• Korean Journal of Food Science and Technology
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• v.50 no.3
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• pp.331-338
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• 2018

The purpose of this study was to determine the optimum sterilization conditions for the production of retorted steamed egg using response surface methodology. Sterilization processes for eighteen conditions using varying sterilization temperature ($X_1$), time ($X_2$), and method ($X_3$) as the independent variables were carried out through a $3^2{\times}2$ experimental factorial design. Quality evaluations after sterilization included measurements of $F_0$ value ($Y_1$), peak stress ($Y_2$), pH ($Y_3$), color value ($Y_{4-6}$), and organoleptic test [preference for appearance ($Y_7$), overall acceptability ($Y_8$), and preference for texture ($Y_9$) and egg taste ($Y_{10}$)]. Dependent variables ($Y_{1-10}$) of eighteen conditions were more affected by temperature and time than by the sterilization method. Eight factors were selected among the dependent variables as significant factors related to the quality of the steamed egg. Finally, by establishing an optimum range of each dependent variable and contour analysis, the optimum sterilization conditions for the production of steamed egg were determined to be $120^{\circ}C$ for 25 min using a 2-step sterilization process.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.349-356
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• 2005

For the purpose of making a new type of functional drinkable yoghurt, skim milk containing $0.5\~2.0\%$(w/v) green tea powder was fermented by the mixed stains of Streptococcus thermophilus and Lactobacillus acidophilus. Quality characteristics of the drinkable yoghurts were evaluated in terms of quality-keeping properties(number of viable cells, pH, titratable acidity) and sensory properties. When the drinkable yoghurts added with $0.5\~2.0\%$ green tea powder were kept at $4^{\circ}C\;and\;20^{\circ}C$ for 20 days, the number of viable cell counts of the lactic acid bacteria($2.1\times10^8\~6.2\times10^8$ CFU/mL). pH($4.16\~4.22$) and titratable acidity($0.792\~0.881\%$) were not significantly changed for all drinkable yoghurts during the storage at $4^{\circ}C\;and\;20^{\circ}C$ days, but the number of viable cell counts($4.2\times10^3\~1.8\times10^5$ CFU/mL), pH($3.82\~3.92$) and titratable acidity($1.057\~1.174\%$) were markedly changed f3r the storage at $20^{\circ}C$ for 20 days. Therefore the keeping quality of the drinkable yoghurts with addition of green tea powder was relatively good at $4^{\circ}C$ for 20 days. The results of sensory evaluation of the drinkable yoghurts containing peen tea powder indicated that flavor, sweet taste, mouthfeel and aftertaste of the drinkable yoghurt with $0.5\%$ green tea powder showed higher preference than others. And the drinkable yoghurt containing $0.5\% green tea powder added $20\%$(v/v) oligosaccharide had the higher sensory scores in sweet taste, aftertaste and overall acceptability among the treatments.

• The Korean Journal of Food And Nutrition
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• v.27 no.1
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• pp.22-30
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• 2014

In this study, purple sweet potato bread was prepared by the addition of 0.005%, 0.010%, 0.015% and 0.020% hemicellulase. It's effect on product quality and consumer evaluation were examined. The results showed that the dough pH and total titratable acidity were not significantly different between samples. In the fermentation power of dough expansion, a 0.015% addition sample was the highest between the samples. The bread pH decreased significantly as hemicellulase was increased, whereas. Bread total titratable acidity was significantly decreased. The addition of hemicellulase samples were significantly higher in specific volume and baking loss than the control sample. The moisture content was not significantly different between samples. In colors, the lightness of the control sample was the highest, the redness of the 0.020% addition sample was the lowest while the yellowness of the control was the lowest. The hardness and the fracturability decreased significantly as hemicellulase was increased. The resilience indicated reverse effects. In consumer evaluation, the color and softness were not significantly different between samples. And the hemicellulase addition of samples was higher in flavor than that of the control sample. The overall acceptability was the highest at 5.67 with a 0.010% addition sample. According to these results, the addition of 0.010% hemicellulase in purple sweet potato bread would be the optimum level.

• Korean journal of food and cookery science
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• v.28 no.4
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• pp.391-397
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• 2012

This study was carried out to investigate commercialization of Kimchi made of cabbage (Brassica oleracea var. capitata L.) using pre-fermentation conditions. The pre-fermentation conditions were 0, 18, 24, and 28 h at $20^{\circ}C$, and then the samples were stored at $10^{\circ}C$ to assess changes in quality characteristics. A comparison of the quality characteristics during storage showed that PF24 (pre-fermented cabbage Kimchi during 24 h at $20^{\circ}C$) and PF28 (pre-fermented cabbage Kimchi during 28 h at $20^{\circ}C$) had pH 4.47 and pH 4.23 on the second day of storage, respectively. It was possible to shorten the fermentation time to less than that of PF0 (not pre-fermented cabbage Kimchi at $20^{\circ}C$), by approximately 3 days. Total acidity was 0.26 to 0.29% immediately after making the Kimchi. However, PF0, PF18 (pre-fermented cabbage Kimchi during 18 h at $20^{\circ}C$), PF24 and PF28 became well-fermented when they were stored for 8~14 days, 3~10 days or 2~3 days. The number of lactic acid bacteria increased with the passage of time in all treatment groups regardless of fermentation conditions. However, the longer pre-fermentation time became, the faster the number of lactic acid bacteria increased. Most samples showed similar results late in the storage period; 7.2~7.4 log CFU/mL. PF0 had the greatest volume change 2.1 times increase late in the storage period. The sensory evaluation showed significant differences for flavor, taste, and overall acceptability after a partial storage period. PF28 stored for 2~3 days showed excellent flavor, and PF24 and PF28 stored for 2~3 days showed the highest scores of 6.27 to 6.67. The PF24 and PF28 treated samples were appropriate for commercializing small packed cabbage Kimchi and for alleviating the expansion problem of the packing material. However, because mass commercial production requires a large number of samples to be used at once, the results should be assessed for industrial product development in the future.

• Food Science of Animal Resources
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• v.28 no.4
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• pp.486-492
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• 2008

We investigated the quality properties of pork jerky prepared with various humectants (Konjac, egg albumin, isolated soy protein). Jerky was prepared as follows; control with no humectants, treatments with 0.05, 0.1, and 0.2% humectants, respectively. Humectant treatments had higher drying yields of pork jerky than the control (p<0.05), Konjac treatment produced the the highest drying yields among the humectants tested. CIE a-and b-value were lowest in isolated soy protein treatments. b-value in 0.2% egg albumin treatments were higher than other treatments (p<0.05). Jerky water content increased as humectant content increased. Water activity (Aw) in 0.2% Konjac treatments was higher than controls and 0.05% Konjac (p<0.05). In textual profile evaluations, control samples had greater hardness, cohesiveness, gumminess, and chewiness values than other treatments, but very low springiness (p<0.05). Control had significantly (p<0.05) lower scores than the other treatments in sensorial texture, juiciness and overall acceptability. Based on our findings, we conclude that 0.05% Konjac was the most effective humectant among those we tested in this study.

• Food Science of Animal Resources
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• v.29 no.3
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• pp.382-390
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• 2009

This study was carried out to determine the effects of tomato powder (TP) as nitrite (NT) on pork patties. The following treatments were made: 0.01% NT (Tl), 0.01% NT and 1.0% TP (T2), 0.5% TP (T3), 1.0% TP (T4), and 0.01% NT and 1.0% TP (T5) were in basal formula (C). The following observations were made: T5 displayed lower gumminess and adhesiveness values than those of C and T1 (p<0.05) on Day 1 of storage; the hardness and surface hardness of T3 and T4 were relatively lower and the surface hardness and gumminess of T3 were relatively higher than the others (p<0.05) on Day 21 of storage; Y4 had significantly lower TBARS values than the others during storage; VBN values of the tested groups were significantly lower than the control samples on Day 7 and 21 of storage; T3 and T4 samples displayed lower pH values (p<0.05) than the control samples on Day 21 of storage; T3, T4 and T5 revealed lower CIE $L^*$ and W than those of C and T1 during storage; T2 had the highest CIE $a^*$ (p<0.05); T4 had significantly higher CIE $b^*$ and chroma values than those of others; T3 and T4 had significantly lower total plate counts than the others; T1 had significantly lower yeast and mold and Staphylococcus sp. counts than the other groups'; and T1 and T2 displayed significantly higher color acceptability than the others.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.125-132
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• 2013

In the present study, to determine the effects of terminal sire strains, carcass characteristics, yields of retail cut, and meat quality of 425 pigs were examined. Terminal sires were divided into five strains (D1, D2, B1, B2, and BD) based on the countries of origin and breeds. The strains D1 and D2 showed high grade 1+ appearance ratios and strains B1, B2, and D1 showed high appearance ratios of carcass yield grade A. As for the real retail cut yields of meat, strain D1 showed large real retail cut yields of meat in shoulder, rib, fore leg, loin, belly, tenderloin and hind leg. Moisture contents were significantly higher in strain B1, and protein and fat contents were significantly higher for strain D1 than in the other strains (p<0.05). Shear force values were significantly higher for strain B1 than in the other strains (p<0.05). For meat color properties, the lightness were significantly higher in strains D1, D2, and BD, and the yellowness were significantly higher in strains D1, D2, and BD relative to the other strains (p<0.05). In sensory evaluation, drip of strains D1 and D2 were significantly lower while marbling and overall acceptability were significantly higher in the other four strains (p<0.05). Therefore, when considering the results of the present study comprehensively, using strains D1 and D2 that showed high grade 1+ appearance ratios, large real retail cut yields of belly, significantly higher lightness and sensory evaluation will be helpful to the incomes of producers and farm households.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.1
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• pp.58-64
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• 2007

Antioxidative activity and functional properties of the powder obtained from ground Opuntia ficus-indica var. saboten fruit were studied. Cupcakes containing 1,3, and 5% (w/w) of O. ficus-indica vu. saboten powders were prepared and evaluated for their sensory property, textural quality, and shelf-life. The antioxidative activity, measured by DPPH radical scavenging activity of O. ficus-indica var. saboten powder, increased as the concentrations of O. ficus-indica var. saboten powder increased. No coliform bacteria, yeasts, and molds were detected in either the O. ficus-indica var. saboten powder or in the cupcakes. However, total aerobic bacteria counts were 4.41 log CFU/g in the O. ficus-indica var. saboten powder and were a negligible level (<$10^2$ CFU/g) in the cupcakes. Moisture content of the cupcakes was not significantly different in all samples. Lightness (L) and yellowness (b) of cupcake color decreased as the concentration of O. ficus-indicar var. saboten powder increased, whereas the redness (a) increased. Increasing the concentration of O. ficus-indica var. saboten powder, the mechanical characteristics of the cupcakes, such as hardness, gumminess, and chewiness, while decreasing cohesiveness and springiness. The sensory properties, such as color, flavor, taste, texture, and overall acceptability, of the cupcakes containing the 1% 0. ficus-indica var. saboten powder were superior to the control sample. The results exhibited that the adding the O. ficus-indica var. saboten powder into the cupcakes increased antioxidant activity and showed no effect on shelf-life of the cupcakes. The highest quality improvement was obtained by incorporating the 1% (w/w) of 0. ficus-indica var. saboten powder into the cupcake formula.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.896-903
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• 2015

The objective of this study was to investigate the effect of nitrite substitution of sausage with purple sweet potato by examining the quality characteristics of sausage. Four sausage samples were prepared as follows: F1 (0.15% sodium nitrite), F2 (0.2% pigment), F3 (0.2% pigment and 5% powder), and F4 (0.2% pigment and 10% powder). A substitution of sodium nitrite with 0.2% purple sweet potato pigment reduced redness while increased yellowness. However, the addition of 5% purple sweet potato powder to 0.2% purple sweet potato pigment increased redness while reduced yellowness, which was similar to those of sausage with 0.15% addition of sodium nitrite. Further, color change increased as the content of purple sweet potato increased. As the amount of purple sweet potato increased, the contents of Ca, K, and Mg increased but hardness, gumminess, and chewiness decreased. In the sensory evaluation, the addition of purple sweet potato did not influence on appearance, color, or flavor. However, the addition of 10% purple sweet potato decreased the taste and texture of sausage. Correlation coefficients between overall acceptability, texture, appearance, color, taste, and flavor were 0.901, 0.895, 0.877, 0.844, and 0.688, respectively. Therefore, proper content of purple sweet potato powder and purple sweet potato pigment were determined to be 5% and 0.2%, respectively, for the substitution of sodium nitrite.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.840-846
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• 2015

We investigated blueberry wine made using traditional yeast (Saccharomyces cerevisiae M-5) and Saccharomyces cerevisiae Fermivin which is widely used in wine manufacturing, and measured its fermentative characteristics and antioxidant activity. S. cerevisiae M-5 is a traditional yeast isolated from domestically grown Black raspberry (Rubus occidentalis). Both S. cerevisiae M-5 and Fermivin were inoculated into blueberry juice (BBJ) up to $1{\times}10^9CFU/kg$, followed by incubation at $25^{\circ}C$ for 39 days. Final fermentation products of blueberry fermented with S. cerevisiae M-5 (BBM) presented 13.10% alcohol, $8.42^{\circ}Bx$ of sugar, and 1.183% acidity, and final fermentation products of blueberry fermented with Fermivin (BBF) presented 14.20% alcohol, $8.2^{\circ}Bx$ of sugar, and 1.153% acidity. The contents of total polyphenol and flavonoid compounds of BBM were higher than those of BBF and BBJ. DPPH and ABTS radical scavenging activities and reducing power of BBM were higher than those of BBF. The sensory evaluation revealed that BBM showed excellent flavor, taste, and overall acceptability compared with BBF. Based on these results, the possibility of industrial utilization of S. cerevisiae M-5 as traditional yeast was confirmed by sensory evaluation and antioxidant activity. Fermentation rate of S. cerevisiae M-5 was similar to Fermivin, which is used in the food industry.