• Food Science and Preservation
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• v.23 no.7
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• pp.1058-1064
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• 2016

This study investigated the correlation between physicochemical (color, soluble solids content (SSC), pH, titratable acidity (TA), and firmness) and sensory (appearance, taste, odor, and texture) characteristics of environment-friendly 'Campbell early' grapes to identify quality indices. For analysis, samples of similar-sized grapes were collected from five orchards. The results showed that the physicochemical characteristics of CIE $L^*$, CIE $a^*/b^*$, SSC, pH, TA, and firmness and the sensorial characteristics of color intensity, freshness of stem, odor, sourness, sweetness, and elasticity were different among groups. Correlation analysis results showed that an increase in sweetness and firmness and a decrease in sourness were associated with an increase in overall acceptance. Sourness and sweetness were positively correlated with CIE $L^*$ (r=0.88) and firmness (r=0.95), individually. In the principal component analysis results, component F1 and F2 explained 44.35% and 33.77%, respectively, of the total variance (78.12%). F1 represented firmness, sweetness, elasticity, hardness, grape odor, color intensity, sweet odor, sourness, and damage degree. F2 represented CIE $L^*$, TA, CIE $a^*$, CIE $a^*/b^*$, SSC/TA, SSC, and peel thickness. The results showed that consumer acceptance of 'Campbell early' grapes can be determined by assessing physicochemical attributes of firmness, CIE $L^*$, TA, CIE $a^*$, CIE $a^*/b^*$, SSC/TA, and SSC and various sensorial attributes including sweetness, fruit elasticity, fruit hardness, grape odor, and color intensity.

• 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.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.637-642
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• 1993

Changes in the physicochemical characteristics and triglyceride molecular species of corn oil under the following condition of hydrogenation; temperature $180^{\circ}C,\;H_{2}$, pressure $2.0{\pm}0.3bar$, the amount of Ni catalyst 0.048%(Ni/oil by wt.) and agitation speed 300 rpm. The rate of hydrogenation, expressed as the reduction rate of the iodine value with respect to time, is first order and high (K>0.01). When the reduction rate of the iodine value was 39.9%, hydrogenation time was 30 min, 18:1 was highest(77.06%), thereafter that was decreased and 18:0 increased. In the triglyceride composition, OLL, LLL were reduced markedly in 10 min, thereafter reduced slightly. And PLO, PLL, OLO were eliminated in first 30 min. On the other hand, POO, PLS(CN52) and OOO, SLO(CN54) were increased sharply, and then that showed little change. The melting point(MP) of hydrogenated corn oil were $27.8^{\circ}C\;and\;44.1^{\circ}C$ after 20 min and 60 min, respectively. Trans isomer content increased to 46.8% during 40 mins of hydrogenation and then decreased insignificantly. The solid fat content were linearly increased with hydrogenation time. Accordingly, it is confirmed that this condition of hydrogenation was selective, preferential elimination of polyunsaturated fatty acid went stepwise and trans isomer was formed promotedly. These results suggest that fat modification techniques can be used for practical application.

• Korean Journal of Medicinal Crop Science
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• v.13 no.1
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• pp.52-56
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• 2005

This study was compared the quality of red ginseng and characteristic changes of physicochemical properties according to the storage period (non storage, two days, six days, eight days, ten days) and store temperature $20^{\circ}C, \;34^{\circ}C,\;-10^{\circ}C)$. The water content of the fresh ginseng has a tendency to decrease as storage time increases. When we store the fresh ginseng for 10 days, the ideal storage temperature is considered to be $34^{\circ}C$ degrees. The amount of total nitrogen has a tendency to increase more than that of no storage as storage period approaches to 10 days. In the storage temperature, the amount of total nitrogen has a tendency to increase in the order of 1) room temperature, 2) freezing storage, 3) cold storage more than no storage. Cold storage has larger contents of total phenolic compounds than room temperature and freezing storage according to storage temperature. When we analyze the changes of a relative density of eight elements, ginsenoside $Rb_1,Rb_2,Rc,Rd,Re,Rg_3,Rg_1\;and\;Rg_2$ in red ginseng's saponin Rf according to storage condition, the relative density of $Rb_1\;and\;Rg_1$ against Rf diminishes in each storage condition as storage time increases. And it is also thought that density change of ginsenoside appears because of the materials, and change tendency according to storage condition is not clear. From functional nature on the evaluation of the quality, taste and fragrance of red ginseng according to storage district, it is evaluated that it is most recommendable for red ginseng to be transported and stored in $3{\sim}4$ degrees to keep its best condition.

• Korean Journal of Food Science and Technology
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• v.39 no.4
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• pp.476-479
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• 2007

In order to promote the utilization of Rubus coreanus Miquel as a functional food, its physicochemical properties were examined during maturation. Crude protein, crude ash, and dietary fiber contents were highest in the unripened fruit, but decreased thereafter; whereas as moisture and the soluble solid contents showed a reverse pattern. The free sugar concentration of the middle-ripened fruit (0.7 g/100 g) increased as it became a ripened fruit (4.1 g/100 g). Also, the acidity of R. coreanus Miquel was at its highest concentration in the middle-ripened fruit at 3.38%. Seventeen types of amino acids were analyzed from R. coreanus Miquel during maturation. The highest amino acid components in the unripened fruit were aspartic acid (546.55 mg/100 g) and glutamic acid (452.22 mg/100 g). Among the minerals studied during this research, R. coreanus Miquel contained a high level of potassium. The potassium concentrations of the unripened fruit, middle-ripened fruit, and ripened fruit were 306.0, 191.1, and 164.1 mg/100 g, respectively.

• Korean Journal of Food Science and Technology
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• v.46 no.6
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• pp.723-728
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• 2014

The physicochemical characteristics of coffees extracted using 7 different extraction methods were investigated. The pH values of coffees extracted via different extraction methods ranged from 5.26 to 5.54, and coffee extracted by Ibrik had the highest pH among all samples. The soluble solid content and titratable acidity of coffee extracted using an Espresso machine were significantly higher than those obtained using other extraction methods. Furthermore, the total phenol and caffeine contents of coffee extracted using an Espresso machine were 6.46 and 2.65 mg/mL, respectively. In regard to color, the $L^*$, $a^*$ and $b^*$ values of coffee extracted via different extraction methods were in the ranges of 0.81-38.94, 4.49-37.75, and 0.71-66.42, respectively. In regard to the phenolic compounds, the chlorogenic acid, caffeic acid and ferulic acid contents of coffee extracted using an Espresso machine were higher than those obtained by other extraction methods at 0.15 mg/mL, $0.075{\mu}g/{\mu}L$, and $0.019{\mu}g/{\mu}L$, respectively.

• Korean Journal of Food Science and Technology
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• v.22 no.6
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• pp.681-685
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• 1990

Changes in the physicochemical characteristics and trans acid of cottonseed oil under the condition of selective hydrogenation, temperature$210^{\circ}C,\;H_2\;pressure\;0.3\;kg/cm^2$ Ni catalyst amount 0.12% (in oil), agitation speed 280 rpm, were investigated. The saturated fatty acid such as palmitic acid and stearic acid did not show any difference, while linoleic acid($50.03%{\rightarrow}9.38%$) were transformed to oleic acid ($20.65%{\rightarrow}60.35%$) during hydrogenation. In linoleic acid isomers, cc form were reduced significantly, but ct, tc, tt form showed little change, respectively. In oleic acid isomer, t form increased markedly, whereas there was no significant difference in c form. Meanwhile, melting point(MP) and solid fat content (SFC) were linearly increased, but iodine value(IV) linearly decreased as hydrogenation proceeded. From these results, linear regression equations were obtained as follows. MP & IV : Y= 1.59-2.36X(r=-0.96, p<0.05), SFC($at\;20^{\circ}C$) & MP : Y=2.81+2.01X(r=0.96, p<0.05), SFC($at\;20^{\circ}C$) & IV : Y=9.40-5.16X(r=-0.99, p<0.01), SFC($at\;20^{\circ}C$) & 18 : 1t : Y=6.25+8.48X(r=0.97, p<0.05)

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1104-1111
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• 2014

To investigate major characteristics affecting the consumer acceptability of Cheonggukjang, the physicochemical characteristics and consumer perception of 16 Cheonggukjang samples (seven commercial samples and nine samples prepared in the laboratory) were analyzed. Overall, consumer acceptability of Cheonggukjang increased with higher contents of amino nitrogen and volatile basic nitrogen, as well as at lower moisture contents. Cheonggukjang samples with higher consumer acceptability showed higher purchase intent (%) and willingness to pay (won/200 gram package), implying consistency in consumer evaluation. Ideal characteristics of Cheonggukjang were lighter color, less water in the soup, stronger characteristic Cheonggukjang taste, sweetness and nutty taste, as well as less off odors, saltiness, and bitterness. The result of this study demonstrates the needs to improve sensory quality by considering the relatively low consumer acceptability of Cheonggukjang samples.

• Food Science of Animal Resources
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• v.21 no.1
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• pp.80-88
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• 2001

This study was carried out to evaluate the different physicochemical properties of various lipid sources in beef patties during storage for 6 months. Four groups of samples were made of beef meat patties with 22% of tallow, lard, chicken fat and 20% of palm oil. On the analysis result of physicochemical compositions, the patty has its own fatty acids composition and characteristic different from other lipids. Patty with chicken fat has the highest percentage of unsaturated fatty acid composition of 61.0% compared to the other groups of patties. Beef patty with chicken fat has 18.8% of poly unsaturated fatty acid(USFA) and beef patty with beef lipid has 1.5% of poly USFA which is the least percentage among the others. SFA/USFA ratio of beef patty with chicken lipid was 0.5 which was the least value. The composition of PUFA in beef patty with lard increased to 10.0% from 1.9% over initial value after storage for 6 months. On the contrary, the composition of PUFA in beef patty with chicken fat decreased to 9.2% from 18.8% over initial value after 6 months. Volatile free fatty acids of beef patties were evaluated with four kinds of lipid sources. Formic acid was the most as of 59$\mu\textrm{g}$/g in beef patty with tallow, acetic acid was 15$\mu\textrm{g}$/g, and heptanoic acid was 10$\mu\textrm{g}$/g at starting time of storage. However, propionic acid, butyric acid, valeric acid and caproic acid were not detected. After 6 months, formic acid decreased from 59$\mu\textrm{g}$/g to 7$\mu\textrm{g}$/g in the patty with tallow, from 12$\mu\textrm{g}$/g to non-detect level in the patty with palm oil, but two the others patties slightly increased. Volatile compounds in meat patties were reported nearly 1000 kinds of chemical compounds. Beef patty with tallow has aldehydes 5.3, alcohol 1.3, hydrocarbon 0.8, ketones 0.2, ester 0.1, furans 0.1, acid 0.04, sulfur 0.03 in peak area at starting and increased to aldehydes 8.5, alcohol 2.1, ketones 0.5, ester 1.0, furans 1.5 in peak area during the storage. But only furans was not detected after 6 months of storage. From starting to 6 months, aldehydes increased 2∼10 times, alcohol increased 2∼3 times, acids 4∼50 times and ester 9∼20 times in beef patties with pork lipid, chicken lipid and palm oil. Some volatile compounds such as alcohol, aldehydes and acids in all kinds of patties significantly increased after 6 months of storage. These increases cause oxidative rancidity taste in meat patties. These results showed that selt-life of meat patties with 4 different lipids were not over 6 months even though they were stored at -20$^{circ}C$. Therefore, they should be classified as off-grade because of oxidative rancidity. Although beef patties with tallow are currently common type, the possibility for new type of hamburg patty can be developed by applying different lipids. Finally, we found out new type of beef patty added with lard, which has the best taste and quality compared to the other common types.

• Journal of the Korean Society of Food Culture
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• v.34 no.2
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• pp.217-223
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• 2019

This study aimed to evaluate the characteristic differential between whole cabbage kimchi (pogi kimchi) and sliced cabbage kimchi (mat kimchi) during kimchi fermentation at $6^{\circ}C$. The difference of microbial and physicochemical properties was investigated until 6 weeks. For the changes in the microbial flora, both kimchi samples exhibited a continuous increase in total aerobic bacteria and lactic acid bacteria (LAB) population size up to 2 weeks followed by a stationary phase until 5 weeks. Interestingly, the number of LAB of mat kimchi was overall higher than that of pogi kimchi during kimchi fermentation. We speculate that mat kimchi has in a more advantageous growth condition than pogi kimchi for microbial growth because small kimchi cabbage size appropriately derives nutritional supply in order to increase the LAB growth. During lactic fermentation at $6^{\circ}C$, physicochemical changes in the pH, salinity, and titratable acidity was observed to be no significant differences between two types of kimchi. Furthermore the contents of organic acids such as oxalic acid, citric acid, malic acid, lactic acid, fumaric acid, and acetic acid was not significantly different (p>0.05) between both kimchi samples as well as the contents of total free amino acid.