Amylases of kiwifruit were purified by ammonium sulfate precipitation, followed by Affinity chromatography (a-cyclodextrin sepharose 6B) and chromatofocusing (polyexchanger PBE94). Two different amylases were obtained in pure state and tentatively designated as Amylase I and II. Amylase I and II were found to be a single band when examined by electrophoresis. The specific activity of Amylase I and II was 1, 517 and 372-fold of the crude extract enzyme, respectively. Amylase I and II had molecular weights of 43, 000 and 40, 000; and showed the highest activity at pH 7.0, 55°C, respectively. Amylase I and II were stable at pH 6.0-8.0 and below 50°C. The Km values for soluble starch of Amylase I and II were calculated to be 9.5 and 17.9 mg/ml, respectively. Both activities of the enzymes were inhibited by Hg²⁺. Qualitative thin-layer chromatographic analysis on the starch solution digested two enzymes revealed specificity of products. Amylase I produced a maltopentaose at first and later produced maltotetraose, maltotriose and maltose, while Amylase II produced maltotetraose, maltotriose and maltose from soluble starch.

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Heat treatments for processing nuts are essential operations in order to prolong their shelf life and also to develop distinctive flavor and taste. However, the effects of such heat treatments on lipid-rich products such as macadamia nuts and cashew nuts have not been studied. In this study, effects of roasting on lipid classes and their fatty acid composition were found to be negligible when fully mature nuts were successfully dried and roasted to an acceptable level of moisture content. The roasting process, therefore, seems to involve very little changes in the amount of lipids for developing favorable taste and flavor.

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While a Mesona procumbens Hemsl extract cannot induce gelation alone, it is known that gelation can be enhanced by the addition of starch dilute solution. The present study investigated the relationship between enhanced gelation and the polysaccharides of this plant that are believed to be involved in dynamic modulus. Mesona procumbens Hemsl contains large quantities of saccharides, and minerals such as K, Ca and Mg. Of the polysaccharides extracted from 5% sodium hydrogen carbonate solution exhibited enhanced gelation. From the result of fraction of cell wall polysaccharide, it was estimated that polysaccharide was solubilized in alkali solution, contained glucose, arabinose and xylose as neutral saccharide in the leaf and mainly contained arabinose in the stem. The molecular weight of the polysaccharides extracted using sodium hydrogen carbonate solution ranged from 14, 000 to 16, 000. Of the alkali fraction mainly contained with molecular weights of 15, 000-38, 000. These findings suggest that the molecular weight of polysaccharides in Mesona procumbens Hemsl that are involved in enhanced gelation is very small.

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Changes in lipid compositions in Japanese honewort (Cryptotae japonica Hassk) seed during growth at 56 days (8 weeks) at 25°C were studied. The total lipids content (g/100 g dry seeds) was decreased during growth, and it was remarkably during germination. Triacylglycerol content as a main component of total lipids was significantly decreased during germination. In glycolipid fraction, ASG, SG contents were decreased during growth, and MGDG, DGDG contents (g/100 g dry matter) were relatively increased. Main fatty acid in total lipids in seed were 18 : 1 n 9, 18 : 2 n 6, 18 : 3 n 3, 16 : 0 acids. The content of 18 : 3 n 3 acid in total lipids was gradually increased during growth. On the other hand, 18 : 1 n 9 acid was decreased relatively. Especially, increase of 18 : 3 n 3 and 16 : 3 n 3 acids contents in glycolipid fraction were notable.

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Chili (Capsium annuun L.) is a popular agriculture product in tropical areas. The pickled peeled chili especially is a new product in the eastern Asia area. However, the addition of preservatives and the extension of the shelf-life of the product are major problems during processing. In this paper, two steps of preheating were used to improve the quality. Firstly, the raw material was heated at 50°C for 60 minutes, and then fried at 200°C for 25 seconds. After peeling, some seasoning was added to the crisp chili, adjusted the pH to 4.3 and pasteurized at 90°C for 15 minutes. The total bacterial count, including yeast, mold and lactobacillus, were less than 25 CFU/g during one-year storage.

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