• Food Science and Biotechnology
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• v.15 no.2
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• pp.232-237
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• 2006

Bacillus cereus group comprising B. cereus, B. thuringiensis, and B. mycoides was differentiated by polymerase chain reaction (PCR) and colony morphology. Prevalence of B. cereus group in rice and distribution of enterotoxin genes were determined as possible food poisoning agents. PCR using primers targeted for gyrB and cry genes could distinguish B. thuringiensis from B. cereus, and B. mycoides was differentiated by rhizoid morphological characteristics on nutrient agar. Among 136 rice and their processed products, prevalence of B. cereus group was 40%. B. cereus group consisted of 54 B. cereus, 11 B. thuringiensis, and 1 B. mycoides. Major isolates were B. cereus, with B. thuringiensis detected up to 10% among edible rice tested. Five enterotoxin genes, hbl, nhe, bceT, entFM, and cytK, were broadly distributed among B. cereus group, especially in B. cereus and B. thuringiensis. Prevalence of B. cereus group in rice and enterotoxin distribution suggest B. thuringiensis and B. cereus are toxigenic strain that should be controlled in rice and its products.

• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.509-512
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• 2011

To study the effect of freezing rate on the quality of freeze-dried rice porridge, freeze-dried rice porridge products were prepared with rice porridge pre-frozen at three different temperatures of -20, -40, and -70$^{\circ}C$. The porridge properties such as microstructure, mechanical properties, textural properties, and rehydration rate were determined. Scanning electron microscopy images indicated that fewer air cells were obtained with a larger size of freeze-dried rice porridge frozen at -20$^{\circ}C$ compared with that frozen at -40 and -70$^{\circ}C$. In contrast, quick frozen products at -70$^{\circ}C$ had more dense texture with higher mechanical strength, whereas slow frozen products exhibited higher rehydration rates than those of quick frozen products. In conclusion, the proper choice of pre-freezing temperature plays a decisive role when preparing freeze-dried rice porridge with optimum quality and convenience.

• Food Science of Animal Resources
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• v.38 no.1
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• pp.180-188
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• 2018

The market size of home meal replacement (HMR) products has been gradually growing worldwide, even in Korea. In Korean HMR products, meat is the most important food ingredient compared with rice and vegetables. Therefore, this study aimed to evaluate changes in physiochemical and sensory aspects of beef under different preparation processes. For preparing four treatments, beef eye of round (ER) added with salt and sugar (treatment 1) and that without salt and sugar (treatment 2) were mixed with rice and frozen at $-50^{\circ}C$. Beef ER without salt and sugar was also topped onto the rice and frozen (treatment 3), and that was topped onto the rice and precooled before freezing (treatment 4). Physiochemical analyses included cooking and drip losses, shear force, color, salt soluble protein, and sensory attributes were tested. The results showed significantly higher drip loss and total loss in beef ER samples 1 and 2, which were mixed with rice, compared to beef ER samples 3 and 4, which were not mixed with rice. A significantly higher discoloration was also observed in beef ER samples 1 and 2, compared to that in samples 3 and 4. In the partial least squares regression (PLSR) analysis, beef ER sample 4 (precooled before freezing) was highly related to sensory attributes, such as flavor, overall acceptability, and juiciness, and far from non-preferred shear force. As a result, beef ER in HMR sample 4 was the most preferable to the sensory panel, and it had the most desirable physicochemical analysis outcomes.

• Korean journal of food and cookery science
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• v.28 no.6
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• pp.813-820
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• 2012

To develop the high quality gluten-free rice products with health functionality and desirable texture with moistness, the physicochemical properties of extruded rice flours prepared from the mixture of germinated brown and white rices were investigated. The domestic organic Samgwangbyeo was used to make white and germinated brown rices. White rice (WR) was dried after soaked for 6 h at $15{\pm}3^{\circ}C$ and mixed with germinated brown rice (GBR) with different mixing ratios (100:0, 75:25, 50:50, 25:75, 0:100). The operating conditions of twin screw extruder were 250 rpm of screw speed, $120^{\circ}C$ of barrel temperature, and 25% moisture content of rice flour. The ash, crude protein and crude lipid contents were significantly different (p<0.05) and those of extruded GBR were the highest values, but those of extruded WR were the lowest. The color difference of extruded WR based on white plate showed the lowest among them. The water binding capacity (334.16%), swelling power (8.83 g/g), solubility (33.13%), and total starch (79.50%) were the lowest in extruded GBR. The viscosities of all extruded rice flours by RVA were maintained during heating. The peak and total setback viscosities of extruded rice flours ranged 127-352 and 58.0-85.5 cP, respectively. The novel food biomaterial from germinated brown rice as well as white rice was developed by twin screw extruder. The extruded rice flours control the moistness to improve the texture and also have functional materials, dietary fiber, GABA, and ferulic acid, etc to increase quality of gluten free rice products.

• Microbiology and Biotechnology Letters
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• v.9 no.4
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• pp.253-261
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• 1981

Fermented foods available in Korea may be classified into four groups, namely, fermented soybean products, fermented cereal products, fermented vegetable products, and fermented fishery products based on raw materials used. The representative fermented foods based on soybean are Kanjang(soysauce), Doenjang(fermented soybean pastes), and Kochujang(red pepper added-fermented soybean paste). Such fermented products are made using Meju(functioning as a starter and prepared by fermentation of steamed soybean mash) as an essential ingredient, and used widely as a soup base and/or in seasoning side-dishes for everyday meals year around. Excepting Sikhae, all fermented products based on rice and other cereal grains are of alcoholic nature. Takju (Makgeolli) used to be made using rice as the major raw material, however, mainly due to the shortage of rice in recent years, other cereals, such as, barely, corn, and wheat flours are also used to replace rice today. Owing to such changes in the raw materials. the popularity of Takju has been somewhat reduced, yet it is still widely consumed in rural areas. Although Chungju is a popular rice wine with superior qualify over Takju, the amount consumed is considerably limited. The highest qualify rice wine, Bupju, in particular, is made by a low temperature fermentation using glutinous rice. Kimchi is an unique fermented vegetable product of long tradition in Korea. Although it was for consumption mainly in winter season serving as a source of vitamins, today it is widely used throughout the year. Except Kkakdugi and Dongchimi, all of the fermented vegetable products contain salted Korean cabbage as an essential item, while they abound in varieties depending on material composition and methods of processing, and also on seasons and localities Next to Kimchi in this category is Kkakdugi made of raddish in popularity and quantity consumed. The four groups of fermented food products described above are reviewed in some detail and evaluated in terms of their nutritional significances, processes and microorganisms involved. and their commercial potentials. Jeotkal (or Jeot) is a name given to all fermented products of fishery origin. A number of Jeot can be prepared by adding salt and allowing fermentation to the raw materials such as shrimp, anchovy octopus, clam, oyster, etc.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.45-49
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• 2001

This research was conducted to study the characteristics of the extruded products prepared from blends containing fixed amounts of frozen pollack (20%) and defatted soy flour (5%) and varying amounts of rice and corn flour using laboratory-scale single-screw extruder. Extrusion conditions were set at 27% feed moisture, $160^{\circ}C$ process temperature and 170 rpm screw speed. Results showed that there was almost no difference in proximate compositions among all extruded products. The product made from 100% rice flour had the highest expansion ratio, the lowest bulk density and the lowest shear force (P<0.05). Also, this product was the highest in L value and had the highest preference in sensory evaluation. Consequently, the addition of frozen pollack and defatted soy flour to rice flour could make desirable expanded extruded products. This study will form the basis for future development of rice snacks containing frozen pollack.

• Nutrition Research and Practice
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• v.1 no.1
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• pp.8-13
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• 2007

Cooked rice is a staple food for Koreans which provides more than 60% of daily required energy. In 1960's, Koreans ate 600 g-800 g of cooked rice per meal and the energy obtained from cooked rice was almost more than 80% of the daily intake of energy. However, as the economy of Korea improved, the major industry has been shifted from agriculture to various manufacturing industries and the export of those products has been increased thus increasing the national income but decreasing the farming population and thus rice consumption have been decreased. It has been said that the decreased rice consumption is caused solely by decreased farming population but it can also be said that the decreased farming population is caused by decreased rice consumption. As the national income increases, the type of foods people consume have become diversified. Various processed foods such as convenience food or ready-to-eat food have been widespread, which are mostly made of wheat flour rather than rice.

• Korean Journal of Pharmacognosy
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• v.35 no.4 s.139
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• pp.346-349
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• 2004

Black colored rice has long been consumed in Oriental countries and is considered to be a healthy food. Extracts from rice with three different colors (white, black, and green) were prepared by using 80% MeOH and subjected to biological screening activities. The levels of antioxidative activity of black colored rice cultivars such as C3GHi and Heugjinjubyeo in radical scavenging activity were higher than those of the related white and green rice ones. When the effect of the extracts on thrombin time inhibition was analyzed, the extract from Heugjinjubyeo showed a dose-dependent suppressive activity. In addition, all the extracts tested did not inhibit the cyclooxygenase activity. Therefore the health benefits of the colored rice are attributed in part to their unique phytochemical composition such as high level of anthocyanin pigments with other minor strong antioxidant components for potential use in neutraceutical or functional food formulations.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.10-10
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• 2022

The concern about food security is rising as the unstable situation of food supply and demand due to the Covid-19 pandemic, climate change, and turbulent political situation. Korea's global food security index (GFSI), analyzed by the Economist Group, is considered good, but the level continuously decreases in comparing food security levels by country. In particular, Korea is highly dependent on food imports, and food and grain self-sufficiency rates continuously decrease. Therefore, increasing those rates to strengthen food security is urgent. Among the major grains, the self-sufficiency of wheat, com, and soybeans, except rice, is relatively low. Unlike the decrease in the annual rice consumption, the annual wheat consumption has been continuously maintained or increased, which is required public-private efforts to increase the self-sufficiency rate of wheat. Applying the government's policies implemented to increase the self-sufficiency rate of rice in the past will help increase the self-sufficiency rate of wheat. In other words, expanding wheat production and infrastructure, stabilizing supply and demand, and establishing a distribution system can be applied. However, the processing capability of wheat and rice is different, which is necessary to improve wheat quality and processing technology to produce consumer-preferred wheat-based products. The wheat and flour quality can be improved through breeding, cultivation, post-harvest management, and milling. In addition, research on formulation, processes, packaging, and storage to improve the quality of wheat-based products should be done continuously. Overall, food security could be strengthened by expanding wheat production and consumption, improving wheat quality, and increasing wheat self-sufficiency.

• Korean Journal of Food Science and Technology
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• v.13 no.1
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• pp.6-14
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• 1981

In an attempt to make dried noodles with composite flours utilizing rice and wheat flours, noodle-making characteristics were improved by the addition of popped rice and wheat flours to rice flour. Their quality was studied in terms of physical properties, noodle-making characteristics, cooking quality test and sensory evaluation. Dried noodle of the composite flour was produced by the conventional method. The results are summerized as follows; 1. In comparing the composite flours, the rice flour containing 30% popped rice flour had a lower maximum viscosity than that with 40% popped rice flour by method of amylograph. The composite flour(20% rice+30% popped rice+50% wheat flour) with added 2% xanthan gum showed the viscosity characteristics which was similar to that of wheat flour. 2. Addition of $1.5{\sim}2.0%$ xanthan gum and $40{\sim}50%$ wheat flour to rice and popped rice flour mixture helped to improve the noodle making properties and the cooking quality, and the noodle making properties and the cooking quality of the mixed flour were almost the same as those of wheat flour alone. 3. The composite flour (rice+popped rice+wheat flour) with xanthan gum showed a higher score in sensory evaluation than that without xanthan gum. The general acceptability scores obtained with the noodle products made of the composite flours with 30% popped rice flour was not significantly different from that of noodle products made of wheat flour alone. However, the noodle products made of the composite flours showed rather higher scores in odor and palatability than the products made of wheat flour alone.