欧盟(EU)指令94/35/EC以及其他四项修正案: 96/83/EC、2003/1 15/EC、2006/52/EC和2009/163/EU限制了甜味剂在特定类型食品中的含量水平。欧盟委员会法规1129/2011列出了甜味剂在多种食品中的最高允许含量。因此,食品中这些甜味剂含量的测定对于确保产品质量的一致性也是非常重要的。
测定甜味剂最常用的方法是将HPLC与UV检测器联用。使用这样的配置可检测某些甜味剂,如乙酰磺胺酸钾、阿斯巴甜、糖精和纽甜。然而,由于不含发色团,甜蜜素和三氯蔗糖无法通过UV进行分析。但如果能使用单一方法通过质谱检测分析所有这些甜味剂,将是最理想的。为此,沃特世开发了ACQUITY QDa检测器,让食品和饮料科学家们可以将质谱检测技术结合到他们现有的色谱工作流程中。
ACQUITY QDa检测器不仅可以在单次运行中完成所有甜味剂的检测,还提高了分析的识别能力,因而在测定时无需保证所有化合物都实现基线分离。
沃特世(Waters™)UPLC™ H-Class系统和ACQUITY QDa检测器的结合对于食品和饮料生产商尤为有利,现在他们使用一种分析方法就能对产品中的甜味剂进行鉴定和定量。在本应用纪要中,开发了一种快速、可靠且高灵敏度的方法来分析食品和饮料样品中的甜味剂。
糖类以其甜味而著称,常被用于加工食品中以增加食品风味。由于过量摄
取糖类会影响人类健康,非营养性甜味剂常常作为糖类的替代品被用于
食品和饮料产品中,例如软饮料、袋装甜味剂、巧克力、乳制品和许多其他所谓的“减肥”食品。在很多情况下,可将多种甜味剂结合使用,为这些产品赋予总体的甜味。阿斯巴甜、糖精、乙酰磺胺酸钾、纽甜和三氯蔗糖是经过美国FDA批准的人造甜味剂1。源自南美植物甜菊的莱苞迪甙A和甜菊苷等甜味剂在美国也越来越受到欢迎。 2010年,欧洲食品安全局(EFSA)批准可将甜菊苷作为甜味剂使用。
欧盟(EU)指令94/35/EC以及其他四项修正案: 96/83/EC、2003/1 15/EC、2006/52/EC和2009/163/EU限制了甜味剂在特定类型食品中的含量水平。欧盟委员会法规1129/2011列出了甜味剂在多种食品中的最高允许含量。因此,食品中这些甜味剂含量的测定对于确保产品质量的一致性也是非常重要的。
测定甜味剂最常用的方法是将HPLC与UV检测器联用。使用这样的配置可检测某些甜味剂,如乙酰磺胺酸钾、阿斯巴甜、糖精和纽甜。然而,由于不含发色团,甜蜜素和三氯蔗糖无法通过UV进行分析。但如果能使用单一方法通过质谱检测分析所有这些甜味剂,将是最理想的。为此,沃特世开发了ACQUITYQDa检测器,让食品和饮料科学家们可以将质谱检测技术结合到他们现有的色谱工作流程中。 ACQUITY QDa检测器不仅可以在单次运行中完成所有甜味剂的检测,还提高了分析的识别能力,因而在测定时无需保证所有化合物都实现基线分离。
沃特世(Waters™)UPLC™ H-Class系统和ACQUITY QDa检测器的结合对于食品和饮料生产商尤为有利,现在他们使用一种分析方法就能对产品中的甜味剂进行鉴定和定量。
在本应用纪要中,开发了一种快速、可靠且高灵敏度的方法来分析食品和饮料样品中的甜味剂。
UHPLC system: |
ACQUITY Arc System |
Column: |
CORTECS T3, 2.7 µm, 3 x 100 mm |
Column temp.: |
40 °C |
Injection volume: |
2 µL |
Flow rate: |
0.55 mL/min |
Mobile phase A: |
Water with 0.1% formic acid |
Mobile phase B: |
Acetonitrile with 0.1% formic acid |
Runtime: |
8.5 min |
Time (min) |
Flow rate (mL/min) |
%A |
%B |
---|---|---|---|
Initial |
0.55 |
90.0 |
10.0 |
2.0 |
0.55 |
90.0 |
10.0 |
8.0 |
0.55 |
40.0 |
60.0 |
8.5 |
0.55 |
0.0 |
100.0 |
9.5 |
0.55 |
0.0 |
100.0 |
9.6 |
0.55 |
90.0 |
10.0 |
MS detector: |
ACQUITY QDa (Performance) |
Ionization mode: |
ESI-, ESI+ |
Capillary voltage: |
0.8 kV |
Probe temp: |
600 °C |
Cone voltage: |
15 V |
Sampling rate: |
2 points/second |
Acquisition: |
100–1000 m/z centroid |
SIR channels: |
See Table 2 |
Detector: |
Waters 2998 PDA Detector |
Wavelength: |
210–360 nm |
Sampling rate: |
10 points/second |
Analog channel: |
214 nm |
Stock solutions (1000 ppm) of each of the sweeteners were prepared in water.From these, a mixed stock of 25 ppm for 10 sweeteners and 50 ppm for REB A and sucralose was prepared in 2:3 (v/v) acetonitrile-water.From this, seven additional dilutions were made in 2:3 acetonitrile-water to produce eight levels of concentrations from 0.25 to 25 mg/L (ppm) for 10 sweeteners, and 0.5 to 50 mg/L (ppm) for REB A and sucralose.
本研究中共分析了七种不同的样品。.The samples included three table top sweeteners, a diet candy, a diet chocolate pudding, a diet soft drink and beverage standard.
将袋装甜味剂(约1 g)溶解于100mL水中,然后进一步稀释至两个浓度水平:1:20和1:10。将这三个稀释水平的样品进样,以涵盖此样品的不同甜味剂浓度。
The candy (5.29 g) and pudding (2.93 g) were dissolved separately in 100 mL water and diluted 1:10.The solutions were filtered through a 0.2 µ PVDF filter and injected.The diet soft drink was degassed through sonnication, filtered as above diluted 1:20 and injected.The beverage standard was diluted 1:20.
本研究中分析的八种甜味剂的化学结构如图1所示。这些甜味剂在反相色谱柱上进行分离并通过ACQUITY QDa检测器进行测定。这些甜味剂的保留时间、单离子扫描(SIR)质荷比(m/z)以及锥孔电压如表2所示。
The mass spectrum of each analyte was acquired using a Total Ion Current (TIC) scan (positive and negative).Results are shown in Figure 2.Please note the formate adduct for sucralose was observed.
Calibration curves and regression coefficients are shown in Figure 5.A quadratic fit with 1/x weighting was appropriate for these analytes.The correlation coefficient (R2) is greater than 0.996 for all compounds.Figure 6 is an overlay of the UV trace at 214 nm and the SIR channels at m/z 295.1 and 397.2 of aspartame and sucralose respectively.Sucralose being UV transparent does not appear in the UV trace but has a strong signal at m/z 397.2 showing the strength of mass detection augmenting UV.
The seven samples were prepared as previously described and analyzed in duplicate.The quantitation results are listed in Table 3.The first table-top sweetener contained sucralose (14.27 mg/g).The second table-top sweetener was found to contain aspartame (16.05 mg/g) and saccharin (4.17 mg/g).The third table-top sweetener listed Reb A as the main sweetener.However, besides the Reb A (27.72 mg/g), we note a small amount of stevioside (0.03 mg/g) was present although it is not listed as an ingredient.With the discrimination and sensitivity of mass detection, it was easily apparent that both of these co-eluting sweeteners were present in the sample, even though the stevoiside was present at a much lower level and was not labeled to be present.This is another example of the power of mass detection to detect low levels of analytes.The beverage standard was certified as 150 mg/L acesulfame K and 100 mg/L saccharin.Our values of 137.95 mg/L for acesulfame K and 97.66 mg/L for saccharin agree well here.
This application note has described a method for the separation, detection and quantification of twelve natural and artificial non nutritive sweeteners in less than 14 minutes (including equilibration time) using the ACQUITY Arc System coupled with the ACQUITY QDa Mass Detector.
ACQUITY QDa检测器使用单一方法即可分析具有UV透光性和UV不可透性的甜味剂,而且无论现有工作流程中是否配备UV检测器,此方法都能与之结合。质谱检测具有更高水平的分析物区分能力,并且无需不同质量数的分析物都实现基线分离。这有助于缩短方法开发时间,也无需为了验证化合物鉴定结果对单独的标准品进行进样。
720005017ZH,2017年6月