椰纤果生产中椰子水自然发酵过程成分及微生物群落变化

Changes of Chemical Composition and Microbial Community during Naturally Fermented Coconut Water Used in Nata de coco Production

为了解椰子水自然发酵过程中所发生的变化,跟踪研究椰子水自然发酵8 d过程中其主要理化成分及微生物数量和群落的变化。结果显示,可溶性固形物和还原糖变化主要出现在发酵前3 d,这期间p H也急剧下降,然后稳定在p H3.8左右;总酸含量在第2天达到第一个高峰,随后先下降,后上升;在观察结束时体系中的乳酸和乙酸含量分别为1.54 g/L和0.28 g/L;发酵初期,各种微生物迅速増殖,也在前3 d达到最大值,而后真菌数量逐渐减少,细菌数量始终维持在较高水平。在细菌体系中检测到了乳酸菌、醋酸菌、肠菌群、芽孢杆菌,其中乳酸菌和醋酸菌数量最多,且对成分变化有较大影响,而肠菌群和芽孢杆菌的存在也使得自然发酵椰子水存在一定安全隐患。本试验对于进一步了解自然发酵椰子水的菌相,并探寻其促进生产椰纤果的原因提供了理论依据,同时也为海南椰纤果行业走向安全、稳定、高产的生产模式奠定了良好基础。

The changes of the chemical composition and microbial community were investigated in naturally fermented coconut water used for nata de coco production. The soluble solids and reducing sugars decreased rapidly in the first 3 days, and meanwhile p H also decreased rapidly in the first 3 days, until to about p H 3.8.The total acids contents peaked on the 2nd day, then decreased firstly and went up afterwards, with the contents of lactic acid and acetic acid being 1.54 g/L and 0.28 g/L, respectively in the end. Various microorganisms grew fast and peaked on the 3rd day, and then the number of fungi decreased, while the number of bacteria remained at a higher level. Lactic acid bacteria, acetic acid bacteria,coliform, bacilli were detected in the bacteria, in which lactic acid bacteria and acetic acid bacteria being the main bacteria and greatly affected the components of the coconut water. The observation maybe helpful to elucidate the reason for enhancement of bacterial cellulose production by naturally fermented coconut water.