• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.721-726
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• 1996

Fatty acid composition and phenolic acid content of rice with different milling fractions were analyzed to provide basic data for nutrition, processing and storage of rice. Major fatty acids of rice were palmitic, oleic and linoleic acids and their respective contents were 20.0%, 33.3% and 43.0% of embryo, 17.3%, 45.1% and 34.5% of rice bran and 23.4%, 26.2% and 46.1% of milled rice. Outer fraction had a high content of oleic acid but a low content of linoleic acid in rice bran. As milling yields increased in milled rice, oleic acid content increased, but palmitic acid, linoleic acid, stearic acid and linolenic acid contents decreased. Contents of free, esterified and insoluble bound phenolic acid extracts from bran were 321.0mg%, 299.7mg% and 212.4mg%, respectively. Milled rice contained 118.0mg% of free phenolic acids, 56.0mg% of insoluble bound phenolic acids and no esterified phenolic acids. Rice bran contained 86.2% of ferulic acid as a principal phenolic acid. It also contained 35.7~36.6% of sinapic and syringic acids, 16.7% of p-coumaric acid and 0.13% of vanillic acid as minor component. Contents of total phenolic acid, expressed in terms of tannic acid, among rice with different milling fractions was highest in embryo. It was higher in outer fraction in bran, but rarely detected as fractionation of the component with milling in milled rice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1366-1372
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• 2010

This study investigated the quality characteristics of brown rice vinegar (agitated culture and static culture) derived from brown rice Takju with different types of yeasts. The alcohol content by yeast was the highest in B (brown rice Takju produced by S. cerevisiae GRJ) at 14.3% and the titratable acidity was less than 0.6% in all ranges. When quality characteristics of agitated and static culture brown rice vinegar using them were compared, acidity of agitated culture vinegar recorded the highest level or 6.05% at 7 day of fermentation DV (brown rice vinegar produced by S. kluyveri DJ97) with the initial acidity of 1.0% and the initial pH of 3.9~4.0, and AV (brown rice vinegar produced by S. cerevisiae JK99), CV (brown rice vinegar produced by S. cerevisiae H9) and BV (brown rice vinegar produced by S. cerevisiae GRJ) recorded as 5.64, 5.55 and 5.32%, respectively. In addition, acidity of static culture vinegar increased continuously to 5.01~5.31% until the 14 day of fermentation and then tended to decrease slightly from the 16 day of fermentation. Difference in acidity and pH of brown rice vinegar according to types of yeast was not significant. Comparison of free amino acid of brown rice vinegar showed that for agitated culture brown rice vinegar, the content of total free amino acid was higher in the order of BV, DV, AV and CV and the content of essential amino acid was the highest in BV by recording over 1,000 ppm. The content of total free amino acid of static culture brown rice vinegar was higher than that of agitated culture vinegar in all ranges and especially static culture brown rice vinegar contained more serine, alanine, valine, isoleucine, leucine and $\gamma$-aminobutyric acid than agitated culture vinegar. In particular, $\gamma$-aminobutyric acid recorded over ten times higher level or 456.91~522.66 ppm. From these results, quality characteristics of brown rice vinegar was affected by acetic acid fermentation methods rather than types of yeast. However, as future aging process is expected to change flavor components and sensory characteristics, studies on various quality factors of vinegar are needed.

• Research in Plant Disease
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• v.17 no.3
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• pp.280-287
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• 2011

This investigation was undertaken to survey toxigenic fungal contamination of various rice samples in 93 rice processing complexes (RPC) in Korea. Rice was grown in 2009 and the samples were collected in 2010. Seven types of rice samples such as unhusked, brown, blue-tinged, discolored, polished, half-crushed, and rice husks were obtained from each RPC. One-hundred and five grains of each sample were placed on PDA plates after surface disinfection. The incidence of fungal contaminants was 26.8%. Aspergillus spp. was the most dominant fungal contaminants and Fusarium spp. was the most frequently occurred in samples. The heaviest Fusarium contamination was found in unhusked grain, rice husks, and bare blue-tinged rice and followed by colored rice whereas broken rice was the least contaminated. Regional difference of fungal contamination was distinctive. Fusarium incidence in the rice samples from southern region of Korea including Jeolla and Gyeongsang Provinces was higher than those from central region including Chungcheong, Gyeonggi, and Gangwon Provinces. In contrast to Fusarium spp., Aspergillus spp. and Penicillium spp. were dominated in brown and polished rice samples and their incidences were more severe in central region than southern region. The major contaminants shown more than 1% of kernels infected were Aspergillus (5.0%), Fusarium (2.0%), Alternaria (1.4%), Dreschlera (1.3%), Penicillium spp. (1.3%), and Nigrospora spp. (1.0%). Collectotrichum, Pyricularia, Myrothecium, Epicoccum, Cladosporium, Moniliella, Gloeocercospora, Chaeto- mium, Curvularia, Phialopora, Acremonium, Gliomastix, Trichoderma, Rhizopus, Phomopsis, Paecilomyces, Genicularia, Geotrichum, Acremoniella, Rhizoctonia, Phoma, Oidiodendran, and Candida spp. were among the rest observed at low incidence. The major contaminants of rice samples were well-known as toxigenic fungal genera so toxin producibility of these fungal isolates is necessary to be examined in future. It is also needed to study Myrothecium spp. on species level as it was detected for the first time in rice.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.136-140
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• 1985

Optimal quality retentions of cooked rice packed in retort pouch were simulated by computer using various thicknesses of retort pouch (5 to 24mm) and process temperatures (110 to $150^{\circ}C$). Optimal conditions were chosen by the minimal c-values and maximal thiamine retention when good bacteriological lethality (12D processing) was obtained. From the results of calculations, it were shown that the better quality retentions of high tharmal processing can be obtained below pouch thickness of l0mm and that the thickness of pouch is critical factor at higher processing temperature.

• Journal of the Korean Society of Food Culture
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• v.34 no.6
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• pp.779-784
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• 2019

The purpose of this study was to optimize the rice protein extracted using a response surface methodology. The experiment was designed based on a CCD (Central Composite Design), and the independent variables were the high pressure (X₁, 0-400 MPa) and processing time (X₂, 0-10 minutes). The results of the extraction content (Y₁), residue content (Y₂), and recovery yield (Y₃) were fitted to a response surface methodology model (R²= 0.92, 0.92, and 0.93, respectively). Increasing the pressure and processing time has a positive effect on the extraction content (Y₁), residue content (Y₂), and recovery yield (Y₃). Therefore, these high-pressure conditions (independent variables) can significantly affect the improvement in rice protein extraction efficiency. Thus, the optimal conditions of X₁ and X₂ were 400 MPa and 10 min., respectively. Under these optimal conditions, the predicted values of Y₁, Y₂, and Y₃ were 62.93, 57.53 mg/g, and 91.76%, respectively.

• Food Science and Preservation
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• v.23 no.7
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• pp.953-959
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• 2016

The quality characteristics and processing of rice cake (Backsulgi) with rice flour containing Lactobacillus plantarum CGKW3 by spray-drying (LP-B) were investigated. The LP-B was applied at ratios of 10, 20, and 30 (w/w), and the moisture contents and pH were 33.39%~36.70% and 5.81~5.46, respectively. The L value of LP-B increased as the rice flour decreased, while the a and b value increased as the LP-B increased. The texture profiles showed that Backsulgi prepared with LP-B mixture had higher hardness, cohesiveness, springiness and chewiness than 100% rice flour. The pH of LP-B Backsulgi (LP-B20 and LP-B30) did not differ during 6 days at room temperature. The total bacteria in Backsulgi prepared LP-B20 and LP-B30 Backsulgi was $10^4CFU/g$ after 2 days of storage at room temperature. The shelf life of Backsulgi prepared with LP-B20 and LP-B30 were extended by about 2 days when compared with the control at room temperature. Sensory evaluation showed that Backsulgi without LP-B20 had higher scores in terms of appearance, color, flavor, taste, texture, hardness and overall acceptability than Backsulgi without 100% rice flour. In conclusion, the results demonstrate that LP-B20 may prove quite useful as a Backsulgi flour with desirable properties.

• Journal of Food Hygiene and Safety
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• v.30 no.4
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• pp.343-349
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• 2015

A study survey about the rice cake producers completing the food hygiene education in Korea was investigated by characteristics of the rice cake business. The difference between their online and offline awareness of food hygiene education were compared. The average age of rice cake producers is 50 (40.1%), with a high school education (52.6%), 10-20 years of service (34.3%) showed the highest percentage. In relation to sales and work area, workshop personnel are engaged in two (79.5%), An area of less than $99.17m^2$ (92.0%), rent (60.2%) with most paying a monthly rental amount of less than 1 million won (54.8%). There were 228 accident cases in three years (an annual average of 2.4%), manufacturing, Processing the item number was less than 20 types of analysis (86.7%). Case of food hygiene education graduates are women, the lower the age, the higher the education level, was preferred online. Online education was chosen because of 'time, economic, convenience'(73.7%). Online graduates have recognized that health education is more conducive to business. There was no significant difference between the sales online and offline graduates. For hygienic management response was that online graduates are well above the 7.4% offline graduates. Online and offline graduates 60.7% appeared to be more satisfied than the previous training institutions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1407-1414
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• 2014

Physicochemical properties of rice-based expanded snacks extruded with rice flour, high amylose starch, and isolated soy protein were investigated using a twin-screw extruder. The ingredients were extruded at various feed moisture contents (19~23%) and screw speeds (200~400 rpm) at a constant feed rate (43.4 kg/hr). Bulk density and apparent density of rice snacks were 0.06~0.21, and 0.55~0.65 respectively. Bulk density, apparent density, water absorption index, and breaking strength of rice snacks increased with increasing feed moisture content and decreasing screw speed. However, expansion and water solubility index of rice snacks increased with decreasing feed moisture content and increasing screw speed. Hunter's color L values of rice snacks was lower with increasing screw speed at feed moisture contents of 19% and 21%, but was not significantly different from a feed moisture content of 23%. On the other hand, a and b values of rice snacks were higher with increasing screw speed a feed moisture content of 19%. X-ray diffraction intensity of rice snacks decreased with decreasing feed moisture content and increasing screw speed. X-ray diffraction of rice snacks was V-type at feed moisture contents of 19% and 21% and screw speeds of 300, and 400 rpm. In the microstructure of the cross section of rice snacks, air cells in rice snacks were not well formed, and cell walls were thicker with increasing feed moisture content and decreasing screw speed.

• Korean journal of food and cookery science
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• v.23 no.6
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• pp.908-918
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• 2007

To prepare ready-to-use rice flour as de novo material for processed rice foods, glutinous(W) and normal rice grains (N) were soaked for 1, 8, and 12 hours prior to processing. One half (DG) was air-dried and milled, and the other (WG) was milled and air-dried. General, morphological and pasting properties of the flours (NDG, NWG, WDG, WWG) were compared to those of a control (raw milled rice without soaking). The general compositions of the rice flours varied with soaking. Crude ash was considerably decreased at the beginning of soaking (1 hour). With the soaking, the rice flour, having polygonal shaped particles and a layered surface, acquired particles with smooth edges, which were then uniformly distributed. Additionally, the WG flour was lighter and had a lower ${\Delta}E$ value than the DG flour, due to a higher L and less +b as a result of soaking. Compared to the control, the WBC of the normal rice flour was decreased significantly with soaking, and the WG flour had significantly lower WBCs than the DG flour. Stirring number (SN), an indicator of ${\alpha}-amylase$ activity, was highly and significantly correlated with WBC (r=-0.85, p=0.0001) in the normal rice flour. At $80^{\circ}C$, the SP and solubility of all the soaked rice flours were much higher than those of the control. Positive (r=+0.85, p=0.0001) and negative (r=-0.61, p=0.02) correlations between the SP and solubility of the normal and glutinous rice flours were found, respectively. Using RVA, the pasting temperature of NDG was lower than that of NWG (p<0.0001). The peak viscosities of all the soaked flours were significantly decreased with soaking (p<0.0l), with the highest viscosity in the normal rice flour soaked for 8 hrs. Total setback, indicative of retrogradation, was lower in NDG than in NWG, with the lowest setback at 8 hrs of' soaking. Based on these finding, the NDG flour with 8 hrs of soaking was less damaged, and had a lower total setback and lower pasting temperature, which would make it an appropriate rice flour for commercial mass production.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.1
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• pp.9-16
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• 2022

Rice is one of the most important staple foods in Wnju, Jeonbuk, South Korea. However, rice consumption has dramatically decreased as eating habits have diversified owing to rapid economic growth. Recently, floury endosperm rice varieties have been developed to invigorate the rice processing industry, because dry-milled rice flour is economically and environmentally suitable for massive rice flour distribution. The National Institute of Crop Science has developed 'AromaT', an early-maturing black rice with floury-endosperm, suitable for tea and dry milling. 'AromaT' was derived from a cross between 'Suweon542' as the floury endosperm source and 'Heugjinju' as the black and aromatic source. In this study, 'AromaT' and its parents, 'Suweon542' and 'Heugjinju', were analyzed for agronomic traits, anthocyanin content, and their major physicochemical properties by different planting date. The field experiment was conducted in Wanju, Jeollabuk-do Province, South Korea, in 2019. The transplanting dates were May 30 (ordinary season), June 25 (double-cropping season), and July 10 (late season). The yield performance of brown rice 'AromaT' was 330 kg/10 a in the double-cropping cultivation method and was the highest among the transplanting dates. The floury endosperm of 'AromaT' was derived from 'Suweon542' containing 'flo7', located on chromosome 5 and known to control floury endosperm. With the late planting date, the anthocyanin content of 'AromaT' was 570.5 mg/100 g, much higher than that of 'Heugjinju' (376.3 mg/100 mg). The brown rice of 'AromaT' also exhibited the pop-corn-flavoring 2-acetyl-1-pyrroline, exclusively detected in aroma rice varieties. The average particle sizes of 'AromaT' and 'Suweon542' were 67.12 ㎛ and 70.9 ㎛, respectively, lower than that of 'Heugjinju' (95.5 ㎛) with a black transparent endosperm. The average damaged starch content of 'AromaT' was 8.1%, lower than that of 'Heugjinju' (10.05%) and Suweon542 (9.5%). As a result, 'AromaT' with high anthocyanin content, fine particle size, and low damaged starch content is expected to provide a new rice material in various processing fields.