• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.6
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• pp.957-963
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• 2013

This study evaluated the quality characteristics of muffins prepared with different amounts (0%, 4%, 8%, or 12%) of apricot powder. The moisture content was higher in groups containing 8% and 12% apricot powder. The specific volume of muffins decreased as the amount of apricot powder increased. The lightness value was lower in groups containing apricot powder, with redness and yellowness values increasing with increasing amounts of apricot powder. Rheology tests showed no significant differences in hardness, springiness, and cohesiveness between control muffins and muffins with apricot added. Scanning electron microscopy showed that the number and size of air cells decreased with increasing levels of apricot powder. The substitution of wheat flour with apricot powder yielded muffins with a higher DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging activity and total polyphenol content. Consumer acceptance tests revealed no significant differences in appearance, smell, and texture between muffin samples, but the taste and overall acceptability scores were lowest for muffins with 12% apricot added. Therefore, up to 8% apricot powder can be incorporated into muffins to meet the sensory quality and functional needs of the consumer.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.520-526
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• 2013

To determine the kimchi with the best quality and functional characteristics, we manufactured and compared recipes for Korean and Japanese kimchi made either Korean or Japanese baechu cabbages. All batches were fermented for 4 weeks at $5^{\circ}C$, and tested for pH, texture, microbial count, sensory evaluation, DPPH radical-scavenging activity, and cell proliferation (using the MTT assay on AGS human gastric cancer cells). By the third week of fermentation, Korean kimchi made with Korean baechu (KK) and Japanese kimchi made with Korean baechu (KJ) showed a higher acidity than Korean or Japanese kimchi made with Japanese baechu (JK and JJ, respectively). KK ranked highest in springiness, followed by KJ, JK, and JJ. Therefore, the texture of kimchi produced with Korean baechu was appears better than kimchi produced with Japanese baechu. This was confirmed in masticatory tests. Kimchi produced with Korean baechu (KK and KJ) showed lower total aerobic bacterial counts, while the total lactic acid bacterial counts were higher (p<0.05). In sensory evaluation test, KK received the highest overall acceptability score, while JJ earned the lowest score. In the DPPH assay for anti-oxidative activity, KK showed a 94% anti-oxidative effect, followed by KJ (92%), JK (91%), and JJ (88%) (p<0.05). In the MTT assay for analyzing the cell proliferation of AGS human gastric cancer cells, KK showed a 64% anticancer effect in vitro, followed by KJ (57%), JK (38%), and JJ (26%). Therefore, the anti-oxidative and anti-cancer functionalities of kimchi made with Korean baechu were higher than those made with Japanese baechu, regardless of the kimchi recipe applied. Overall, Korean baechu had important and superior effects on the quality and functionality of kimchi.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1626-1631
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• 2012

Sixty strains of lactic acid bacteria were isolated from kimchi and used as a starter for fermented tofu. Among the isolated strains, strain KL-6 showed antimicrobial activity against various pathogens, antioxidative activity, and viability in artificial gastric juice and artificial bile acid. The selected strain KL-6 was identified as Pediococcus acidilactici KL-6 by morphological and physiological tests, including Gram staining, catalase test, and 16S rRNA sequencing. The fermentation characteristics of tofu with a kimchi ingredient mixture (Control) consisting of red pepper, garlic, ginger, sugar, salt, jeotgal, and juice of chinese cabbage were compared with those of tofus inoculated with strain KL-6 and the kimchi ingredient mixture (TL) or a pre-fermented kimchi ingredient mixture (TPL) for 24 hr at $37^{\circ}C$. The pH levels of all tested tofu samples decreased after 1 week of fermentation, reaching 3.96 (control), 3.97 (TL), and 4.03 log cfu/g (TPL) after fermentation for 14 weeks at $20^{\circ}C$. Total aerobe content of fermented tofu increased until 2 weeks of fermentation, but decreased steadily thereafter. The number of lactic acid bacteria reached $10^6$ cfu/g after 1 week of fermentation in TL and TPL, whereas it took 2 weeks for the control. The number of lactic acid bacteria in all tested tofu samples reached $10^3$ cfu/g after 14 weeks of fermentation at $20^{\circ}C$. Coliform bacteria were not detected in TL or TPL after 1 week of fermentation. The sensory scores of TL and TPL were higher than that of control in terms of taste, flavor, texture, and overall acceptability. The sensory quality of TPL was the best among all tested fermented tofu samples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.759-765
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• 2013

In this study, we investigated the quality characteristics of Sikhye, a traditional Korean drink, made with various amounts (0.5, 1, 2, and 3%) of powder from the roots of Doraji (RPD), for different storage periods (1, 3, 5, 7, 10, 13, or 15 days). The pH and Hunter's L value of Sikhye decreased with higher amounts of added RPD, while saccharinity as well as "a" and b values increased. During storage, pH and Hunter's L value of Sikhye tended to decrease while "a" and b values increased. The saccharinity of Sikhye with 0.5% and 1% RPD reached its maximum values on the tenth storage day and continuously decreased during the storage period. In contrast, the saccharinity of Sikhye with 2% and 3% RPD increased during the storage period, and had its maximum saccharinity on the fifteenth storage day. During the storage of Sikhye the total microbial cell count, typically $3.19{\sim}0.35{\times}10^2$ CFU/mL on the third storage day, was undetected in Sikhye with 3% RPD. The total microbial cell count of Sikhye without RPD increased to $1.91{\times}10^9$ CFU/mL by the fifteenth storage day, while Sikhye with 0.5, 1, 2, and 3% RPD added contained $8.43{\times}10^8$, $9.77{\times}10^7$, $2.10{\times}10^7$, and $7.21{\times}10^6$ CFU/mL, respectively. Thus, the total cell count was lower with higher additions of RPD. In sensory tests, the Sikhye control, or with 0.5% and 1% RPD added, didn't show significant differences in the texture of rice granules, plumpness of rice granules, floating of rice granules, taste, flavor, and sweetness values. The overall preference was highest (5.38) for Sikhye with 0.5% RPD, followed by the control, 1% RPD, 2% RPD and 3% RPD. In conclusion, according to preference tests, we recommended the addition of 0.5% or 1% RPD in Sikhye.