• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.s01
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• pp.1-17
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• 1988

Rice Quality is considered to the five catagories ; the nutritional value: the characteristics of cooking. eating and processing: grain size, shape and appearance : milling yields: and storage characteristics. Because most rice is processed and consumed in whole-kernel form. the cooking and eating quality is of important and the physical properties of the intact kernel such as size, shape and general appearance are of particular significance in determining marketing quality. Eating Quality which can be directly evaluated by consumer's panel test is so complicate and variable, and thus the objective and simplified method of evaluation is required of using appropriate instruments. Even though many researches have been done to evaluate the eating quality in various aspects such as the texture of cooked rice kernels, amylogram analysis of rice powder, amylose content. gelatinization temperature. moisture absorption of rice kernel, and cooking characteristics, none of them is satisfied for the evaluation of eating quality. The improving eating quality should be also considered to many cultural factors. such as varieties, climatic and soil conditions, cultural method, handling after harvest. milling and storage conditions. In Korea, many researches in grain size. shape and appearance, and eating quality have been done with the varietal improvement mainly by rice breeders, but no effective method of evaluation was established. A few research have been done in the relationship between rice quality and cultural factors. In the future, research in rice quality should emphasize to establish the standard evaluation method in the physicochemical properties of rice kernels for application of varietal selection. and to develop cultural practices for the preserving quality characteristics of the varieties.

• Korean Journal of Food Science and Technology
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• v.5 no.1
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• pp.6-15
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• 1973

In an attempt to develop composite flours based on raw materials available in Korea, six domestic resources were investigated with respect to their physical and chemical properties, nutritive value and economy. The results are summarized as follows: 1) Flours from naked barley, sweet potato, potato, corn, defatted rice bran and defatted soybean were compared in respect of their proximate composition, thiamine content and protein score. 2) In color comparison, naked barley and defatted soy flours were comparable to wheat flour whereas corn and sweet potato flours were a little inferior. In raising power, naked barley and defatted soy flours were similar to wheat flour and others were inferior. 3) In maximum viscosity of flours by amylograph, naked barley, corn and potato flours were higher than wheat flour and others were lower. In viscosity in cooling, corn flour was similar to wheat flour and naked barley and potato flours were lower. Addition of $10{\sim}20%$ defatted soy flour into other flours generally caused the lowering of viscosity. Addition of emulsifiers such as glyceryl monostearate, calcium stearyl lactylate, Methocel and Emulthin into the flours manifested different effects on the amylogram. 4) In nutritional test by rat, diets consisting of naked barley, sweet potato, potato or corn flours, each containing defatted soy flour (at 10% level with exception of 20% for sweet potato flour) and naked barley flour fortified with lysine were similar to wheat flour in digestibility, but were superior in NPU and biological value. 5) In price estimation, sweet potato and corn flours were competitive with wheat flour, but naked barley flour was a little expensive. On the other hand, barley and sweet potato are promising in terms of domestic production.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.546-551
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• 1993

Rice flour obtained by four different milling methods, Pin mill. Colloid mill, Micro mill, and Jet mill, were used to investigate physico-chemical properties and product. Crude fat, ash, and protein contents of rice flours between different milling methods were similar. Blue value, amylose content, and damaged starch which related to properties of rice flour were reduced in the order that of Jet mill, Micro mill, Colloid mill, and Pin mill. Water absorption index, water solubility index, and water retention capacity increased as damaged starch increased. Hardness of gel(15%) is the highest value for Pin mill. The finer granules (Jet mill) had lower gelatinization onset(To) and peak(Tp) than any other rice flours. Those result are simillar with amylogram properties. Enthalpy of gelatinization increased as damaged starch increased. Jet mill had the highest score (p<0.05) of overall test in sensory evaluation and good paste properties.

• Korean journal of food and cookery science
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• v.7 no.4
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• pp.63-69
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• 1991

This study was undertaken for the purpose of studying the physicochemical propery of mungbean and texture of mungbean starch gels. Mungbean starch gel made with different levels of oil were tested to investigate the textural characteristics by mechanical test. The results are summerized as fallows: The content of moisture fat, protein, and ash in Seonwha mungbean were shown to be about 13.19%, 1.02%, 23.57% 3.13% respectively. Those of Seonwha mungbean crude starch were 12.48%, 0.63%, 0.94%, 0.13% respectively. The gain of dry crude starch from peeled mungbean was 22.48%. Water binding capacity of Seonwha mungbean crude starch was 183.1%. The pattern of change in swelling power of Seonwha mungbean crude starch for increasing temperature increased slowly to $70^{\circ}C$, and then increased rapidly. The pattern of change in solubility was similar to that of swelling power. The amylose and amylopectin content were 22.5%, 77.5%. Brabender hot-paste viscosities of mungbean crude starch at 8% and 10% showed the similar amylogram patterns with peak vicosity. By the Rheometer measurement result of 8% 10% mungbean starch gel, Hardness and Fractuability tended to be decreased as the addition level of oil increased. Elasticity, Adhesiveness, Chewiness, L, a, and b value tended to be increased as the addition level of oil increased.

• Korean Journal of Food Science and Technology
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• v.44 no.3
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• pp.300-305
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• 2012

The objective of this study was to evaluate quality properties, including amylose, alkali digestion value (ADV), and amylogram, of brown rice and germinated brown rice of some cultivars in Korea for rice processing products. The protein content of brown rice was significantly higher than those of germinated brown rice. The amylose content of the samples ranged from 17.09 to 18.85%. Alkali digestion value (ADV) of brown rice and germinated brown rice were described as a grade of 2-5 and 4-7, respectively. In a rapid visco analyzer (RVA) examination, pasting temperature of brown rice and germinated brown rice was $67.93-68.05^{\circ}C$. In addition, the pasting characteristics of brown rice were significantly higher than those of germinated brown rice. A texture analysis test showed that germinated brown rice Haiami had the lowest hardness and germinated brown rice Samkwang had the highest adhesiveness.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.805-809
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• 1997

The influence of cool temperature occurred during the booting stage in 1993 on quality of rice grain was compared with that in favorable weather of 1994. The mean and minimum air temperatures during the reproductive growth stage at the paddy field of Jinbu Substation, National Crop Experiment Station were 2.2~7.4$^{\circ}C$ and 2.0~8.9$^{\circ}C$ lower respectively in 1993 compared to those of 1994. Grain fertility and brown rice yield were 11.8％ and 0.4t /ha, and 84.3％ and 5.5t /ha in 1993 and 1994, respectively. There was no difference in amylose content between two years. However, protein content of brown rice in 1994 were 1.6％ lower than that of 1993. There was no difference in alkali digestion value of milled rice between two years. Gel consistency of rice flour was 45mm in 1993 and 59mm in 1994. Amylogram characteristics of rice flour produced in 1993 showed lower peak hot, cool, and breakdown viscosities, and higher consistency and setback viscosities. The palatability of cooked rice by sensory panel test was considerably better in 1994 rice than in the rice of cool year.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.32-37
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• 2004

Effects of mushroom powder on physicochemical characteristics of dough and bread-making properties were studied. In mixogram test, addition of 2-10% mushroom powder increased water absorption from 67,0 to 79%. Peak time, peak height, band width, and seven minute height of mushroom-wheat flour composite were similar to those of control. Sedimentation and P.K. values decreased with increasing amount of mushroom powder In amylogram test, no significant difference was observed in gelatinization temperature between control and mushroom powder-added dough. Peak viscosity increased with increasing amount of mushroom powder, Highest loaf volume was attained when 2 and 4% mushroom powders were added, whereas decreased above 6%. Bread weight and L value of crust increased with increasing amount of mushroom powder whereas 'a' value decreased. As the amount of mushroom powder increased, L value of crumb color decreased. No significant difference in springiness and adhesiveness was observed between control and mushroom-wheat composite flour bread whereas chewiness and gumminess, increased with increasing amount of mushroom powder, Hardness generally increased as the amount of mushroom powder increased. Mushroom powder caused bread staling at both storage temperatures ($4^{\circ}C\;and\;25^{\circ}C$). Although sensory value decreased with increasing mushroom powder, use of mushroom powder to replace up to 4% wheat flour is recommended in making bread.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.264-274
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• 1993

This study was carried out to assess the agronomic characters and physicochemical properties of floury and chalky-endosperm mutant lines induced by chemical mutagen treatment to rice varieties, Hwacheongbyeo and IR24. Linkage analysis of a floury-endosperm gene was carried out using linkage testers. The grain size of brown rice of the mutants was smaller than that of the original varieties. The l, 000-grain and 1$\ell$ weight were lighter in the mutants compared with those in the original varieties. The compound starch granules in the endosperm cell of the mutants showed a loosely-packed crystalline structure. Amylose contents in mutants ranged from 16.9 to 28.5%. Crude protein contents of the mutants were not significantly different from the original rice variety, Hwacheongbyeo, but white core mutant(line 47106) derived from IR24 showed higher protein(l1.32%) compared with IR24(8.30%). The mutants showed slightly harder gel characteristics, and much lower viscosity in Amylograph than original varieties. Steamed rice-cakes from mutant lines showed greater volume than those from original varieties. During the process of alcohol fermentation, Brix in the mutants(especially floury mutants) decreased faster and the alcohol production after 10-day fermentation was much greater in the mutants than in the original varieties. Three different gene loci for floury endosperm characteristics were identified from the allelism test among mutant lines, and the genes were tentatively symbolized as flo-a, flo-b and flo-c, respectively. A floury gene, flo-a, was linked with lg(liguleless) gene in the linkage group N, with R.V. 5.76$\pm$1.72%.