• Food Science and Preservation
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• v.21 no.6
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• pp.824-830
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• 2014

In this study, the quality characteristics of cookies with added purple kohlrabi (Brassica oleracea var. gongylodes) powder were investigated and analyzed through chemical and sensory evaluation. Samples were prepared with different levels (0, 1, 3, and 5%) of freeze-dried kohlrabi powder. The addition of Kolarbi powder decreased the moisture and fat contents, but the ash content was significantly increased (p<0.05). The pH and density of the cookie dough decreased significantly with the increasing levels of kohlrabi powder added (p<0.05). The spread ratio of the cookies generally decreased as more kohlrabi powder was added, but the decrease was not statistically significant. The hardness of the cookies increased significantly, however, with the increasing levels of kohlrabi powder added (p<0.05). The Hunter's color L, a, and b values significantly decreased with increasing kohlrabi powder compared to those of the control (p<0.05). In the sensory evaluation, the cookies to which 3 and 5% kohlrabi powder were added showed remarkably higher values for color, taste and appearance. These results suggest that purple kohlrabi powder is a good ingredient for improving the sensory and quality characteristics of cookies.

• Korean Journal of Food Science and Technology
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• v.46 no.5
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• pp.601-608
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• 2014

In this study, we investigated the antioxidant activity of green kohlrabi juice (GKJ) and purple kohlrabi juice (PKJ) using various in vitro methods. The results of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities, ferric ion reducing antioxidant power (FRAP), reducing power, and nitrite scavenging activities showed that GKJ possessed higher antioxidant activity than PKJ. Green kohlrabi powder (GKJP) and purple kohlrabi powder (PKJP) inhibited hydrogen peroxide-induced cell death in human dermal fibroblasts. In addition, GKJP and PKJP suppressed intracellular reactive oxygen species (ROS) production induced by hydrogen peroxide in human dermal fibroblasts. These results suggest that green and purple kohlrabi juices are potential natural sources of antioxidants.