• Food Science of Animal Resources
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• v.40 no.6
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• pp.1033-1043
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• 2020

This study investigated the impacts of gelatin hydrolysate addition on the technological properties and lipid oxidation stability of cooked sausage. Gelatin hydrolysate was prepared from pork and duck skin gelatin, through stepwise hydrolysis using collagenase and pepsin. The cooked sausages were formulated without gelatin (control) or with 1% pork skin gelatin, 1% duck skin gelatin, 1% pork skin gelatin hydrolysate, and 1% duck skin gelatin hydrolysate. The pH, color characteristics, protein solubility, cooking loss, and textural properties of cooked sausages were evaluated, and the 2-thiobarbituric acid reactive substances (TBARS) value was measured weekly to determine lipid oxidation stability during 4 wk of refrigerated storage. Enzymatic hydrolysis of gelatin decreased protein content and CIE L* but increased redness and yellowness (p<0.05). When 1% gelatin or gelatin hydrolysate was incorporated in cooked sausage, however, little to no impacts on pH value, moisture content, protein content, color characteristics, protein solubility, and cooking loss were found (p>0.05). The addition of 1% duck skin gelatin hydrolysate increased the cohesiveness and chewiness of cooked sausages. The inclusion of 1% duck skin gelatin accelerated lipid oxidation of cooked sausages during refrigerated storage (p<0.05), whereas duck skin gelatin hydrolysate caused a lower TBARS value in cooked sausage compared to duck skin gelatin. The results show comparable effects of gelatin and gelatin hydrolysate addition on the technological properties of cooked sausages; however, the oxidative stability of raw materials for gelatin extraction should be evaluated clearly in further studies.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.355-363
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• 1999

The experiments were carried out to elucidate the varietal variation of retrogradation in aged cooked rice and its association with some physicochemical properties of milled rice. The fifteen rice materials were selected from forty-three low-amylose japonica and Tongil-type rice cultivars based on palatability and retrogradation of cooked rice stratified by preliminary sensory evaluation of warm and cooled cooked rice. One japonica glutinous rice variety was included for comparison of retrogradation of cooked rice. The $\alpha$-amylase-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The desirable checking time for evaluating the varietal difference in deterioration of aged cooked rice was four hours after storing in room temperature and two hours after preserving in refrigerator based on the largest coefficients of variations in degree of retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, showed the relatively fast deterioration of cooked rice. The retrogadation index represented by the percentage of retrogradation difference between warm and cooled cooked rice to original estimates of warm cooked rice was significantly affected by the degree of retrogradation of cooled cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogradation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked nce. The varietal difference in retrogradation of cooked rice can be effectively classified by scatter diagram on the plane of upper two principal components based on some retrogradation properties of cooked rice. The deteriorated structural change in cooled cooked rice by observing through the scanning electron microscope was more conspicuous in the fastly retrograded cooked rice than in the slower one.

• Culinary science and hospitality research
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• v.18 no.1
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• pp.54-64
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• 2012

The purpose of this study is to develop $Sulgidduk$ which meets the consumers' taste by using cooked purple sweet potato. The samples of $Sulgidduk$ were prepared with different ratios of cooked purple sweet potato(0, 10, 20, 30, 40%) and analyzed for moisture content, Hunter's color value and texture characteristics and sensory evaluation. The moisture contents of the samples ranged 40.83% to 44.91% The L-value and b-value decreased, while a-value increased, with increasing amounts of cooked purple sweet potato. In the mechanical evaluation of physical properties, hardness, adhesiveness, springiness, gumminess and cohesiveness showed no significant difference with the increasing amount of cooked purple sweet potato. However, chewiness decreased significantly with the increasing amount of cooked purple sweet potato. Based on the quantitative descriptive sensory evaluations on $Sulgidduk$ samples, purple color, sweet potato flavor and taste, sweetness, and moistness significantly increased, while hardness decreased significantly with the increasing amount of cooked purple sweet potato. $Sulgidduk$ added 40% cooked purple sweet potato showed the highest in overall acceptability and the slowest hardening in the textural changes during storage.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.885-890
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• 1995

Ten Korean rices were cooked at various moisture contents($57.5{\sim}69.5%$) and the sensory characteristics including appearance, flavor, texture and overall desirability were evaluated. The clumpiness, firmness and moistness of the cooked rice were significantly affected by moisture content in all samples. The optimum moisture content of the cooked rice was 66.5%. The rices cooked at optimum moisture content showed differences among varieties in off-odor, glossiness and color and no differences in other sensory characteristics(p<0.05).

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.45-53
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• 1999

Physicochemical and sensory characteristics of cooked rice during warm-keeping with different temperature $(70,\;75,\;80^{\circ}C)$ and period (0, 6, 12, 24, 48 hr) were investigated. As the storage temperature increased, sweet flavor, glossiness, moistness, taste and moisture content decreased but off-flavor, color and sensory and texturometric hardness increased. This trend was significant with storage period. As the storage time and temperature increased, yellowness(b) measured by Hunter color difference meter increased while lightness(L) and whiteness decreased. Degree of retrogradation of cooked rice during storage increased, particularly did in cooked rice stored at $80^{\circ}C$. Cooked rice stored at 70 and $75^{\circ}C$, 6 hr had the least changes in flavor and appearance but more changes in them longer storage time. Cooked rice stored at $80^{\circ}C$ had rapid changes in flavor, appearance and texture at initial state of storage. These results showed that the changes in moisture content of cooked rice stored at various conditions had the most important effect upon sensory characteristics of cooked rice.

• Journal of Applied Biological Chemistry
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• v.53 no.4
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• pp.219-224
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• 2010

This study was conducted to investigate the effect of medical herbs extracts on physicochemical characteristics of cooked rice. Three types (CLP 1, CLP 2, CLP 3) of extracts were prepared using 11 medicinal herbs, respectively. Polished rice was cooked with different concentration of medicinal herbs extracts by electric cooker. The moisture contents in cooked rice were decreased by increased concentration of herbs extracts, while total polyphenol contents were significantly increased. DPPH radical scavenging activities of cooked rice obviously were increased as herb extracts level increased. The consistency and setback value of the rice flour was reduced at all of the extracts, while breakdown and initial pasting temperature was increased. Color of cooked rice was shown different comparing to the control. However, the hardness, adhesiveness, springiness, cohesiveness and gumminess of cooked rice was increased depending on the concentration of extracts. These results showed that medicinal herbs extracts, which can benefit human health, is inducing the changes of physicochemical characteristics of cooked rice.

• Korean journal of food and cookery science
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• v.10 no.4
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• pp.351-356
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• 1994

Comparisions were made for cooking times, internal temperatures, thiamin contents and textural properties of various portion weights of egg mixture cooked in a microwave oven at high and/or low power levels and in a conventional double boiler. The mean internal temperatures of conventionally cooked egg mixtures were 76.4~80.7$^{\circ}C$. When cooking was made by steaming, the mean internal temperature were comparable among samples. With the microwave cooking, the range of mean temperature was 83.8~96.4$^{\circ}C$, and they were significantly higher than the conventionally cooked egg mixtures. The hardness determination was conducted using universal testing machine and a taste panel. Samples cooked with steam or with larger portion weight had softer texture than samples cooked by microwaves or smaller amount, respectively. Mean internal temperature was significantly(r=0.99, p<0.05) correlated with mechanical hardness determination. Statistical analyses indicated no significant difference in the thiamin content among various treatments.

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.142-149
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• 1999

Moisture absorption rate of rice according to the soaking time was higher at $25^{\circ}C$ than 4$^{\circ}C$ and the op-timum soaking time was 1hr at $25^{\circ}C$. When the ratios of added water for rice cooking were 1.3 in an elec-tric cooker and pressure cooker and 1.7 in an Dookbaeki sensory an mechanically evaluation of cooked rice were highly evaluated. The total number of peak on gas chromatography profile were 89 in an press-ure cooker 56 in an electric cooker and 83 in an Dookbaeki and major volatile compounds of cooked rice were aliphatic hydrocarbons cyclic hydrocarbons aromatic hydrocarbons aldehydes alcohols ketones and thiourea. Furan that is in sweety was not detected in volatile components of cooked rice of electric cooker.

• Journal of the Korean Society of Food Culture
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• v.20 no.2
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• pp.253-260
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• 2005

This study was conducted to investigate performance of methods for cooking and thawing frozen cooked rice to retard retro-gradation of cooked rice. For this research, That was executed rice's physicochemical and sensory characteristics test through the way of boiling rice or thawing, and found out best way for retro-gradation and taste. This study showed the rice cooked by pressure rice pot has less dehydration during freezing and thawing, and thawed rice by micro wave has less dehydration. Repetition of freezing and thawing resulted increasing of hardness and chewiness, and decreasing of adhesiveness and cohesiveness. The rice cooked by convotherm oven or pressure rice pot has less increased hardness while freezing and thawing. Adhesiveness was superior when rice was cooked by pressure rice pot. The rice thawed by microwave had more hardness than thawed in room temperature.

• Korean journal of food and cookery science
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• v.10 no.4
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• pp.346-350
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• 1994

This investigation was undertaken for the purpose of studying the effect of the addition of the powder(0, 1, 2, 3%)from fruit of paper mulberry(Broussonetia Kazinoki SieboId) on the hardness, cohesiveness, elasticity, gumminess, chewiness, cooking loss and sensory characteristics of cooked ground beef with or without soysauce. The results obtained were summerized as follows; Hardness, gumminess, chewiness, and cooking loss were decreased by increasing the percent of adding the powder from the fruit of paper mulberry. As a result of sensory evaluation for cooked ground beef, sample with powder from the fruit of paper mulberry showed the higher scores in most of the characteristics. And cooked ground beef added the powder from the fruit of paper mulberry with soysauce showed the higher decreasing rate of hardness than those of without soysauce.