• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.63-69
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• 2008

For the development of mulberry wine, we investigated its optimum fermentation conditions as well as quality changes during fermentation. The physicochemical characteristics of the mulberry fruit used in the study were pH 4.56, 0.50% titratable acidity, and 13.0 $^{circ}Brix$ soluble solids. The mulberry wine fermented with Saccharomyces cerevisiae KCCM 12224 (Sc-24) at 24 $^{circ}Brix$ soluble solids and $26^{circ}C$ showed excellent characteristics in terms of ethanol production, titratable acidity, and redness. The sucrose, fructose, and glucose contents of the mulberry wine drastically decreased with fermentation time. The citric acid content was maintained during the fermentation period, and malic acid decreased, but lactic and succinic acids increased. The cyanidin-3-glucoside content, a major anthocyanin pigment, of the mulberry wine drastically decreased from 195.5 mg% at the initial stage of fermentation to 15.37 mg% at 2 days of fermentation. However, cyanidin-3-rutinoside decreased gradually. In summary, a mulberry wine of high quality was made by fermentation for 8 days at $26^{\circ}C$ using mashed mulberry fruit containing $24^{\circ}Brix$ soluble solids, after adding 200 ppm $K_2S_2O_5$ and inoculating with 3%(v/v) Sc-24.

• The Korean Journal of Food And Nutrition
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• v.31 no.1
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• pp.127-134
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• 2018

To prolong the shelf-life of chicken breast meat, samples were treated with gel packs containing slow-released chlorine dioxide ($ClO_2$) gas at 7~15 ppm for eight days at $4^{\circ}C$. The microbial, physicochemical properties and sensory evaluation of the treated samples were investigated. The total number of bacteria in the control increased during storage and showed 6.78 log CFU/g on the 8th day of storage, but $ClO_2$ gas treatments showed 6.24~6.58 log CFU/g at the same time. The initial pH of chicken breast meat was 6.00 and gradually increased during storage. And $ClO_2$ gas treatments did not show any significant difference from the control during storage period, but maintained a generally lower pH than that of the control. The lightness, redness, and yellowness during storage were not significantly different between the control and the 7~10 ppm $ClO_2$ gas treatments. However, as the storage period was increased, the redness of 15 ppm $ClO_2$ gas treatment was reduced. The cooking loss and shear force were not different between the control and $ClO_2$ gas treatments during the storage period. Volatile basic nitrogen (VBN) increased in the control from the 6th day of storage and 23.80 mg% in the 8th day of storage. However, VBN of $ClO_2$ treatments showed lower than that of the control. In the change of sensory evaluation during storage, 10 ppm $ClO_2$ treatment showed the highest preference in odor, appearance and overall acceptance during storage period.

• Food Science of Animal Resources
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• v.36 no.1
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• pp.68-76
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• 2016

This study was conducted to investigate the meat quality and sensory properties of 12 major cuts from 10 Hanwoo bulls (25-32 mon of age) after they were aged at 2℃ for 0, 7, 14, and 21 d. Protein content (%) was between 19.17 and 22.50%. Intramuscular fat content ranged from 2.79 to 8.39%. The collagen content of the chuck roll, chuck tender, and short plate muscles was higher (1.97-2.04%) than that of the striploin muscles (1.48%) (p<0.05). CIE lightness (L*) values increased with an increase in aging days for tenderloin, loin, chuck roll, oyster blade, short plate, top sirloin, and eye of round muscles (p<0.05). Most muscles, except the short plate, showed no significant changes in redness CIE (a*) and yellowness (b*) color values during aging. The tenderloin, loin, and striploin showed significantly higher water holding capacity (58.60-62.06%) than that of chuck roll and short plate (53.86-57.07%) muscles (p<0.05). The Warner-Bratzler shear force values of most muscles decreased significantly as the aging period increased (p<0.05), exception the tenderloin. The chuck tender muscles showed the highest cooking loss, whereas tenderloin muscle showed the lowest (p<0.05). The tenderloin muscle had the longest sarcomere length (SL) (3.67-3.86 μm) and the bottom round muscle had the shortest SL (2.21-2.35 μm) (p<0.05). In the sensory evaluation, tenderness and overall-likeness scores of most muscles increased with increase in aging days. The tenderloin and oyster blade showed relatively higher tenderness and overall-likeness values than did the other muscles during the aging period. No significant differences were noted in juiciness and flavor-likeness scores among muscles and aging days.

• Korean Journal of Food Science and Technology
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• v.33 no.3
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• pp.288-293
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• 2001

${\alpha}-amylase$ activities of bean water was not significantly influenced by bean water concentrations but they were remarkably influenced by different temperatures and substrates. ${\alpha}-amylase$ activities of bean water on cooked starch were significantly higher than those on raw starch. ${\beta}-amylase$ and glucoamylase activities in 14% bean water were significantly higher than those in 7% bean water. Yukwa paste is glutinous rice flour paste. Bean water was added to Yukwa paste by 0, 7, 14% and incubated 0, 3, 6, 9, 12 hours at $60^{\circ}C$. The pH of Yukwa paste increased with bean water concentration and decreased with the incubation time. The viscosity decreased with bean water concentration and incubation time. The ruducing sugar content of Yukwa paste increased with bean water concentration and incubation time. The changes of reducing sugar content in cooked Yukwa paste were much higher than those in the raw one. ${\alpha},\;{\beta}-amylase$glucoamylase activities of Yukwa paste also increased with bean water concentration, and their activities were much higher on the cooked glutinous rice flour than those on the raw one. The SEM observation on the freeze-dried flour of Yukwa paste showed breakdown of amylopectin structure by addition of bean water in the paste.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.569-575
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• 1988

Storage stabilities of ramyons fried in palm oil and beef tallow with added antioxidants and their synergists were investigated by comparing the changes in physicochemical parameters and n-hexanal concentrations of oils extracted from ramyons during storage. Ramyons fried in palm oil and beef tallow with added ${\delta}-tocopherol$ $({\delta}-toc)$ showed an enhanced storage stabilities when compared to those fried in the oils with ${\alpha}-tocopherol$ $({\alpha}-toc)$. Ascorbyl palmitate was found to be a better synergist than citric acid for the antioxidant activity of both ${\delta}-toc\;and\;{\alpha}-toc$. Phenolic antioxidants gave a better storage stability than tocopherol when ramyon was fried in beef tallow, while a mixture of BHA and BHT gave an inferior storage stability than${\alpha}-toc$ when ramyon was fried in palm oil. The effectiveness of the antioxidants tested on storage stability of stored ramyon had a close relationship to the n-hexanal concentration. On the other hand, the paramenters such as peroxide value, carbonly value, and conjugated diene concentration showed inconsistency during the course of the storage experiment.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.865-870
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• 1990

Four different fermentation methods of Korean cucumber pickles were compared with conventional method, pickling in 10% NaCl solution at $25^{\circ}C$, in order to improve the storage stability. The methods studied were brining the cucumbers in hot($90^{\circ}C$) 10% NaCl solution(method A), addition of KCl and $CaCl_2$ into the hot salt solution(method B) addition of a sodium salts mixture of phosphates, nitrite and citrate into half fermented pickles prepared by method B(method C), substituted nitrite and citrate with KCl in method C(method D). It was found from results that the method C and D reduced the decreasing rate of pH very significantly by more than 3 fold and method B also showed the reducing effect. However, higher total acidity was measured for method C and D, which was opposite to pH results. Changes in hardness of cucumber showed little difference to control while color of brining solution exhibited some difference in their Hunter values. Organoleptic comparison showed a clear effect of salts mixtures by receiving the significant higher scores in fresh cucumber flavor and lower values in yeast moldy and sour flavor for method C and D when those were compared to control.

• Journal of the Korean Chemical Society
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• v.38 no.6
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• pp.427-434
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• 1994

The retention behaviors of poly(ethylene-co-vinyl acetate)s have been studied by thermal field-flow fractionation(ThFFF) with respect to effective separation and characterization of thermal diffusion coefficients($D_{\tau}$) as one of the physicochemical properties of polymers. The eight copolymers are different in vinyl acetate composition ranging from 25% to 70% and in molecular weight ranging from 110,000 to 285,000. The carrier solvents are THF, toluene and chlorobenzene which have different viscosities and thermal conductivities. It is shown that the retention of a copolymer is dependent on the type of the carrier, the molecular weight and chemical composition of the copolymer. The results show that the retention of a copolymer increases when either vinyl acetate composition or the molecular weight increase. $D_{\tau}$ values measured by experiments vary from 1.36∼5.97 $\cm^2/(s.K)$ depending on the copolymer composition and the type of the carrier solvent. These values increase $(r^2{\geq}0.928)$ with increase of weight % of vinyl acetate. THF is found to be the proper carrier solvent for separation of copolymers employed in this study due to the fact that a $D_{\tau}$ value greatly changes with variation of copolymer composition. From the above results, ThFFF can be used for separation of copolymers with similar molecular sizes but different compositions.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.720-730
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• 2007

This study was investigated (replaced) the sensory and physicochemical properties of Jeungpyun substituted with 30% or 60% of brown rice and barley flours, respectively. The quality changes of the functional Jeougpyun during the storage periods were analyzed by a texturometer. We found that batter pH was decreased as fermentation progressed, but showed a higher pH resulted after steaming. The brown rice replaced Jeungpyun had higher specific gravity and lower viscosity; however, the barley-replaced Jeungpyun had lower specific gravity and higher viscosity compared to those of the control(0% replace with brown rice or barley flour). The barley-replaced samples showed significantly larger volume indexes than that of the control. The L-value of the for lightness decreased significantly within the replaced samples(p<0.001). All samples had negative a-values, with slight peen colors rather than red. The barley-replaced samples were darker than those of the brown rice sample groups, with less green and yellow color. The brown rice-replaced samples had larger values for adhesiveness, overall, and moistness, and the barley-replaced samples showed intensities greater in cell size, springiness, hardness, and flavor by sensory evaluation. The 30% flour-replaced samples of the comparisons had higher values for overall desirability(p<0.001). The replaced samples showed slow increases in hardness when measured by a texturometer, indicating that, the retrogradation rates decreased as the storage periods increased. The control stored for 72 hr had a hardness value that was 8.0 times harder than that of the control stored for one hour. The 30 and 60% brown rice-replaced samples stored for 72 hr were 5.8 times and 4.7 times harder of their replacement level, respectively, and the 30 and 60% barley-replaced samples stored for 72 hr were 5.7 times and 4.2 times harder of their replacement level, respectively. The adhesiveness and cohesiveness of all samples tended to decrease as the storage period increased. The barley-replaced samples showed significantly the lower adhesiveness and cohesiveness during the storage periods. The springiness of all samples decreased slowly during the storage periods. In conclusion, Jeungpyun that was substituted with brown rice and barley flours demonstrated improved functionality and higher dietary fiber replaced effect. Furthermore, the storage period of was extended as the retrogradation rate was delayed as a result of the dietary fibers.

• Food Science and Preservation
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• v.22 no.3
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• pp.377-384
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• 2015

This study examined the physicochemical quality characteristics of the oriental melon Makgeolli variant by addition of sucralose during its non-steamed fermentation process. The results showed a partial increase in initial sugar content in Makgeolli depending on the level of sucralose addition; and this slight increase in sugar content was exhibited in all intervals into which the sucralose was added during fermentation. The pH of Makgeolli did not exhibit significant changes according to the level of added sucralose until the fourth day of the fermentation process; and the total acidity of Makgeolli did not significantly change in accordance with the varied levels of added sucralose. Reducing sugar rapidly decreased in all intervals of the experiment during the first day of fermentation, and it was then increased slightly staring from the second day of the fermentation. Alcohol content in all experimental intervals was proportionally increased in accordance with the amount of added sucralose during the alcoholic fermentation process. The alcohol content was reached to the final alcohol contents of control (A) 11.27%, 0.001% (w/w) (B) 11.43%, 0.002% (w/w) (C) 11.80%, and 0.003% (w/w) (D) 12.23%. The levels of acetaldehyde, 1-propanol, isobutanol, and isoamyl alcohol in Makgeolli were all proportional to the level of the amount of sucralose added in the fermentation process. The organoleptic characteristics of Makgeolli was accorded with the level of the amount of sucralose. In the sensory evaluation, the experimental interval of 0.003% (w/w) (D) showed the highest scores of 3.30, 2.67, 3.17, and 3.20 in color, odor, taste and overall, respectively.

• Food Science and Preservation
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• v.18 no.5
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• pp.669-677
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• 2011

The objective of this study was to develop a functional drink using maca extract, and to evaluate the latter's antioxidative activity during storage. Maca extract was added in five different content percentages (0, 8, 16, 24, and 32%), and the physicochemical properties were investigated. The pH of the control drink was lower than that of the drink to which maca extract was added. The $^{\circ}Brix$ increased with the increasing amount of maca extract. The Hunter L value decreased while the yellowness (b) value increased as the maca extract level increased. The results of the consumer acceptance test showed that no significant differences in overall acceptability were observed between the control and the 8%-, 16%-, and 24% maca-added drinks. Therefore, it is suggested that up to 24% maca extract can be added to drinks without depressing the quality. The changes in the total polyphenol content, DPPH radical, superoxide anion radical activity, and tyrosinase inhibitory effect were monitored during storage at 4 and $37^{\circ}C$ for four weeks. The results showed that there was a gradual decrease in the total polyphenol content and antioxidant activities after four-week storage, and the drinks containing maca extract exhibited a smaller decrease in antioxidant activity than did the control drink. Moreover, microbial growth was not shown during the same periods.