• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.1
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• pp.109-114
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• 1998

For the purpose of improving quality of defrosted-frozen chicken leg, beef and yellow corvina, the effects of height(0mm : H0, 5mm : H5, 10mm : H10, 15mm ; H15) for microwave defrosting on their physicochemical properties were investigated. In frozen chicken leg, color values were not significant different between each treatment while H10 and H15 had the highest score on appearance. Hardness of defrosted chicken leg was increased as height increased. In frozen beef, temperature of beef after defrosting increased as hight increase and H10 had the highest appearance score. In frozen yellow corvina, H10 had the highest hardness and appearance scores. Physicochemical properties of color, texture and appearance of microwave-defrosted frozen food were changed by height within microwave oven.

• Environmental Engineering Research
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• v.10 no.2
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• pp.54-61
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• 2005

Liquid-phase catalytic degradation of waste high-density polyethylene (HDPE) over ZSM-5 (powder type (PW)) and ZSM-5+binder (granule type (GR)) has been investigated with a stirred semi-batch operation at 400°C. Two ZSM-5 catalysts with a different crystal size were synthesized and also each ZSM-5 (25%) Catalyst was mixed with a same binder (kaolin: silica sol: alumina = 55%:10%:10%). The performance of prepared catalysts that has different physicochemical properties was discussed with the cumulative amount distribution, molecular weight distribution and also paraffin, olefin, naphthene and aromatic (PONA) distribution in liquid product. These liquid product quality and distributions were changed depending on the physicochemical properties of the catalyst. Moreover, the characteristic of ZSM-5 in the catalyst was strongly influenced on the activity and PONA distribution in liquid product.

• Journal of the Korean Society of Tobacco Science
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• v.23 no.1
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• pp.12-18
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• 2001

This study was conducted to investigate the effect of tobacco curing on far infrared light on the quality of flue-cured tobacco leaves. Physicochemical characteristics such as alkaloid, total sugar, total nitrogen, starch, total phenolic compounds, browning degrees, and color differences, in cured tobacco leaves were compared between hot air and far infrared curing methods. There was no significant difference in sugar/nicotine ratio and nitrogen number between the curing methods, while the contents of ether extract and filling capacity were increase by far infrared curing. Therefore, it was expected that far infrared curing might be effective for high aroma and physical properties of the cured tobacco leaves.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1221-1227
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• 1997

To measure nutritional components and physical quality of Wanja-jeon(Korean pan fried meat balls)was investigated during storage in a simulated hospital cook/chill foodservice system. The Wanja-jeon was cooked and stored for 4 weeks in chill conditions of 2 and 7$^{\circ}C$ and then reheated in the microwave oven. Moisture, protein, and fat contents were decreased little during 4 weeks storage at 2 and 7$^{\circ}C$. Total unsaturated fatty acids(TUFA) and polyunsaturated fatty acids(PUFA) increased slightly at 7$^{\circ}C$ storage. Total free amino acid contents were reduced after 4 weeks of storage, while total amino acids were affected little during chilled storage. However, volatile basic nitrogen(VBN) increased during the 4 weeks storage from 11.2mg%, immediately after cooking, to 14.1~14.2mg%. After reheating, thiobarbituric acid(TBA) value increased more significantly to 0.19 and 0.20.

• Korean Journal of Food Science and Technology
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• v.53 no.1
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• pp.63-71
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• 2021

In this study, a comparative analysis was carried out between the 'Beta Tiny' and 'TY Nonari' cherry tomato cultivars harvested at the pink and red stages. Samples of the red stage were stored at room temperature for 9 days, during which physicochemical qualities, antioxidant compounds, and activities were measured. As cherry tomato ripening and storage progressed, firmness was reduced, whereas the lycopene content increased. Total phenolic content and antioxidant activity showed no significant changes as ripening and storage progressed; however, total flavonoid content of 'Beta Tiny' showed a significant increase (p<0.05). The main polyphenols in the two cultivars were identified as chlorogenic acid, rutin, and (-)-epigallocatechin gallate, among which chlorogenic acid showed a significant decrease (p<0.05) as ripening and storage progressed. A strong correlation was found between total phenolic and flavonoid content (R=0.744), and ABTS radical scavenging activity (R=0.975). Additionally, a negative correlation was shown by lycopene and chlorogenic acid (R= -0.934).

• Journal of Venture Innovation
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• v.1 no.2
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• pp.123-139
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• 2018

The research and the experiments were on physicochemical characteristics of Makgeolli based on input timing of Nuruk in the brewing processes, i.e., making mitsul with step-1/step-2 mashing, and making Takju with step-3 mashing, to establish the optimal conditions required for Makgeolli by checking the change of physicochemical characteristics and by inspecting culture characteristics based on input timing of Nuruk. When testing the physicochemical characteristics of mitsul(step-1/step-2), pH and acidity were reduced drastically on Day 1 of culture with step-1 mashing and the trend continued until Day 2 of culture, while there was no large change since then. In the sensory test, the aroma was the highest in M3 at 4.47, the acerbic taste was the highest in M3 at 3.65, the sweet taste was the highest in M1 at 3.88, and the feel in the mouth was the highest in M1 at 3.59. Overall preference encompassing aroma and taste was the highest in M3 at 3.71.

• Korean journal of food and cookery science
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• v.27 no.1
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• pp.85-99
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• 2011

Grinding is an indispensible step in preparation of espresso coffee. The purpose of this study was to evaluate physicochemical and sensory characteristics of espresso according to the grinding grades of coffee beans. Specifically, physicochemical characteristics according to the grinding grades of coffee beans were tested based on foam index, persistence of foam, total solids, concentration, extraction yield, pH, viscosity, total soluble solid content and density. With regard to sensory characteristics, QDA were carried out by 10 trained panels. Persistence of foam, total solids, concentration, extraction, pH and viscosity in physicochemical test showed significant differences among the three categories of the samples. In other words, the finer the size of particles was, the higher value was, at the p=0.001 value. Meanwhile, the value of foam index and total soluble solid content to the grinding grades was the highest in 'fine', at the p=0.001 value. Tiger-skin effect in crema, an important attribute for excellent espresso coffee, was perceived by all of the panels in 'fine'. Also, intensity of flavor was perceived as to the strongest in 'fine'. Moreover, 'fine' had the sweetness to balance the acids and bitters. In conclusion, according to the grinding grades, it was identified that there were differences in the physicochemical and sensory characteristics. Furthermore, when the size of particles was 'fine', it brought to the most positive result.

• Food Science of Animal Resources
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• v.34 no.4
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• pp.457-463
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• 2014

The effects of feeding of diets based on roughage supplemented with concentrate on the carcass and meat quality attributes of Korean black goats were investigated. The 40 male goats at 5 mon age were divided into four treatment groups; T1 (1.5%), T2 (2.0%), T3 (2.5%) and T4 (ad libitum) feeding of concentrate with ad libitum rice straw. Forty bucks at the end of the feeding were fasted for 12 h before slaughter and were then slaughtered. For carcass measurement, cold buck carcasses were examined after 24 h of chilling at $5^{\circ}C$. The carcasses were chilled in refrigerator at $2{\pm}2^{\circ}C$ for 24 h, then the longissimus dorsi muscle was removed from the carcasses. The samples were separately vacuum packaged, frozen and stored at $-20^{\circ}C$ for up to 1 mon, prior to physicochemical evaluations. Carcass yields were greatly affected by rate of concentrate feeding. T4 showed the heaviest live and carcass weights and the highest dressing and fat percentages (p<0.05). The moisture contents were lower in T4 compared with other treatments, while the crude protein and fat contents were higher (p<0.05). mono-unsaturated fatty acid in T4 was significantly higher than others, which showed the highest percentages of oleic acid (C18:1). For the sensory test, T4 was tenderer and produced better flavor scores than others. Increasing the level of concentrate in the diet resulted in an improvement in growth performance, and carcass and physicochemical characteristics of goat meats.

• Korean journal of food and cookery science
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• v.32 no.4
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• pp.524-530
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• 2016

Purpose: The properties of starch and starch gel prepared from a newly inbred sweet potato, Daeyumi were compared to the properties of starch and starch gel prepared from Sinyulmi which is a well known mealy type sweet potato. Methods: The starch was isolated by using the alkaline steeping method. Physicochemical, pasting, and thermal properties, and crystallinity were measured. The texture properties of starch gel (10%, w/w) were examined. Results: The amylose contents of Daeyumi and Sinyulmi starches were 25.57% and 22.59%, respectively. The initial pasting temperature of Daeyumi starch was significantly higher than that of Sinyulmi starch (p<0.05), but other paste viscosities were not different. The peak and conclusion temperatures of Daeyumi starch were higher than those of Sinyulmi starch by differential scanning calorimetry. The shape of Daeyumi starch gel was more clear and rigid than the shape of Sinyulmi starch gel. The surface and the upper side of Daeyumi starch gel were smoother than the surface and the upper side of Sinyulmi starch gel. Hardness and gumminess were higher in Daeyumi starch gel than in Sinyulmi starch gel. The crystallinity types of Daeyumi and Sinyulmi starches were $C_b$ and A types, respectively, but starch gels showed an amorphous type. Conclusion: Therefore, it is suggested that Daeyumi starch would have better physicochemical properties and higher quality of starch gel than Sinyulmi starch.

• Food Science of Animal Resources
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• v.32 no.2
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• pp.174-183
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• 2012

The effects of dietary fiber extracted from pumpkin (pumpkin fiber) on physicochemical properties, textural properties, and sensory characteristics of chicken frankfurters were investigated. Chicken frankfurter was supplemented with pumpkin fiber at levels of 0, 1, 2, 3, and 4%. Adding different levels of pumpkin fiber affected the proximate composition of the chicken frankfurters (p<0.05), except for protein content. In addition of different levels of pumpkin fiber influenced the physicochemical and textural properties of the chicken frankfurters (p<0.05). The yellowness, viscosity, and hardness were higher in chicken frankfurters samples containing pumpkin fiber than those in the control (p<0.05). The results showed that chicken frankfurter samples with higher pumpkin fiber levels had lower lightness values (p<0.05), as well as less cooking loss, emulsion stability, and lower color scores (p<0.05) compared to those control without pumpkin fiber treatment. The chicken frankfurters with 2% and 3% pumpkin fiber had higher overall acceptability than that of the control (p<0.05). The results show that adding pumpkin fiber produced acceptable chicken frankfurters and improved their quality characteristics.