夏季车内存放时间对开封后瓶装饮用矿泉水中亚硝酸盐含量及菌落总数的影响

目的:探究夏季汽车内瓶装饮用矿泉水开封后的存放时间对水中亚硝酸盐含量及菌落总数的影响.方法:夏季将开封后的瓶装饮用矿泉水放置于汽车内,在第1 d、第3 d、第7 d和第14 d分别测定水中的NO2-含量及菌落总数.检验标准参考《食品安全国家标准饮用天然矿泉水检验方法》(GB 8538—2016)和《生活饮用水标准检验方...

Trend of Storage Time in Automobile on Nitrite Content and Total Bacterial Count of Bottled drinking Mineral Water after Unsealing in Summer

Objective:To explore the effect of nitrite content and total bacterial count of bottled drinking mineral water in automobile after unsealing in summer.Methods:In summer,the bottled drinking mineral water after open was placed in the car,and the changes of NO₂-content and total bacterial count in the water were measured on the 1st,3rd,7th and 14th day.Test standards:GB 8538—2016 and GB/T 5750.12—2006.Results:the total number of colonies increased slightly after the bottled drinking mineral water was stored in the car for 3 days,the geometric average of the total number of colonies was 7.5 CFU·mL^-1,and the content of NO₂-did not change significantly;after storage for 7 days,the total number of colonies and NO₂-content increased sharply,the geometric average of the total number of colonies was 95 CFU·mL^-1,and the NO₂-content was 0.125 mg·L^-1;after storage for 14 days,the total number of colonies and NO₂-content increased,the geometric average of the total number of colonies was 355 CFU·mL^-1,and the NO₂-content was 0.254 mg·L^-1.Conclusion:The experimental data show that when the bottled drinking mineral water after unsealing is stored in the vehicle for 7 days in summer,the number of colonies still meets the hygienic standard for drinking water(100 CFU·mL^-1),but it is close to the critical high value;the content of NO₂-does not meet the national food safety standard for drinking natural mineral water(0.005 mg·L^-1).Therefore,the storage time of bottled drinking mineral water after unsealing in the car in summer is close to or more than 7 days.It is not recommended to drink directly.