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Pakteera Sripokar Yi Zhang Benjamin K. Simpson Egon Bech Hansen Suppasil Maneerat Sappasith Klomklao 《International Journal of Food Science & Technology》2021,56(12):6368-6375
Beardless barb is a common fish species used in fermentation of fish paste Ka-pi-plaa. Autolytic profile of beardless barb muscle showed the maximum autolysis was at 50 °C, at both acidic and alkaline pH values. With augmentation concentration of NaCl, autolytic activity slightly decreased. Endogenous proteinases isolated from fish muscle in crude extract forms were also characterised. The acidic proteinases had optimum activity at pH 3.0 and 50°C, and they showed higher proteolytic activity than the alkaline proteinases which were optimally active at pH 9.0 and 50 °C. Proteinases in peak at pH 3.0 were inhibited by pepstatin A, but those in peak at pH 9.0 were highly inhibited by PMSF, TLCK and soybean trypsin inhibitor, suggesting that both aspartic and serine proteinases were existed in beardless barb muscle. The proteinases were stable in pH range of 2.0-5.0 but unstable at the temperatures higher than 40 °C. NaCl suppressed the proteolytic activity, ATP activated the proteinase activity, while CaCl2, MgCl2 and CoCl2 exhibited no influence on the activity. The results implied that cathepsin D is the predominant proteinase responsible for autolysis in beardless barb. The findings were useful to improve the processing and qualities of Ka-pi-plaa product using beardless barb as raw material. 相似文献
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I. Revilla & M. L. González-San José 《International Journal of Food Science & Technology》2003,38(1):29-36
Summary The effect of the addition of four commercial pectolytic preparations on the visual characteristics (colour and turbidity) of red wines has been evaluated. The effect of both clarifying and colour extracting enzymes and the effect of different doses used, were evaluated and compared. All the red wines treated enzymatically, independent of the type of enzyme and dose, present chromatic characteristics which can be considered better than those of the control wines. Also, those wines treated with enzymes had greater stability during 2 years storage in bottles, in particular the turbidity was better than untreated wines. 相似文献
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浅议糯米酒的研制及系列化 总被引:5,自引:0,他引:5
经过对现在普遍采用的糯米酒生产工艺的改进,多次研制试验,最后确定的两种工艺为;(1)清质型工艺流程;(2)乳浊型工艺流程。合理的工艺条件参数为:淋饭温度30-35℃;多曲混合发酵,曲的用量为1%左右;糖化温度30-35℃,2-3d,最终糖度25g/100ml,加浆发酵温度0-5℃,灌装杀菌温度75-80℃,45min。 相似文献
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S. Genovés J.V. Gil P. Manzanares J.L. Aleixandre S. Vallés 《Journal of food science》2003,68(6):2096-2100
ABSTRACT: A recombinant Saccharomyces cerevisiae wine yeast strain expressing the Candida molischiana bgln gene encoding a β-glucosidase (BGLN) has been used to produce this enzyme. Shaking rate, pH, and aeration rate conditions have been optimized to obtain maximum activity to facilitate enzyme purification. The ability of the heterologous enzyme to efficiently release terpenols and alcohols from a Muscat wine glycoside extract and also directly from wine has been demonstrated. Terpenol glycoside content decreased by 50% after 1 mo of wine storage in agreement with results reported for the β-glucosidase produced by C. molischiana. 相似文献
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Kinema is a fermented soya bean food of Nepal and the hilly regions of North-eastern States of India. Generally, the fermentation is dominated by Bacillus spp. that often cause alkalinity and desirable stickiness in the product. The present study was undertaken in a limited number of commercial (market) kinema samples to test for the presence of foodborne pathogens and their properties. Bacillus cereus was present in numbers exceeding 104 cfu/g product in five of the tested 15 market samples. Enterobacteriaceae and coliform bacteria exceeded 105 cfu/g in 10 of the 15 samples. Escherichia coli exceeding 105 cfu/g was found in two samples. Staphylococcus aureus was not detected in any of the tested samples. Of 31 isolated typical and atypical strains of B. cereus, 18 representative strains were tested qualitatively for the ability to produce diarrhoeal type enterotoxin (BCET) using an Oxoid BCET-RPLA test kit. Overall, BCET was formed by 12 strains in BHIG (brain heart infusion broth +1% glucose), by seven strains on sterilized cooked rice, and by five strains on sterilized cooked soya beans. Semi-quantitative tests on BCET revealed that levels exceeding 256 ng/g soya beans, produced by single pure culture inoculation with the isolated B. cereus strains, were reduced to ≤ 8 ng/g by frying kinema in oil, a common procedure when making kinema curry. It was also shown in a mixed pure culture experiment that a kinema strain B. Subtilis DK-W1, is able to suppress growth and BCET formation by a selected toxin producing strain (BC7-5) of B. cereus. It is concluded that the traditional way of making kinema and its culinary use in curries is safe. However, for novel applications of kinema, safety precautions are advisable. 相似文献
10.
New HPLC Method to Determine Ethyl Carbamate in Alcoholic Beverages Using Fluorescence Detection 总被引:2,自引:0,他引:2
ABSTRACT: A new methodology to the quantification of ethyl carbamate (EC) has been developed. This method allows the analysis by HPLC of ethyl carbamate in samples of wine, fortified wine, and wine brandy, by a pre-column derivatization with 9-xanthydrol, and fluorescence detection. This does not require previous sample extraction or concentration. The method presents an average recovery of 96% among samples studied, a detection limit of 4.2μg/L, and an average intermediate precision of 6.3%. The comparison of the results obtained for EC analysis on the same wine brandy samples by GC/MS and HPLC are statistically indistinguishable with 97.5% probability. The results of the analysis of 42 samples are presented. 相似文献