高效液相色谱法同时测定面包糕点中苯甲酸(钠)、山梨酸(钾)、安赛蜜、糖精钠和脱氢乙酸(钠)的含量

面包糕点中的苯甲酸(钠)、山梨酸(钾)和脱氢乙酸(钠)、安赛蜜和糖精钠经溶解、离心、过滤后,采用高效液相色谱法同时测定,样品标准加入回收率分别为94.2%～101.6%、93.6%～102.7%、90.8%～99.1%、92.5%～102.3%、91.1%～99.5%,RSD分别为1.8%～10.3%、1.5%～11.2%、1.2～9.5%、1.2～6.8%、1.7%～10.9%。

关于GB/T5009.29-2003高效液相色谱法对食品中山梨酸、苯甲酸的测定的探讨

对国家食品卫生检验方法 GB/T 5009.29-2003《食品中山梨酸、苯甲酸的测定》进行探讨。采用高效液相色谱法同时对面包样品的山梨酸、苯甲酸含量进行测定:得出苯甲酸含量测定结果平均RED为0.3,回收率为97.8%,山梨酸测定结果平均RED为0.2,回收率为98.1%;并对实验中出现的状况进行分析解决。

高效液相色谱法同时测定食品中安赛蜜、苯甲酸( 钠) 、山梨酸( 钾) 、脱氢乙酸( 钠) 和糖精钠

目的研究一种快速、准确、简单的高效液相色谱法同时测定食品中安赛蜜、苯甲酸(钠)、山梨酸(钾)、脱氢乙酸(钠)和糖精钠等5种添加剂。方法根据样品类别选择不同的前处理方法,以甲醇∶乙酸铵(pH=6.8)=5∶95(体积比)作为流动相,利用二极管阵列检测器(DAD)检测样品的特征吸收光谱图,以保留时间定性,外标法定量分析。结果5种标准品的最大吸收波长分别为安赛蜜225.89 nm、苯甲酸226.87 nm、山梨酸254.97 nm、糖精钠268.68 nm、脱氢乙酸232.45 nm和292.62 nm。在1μg/ml^200μg/ml浓度内具有良好的线性关系(r=0.9999),检出限为0.001 mg/g^0.005 mg/g,回收率为96%~98%,相对标准偏差为0.19%~1.0%。结论本方法利用NaOH和乙酸锌作为蛋白共沉淀剂,能有效去除样品中蛋白,提高了方法的灵敏性,能快速实现各类食品中5种添加剂的同时检测。

高效液相色谱法同时测定食品中苯甲酸(钠)、山梨酸(钾)、安赛蜜、糖精钠和脱氢乙酸(钠)的研究

探讨采用高效液相色谱法同时测定食品中的苯甲酸、山梨酸、安赛蜜、糖精钠和脱氢乙酸五种食品添加剂含量的方法。样品经超声提取,采用C18色谱柱,以0.02mol/L乙酸胺一甲醇为流动相,用二极管阵列检测器于230 nm波长处检测。该方法灵敏度高,重现性和选择性好,回收率高,易于操作,是检测食品中5种添加剂的有效定量方法。

Study on Preservative Formula and Shelf Life of Cantonese Style Moon Cakes

To ensure the safety of consumers, prolong the shelf life of moon cake and reduce the cost of manufacturing and marketing enterprises, the optimization of preservative formula and the shelf life of cantonese style moon cake were studied. Through single and compound formula preservative test, the results showed that potassium sorbate and sodium dehydroacetate could inhibit the microorganisms in the moon cake, but the inhibitory effect of sodium dehydroacetate was stronger than that of potassium sorbate; and the combination of potassium sorbate and sodium dehydroacetate had a synergistic effect, and the best formula is ＇potassium sorbate 0.44 g/kg mixed with sodium dehydroacetate 0.38 g/kg. A batch of moon cake was prepared with the best preservative formula, then the total number of colonies, molds and coliform group in the samples were detected by random sampling at irregular intervals. The total number of molds exceeded the limit on the 187^th d, and it indicated that the shelf life of the product was 187 d. Compared with the conventional 15-day shelf life, this research greatly prolongs the sheff life of cantonese style moon cake, and cut down the cost of moon cake enterprises. It is worthy of popularization and application.

食品防腐剂影响微生物指标检验结果的机制

选择卫生部门与相关检查单位所提供的含防腐剂食品样品416份,采用多种培养基试剂进行检验测试,分析防腐剂苯甲酸(钠)、山梨酸(钾)对微生物真菌计数和菌落总数的影响。结果表明,防腐剂对菌落总数和真菌计数检测结果的影响随着防腐剂浓度的增加更显著,苯甲酸(钠)和山梨酸(钾)2种防腐剂菌落总数并未显著性差异,山梨酸(钾)对真菌计数产生的影响高于苯甲酸(钠)。

Development of Chitosan Film Incorporating Garlic Oil or Potassium Sorbate as an Antifungal Agent for Garlic Bread

Chitosan is a biopolymer material. Mechanical, physical and barrier properties of different chitosan films incorporating garlic oil at 25, 50 and 100 μL/g chitosan or potassium sorbate at 25, 50 and 100 mg/g chitosan as antifungal agents were studied. Addition of garlic oil or potassium sorbate into the films did not alter their color except at the highest concentration of garlic oil which resulted in a more yellowish film. Garlic oil reduced film strength and elongation but it had no effect on water vapor transmission rate. Potassium sorbate reduced film strength and water vapor transmission rate, but it increased oxygen transmission rate. Films containing garlic oil or potassium sorbate was used to wrap around garlic bread to evaluate its shelf life. The development of mold on the bread surface was observed daily. The results showed that garlic bread wrapped in chitosan film incorporating garlic oil had 23 days shelf life, compared with only 7 days shelf life of garlic bread without wrapping. Garlic bread wrapped by film containing potassium sorbate had 13 days shelf life. Garlic breads wrapped by the films incorporating either garlic oil or potassium sorbate were acceptable in terms of sensory evaluation.

食品防腐剂对菌落总数检测影响的研究

研究几种常用食品防腐剂对风味饮料、果汁饮料菌落总数检测可能存在的影响。结果表明,食品防腐剂在使用限量范围内,样品菌落总数检测结果与对照样菌落总数检测结果没有显著性差异,因此可以认为,食品防腐剂不会对菌落总数检测产生影响。