优化色谱条件并测定巧克力食品中7种合成色素,有效分离柠檬黄和新红色谱峰.样品经聚酰胺粉吸附、解析、富集后,在波长为254 nm条件下,高效液相色谱仪分析,经二极管阵列器检测、甲醇+乙腈(1:1)和0.02 mol/L乙酸铵溶液梯度洗脱后,外标法定量.7种合成色素在质量浓度为0.5～20μg/mL范围内线性良好,相关系数为0.999 8～0.999 9,在0.500,2.000,10.000这3个质量浓度水平加标回收率为86.9％～98.3％,相对标准偏差为0.5％～2.1％,检出限范围0.06～0.44 mg/L.该色谱条件优化方式适用于巧克力食品中7种合成色素的检测.

建立全自动固相萃取-超高效液相色谱-串联质谱法同时测定大米中4种香精的分析方法.选用甲醇作为提取溶剂,经涡旋振荡和超声提取后,上清液加一级水稀释通过亲水亲脂平衡型固相萃取柱HLB净化,氮吹近干后补液过膜上机,使用Atlantis T3色谱柱分离,以甲醇-0.1％甲酸水为流动相.结果表明,4种香精在质量浓度为1～500 ng·mL-1时线性关系良好,相关系数R均大于0.999,平均加标回收率在80.1％～89.3％,RSD为1.7％～3.9％.该方法具有前处理简便、自动化、检测速度快等优点,适用于大米的批量检测.

通过测定食品中环己基氨基磺酸钠(又称甜蜜素)的含量,分析对比不同类别食品中甜蜜素的使用情况和添加趋势.采用《食品安全国家标准食品中环己基磺酸钠的测定》(GB 5009.97—2016)对东莞市市售、生产企业及餐饮中共1673批食品进行甜蜜素的测定,按照《食品添加剂使用标准》(GB 2760—2014)中的限量要求对测定结果进行判定,并对测得数据进行统计学分析.结果表明,总体合格率为99.9％,检出率为20.0％,其中,糕点、饼干、调味品、饮料、冷冻饮品、坚果及籽类和酱腌菜的检出率分别为4.7％、0％、5.3％、25.8％、52.0％、39.5％和72.1％.在不同类别的食品中,冷冻饮品和酱腌菜中甜蜜素的使用情况最为普遍(检出率>50％),酱腌菜中散装酱腌菜和标称为儿童/学生酱腌菜的添加水平更高(P<0.001),坚果及籽类中带壳熟制类的检出率和添加水平更高(P<0.001).本市食品中甜蜜素总体的使用情况良好,但仍存在超限量添加甜蜜素的情况,监管系统应继续加强相关食品的监督和管理力度,以保障市民的食品安全.

目的 建立分散固相萃取结合液相色谱-串联质谱法检测淡水鱼中9种磺胺类和3种喹诺酮类药物的分析方法.方法 淡水鱼肉样品用1％甲酸乙腈提取,提取液经盐析后取乙腈层,用分散固相萃取净化包净化,目标物用C18色谱柱(2.1 mm×50 mm,1.7μm)分离,采用0.1％甲酸水-乙腈作为流动相进行梯度洗脱,利用电喷雾离子源正离子多反应监测模式进行测定,内标法定量.结果 9种磺胺和3种喹诺酮类药物在1～50 ng/mL浓度范围内线性关系良好,相关系数均大于0.999.检出限和定量限分别为0.1～1.0μg/kg、0.5～5.0μg/kg,在3个不同浓度添加水平下的平均回收率为84.4％～114.6％,相对标准偏差为1.0％～7.8％(n=6).结论 该方法操作简单、快速、灵敏度高,适用于淡水鱼中常见9种磺胺和3种喹诺酮类兽药残留测定.

目的:建立一种QuEChERS超高效液相色谱-串联质谱快速筛查动物源性食品中恩诺沙星、环丙沙星、氟甲喹、孔雀石绿、隐色孔雀石绿、克伦特罗、沙丁胺醇、莱克多巴胺、氯霉素共计9种兽药残留情况的分析方法.方法:动物源性食品样品经粉碎处理后,1％甲酸-乙腈溶液提取兽药残留,QuEChERS净化提取液,经溶剂快速蒸发系统浓缩,50％乙腈-水溶液进行复溶,利用UPLC-MS/MS正负离子同时扫描,多反应监测(Multiplere Action Monitoring,MRM).结果:各组分在0.1～100.0 ng·mL-1范围线性关系良好(R>0.998),此方法的检出限符合国家标准需求,回收率为69.2％～115.4％,相对标准偏差为0.9％～12.7％.结论:该方法线性范围内线性、回收率、精密度符合要求,且简便、安全、高效,为常规兽药残留的筛查和检测提供了可靠的技术方法.

为探究啤酒对红烧老鹅品质的影响,采用色差仪和质构仪分析了啤酒对红烧老鹅色泽及质构的影响,通过顶空固相微萃取结合气相色谱-质谱联用(headspace-solid phase microextraction-gas chromatography-mass,HS-SPME-GC-MS)技术分析了啤酒对红烧老鹅挥发性风味物质的影响.结果表明:添加啤酒后对鹅肉的a*值和b*值均显著高于对照组的(p＜0.05),而L*值则无显著差异;与对照组相比,添加啤酒的鹅肉粘附性、胶粘性和弹性均显著低于对照组(p＜0.05),硬度和咀嚼性无显著变化(p＞0.05);添加啤酒后鹅肉中的挥发性风味物质增加6种酯类(辛酸乙酯、乙酸异戊酯、己酸乙酯、癸酸乙酯、乙酸乙酯和乙酸苯乙酯)、2种醇类(乙醇、糠醇)和1种烯烃类(罗勒烯).添加啤酒的鹅肉水分含量和pH值均显著低于对照组(p＜0.05),而粗脂肪含量和烹饪损失率则无显著变化(p＞0.05).

This study aimed to evaluate the difference in the characteristic flavor intensity of different lamb meats from different carcass cuts.The composition and content of free fatty acids in 15 lamb samples were determined by gas chromatography-mass spectrometry (GC-MS).Principal component analysis (PCA) was used to establish an evaluation model for the characteristic flavor intensity of lamb meat.The results showed that the contribution rates of the first three principal components were 56.654％,17.476％ and 14.287％,respectively and the cumulative contribution rate was 88.417％,which could not only accurately reflect the information on the original data,but also represent the basic information on free fatty acids.The correlation coefficient between the model results and traditional sensory evaluation was 0.939,indicating good consistency.Therefore,the evaluation model established by PCA was feasible and provided a new method for the evaluation of the characteristic flavor intensity of lamb meat.

In this paper, the effect of adding different amounts of white sesame powder (2%, 3%, 4% and 5%) into Chinese sausage on its physicochemical indexes, total free amino acid content, flavor, texture and antioxidant properties was studied.The total free amino acid content of sausage with sesame was significantly higher than that of the control group (P < 0.05)after air drying. Esters accounted for a higher percentage of the total volatile compounds, while aldehydes accounted for a significantly lower percentage when comparing the addition of sesame with the control group (P < 0.05). Moreover, the addition of sesame resulted in a significant drop in peroxide value (POV) and thiobarbituric acid reactive substances (TBARs)value compared with the control group (P < 0.05) indicating inhibition of lipid oxidation. Based on these results combined with sensory evaluation, the optimum addition level of sesame to Chinese sausage was 3%.