High intensity sweetener analysis

Since the publication of the first edition of this book, a few more validated methods for the analysis of soft drinks ingredients have been documented. When the first edition was published in 1998, only a handful of methods for the analysis of soft drinks ingredients had been collaboratively tested in the Association of Official Analytical Chemists (AOAC) official methods manual, and only two of these were modern HPLC approaches. At that time, no methods could be found in the British Standards catalogue. Inspection of the British Standards website (http //www.bsi-global.com) now shows that there are two standardised approaches for the analysis of high-intensity sweeteners in soft drinks, both of which use HPLC. This overall lack of standardisation of methods is probably because a soft drink s matrix is relatively straightforward, without many of the problems associated with other areas of food analysis, and so the industry has not felt the need to standardise the test methods. 

Although sugars are found in juices, the high-intensity sweeteners are not. However, they are often used in juice-based drinks or nectars, and here it is important to ensure that there is resolution of the sweeteners of interest from the compounds naturally present in fruit juices. This can be a particular problem in drinks with a high juice content as naturally occurring polyphenolic materials in the juice can disturb the analysis. 

Acesulfame K was intr oduced as a high-intensity sweetener at around the same time as aspartame. It too is much sweeter than sucrose but is also stable under the low pH conditions of soft drinks. Its analysis in a soft drink is relatively straightforward and an HPLC procedure is given by Grosspietsch and Hachenburg (1980). 

Sample preparation Sample preparation for the determination of high-intensity sweeteners is relatively simple. Carbonated soft drinks are degassed prior to analysis. Liquid beverages and tabletop sweeteners are diluted or dissolved in water. Sweeteners in complex foods are extracted with water or an appropriate solvent. Then, the extract can be clarified, centrifuged, or cleaned by using solid-phase extraction techniques. 

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