Efficacy of dimethyl benzyl ammonium chloride and microbial contamination studies in a modern sugarcane milling unit in Thailand

Autor: R. Maungmontri, P. Weerathaworn, Nipa Milintawisamai, R. Kotrsri, C. Ngasan, A. Pliansinchai, W. Buttapeng, Suwanna Niamsanit
Rok vydání: 2009
Předmět:
Zdroj: Sugar Tech. 11:208-212
ISSN: 0974-0740
0972-1525
Popis: The modern milling process at Mitr Phuveing Sugar factory takes less than 10 min from cane stalk to mixed juice stage before the liming process. However, the microorganisms still affect sugar yield in the factory. The efficacy of dimethyl benzyl ammonium chloride (DBAC) and microbial contamination in the sugar cane juice from milling process were studied. The inhibitory effect of DBAC on the total microorganism, yeast and mold, and lactic acid bacteria in sugar cane juice was assessed aerobically by shaking at 45°C for 10 minutes. The concentration of sucrose and dextran were determined by High Performance Liquid Chromatography and Haze method of ICUMSA, respectively. The results showed that 2 and 6 ppm of DBAC cannot inhibit all kinds of microorganism within 10 minutes. The microbial population and dextran did not increase in sugar cane juice within 10 minutes. However, sucrose losses were noticed because of microbial utilization. Microbial population in the first, third and mixed juice in the milling process were monitored before and after sanitation by hot water and biocide application. The results showed that all kinds of microbial population varied with raw material. The microbial contaminations in some samples of sugar juice from the milling process were selected from plate count agar, malt extract agar and MRS agar medium containing 10% sucrose and identified by physiological and biochemical tests. The microbial contaminations found were mainly yeast: Saccharomyces cerevisiae, Candida guilliermondii and Candida tropicalis, and bacteria: Klebsiella pneumoniae, Lactobacillus fermentum, Enterobacter agglomerans and E. cloacae.
Databáze: OpenAIRE
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