• Microbiology and Biotechnology Letters
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• v.9 no.4
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• pp.191-196
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• 1981

In order to utilize the Koryangju distillers' grain for the acetic acid fermentation, the extracting methods and effects of the extracts on the fermentations were investigated. The result obtained are as follows. 1. Cold extracting method by which the distillers grain is extracted with 3 times of water for 60 hours at room temperature was better than hot extracting method in terms of the fermentation rate and the quality of vinegar product. 2. Optimum conditions and some results of surface fermentation based on the medium added by the extracts are as follows, optimum amount of the extracts to be added to the medium is 20-30% of total media; acetic acid production rate at log phase was 0.16g/100$m\ell$, hr.; recovery was 91.17%; and the time of 40 hours was required for the completion of fermentation. 3. Organoleptic quality of the vinegar which is produced by adding the extracts was superior to two commercial products examined.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.4
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• pp.588-597
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• 2007

Low-fat ground pork patties, LFGPP (<10% total fat) formulated with 0.1, 0.2 and 0.3 percent sodium alginate (SA) were processed and compositional, processing and sensory characteristics were compared with control patties containing 20% fat. The moisture content of raw and cooked LFGPP were significantly (p<0.05) higher than control patties because of greater amount of added water in the formulation. The cooking yield, moisture and fat retention also increased linearly in different treatments of LFGPP. The dimensional parameters such as gain in height, decrease in diameter and shrinkage were significantly (p<0.05) lower in LFGPP in comparison to control. Amongst the sensory attributes, flavour showed a declining trend with the increase in concentration of SA in LFGPP. However, low-fat patties with 0.1% SA rated similar to high-fat control. The lipid profile revealed 49.78 and 43.22% decrease in total lipids and cholesterol content respectively, compared to control. The calorie content was reduced significantly (p<0.05) in LFGPP. The texture profile of LFGPP with 0.1% SA was similar to that of high-fat control. The LFGPP remained stable without any appreciable loss of physico-chemical, microbiological and organoleptic quality during refrigerated storage ($4{{\pm}}1^{\circ}C$) for 21 and 35 days in aerobic and vacuum packaging respectively.

• Journal of Dairy Science and Biotechnology
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• v.34 no.4
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• pp.271-278
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• 2016

The main purpose of milk heat-treatment is to improve milk safety for consumer by destroying foodborne pathogens. Secondly, heat-treatment of milk is to increase maintaining milk quality by inactivating spoilage microorganisms and enzymes. Pasteurization is defined by the International Dairy Federation (IDF, 1986) as a process applied with the aim of avoiding public health hazards arising from pathogens associated with milk, by heat treatment which is consistent with minimal chemical, physical and organoleptic changes in the product. Milk pasteurization were adjusted to $63{\sim}65^{\circ}C$ for 30 minutes (Low temperature long time, LTLT) or $72{\sim}75^{\circ}C$ for 15 seconds (High temperature short time, HTST) to inactivate the pathogens such as Mycobacterium bovis, the organism responsible for tuberculosis. Ultra-high temperature processing (UHT) sterilizes food by heating it above $135^{\circ}C$ ($275^{\circ}F$) - the temperature required to destroy the all microorganisms and spores in milk - for few seconds. The first LTLT system (batch pasteurization) was introduced in Germany in 1895 and in the USA in 1907. Then, HTST continuous processes were developed between 1920 and 1927. UHT milk was first developed in the 1960s and became generally available for consumption in the 1970s. At present, UHT is most commonly used in milk production.

• Preventive Nutrition and Food Science
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• v.8 no.2
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• pp.191-195
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• 2003

We investigated the effects of gamma irradiation on the microbiological, chemical and sensory qualities of bulgogi, a traditional Korean meat product. Gamma irradiation reduced the number of coliform bacteria and bacterial colonies counted in Salmonella-Shigella selective agar to a non-detectable level. Thermophillic microorganisms (mainly Bacillus spp.) in bolgogi refrigerated for 20 days were also significantly reduced by 3 log cycles by 2.5 to 7.5 kGy of irradiation, compared to the control. Electron donating ability and shear force of ready-to-cook bulgogi was not significantly affected by gamma irradiation. Irradiation increased the 2-thiobarbituric acid reactive substances (TBARS) value. The irradiated, raw, ready-to-cook bulgogi had significantly higher scores in color and appearance than those of non-irradiated controls from sensory evaluation. The overall acceptance of cooked bulgogi had higher scores in non-irradiated or 2.5 kGy-irradiated bulgogi than the 5.0- or 7.5-kGy irradiated counterparts. In conclusion, irradiation at 2.5 kGy is recommended as a method to improve shelf-life, safety, and to achieve acceptable quality of ready-to-cook bulgogi without any adverse changes in the sensory characteristics.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.407-415
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• 1993

Sesame seeds were roasted for 30, 60, 90, and 120 min at different temperatures (100, 200, and $300^{\circ}C$) and extracted to investigate an adequate condition for producing the high quality sesame oil. Sesame seeds roasted at $200^{\circ}C$ for 90 min gave the high yield of oil. The oil contained the low content of brownish-black precipitates and exhibited an excellent organoleptic quality when judged by descriptive sensory analysis. Thirty one volatile flavor compounds, which are the largest number of volatiles among the oil samples prepared, were identified from the oil sample. The oil contained relatively high concentrations of furfurals (sweet candy-like flavor) and pyrazines (roasted-like flavor), that are considered as good contributors to sesame seed oil flavor, and low concentations of aldehydes $(C5{\sim}C10)$ and ketones, which are considerd as bad contributors (oxidized fat-like and painty-like flavors). These results suggest that the roasting condition of $200^{\circ}C$ for 90 min was the best for the oil production in terms of the overall aroma and taste quality under the test conditions (Received July 13, 1993; accepted November 4, 1993).

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.224-230
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• 1999

The purpose of this study was to find out the optimal mixing ratio of green tea powder, sugar, and water for the preparation of Seolgiddeok through Response Surface Methodology based on the color, sensory, and texture test. The oganoleptic and textural properties of Seolgiddeok prepared with various concentrations of green tea powder (0% (control group), 0.5% (GT-0.5 group), 1% (GT-1.0 group), 1.5% (GT-1.5 group), 2% (GT-2.0 group)), and their quality changes during storage were also investigated. The optimal mixing ratio of green tea powder, sugar, and water for preparing the best quality Seolgiddeok was 1.0%, 12%, and 22%, respectively. The proximate composition of green tea powder was 21.70% of crude protein, 8.49% of crude lipid, 2.95% of reducing sugar, and 6.40% of ash. The contents of crude lipid, reducing sugar, and catechins in Seolgiddeok added with a green tea powder were increased with increasing the content of green tea powder. The hardness and gumminess of GT-1.0 group were the lowest among four groups, whereas GT-1.0 and GT-2.0 groups had the lowest cohesiveness. While the control group was the lowest in adhesiveness, the springness was not significantly different among all groups. GT-0.5 and GT-1.5 groups were the highest in sweet taste and colorfulness, respectively. However, GT-1.0 group had the best overall quality. Total microbial numbers, the acidity and pH in Seolgiddeok during storage were decreased with increasing green tea powder content, and especially those of GT-1.0 and GT-1.5 groups were relatively the lower than others. The “L” value (lightness) of the control group (no additives) was the highest among five groups, and the value was decreased with storage period, and especially GT-0.5 groups had the lowest brightness. The“a”value (reddness) of the control group was the highest, followed by GT-0.5, GT-1.0, GT-1.5, and GT- 2.0 group in order. The“b”value (yellowness) was increased with the increase of green tea powder content. Above results indicated that GT-1.0 group showed the best quality of Seolgiddeok through organoleptic and rheology tests.

• Korean Journal of Food Science and Technology
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• v.26 no.2
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• pp.167-171
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• 1994

With a view to improving microbiological quality of spinach powder which is currently used for convenience food production, comparative efficacy of ethylene oxide(EO) fumigation and gamma irradiation was investigated by determining microbial populations and physicochemical quality for treated samples. Spinach powder was contaminated with various microorganisms ranging from $10^{2}/g\;to\;10^{4}/g$, which composed of thermophiles, acid tolerant bacteria, fungi, coliforms, etc. Microorganisms contaminated were destroyed up to undetected levels by gamma irradiation at below 7 kGy. showing the radiosensitivity $D_{10}$ 2.93 kGy on total aerobic bacteria. Ethylene oxide fumigation, however. was found unsatisfactory for physicochemical quality as well as microbial decontamination of the sample. It has been generally observed that influence of optimum-dose range of irradiation on the physicochemical qualities was insignificant, which was proved in the organoleptic evaluations on the stored sample.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.482-489
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• 1996

Dried-red pepper, whole and powdered types, was subjected to a storage-study by investigation the effects of packaging methods (polycloth & polyethylene/polycloth, whole dried-red pepper; nylon/polyethylene-lam-inated film, red pepper powder), temperature (ambient, $5{\sim}10^{\circ}C$) and gamma irradiation doses (0-10 kGy). After 6 months storage in polyclith sack at ambient temperature, all whole dried-red pepper showed quality deterioration, such as weight change, insect infestation, discoloration and chemical changes, After 2 years storage in combined packaging with polyethylene/polycloth sack of 5-7.5 kGy irradiated whole dried-red pepper at ambient temperature, however, quality deterioration was not observed. Gamma-irradiated red pepper powder (7.5-10kGy) showed a good quality in hygienic, physicochemical and organoleptic evaluation after 2 years of storage at ambient temperature.

• Journal of the Korean Society of Food Culture
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• v.29 no.2
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• pp.195-204
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• 2014

This study was conducted to evaluate the quality characteristics and antioxidant activities of rice flour sponge cakes containing 0, 20, 30, 40, and 50% Helianthus tuberosus powder (HTP). As HTP content of sponge cake increased, the pH of sponge cake batter significantly decreased, whereas specific gravity significantly increased (p<0.05). Meanwhile, volume and symmetry indices of sponge cake were inversely proportional to HTP amount. Further, with higher HTP content in sponge cake, L and b values of crumbs significantly decreased (p<0.05), whereas a value significantly increased (p<0.05). L, a, and b values of crust significantly increased with higher HTP content. For texture characteristics, hardness, cohesiveness, gumminess, and chewiness of sponge cake significantly increased (p<0.05),whereas cohesiveness did not significantly change. In the sensory evaluation test, rice sponge cake prepared with 10% HTP showed the highest sensory scores in terms of color, flavor, taste, softness properties, and overall preference. The levels of total polyphenol compounds and DPPH radical scavenging activities of rice sponge cakes significantly increased with higher HTP contents (p<0.05). The results of this study suggest that rice sponge cake containing 10% HTP is the most appropriate for quality characteristics and sensory evaluation. This study also provides a way to increase the quality, texture characteristics, and organoleptic properties of sponge cake while reducing HTP content to less than 10% in order to satisfy consumer tastes.

• Journal of the Korean Society of Food Culture
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• v.4 no.4
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• pp.405-410
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• 1989

The sensory quality describing terms of Takju were surveyed by questionair and classified according to the sensory characteristics. The effects of thermal treatment for the pasteurization of Takju on the sensory quality were tested and statistically evaluated. The important sensory quality attributes of Takju were white, gray, and yellow for color, acidic and yeasty for smell, sour, astringent, bitter and sweet for taste and gritty, viscous and carbonated for mouthfeel. The organoleptic properties of grayness, yeasty and cooked smell, astringent and bitter taste and thickness increased, while sourness, sweetness, yellowness, grittiness and carbonated feel decreased by the pasteurization treatments, heating $82^{\circ}C$, $93^{\circ}C$ or $135^{\circ}C$ for 9 seconds. These changes coincided with the overall reductions in the preference scores of pasteurized Takju. The degree of sensory quality deterioration appeared to be affected to some extent by the heating temperature.