The present invention is to provide a natural bactericide which may be applied to a food material sterilization operation, is purely natural without containing chemical additives, and may be applied safely and healthily, and a preparation method thereof. The technical means is as follows: In the product aspect, the natural bactericide is characterized by containing a reactant body with isothiocyanates, wherein the reactant body is prepared from white radish juice extracted from white radish, in cooperation with a water body and mixed for reaction according to a weight ratio. As to the preparation method, the preparation method is characterized by comprising four steps of: preparing retrieving extracting and filling, in particular, the retrieving step cell walls of the white radish are physically disrupted by an retrieving machine to release sulfo-glucoside and myrosase, a hydrolysis reaction is produced when used in cooperation with the water body, and isothiocyanates may be massively produced gradually.本發明在於提供一種能應於食材殺菌作業上,純天然且無化學添加物,能安心健康應用的天然殺菌劑及其製法。其技術手段:為產品方面,其特徵在於:所述天然殺菌劑包含有一具有異硫氰酸酯類體的反應劑體,其是由白蘿蔔所提取出的白蘿蔔汁液體,配合水體,依重量配比所混合反應而成;關於製法方面,其特徵在於包括備料步驟、提取步驟、萃取步驟、及填裝步驟等四步驟,重點在於提取步驟須以提取機,以物理性的方式,將白蘿蔔的細胞壁破壞,釋出硫化葡萄糖苷和芥子酶,配合水體產生水解反應,並逐漸大量生成異硫氰酸酯類體。1‧‧‧反應劑體11‧‧‧異硫氰酸酯類體100‧‧‧天然殺菌劑D‧‧‧第二容器
