黄骅虾酱的微生物学和理化性质研究

Study on Microbiological and Physicochemical Properties of Huanghua Shrimp Paste

为了评估黄骅虾酱的安全性以改进其传统生产工艺,对其微生物学和理化性质进行系统研究。使用选择性/鉴别性培养基,考察黄骅虾酱的菌落总数以及嗜盐性细菌、真菌、致病性肠杆菌、分解蛋白质细菌和乳酸菌的数量;使用分光光度法、高效液相色谱法等方法,测定黄骅虾酱的一般理化指标以及丙二醛、亚硝酸盐、挥发性盐基氮和生物胺含量。结果显示:大多数样品菌落总数(<3 lgCFU/g)合格;所有样品中均存在嗜盐性细菌;多数样品中未检出真菌,其余样品中真菌数量也较低(<2 lgCFU/g);大多数样品中检出致病性肠杆菌(<3.16 lgCFU/g);所有样品中未检测到乳酸菌和分解蛋白质的细菌。所有样品的食盐含量(<25 %)合格;pH值在7.0~8.0之间;水分活度在0.70~0.90之间;大多数样品的水分含量(65 %~80 %)超标;所有样品中均检出了丙二醛(<5 mg/kg)、亚硝酸盐(<0.50 mg/kg)、挥发性盐基氮(<450 mg/100 g)和生物胺(<550 mg/kg)。总之,家庭自制和工厂生产的黄骅虾酱都存在一定的安全性问题;比较而言,工厂生产的虾酱的安全性优于家庭自制的虾酱。

For evaluating the safety of Huanghua shrimp paste and improving its traditional process, the microbiological and physicochemical properties of Huanghua shrimp paste were systematically studied. The aerobic bacterial count, halophilic bacteria count, fungal count, pathogenic enterobacteriaceae count, lactic acid bacteria count and proteolytic bacteria count were investigated by the selection/differentiation media. The general physicochemical indicators and the contents of malondialdehyde, nitrate, volatile base nitrogen and biogenic amines of Huanghua shrimp paste were measured using spectrophotometry, high performance liquid chromatography and so on. The results showed that aerobic bacterial counts of most samples (<3 lgCFU/g) were up to standard;halophilic bacteria existed in all samples;fungi were not detected in most samples and those counts in the rest of samples were also low (<2 lgCFU/g);pathogenic enterobacteriaceae was detected in most samples (<3.16×102 lgCFU/g);lactic acid bacteria and proteolytic bacteria were not detected in all samples. In all samples, the content of sodium chloride (<25 %) was qualified, pH value was at the range of 7.0-8.0, and water activity was at the range of 0.70~0.90. The moisture content of most samples (65 %-80 %) exceeded the standard. Malondialdehyde (<5 mg/kg), nitrite (<0.50 mg/kg), volatile base nitrogen (<450 mg/100 g)and biogenic amines (<550 mg/kg) were detected in all samples. In general, in some extent, the problems of safety were existed in both homemade Huanghua shrimp paste and industrial Huanghua shrimp paste. By contrast, the safety of industrial shrimp paste was superior to that of homemade shrimp paste.