食品链微生物学计算β-葡萄糖醛酸酶阳性大肠杆菌数的水平方法.第3部分:用5-溴-4-氯-3-吲哚-β-D-葡萄糖醛酸测定最可能数Microbiology of the food chain - Horizontal method for the enumeration of beta-glucuronidase-positive Escherichia coli - Part 3: Detection and most probable number technique using 5-bromo-4-chloro-3-indolyl-β-D-glucuronide