• Food Science and Preservation
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• v.22 no.6
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• pp.823-830
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• 2015

Physicochemical properties of five commercial rice products were investigated in order to select the appropriate rice varieties for the preparation of frozen fried rice. Among the evaluated rice varieties, Onnuri (16.06%) had the highest amylose content, while Beakjinju (11.83%) had the lowest. The water absorption index ranged from 1.45 to 1.65 g/g. Regarding the Hunter's color values, the L and a values of all rice varieties decreased while the b value increased with freezing-storage following the cooking process. The initial pasting temperature showed no significant differences among the five rice varieties. The highest viscosity (peak, trough, and final) and setback were found in the Sindongjin, while the lowest breakdown was found in the Baekjinju variety. Hardness, chewiness, and cohesiveness of all five cooked rice varieties decreased while their adhesiveness increased after freezing-storage. Under electron microscopy scanning, pores were observed inside the tissue of frozen cooked rices manufactured from Baekjinju and Hopum varieties, while substantially smooth tissue structure was observed in Sindognjin, Onnuri, and Ilmi rice varieties.

• Food Science and Preservation
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• v.22 no.6
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• pp.811-816
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• 2015

The purpose of this study was to determine the optimum amount of Artemisia annua L. powder for adding rice flour. The A. annua powder was added to the rice flour at ratios of 1% (30 g/3 kg), 2% (60 g/3 kg), 3% (90 g/3 kg, w/w). As the amount of A. annua powder in rice cake dough increased, carbohydrate, ash content, total amino acid, and dietary fiber contents increased whereas the moisture content decreased. Hunter's L value decreased as A. annua powder content increased. On the contrary, the a- and b values increased. The sensory score of the rice cakes containing 30 g of A. annua powder was the highest of all the rice cakes tested. Based on these results, adding A. annua powder could improve the quality and sensory characteristics of rice cake.

• Food Science and Preservation
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• v.14 no.5
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• pp.439-444
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• 2007

This study was carried out to analyze the quality change of salted mackeral treated with extracts of edible plan(Diospyros kaki, Teucerium veronicoides and Zanthoxylum schinifolium) during storage for develope of preparation methods and high quality of mackerel. The Hunter's color values of salted mackerel was not changed during strange. L, a and b value of salted mackerel teated with Korean herbal extracts was lower changed than those of control(mackerel not treated extracts of edible plants). Adhesiveness, and viscosity of salted mackerel was higher at $4^{\circ}C$ during storage than those at $25^{\circ}C$, and was higher in groups treated extects of edible plants at early storage than those in control group. Hardness was low in the salted mackerel treated extracts of edible plane and control group during storage. The salted mackerel treated Z. schinifolium extracts was the highest scores in sensory evaluation among groups.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.3
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• pp.372-376
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• 2009

Physicochemical changes in persimmon were examined during natural organic acid fermentation. Major organic acids in raw persimmon juices were lactic acid (980 mg%) and acetic acid (245 mg%). The content of acetic acid was continuously increased during the whole period of fermentation up to 3 years. Glucose was the dominant free sugar, but the content was decreased after 20 days of fermentation. Most of the glucose was converted to ethanol until 40 days after initiation of acid fermentation. L- and a values of Hunter's color in fermented persimmon juice, which was naturally exuded from persimmon fruit as fermentation continued, increased gradually, while b value decreased. Acetic acid (1584 mg%) was the most abundant organic acid followed by lactic acid (712 mg%) and citric acid (48 mg%) in a persimmon fruit juice after completion of 3 year fermentation. A minute amount of residual free sugars, mainly glucose, even after 3 years of fermentation may cause changes in quality characteristics while storage for edible use.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.628-634
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• 2003

To investigate the effects of storage and pasteurization temperature on the quality of kiwi juice $(13.5^{\circ}Brix)$, the Kiwi juice was pasteurized at 65, 75 and $85^{\circ}C$ for 15 sec. The microbial, physicochemical measurements and sensory evaluations were conducted at the same condition during storage at 4 and $25^{\circ}C$ for 30 days. Most of the vegetative bacteria cells in kiwi juice were destroyed by heat treatment over $65^{\circ}C$, and they did not actively grow in kiwi juice after pasteurization. The D values of bacteria in kiwi juice by tubular type of heating exchange were 4.17, 1.47 and 0.81 sec at 65, 75 and $85^{\circ}C$, respectively. The growth of microorganisms during storage were not detected in the most samples. The amounts of vitamin C decreased as the pasteurization-storage-temperature and storage time increased. While reducing sugar increased as the pasteurization-storage temperature-storage time increased, it decreased rapidly after 20 days of storage. Hunter's color values L, a and b of stored kiwi juice were decreased at all storage conditions, browning reaction rate increased as the pasteurization-storage-temperature was decreased.

• Korean journal of food and cookery science
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• v.21 no.2 s.86
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• pp.149-154
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• 2005

The objective of this research was to estimate the shelf-life of 4 kinds of Korean soup (Yukkaejang, Sagol-woogeojitang, Kalbitang, and Seolleongtang), under an accelerated experiment, based on the changes in the selected physico-chemical, microbiological and sensory characteristics. The 4 kinds of Korean soup (Yukkaejang, Sagol-woogeojitang, Kalbitang and Seolleongtang) were 1.sated at $121^{\circ}C$ for 30 min. and the shelf life was evaluatedthrough accelerated experiment, based on tile changes in the physico-chemical, microbiological and sensory characteristics. No viable cells were detected in any of the treatments and no significant differences were shown in pH, TBA and Hunter's color values for 3 weeks at $37^{\circ}C$. The periods found to be acceptable by sensory evaluation were 1 days for Yukkaejang and Kalbitang, 14 days for Sagol-woogeojitang, and 21 days for Seolleongtang. For an assumed $Q_10$ value of 2.5, shelf-life was predicted as 109 days for Yukkaejang and Kalbitang, 219 days for Sagol-woogeojitang, an d 328 days for Seolleongtang at $5^{\circ}C$, suggesting that these 4 kinds of Korean soup are suitable for commercial distribution.

• Food Science and Preservation
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• v.15 no.5
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• pp.642-647
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• 2008

This study investigated the microbiological and sensory characteristics of Kongnamul muchim stored with gamma-irradiated red pepper powder at $4^{\circ}C$. Total aerobic microbes in raw Kongnamul muchim were 5.72 log CFU/g in the red pepper powder and 2.40 log CFU/g in the garlic used during storage, but were not detected n other raw materials. Coliform bacteria and fungi were found, at 3.11 and 3.48 log CFU/g respectively, only n the red pepper powder. Microorganisms in Kongnamul muchim stored with gamma-irradiated (10 kGy) red pepper owder were not detected over 3 days of storage at $4^{\circ}C$. The pH, Hunter's color value, and sensory characteristics id not change significantly on storage. These results suggest that the addition of gamma-irradiated (less than 10 Gy) red pepper powder could improve the microbiological safety of Kongnamul muchim without changing desirable ensory characteristics.

• Food Engineering Progress
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• v.14 no.3
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• pp.235-242
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• 2010

This study was to investigate the combined effect of enzyme and trehalose addition on the retrogradation rate and quality changes in a Korean traditional rice cake, Backsulgi. As for the enzyme, a commercial maltogenic amylase, Novamyl, was used. From texture profile analysis and sensory tests, the optimum enzyme content for the preparation of Backsulgi was determined to be 0.1%. Backsulgi was prepared with the fixed content of Novamyl (0.1%) and different ratios (5, 10, 15%) of trehalose, and physicochemical and sensory properties were examined for 3 days of storage at ${25^{\circ}C}$. As trehalose content increased, the water activity of Backsulgi decreased. In Hunter's color value, L- and a-values of trehalose-added samples were significantly lower than those of control. In texture profile analysis, hardness of Backsulgi decreased with trehalose content. During storage, a increase in hardness and a decrease in cohesiveness were typically observed for all samples. However, those changes were significantly reduced with trehalose content. The retardation of retrogradation with the enzyme and trehalose addition was confirmed using calculated Avrami rate and time constants. These results revealed that combined treatments of 0.1% Novamyl and 10% trehalose could produce Backsulgi of better sensory quality with retarded retrogradation compared to separated treatment.

• Korean Journal of Food Science and Technology
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• v.51 no.3
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• pp.221-226
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• 2019

This study investigated the optimal amount of shell powder (0.1, 0.2, 0.3, and 0.4%) to add to rice noodles containing 20% rice flour and compared their quality characteristics to those of wheat noodles containing a commercial alkaline reagent (added at 0.4%). As the amount of shell powder was increased, the L and b values (Hunter's color) increased. The pH, turbidity, and water absorption also increased as the amount of shell powder was increased. However, when the shell powder content exceeded 0.3%, the hardness, chewiness, springiness, and tension tended to decrease below acceptable levels. This might be because the shell powder inhibited network formation. The textural properties and pH value of rice noodles containing 0.2% shell powder were similar to those of the wheat noodles. This suggests that 0.2% shell powder may be the optimal amount to add to rice noodles when used as the alkaline reagent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.1
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• pp.65-71
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• 2007

Five different commercial chungkukjang powders (A$\sim$E) were compared based on their physicochemical, organoleptic and functional properties. The proximate composition of the five samples ranged from 6.07 to 8.54% in moisture, 15.31 to 27.07% in crude protein, 20.19 to 24.75% in crude lipid, 34.84 to 52.41% in carbohydrate, and 3.69 to 5.26% in ash. The pH of the samples ranged from 5.58 to 6.11, and Hunter's colors showed 70.01$\sim$77.22 for L value, 0.91$\sim$4.64 for a value and 23.72$\sim$31.00 for b value depending on the product. The microbial counts were 8.16$\sim$g.60 log CFU/g for aerobic bacteria, $\sim$4.16 log CFU/g for yeasts & molds, and 1.07$\sim$3.88 log CFU/g for coliforms. The contents of reducing sugars and amino-N were 1.89$\sim$2.41% and 2.83$\sim$7.31%, respectively. Free amino acids were mainly composed of glutamic acid, valine, leucine, phenylalanine, and lysine. The amounts of total phenolics and total flavonoids were 108$\sim$302 mg% and 2.73$\sim$9.41, respectively, with some variations in the products. However, the isoflavone contents, which were composed of genistein (63.26$\sim$217.16${\mu}g/g$), daidzein (58.24$\sim$166.65${\mu}g/g$), genistin (2.66$\sim$55.68${\mu}g/g$), and glycitein (12.26$\sim$17.82${\mu}g/g$), were apparently different per product. The sensory scores for color, smell, taste and overall preference for the five chungkukjang products, which were evaluated by panels in their 20's and 30's using 7-point scoring test, ranged from 3.20 to 4.05.