• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.478-485
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• 2017

The effect of high carbon dioxide and ethylene treatment on postharvest ripening regulation of red kiwifruit (Actinidia melanandra) was investigated during cold storage. Physio-chemical properties such as weight loss, firmness, SSC, acidity, and market quality were analysed in red kiwifruit held at $10^{\circ}C$ compared to the fruit treated with carbon dioxide and ethylene during 75 days of storage. No significant weight loss was detected in red kiwifruit treated with carbon dioxide until 75 days of storage while the most rapid loss was found in fruit treated with ethylene. In ethylene-treated fruit, the firmness was dramatically reduced from 4.2kg on the first day to 1.2 kg after 27 days of storage at $10^{\circ}C$. However, the firmness of the carbon dioxide-treated fruit was 1.8kg after 54 days of storage. The highest level of SSC(%) was investigated within the 27 storage days at $10^{\circ}C$ for fresh red kiwifruit treated with exogenous ethylene, whereas the carbon dioxide-treated fruit exhibited a greatly increased SSC after 64 days. The carbon dioxide-treated red kiwifruit maintained statistically(p<.01) higher levels of acidity compared to the control and the exogenous ethylene-treated ones during 41 days of storage at $10^{\circ}C$. The SSC/Acid ratio of fruit treated with carbon dioxide was significantly lower (p<.01) maintained than the other two treatments (ethylene-treated and control fruit)throughout the 75-day experiment. Based on the quality characteristics of postharvest red kiwifruit, it could be concluded that the carbon dioxide treatment significantly delayed the ripening process and maintained the market quality of harvested red kiwifruit, which can be a potential application for commercial use in the kiwi industry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1316-1323
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• 2016

The aim of this study was to evaluate proteolytic and antioxidant activities of fresh pineapple and kiwi juices extracted using a slow-speed masticating household juicer during low temperature storage. While over 90% of vitamin C and total polyphenols in both juices were retained after storage for 30 days at $-20^{\circ}C$, reduction of 56.8% for vitamin C and 31.9% for total polyphenols in pineapple juice were detected after storage at $4^{\circ}C$. In the case of kiwi juice, 32.9% of vitamin C and 22.4% of total polyphenols were lost. A high initial content of vitamin C in kiwi juice resulted in a slower reduction rate than that for pineapple juice. A similar result was obtained for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. Proteolytic activities of both juices were maintained efficiently with less than 10% loss during storage for 30 days at $-20^{\circ}C$. Protease stability of pineapple juice was better than that of kiwi juice during storage at $4^{\circ}C$, and the same result was obtained when boiled chicken breast was used as a substrate. From these results, when storing pineapple and kiwi juices, which are widely used as a natural meat tenderizer and digestive aid, cold storage at $-20^{\circ}C$ seemed to be more suitable for maintaining antioxidant and proteolytic activities than cold storage at $4^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.238-243
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• 2018

This study aimed to compare total phenolic, total flavonoid, and vitamin C contents, antioxidant capacities, and sensory characteristics of jangachi made from green kiwifruit (Actinidia deliciosa cv. Hayward) and golden kiwifruit (A. chinensis cv. Hort16A), which were cured with doenjang and kochujang. Golden kiwifruit had higher total phenolic, total flavonoid, and vitamin C contents, and antioxidant capacities than green kiwifruit. Jangachi of both cultivars of kiwifruit had generally higher total phenolic and flavonoid contents, and antioxidant capacities than fresh kiwifruit. Doenjang jangachi of kiwifruit had higher total phenolic contents and antioxidant capacities than kochujang jangachi. Jangachi made from golden kiwifruit cured with kochujang, following pretreatment with sugar solution, had the highest overall quality on sensory evaluation among jangachies tested herein. Together, our findings suggest that kiwifruit jangachi may serve as a good dietary source of phenolics and antioxidants.

• Journal of Mushroom
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• v.17 no.4
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• pp.235-240
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• 2019

In this study, we investigated the effects of pH, temperature, and salt concentration on protease activities in Hypsizygus marmoreus, and the ability of H. marmoreus extract to tenderize beef. In fact, H. marmoreus was shown to have higher protease activity than kiwi fruits. The pH of beef was dose dependently increased with addition of H. marmoreus extract. Cooking loss, cutting strength, and color value (L, a, b) were also dose dependently decreased with addition of H. marmoreus extract. In sensory assessments, H. marmoreus extract dose dependently enhanced perception of tenderness, flavor, and taste. In contrary, use of kiwi fruits as a meat tenderizer decreased positive perception of taste. The protease activitiy of H. marmoreus decreased sharply at pH < 2.0, and temperature > 50 ℃. Protease activity was relatively stable in NaCl concentrations ranging from 0-5 M, but incrementally decreased with increasing NaCl. These results suggest that, H. marmoreus extract can improve the texture and taste of beef.

• Food Science of Animal Resources
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• v.23 no.3
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• pp.193-199
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• 2003

In order to investigate the meat tenderizing effects of pear, pineapple and kiwifruit, crude protease was prepared from each fruit and treated with actomyosin in a single manner or mixed type in several combination. Actomyosin was incubated with various proteases for 24 hrs under three different pH condition, and its degrading performance was evaluated by the SDS-PAGE. Pear extract showed an active degrading activity for actomyosin at pH 5.3 and 7.0. But, little actomyosin degradation was observed at pH 8.0. Actomyosin was strongly degraded by the treatment of protease from pineapple at all different pHs(5.3, 7.0 and 8.0). Kiwifruit protease extract has shown actomyosin degradation activity 1hr after treatment at pH 5.3 and pH 7.0. Meanwhile, the mixture of pear and pineapple extracts(l:l, w/w) showed much more degradation than the results of singular manner treatment at pH 5.3 and 7.0. When the pear protease was mixed with kiwifruit protease(l:l, w/w), the performance of actomyosin degradation was similar to the results of each single protease treatment. When the mixture was made of pineapple and kiwifruit extracts, actomyosin degradation was almost the same as the result of treatment of pineapple protease only. When those three proteases were mixed together(l:l:l, w/w/w), actomyosin degrading activities was in time dependent manner at pH 5.3. In summary, pear protease can be used potentially as a meat tenderizer when it was mixed with pineapple or kiwifruit rendering proper tenderization of the meat.

• The Journal of the Korea Contents Association
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• v.21 no.7
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• pp.650-659
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• 2021

In this study, we aimed to investigate the effect of Chinese gooseberry (kiwi)-based products on the improvement of intestinal function and constipation. In this study, 21 participants with no underlying disease and complaining of subjective constipation symptoms were selected. Through a pre-experimental design, the main effects, including the colon stagnation score and colon transit time, were assessed after the consumption of Chinese gooseberry (kiwi)-based products. To evaluate the side effects of this product, a subjective constipation assessment test was performed to analyze the degree of constipation improvement at an individual level. The results for the main effects revealed that the number of constipation groups was statistically significantly decreased, and the colon stagnation score and colon transit time were also reduced. Additionally, the participants' subjective constipation assessment test revealed a significant improvement in both intestinal function and bowel activity before and after the consumption of Chinese gooseberry (kiwi)-based products. Similar to the previously known kelp-, lactobacillus-, and fiber-based products, we showed that Chinese gooseberry (kiwi)-based products exert a significant effect on the improvement of the intestinal function and constipation. Furthermore, the results of this study provide valuable information for the development of healthy food products in the future that can help improve bowel movement. Moreover, Chinese gooseberry (kiwi) used in this study is not a functional food and is easily accessible. However, this study has several limitations as it is based on a pre-experimental design. Therefore, studies on randomized experimental and control groups are needed in the future.

• Research in Plant Disease
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• v.24 no.1
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• pp.1-8
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• 2018

Bacterial diseases such as bacterial canker and bacterial leaf spot and fungal diseases such as gray mold, powdery mildew, side rot and leaf spots are major diseases damaging leaves of kiwifruit in Korea. In this review, we summarize symptoms and epidemiological characteristics of the major bacterial and fungal leaf diseases of kiwifruit and propose proper control methods of the diseases that can be practically utilized at the farmers' kiwifruit orchards in order to prevent the diseases on the basis of our research works and field experiences and important research products conducted during the last three decades in the world.

• Journal of Animal Environmental Science
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• v.10 no.2
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• pp.119-126
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• 2004

The protein in the extracts from the skins of pineapple and kiwi and the optimal conditions to hydrolyze blood, egg and gluten meals with them were investigated. Protein analysis by SDS-polyacylamide gel electrophoresis showed one protein band with 22 kd molecular weight in the pineapple skin extract, and Hve protein bands with 27 kd, 22.5 kd, 22 kd, 19 kd, and 14.4 kd molecular weight in the kiwi skin extract. The 22 kd protein in the pineapple skin extract is assumed to be bromelain, and the 27 kd protein in the kiwi skin extract is assumed to be actinidin, both are pretense. The optimal conditions for hydrolysis of blood, egg, and gluten meals we: 6-24 hours in time, $60^{\circ}C$ in temperature, and pH 4-pH 7.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.4
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• pp.581-585
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• 2003

Utilities of kiwi fruit powder prepared from post-mature kiwi fruit in bakery products such as bread and cookie were investigated. The characteristics of bread and cookie with different amounts of kiwi fruit powder were examined through physical measurement (color specific volume, crumb firmness, spread ratio, and extensibility) and seneory evaluation. In baking performance of frozen dough with kiwi fruit powder, $L^{*}$, $a^{*}$, and $b^{*}$ values of crust and specific volume gradually decreased as the concentration of kiwi fruit powder increased. Crumb firmness had significant difference compared to bread without kiwi fruit powder, and sensory characteristics of breads with kiwi fruit powder were more poor than bread without kiwi fruit powder. In a cookie with kiwi fruit powder although specific volume was not significantly different, the spread ratio of cookie and cookie toughness significantly decreased; furthermore, cookie extensibility significantly increased as an amount of kiwi fruit powder increased. Hardness and moistureness of cookies in sensory evaluation had a similar tendency as toughness and extensibility of cookies. Therefore, post-mature kiwi fruit could be utilized to improve the cookie qualities.ies.s.

• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.309-318
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• 2003

In order to improve the quality of low-grade seasoned ribs, kiwi powder, pear powder and phosphates were studied. To seasoned ribs, 0.1%, 0.3% or 0.5% of kiwi powder was added and their MFI(Myofibrillar Fragmentation Index) values were 341.4, 368.3 and 405.1, respectively. As the amount of kiwi increased, MFI value increased(p<0.001). Also, when 0.5%, 1.0% or 3.0% of pear powder was added to seasoned ribs, their MFI values were increased as the addition levels of pear powder increased. As the amount of kiwi and pear powder were increased, WHC(Water Holding Capacity) decreased(p<0.001). On the other hand, as the amount of phosphates added increased, WHC increased. In drip loss, as the amount of kiwi and pear powder increased, it increased. However, drip loss was decreased as the amount of phosphates increased. For meat color, ‘L’ values of pear treatment groups were similar to those of control and ‘a’ values were higher in the treatment groups of 0.1${\sim}$0.3% kiwi powder, 0.5${\sim}$1.0% pear powder and 0.3${\sim}$0.5% phosphate than those of control. In sensory evaluation, treatment group of 0.3% kiwi powder and 0.5% phosphate showed the highest values in juiciness, tenderness and acceptability among the treatments(p<0.01).