• Food Engineering Progress
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• v.15 no.4
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• pp.338-345
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• 2011

The pH, acidity, protein, color, reducing sugar, total sugar, alcohol and organoleptic characteristics of Takju containing 100% short grain rice (100 S), 100% long grain rice (100 L), 50 S+50% puffed rice powder (50 P) and 50 L+50 P were examined. After a drastic decrease during the initial stage of fermentation, the pH gradually increased except 100 L. Protein peaked at day 1 and decreased. A higher protein was noticed in puffed samples than in rice samples (p < 0.05). The Hunter "L" value decreased after a rise during the beginning of fermentation. Puffed samples showed higher reducing sugar than rice at day 0. Total sugar was similar to reducing sugar. A drastic increase in alcohol concentration was detected at day 2. Higher alcohol was observed in short grain than long grain and also in puffed samples than in rice (p < 0.05). A significant difference between 100 S and 100 L was observed in a sensory evaluation (p < 0.01); while no preference was detected.

• 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.

• Korean Journal of Food Science and Technology
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• v.52 no.6
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• pp.632-640
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• 2020

In this study, we produced macarons by adding white bean powder at various proportions (0, 25, 50, 75, and 100%). The macarons in the 100% additive group had the highest moisture content, smallest volume, highest weight, and highest sugar and reducing sugar content. The macarons in the 50% additive group had the highest spread factor.Furthermore, their pH and acidity demonstrated the greatest air bubble stability. In the Hunter color system, by adding white bean powder, the L value gradually decreased, whereas the a and b values gradually increased. The hardness, gumminess, and chewiness decreased with the addition of white beans. Flavonoids and total phenolic compounds, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, and superoxide dismutase (SOD)-like activity were the highest at 100%. Additionally, their overall acceptability was the highest at 50%. These results suggested that the use of white bean powder to produce macarons have numerous advantages.

• Journal of the Korean Society of Food Culture
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• v.22 no.4
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• pp.468-474
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• 2007

Physicochemical and sensory characteristics of cookies with various levels of resistant starch were investigated in this study. Dough pH of 30% substituted sample group had significantly the highest value than that of all(p<0.05). Water contents of Dough were decreased with increased levels of the resistant starch in cookie preparation. The spreadability was increased as the addition levels of the resistant starch were increased. The Hunter L and a values of 30% substituted sample group had the highest values of all(p<0.05). Results of sensory characteristics of 30% substituted sample group showed significantly the lower values in hardness and crack than those in the other groups at p<0.05. Acceptance tests of cookies with 10 and 20% substituted sample groups showed higher values in savory flavor and overall acceptability than those of others.

• Food Science and Preservation
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• v.22 no.2
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• pp.174-181
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• 2015

This study investigated the physicochemical properties of three different types of rice flour prepared via dry and wet milling. The powder, soft, and hard-types of rice flour were Suwon No. 542, Suwon No. 541, and Unbong No. 30, respectively. The analysis of the proximate compositions of the different types of rice flour showed that their moisture content was 7.03~7.99%, their crude protein was 7.94~8.35%, their crude lipid was 0.71~1.49% and their crude ash was 0.25~0.82%. For the Hunter's color values, the L value was highest in the wet-milled rice flour, the a value was highest in the dry-milled rice flour, and the b value was highest in the dry-milled rice flour. All the samples showed distinctive rice starch particles in the particle analysis using scanning electron microscope. The dry-milled rice flour showed the greatest amount of irregular particles and the coarsest texture. The water absorption and water solubility indices were higher in the wet-milled soft- and hard-type rice flour. The crystallinities of the samples by X-ray diffractography were all A-type, but the crystallinity of the dry-milled hard-type rice flour was higher in diffraction degree. For the amylogram properties, the wet-milled soft-type rice flour showed the highest maximum viscosity, breakdown and setback. In the meanwhile, the dry-milled soft-type rice flour showed the highest initial pasting temperature, onset, peak, and end temperatures despite of the reverse enthalpy.

• Korean journal of food and cookery science
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• v.12 no.4
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• pp.547-556
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• 1996

The purpose of this study was to invesitage the optimum cooking method, which ingridients mixing ratio and decortication of white and black sesame gruels, were examined by sensory and mechanical tests. As the results of sensory evaluation for the decortication white and black sesame gruels with the levels of 50, 100, 150, and 200％ sesame per rice l00ｇ, the flavor, nutty taste, and the overall preference were increased with the increase of sesame add. The gruel which made with decorticated sesame roafting for 7 minutes was proferable. The gruels 150% decorticated white and black sesame roasted 7 min had better overall preference. In the mechanical measurement for the white sesame gruels, L value tended to be decreased, while ‘a' and ‘b' values as well as viscosity tented to be increased as the sesame ratio and roasting time increased. In black sesame gruels, L value tended to be decreased, while ‘a' and ‘b' values as well as viscosity tended to be increased when sesame ratio was increased. In correlation between sensory evaluation and mechanical measurement of the white and black sesame gruels, color, flavor, nutty taste of sensory evaluation were correlated with the mechanical measurement. The optimal material mixing ratio for gruels was rice 100 g, white and black sesame 150 g, and water 1075 g.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.11
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• pp.1409-1416
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• 2007

Seven selected commercial pure or refined olive oils were obtained from the market, and their physicochemical properties and volatile characterizations were investigated. Fatty acid profiles of the analyzed olive oils showed oleic $(61.2{\sim}74.7mole%)$, palmitic $(10.2{\sim}16.8mole%)$, linoleic $(9.4{\sim}18.0mole%)$, stearic $(1.9{\sim}3.0mole%)$, palmitoleic $(0.7{\sim}2.4mole%)$ and linolenic acid $(0.5{\sim}0.9mole%)$. According to Hunter#s color measurement, pure or refined olive oils showed $L^*$ value of $92.2{\sim}99.0$, $a^*$ value of $-22.2{\sim}-3.2$, and $b^*$ value of $18.5{\sim}55.0$. Their total phenol contents ranged from 1.9 to $13.3mg/100g$ while ${\alpha}-tocopherol$ content showed $7.91{\sim}13.88mg/100g$. Oxidation stability of the pure or refined olive oils were observed by Rancimat. The induction period ranged from 17.37 to 34.72 hr while their POV were $6.83{\sim}20.31meq/kg$ oil. Electronic nose and gas chromatograph-mass spectrometry with head-space solid phase microextraction were applied to identify and discriminate the volatile compounds and flavors in pure or refined olive oils, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.12
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• pp.1632-1639
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• 2008

The antioxidant activities and quality characteristics of jam prepared with black garlic were evaluated. Fructo-oligosaccharide or maltitol syrup was replaced with sucrose: control (sucrose), fructo-oligosaccharide (FTO), FTOM (sucrose 50%＋FTO 50%), maltitol syrup (MT) and MTM (sucrose 50%+MT 50%). The endpoint of jam preparation was determined to reach $64^{\circ}Brix$ of sweetness. There were significant differences in moisture content among the treatments, whereas acidity among treatments was not different. Reducing sugar content and viscosity were the highest in FTO (0.144%, 126,800 cP), whereas the lowest in control (0.074%, 101,600 cP). Lightness (L value), redness (a value) and yellowness (b value) of Hunter color system were the highest in FTO compared to the others. Hardness and springiness of textural properties were the highest in FTO. Antioxidant activities were the highest in FTO with the lowest $IC_{50}$ values (42.3 mg/g for DPPH and 22.4 mg/g for hydroxyl radical scavenging activities). Total phenol content was highest in FTO among treatments. The overall acceptance score of black garlic jam containing FTO showed the highest score among treatments. Based on these results, it was suggested that fructo-oligosaccharide was appropriate for good qualities both in physicochemical and antioxidative activities of black garlic jam.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1826-1831
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• 2010

This study was carried out to examine the changes of the quality feature and antioxidant activity of grape by-products. This experiment was to arrange the basic data for developing a functional material using grape by-products which were useless resources. Hot-air and freeze drying were followed by the gamma irradiation of 1~20 kGy. Hunter's color value, in case of hot-air drying, showed the highest L and a value in the 3 kGy, and it decreased according to the increase of the exposure dose. In the case of fre ze drying it showed the highest L and b value at the highest exposure, 20 kGy. It was considered that the breakdown of the pigment through high temperature processing was launched and the influence according to the gamma irradiation was not shown. The gamma irradiation of 3 kGy appeared to have a good influence on the color of the grape by-products which went through hot-air drying. The contents of the total phenolic compounds, in case of hot-air drying, showed the highest total polyphenol contents in the 3 kGy irradiation and it decreased according to the increase of the exposure dose; in contrast, the higher phenolic contents showed in the irradiated group than in the control. In case of freeze drying, the highest phenolic contents appeared in the control but 3 kGy showed the highest one in the irradiated group. Results of radical scavenging activity using DPPH and ABTS indicated that 3 kGy showed the highest radical scavenging activity in hot-air and freeze drying. Therefore, it was found that gamma irradiation of 3 kGy could improve the color and antioxidant activity of grape by-products, but an antioxidant activity of grape by-product due to the gamma irradiation was a little affected in the aspects of by-product utilization.