• Applied Biological Chemistry
• /
• v.51 no.3
• /
• pp.207-211
• /
• 2008

In order to understand the difference in rice eating quality, two rice varieties having different eating qualities were examined from the correlation between palatability score (Toyo value) and components of lipid in rice endosperm. We also analyzed the relationship between lipid properties and physicochemical characteristics of milled rice. Major fatty acids of milled rice starch-lipids, known to exist as inclusion complexes with amylose in starch granules, were palmitic (38.25% in Gopum and 39.75% in Palgong) and linoleic aicds (33.13% in Gopum and 31.93% in Palgong). In addition, the unsaturated fatty acid contents of rice endosperm showed a significant relationship with palatability. Plant sterols in two rice samples were identified, Gopumbyeo of good eating quality had high contents of squlaene and cycloartenol and similar contents of campesterol, stigmasterol and sitosterol. There were significant differences in pasting properties of rice flours and starches between the two cultivars. These results suggested that rice lipids impact on pasting properties after cooking, subsequently relating to palatability.

• Journal of Biosystems Engineering
• /
• v.39 no.4
• /
• pp.330-335
• /
• 2014

Purpose: This study was conducted for enhancing the performance of a conventional quick freezer by introducing the supercooling state, using a low-temperature coolant. Methods: In the present investigation, the supercooling process was executed prior to quick freezing for reducing the time by which the temperature passes the zone of maximum ice crystal formation. Every food has different nucleation points and hence, we used silicone oil as the coolant for supercooling for easy modification of temperature. Additionally, for quick freezing, we used liquid nitrogen spray. Results: Using the heat exchanger-type precooler with silicone oil, the temperature of the chamber was easily changed for enabling supercooling. Particularly, the results of the freezing test with garlic indicated that this system improved the hardness of garlic after it was thawed, compared to the conventional freezing method. Conclusions: Before quick freezing, if the food item is subjected to the supercooling state, the time from nucleation to the temperature reaching the frozen state ($-5^{\circ}C$, which is the maximum ice crystal formation zone) will be shorter than that incurred using quick freezing alone. The combination of the heat exchanger-type supercooler and liquid nitrogen sprayer is expected to serve as a promising technology for improving the physicochemical qualities of frozen foods.

• Food Science of Animal Resources
• /
• v.30 no.5
• /
• pp.780-786
• /
• 2010

This study compared the effects of autoclaving (AC; $121^{\circ}C$ for 15 min), gamma (GR), and electron beam irradiation (EB; 0-20 kGy) on the microbial, physicochemical, and sensory properties of ready-to-eat bulgogi during storage at $35^{\circ}C$ for 90 d. No viable cells were observed (p<0.05) upon AC, GR or EB at more than 15 kGy. However, adverse effects such as tenderization and deterioration of sensory properties were induced in bulgogi upon AC and high dose irradiation. Especially, the hardness and sensory qualities (texture and taste) of the AC-treated samples were extremely deteriorated (p<0.05). These results indicate that use of GR and EB (15 kGy) can ensure the microbial safety of bulgogi without compromising the hardness and sensory properties (texture, taste and flavor).

• Korean Journal of Food Science and Technology
• /
• v.20 no.3
• /
• pp.441-446
• /
• 1988

Alkaline treatment during preparation of anchovy extracts was studied for its changes in some of the physicochemical and sensory qualities. The dried anchovy was blended in 0-0.5N NaOH solutions and then incubated at $60^{\circ}C$ for 6 hours. After extraction the suspensions were neutralized and centrifuged. The results showed that the yields of solids and protein were increased by 3-5 fold of those of water extract as alkaline concentration and treatment time increased. The intrinsic viscosity showed little changes for the extracts prepared with 0-0.2N NaOH solution while the extracts prepared with over 0.3N NaOH resulted a initial small decrease followed by a rapid increase to the maximum point. The changes in color expressed as Hunter 'L', 'a' and 'b' values showed that the L value increased rapidly until 3 hours of treatment followed by a decrease, and 'a' and 'b' values were increased a little. The intensities of odor and taste were markedly increased by 2-3 fold for all of the descriptions investigated where clam-like odor and taste and sea complex odor were particularly significant.

• The Korean Journal of Food And Nutrition
• /
• v.14 no.5
• /
• pp.418-422
• /
• 2001

Physicochemical qualities of the different commercial red pepper powder purchased in the market were investigated. In proximate composition of red pepper powder, crude protein contents were not much different from 10.10% to 10.91% but sample Ds crude lipid was the lowest as 8.28% and Cs was the highest as 11.43%. The pH values of red pepper powder were not significantly different. The value of L, a and b of sample C were 46.667, 22.738 and 19.941 respectively but it showed lower ASTA color than sample A and had same tendency with capsanthin. The highest content of capsaicin was sample D as 59.93mg 1100g and sample B was the lowest as 25.87mg/100g. Water activity of the sample A, B, C and D were 0.584, 0.676, 0.526 and 0.568 respectively. Sample A, C and D showed safety against microorganisms but sample B was susceptible to the mold.

• Korean journal of food and cookery science
• /
• v.23 no.1 s.97
• /
• pp.41-49
• /
• 2007

The substitution effects of whey protein isolate(WPI) for egg in the preparation of sponge cake were determined by objective and subjective tests. Milk whey is drained from milk curd as a by-product of cheese manufacture. Whey protein is known as a good nutritional source and a functional material for many processed foods, especially baked goods. WPI contains above 90% whey protein. The specific gravity and viscosity of sponge cakes tend to be affected by WPI substitution. The cooking loss of sponge cakes with WPI substituted for egg(abbreviated as WPI cake) during oven baking was smaller than that made with egg(abbreviated as egg cake) and the specific loaf volume of WPI cake was larger than that of egg cake. The number of pores was highly increased and the size of pores was more uniformly and finely distributed in the cross section of WPI cake than those of egg cake, as observed by scanning electron microscopy(SEM). The hardness, gumminess and chewiness of WPI cake made with 10-20% WPI substitution were the lowest among all the tested cakes, including egg cake, thereby confirming the considerable improvement in their cake qualities. By the results of sensory evaluation, appearance, pore uniformity, softness, chewiness, moistness, flavor, mouth feeling, and overall acceptability of 10-20% WPI substitute cakes were evaluated as being significantly superior to those of all other cakes(p<0.05). These results support the better physicochemical characteristics and sensory evaluations of sponge cake prepared with 10-20% of WPI substitution for egg.

• Korean Journal of Food Science and Technology
• /
• v.20 no.4
• /
• pp.498-503
• /
• 1988

Rice and rice flour were stored at $13^{\circ}C$, room temperature$(17-28^{\circ}C)$ and $38^{\circ}C$ for six months and the changes in physicochemical and organoleptic qualities were investigated to determine the preservability. Fat acidity increased rapidly up to 60 days at room temperature and 45 days at $38^{\circ}C$ and thereafter it increased slowly. At $13^{\circ}C$, it increased constantly and slowly throughout the storage. In the changes of Hunter's color for the rice and rice flour, L-value was decreased, but ${\Delta}\;E-Value$ was increased. In amylograph properties, initial pasting temperature, maximum viscosity and breakdown were all increased. Quality of stored rice was a little superior to rice flour, but there were not significantly different among them.

• Korean journal of food and cookery science
• /
• v.25 no.6
• /
• pp.739-746
• /
• 2009

The quality characteristics and antioxidant activities of Yanggeng prepared with different amounts of fermented and aged garlic paste(0, 10, 20 or 30%) were determined. The pH of fermented and aged garlic Yanggeng decreased according to the amount of added fermented and aged garlic paste, whereas the acidity increased. In addition, the lightness of fermented and aged garlic Yanggeng decreased according to the amount of added fermented and aged garlic paste. In the texture analysis, hardness, cohesiveness and springiness of fermented and aged garlic Yanggeng were lower than those of the control. Total phenol content was highest in 30 % fermented and aged garlic Yanggeng. The antioxidant activities of fermented and aged garlic Yanggeng increased according to the amount of added fermented and aged garlic paste. The IC50 value of 30% fermented and aged garlic Yanggeng was 45.1 mg/g for DPPH and 29.6 mg/g for hydroxyl radical. The results of the sensory test showed that Yanggeng with 20% fermented and aged garlic paste had the highest score in appearance, overall preference and texture. Based on these results, it was suggested that the addition of 20% fermented and aged garlic to Yanggeng was appropriate for good food qualities both in terms of the physicochemical and antioxidative activities.

• Korean journal of food and cookery science
• /
• v.33 no.1
• /
• pp.45-53
• /
• 2017

Purpose: Physicochemical and microbiological qualities were investigated to compare quality characteristics of traditional with commercial soy sauce (Ganjang). Methods: Nineteen traditional products were collected from six provinces and three commercial products were purchased in domestic markets. The proximate composition, inorganic substance contents, viable bacteria, and chromaticity of the soy sauces were measured. Results: Although concentrations of crude fat and protein were not significantly different between traditional and commercial Ganjang, the moisture concentration of commercial soy sauce was significantly higher than in traditional Ganjang (p<0.05). However, the amount of ash in commercial soy sauce was significantly lower than in traditional Ganjang (p<0.05). Total nitrogen concentrations of traditional and commercial Ganjang were 0.50-1.59% and 0.86-1.26%, respectively. Concentrations of Na, Mg, K, Ca, Li, B, Fe, and Sr in traditional Ganjang were significantly higher than in the commercial products (p<0.05). The number of total bacteria in traditional and commercial Ganjang were $3.3{\times}10^1-6.4{\times}10^7CFU/mL$ and $5.5{\times}10^1-2.0{\times}10^3CFU/mL$, respectively. Bacillus cereus were below 10,000 CFU/mL in all samples, and Staphylococcus aureus was not detected. Fungi was not detected in 13 samples of traditional Ganjang and the three samples of commercial soy sauce. Although lightness, redness, and yellowness were not significantly different among the Ganjang, G10 was had the highest values (p<0.05). Conclusion: This research provided information about the quality characteristics of traditional and commercial Ganjang.

• Journal of the East Asian Society of Dietary Life
• /
• v.14 no.6
• /
• pp.598-607
• /
• 2004

This study was conducted to examine the sensory characteristics and the contents of proximate composition and the free sugars of the Demi-glace with varying quantity of Omija extracts added. First, the qualities of Demi-glace sauces with varying quantity of Omija extracts added are as follows: (1) Proximate composition: The moisture content was 66.10～73.50%, and crude ash content was 1.59～1.89%. As the Omija extracts added increased, moisture content increased, whereas crude ash content decreased. The crude protein content was 6.12～7.95%. Among them, the one with the 2% Omija added showed the highest level of the crude protein. (2) Free sugars contents: In terms of total sugar contents, the control showed 1.32% and Omija sauces showed 1.44～1.55%. Major free sugars analyzed in the order of fructose, oligosaccharide, glucose and sucrose. Second, the results of sensory evaluation of Demi-glace sauces with the different levels of Omija added are as follows: (1) The preference of Demi-glace sauces according to occupation: Students and Cooks liked the one with the 2% Omija added in terms of color, flavor, taste, texture and overall acceptability. Cooks showed higher preference than students. (2) The preference of 5 tastes: It was found that Demi-glace sauce with the 2% Omija added was the best. The one with the 2% Omija added was suitable in terms of sweet taste and bitter taste and the one with the 3% Omija added was desirable for hot taste and saline taste. In terms of sour taste, the one with 1% Omija added was regarded as the most desirable one. (3) The preference for authentic tastes for Demi-glace sauce: In terms of simple taste, females showed higher preference than males. Demi-glace sauce with the 2% Omija added was found to be the best for savory taste, flavor enhancer taste, simple taste, after taste and overall acceptability. The one with the 1 % Omija added was regarded as the best for soft taste.