为加强蜂蜜真实性监测,从124份市面蜂蜜样品中筛选出51份δ13CH值(蜂蜜的δ13C值)小于δ13CP值(蜂蜜中蛋白质的δ13C值)的蜂蜜样品,采用元素分析-同位素质谱联用技术(EA-IRMS)、液相色谱-同位素质谱联用技术(LC-IRMS)以及液相色谱测定蜂蜜还原糖含量等多种检测手段,通过检测这些蜂蜜样品的系列稳定碳同位素比值、还原糖和蔗糖含量,对δ13CH值小于δ13CP值的蜂蜜样品进行了综合分析。结果表明:51份源于δ13CH值小于δ13CP值无法检测碳-4植物糖的样品,δ13CH值皆小于-23.5‰,2份样品还原糖含量低于60 g/100g,1份样品蔗糖含量超标,含量为7 g/100g,目前常规检测方法难以有效鉴评δ13CH值小于δ13CP值蜂蜜样品的真实性。将δ13CP-H(δ13CP-δ13CH)、δδ13CF-G(δ13CF-δ13CG)、δδ13Cmax(各类糖组分δ13C值的最大差值)以及寡糖检出等指标纳入综合鉴评,发现51份蜂蜜样品中的47份存在掺假掺杂嫌疑,所占比率高达92.16%,掺假掺杂主要以添加碳-3植物源转化产物为主,掺假原料可能是多类物质的复配组合。

In order to strengthen the monitoring of honey authenticity,51 honey samples with δ13CHvalue( δ13C value of honey sample) less than δ13CPvalue( δ13C value of protein in honey sample) were chosen from 124 specimens from food market. In the mean time,in order to have a comprehensive assessment of these honey samples, means of element analyzer-isotope ratio mass spectrometry( EA-IRMS),liquid chromatography-isotope ratio mass spectrometry( LC-IRMS) and liquid chromatography( LC) were used to detect the δ13C values,sucrose contents,C-4 plant sugar contents and reducing sugar contents. The results indicated that the δ13CHvalues in 51 honey samples were all less than-23. 5‰,reducing sugar contents of 2 honey samples were less than 60 g /100 g and sucrose content of 1 sample exceed limit of sucrose,which was 7 g /100 g. However,it is difficult to effectively assess the authenticity of these honey samples with δ13CHvalue less than δ13CPvalue by conventional detection methods. In our work,evaluation indexes,such as δ13CP-H,△δ13CF-G,△δ13Cmaxwere used for a comprehensive assessment. The results showed that 47 of 51 honey samples were considered to be adulterated honey,with the ratio of more than 92%. The samples were found to be adulterated by adding C-3 plant hydrolyzate,the adulterated material may be the compound of several carbohydrates.