.1% level between the samples supplemented with waxy rice flour to 30% of wheat flour, on the other hand, the value of a (redness) was decreased by increasing the amount of waxy rice flour. In the textural characteristics, brittleness, and chewiness were increased by increasing the amounts of waxy rice flour, and by lengthening the storage period, on the other hand, resilience and cohesiveness showed vice versa. In the correlation coefficient between sensory characteristics and mechanical characteristics, overall acceptability in sensory evaluation correlated significantly with cohesiveness, chewiness, and the values of L, a, and b in mechanical test in most of samples(p<0.001).

• The Korean Journal of Food And Nutrition
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• v.14 no.1
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• pp.40-45
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• 2001

This study was conducted to investigate the effects of various emulsifiers on the quality of the waxy rice cake. Falling numbers of the waxy rice flour with monoglyceride, lecithin and control were not significantly different, but with sugar esther 0.5% and 1% showed higher value as 88.4 and 81 than control Initial pasting temperature of the waxy rice flour was 66.78$\^{C}$ and others were 66.45 ∼ 67.05$\^{C}$ by adding 0.5%, 1% of emulsifiers such as monoglyceride, lecithin, sugar esther. Waxy rice flour with 1% sugar ester showed the highest peak viscosity as like as falling number. Waxy rice cake wish various emulsifiers showed tendency to be slowly firming rate as compared with control. In all case, waxy rice flour with sugar ester 1% was considered to be more effective to the decrease of firming rate. Waxy rice flour with lecithin showed worse visual color than others and sugar ester provided best visual and sensory quality. After 5 days cold storage, waxy rice flour with sugar ester 1%\`s Aw was 0.875 and control\`s 0.911. These results suggested that water holding capacity of sugar ester was the best during storage.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.86-87
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• 1993

The steeping of waxy rice in water at $20^{\circ}C$ for 12 hr resulted in the decrease of protein, crude fat and ash contents. Water-binding capacity and swelling power (at $80^{\circ}C$) of waxy rice flour increased upon steeping. Maximum viscosity of waxy rice flour in 0.19 N sodium hydroxide solution was increased up to 6 hr steeping and decreased thereafter. The amylograph indices increased as the steeping time increased. The degree of changes in properties during steeping was different between two waxy rice cultivars.

• Korean journal of food and cookery science
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• v.25 no.2
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• pp.127-133
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• 2009

The aim of this study was to determine the optimum amount of waxy millet flour (WMF) to add to rice flour in the preparation of Sulgidduk (waxy millet rice cakes). According to the results, increasing the level of WMF in the formulation caused the moisture contents of samples to increase ($37.14{\sim}38.81%$). The L-value decreased with increasing additions of WMF whereas the b-value increased and the a-value did not differ by the addition of the flour. According to the mechanical evaluation results, hardness increased with increasing amounts of added WMF. Adhesiveness, cohesiveness, gumminess, and brittleness did not differ significantly and springiness was highest at the 30% level of WMF. From the sensory evaluation results, the 30% WMF samples received the highest overall-acceptability scores. In conclusion, according to its sensory and mechanical qualities, the optimal Sulgidduk formulation consisted of 30% WMF added to rice flour.

• Korean journal of food and cookery science
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• v.27 no.6
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• pp.745-754
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• 2011

To improve the textural properties of gluten free rice flour based products, the physicochemical and pasting properties of extruded non-waxy rice flours using extruder were investigated. The high yielding Tongil type rice variety, Hanarum was used. Hanarum rice flour was prepared by dry milling from soaked and dried rice grain. The operation conditions of twin screw extruder were 250 rpm of screw speed, $160^{\circ}C$ of barrel temperature, and 24, 27, and 30% of moisture content. Hanarum extruded rice flour (HERF) were lower in crude lipid and ash contents, but higher in crude protein than Hanarum rice flour (HRF). The color values of HERF showed significantly different (p<0.05) with different moisture contents. Water binding capacities, apparent amylose contents, and damaged starch of HERF were higher than those of HRF. Moisture contents affected water binding capacities of HERF. Solubility increased with increasing heating temperature and solubilities of HERF differed significantly (p<0.05). X-ray crystallinity was changed after extrusion cooking and that of HERF showed sharp peaks at $2{\theta}=18-20^{\circ}$. The pasting viscosities of HERF kept lower values (~ 10 RVU) constantly.

• Journal of Applied Biological Chemistry
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• v.51 no.6
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• pp.277-284
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• 2008

The objective of this study was to investigate the effect of soaking time on physicochemical properties of waxy rice, waxy rice flour and waxy rice starch. Waxy rice (WR), waxy rice flour (WRF), waxy rice starch (WRS) were soaked at $18^{\circ}C$ for 14 days and dried at $40^{\circ}C$. Dried samples were grounded and sieved using 180 mesh. Physicochemical properties of the three samples, such as swelling power, solubility, moisture sorption isotherms and pasting properties using rapid visco analyzer (RVA) and crystal pattern using X-ray diffractometer were determined. In all samples, soaking time greatly influenced moisture sorption isotherms but no typical pattern was shown. Swelling power was not greatly changed by soaking time in the three samples. Solubility increased with increasing soaking time in all three samples, indicating that some soluble particles were exuded during soaking. In RVA pasting properties, WR and WRF showed a similar pattern, while WRS showed different pasting properties, suggesting that rice protein plays a significant role in pasting properties. X-ray diffraction patterns of all three samples showed typical A-type crystal pattern suggesting that soaking did not affect crystalline region of samples.

• Korean Journal of Food Science and Technology
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• v.11 no.2
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• pp.99-104
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• 1979

Rheolegical and baking properties of blends containing 10, 20 and 30 % of rice flours (Milyang 23, non-waxy and Tongil waxy) with wheat flour were investigated. Milyang-wheat blends showed higher amylograph paste viscosities at all reference points than waxy-wheat blends. Rice-wheat four blends had shorter farinograph stability than f·heat flour; however, the dough development time was similar between two blends. Breads produced from either Milyang-wheat or waxy-wheat flour blends at 10% rice level were acceptable compared with breads produced from wheat flour.