• Title/Summary/Keyword: rancidity development.

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Evaluation of the quality stability on the soybean flour depending on storage conditions

  • Park, Sung-Kyu;Son, Na-Young;Kim, Mi-Jung;Chung, Ill-Min
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.264-264
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    • 2017
  • Legumes are good sources of various nutrients. Among legumes, soybean and its flour are accessible foods to consumers. However, in case of soybean flour, there is a disadvantage of easily going rancid. Thus, this study aimed to investigate how the quality of soybean flour changes during storage according to the packaging materials and storage temperatures. The raw and roasted soybean flours were packed in two types of packaging, polyethylene (PE) and polypropylene (PP) film bags respectively, and stored at three different storage temperatures (4, 20, and $45^{\circ}C$) for 1 year. The acid value, conjugated diene value, peroxide value, p-anisidine value, thiobarbituric acid (TBA) value, lipoxygenase activity, and fatty acid content of raw and roasted soybean flours were measured at the point of starting storing, and after 1, 2, 4, 8, and 12 weeks of storage. The acid value of soybean flour was increased for 4 weeks and thereafter significantly decreased (p < 0.0001). The conjugated diene value was significantly increased after 4 weeks storage at $45^{\circ}C$ with PE and PP film bags (p < 0.0001). The peroxide value had no changes during 4 weeks storage at $45^{\circ}C$ with PE and PP film bags, and then those was dramatically increased after 8 weeks (p < 0.0001). The p-anisidine values in all of storage conditions were decreased after 4 weeks. Lipoxygenase activity was decreased at 12 weeks storage at $20^{\circ}C$ and $45^{\circ}C$ with PP film bags. Acid value had positive correlations with p-anisidine value (r = 0.30 and p < 0.0001) and lipoxygenase activity (r = 0.36 and p < 0.0001), and had negative correlations with conjugated diene value (r = -0.45 and p < 0.0001) and peroxide value (r = -0.25 and p < 0.001). Conjugated diene value had a high positive correlation with peroxide value (r = 0.76 and p < 0.0001), but that had a negative correlation with lipoxygenase activity (r = -0.51 and p < 0.0001). Peroxide value had negative correlations with p-anisidine value (r = -0.20 and p < 0.01) and TBA value (r = -0.15 and p < 0.05). The degree of reduction in fatty acid content of raw soybean flour was higher than the roasted soybean flour during the storage. Total fatty acid content had positive correlations with acid value (r = 0.45 and p < 0.0001) and p-anisidine value (r = 0.58 and p < 0.0001), but had a weak negative correlation with conjugated diene value (r = -0.19 and p < 0.01). This study showed how the rancidity of the raw and roasted soybean flours progressed during storage. Thus, our findings can be used as base data to do a further study of finding and developing more stable storage conditions of the soybean flour.

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Quality Characteristics of Samgyetang with Medicinal Herbs (전통 약용식물을 첨가한 삼계탕의 품질 특성)

  • Jung, Samooel;Kim, Tae-Kyung;Ku, Su-Kyung;Yong, Hae In;Lee, Kyung-Woo;Kim, Young-Boong;Choi, Yun-Sang
    • Korean Journal of Poultry Science
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    • v.46 no.2
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    • pp.95-103
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    • 2019
  • This study investigated the effect of traditional medicinal plants on the quality characteristics of Samgyetang breast meat and broth. The traditional medicinal plants used in this study were roots of Panax ginseng, Codonopsis lanceolata, Platycodon grandiflorum, Salvia miltiorrhiza, Adenophora triphylla, and Allium hookeri. There was no significant difference (P>0.05) in the moisture, protein, ash content, water holding capacity, and cooking loss of Samgyetang meat with the addition of traditional medicinal plants. The color values (lightness, redness, and yellowness) of Samgyetang meat and broth were significantly different (P<0.05); the 2-thiobarbituric acid reactive substances and shear force of Samgyetang meat were significantly different (P<0.05); and the pH, turbidity, and viscosity of Samgyetang broth were also significantly different (P<0.05) with the addition of traditional medicinal plants. In the overall acceptability of Samgyetang meat, the addition of S. miltiorrhiza showed the highest score compared to that of other treatments (P<0.05). Thus, the addition of traditional medicinal plants in the production of Samgyetang were found to affect the lipid rancidity beneficially with plant species when compared to Samgyetang with Panax ginseng. In conclusion, with the development of Samgyetang using S. miltiorrhiza, it will be possible to develop products with superior quality characteristics in antioxidant, shear force, and overall acceptability.

Development of Perilla frutescens with Low Levels of Alpha-Linolenic Acid by Inhibition of a delta 15 desaturase Gene (Delta 15 desaturase 유전자 억제에 의해 알파리놀렌산 함량이 낮은 들깨 육성)

  • Kim, Kyung-Hwan;Lee, Kyeong-Ryeol;Kim, Jung-Bong;Lee, Myoung Hee;Lee, Eungyeong;Kim, Nyunhee;Lee, Hongseok;Kim, Song Lim;Baek, JeongHo;Choi, Inchan;Ji, Hyeonso
    • Korean Journal of Breeding Science
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    • v.50 no.4
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    • pp.463-471
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    • 2018
  • Perilla is an oilseed crop cultivated in Korea since ancient times. Due to the high ${\alpha}-linolenic$ acid content in perilla, perilla seed oil can easily become rancid. ${\alpha}-Linolenic$ acid is synthesized by two enzymes, endoplasmic reticulum-localized ${\Delta}15$ desaturase (FAD3) and chloroplast-localized ${\Delta}15$ desaturase (FAD7) in vivo. In order to lower the ${\alpha}-linolenic$ acid content of the seed oil without disturbing plant growth, we tried to suppress the expression of only the FAD3 gene using RNA interference, whilst maintaining the expression of the FAD7 gene. Seventeen transgenic plants with herbicide ($Basta^{TM}$) resistance were obtained by Agrobacterium-mediated transformation using hypocotyls of perilla plants. The transgenic plants were firstly confirmed by treatment with 0.3% (v/v) $Basta^{TM}$ herbicide, and the expression of FAD3 was measured by Northern blot analysis. The ${\alpha}-linolenic$ acid content was 10-20%, 30-40%, and 60% in two, seven, and three of the twelve $T_1$ transgenic perilla plants which had enough seeds to be analyzed for fatty acid composition, respectively. Analysis of the fatty acid composition of $T_2$ progeny seeds from $T_1$ plants with the lowest ${\alpha}-linolenic$ acid content showed that the homozygous lines had 6-10% ${\alpha}-linolenic$ acid content and the heterozygous lines had 20-26% ${\alpha}-linolenic$ acid content. It is expected that the reduction in ${\alpha}-linolenic$ acid content in perilla seed oil will prevent rancidity and can be utilized for the production of high-value functional ingredients such as high ${\gamma}-linolenic$ acid.