Details

Autor(en) / Beteiligte

• Bartholomees, Uria
• Struyf, Tom
• Lauwers, Olivier
• Ceunen, Stijn
• Geuns, Jan M.C.

Titel

Validation of an HPLC method for direct measurement of steviol equivalents in foods

Ist Teil von

• Food chemistry, 2016-01, Vol.190, p.270-275

Ort / Verlag

England: Elsevier Ltd

Erscheinungsjahr

2016

Quelle

Access via ScienceDirect (Elsevier)

Beschreibungen/Notizen

• •Steviol glycosides are a series of diterpene sweeteners used in food.•Their amounts present in food are converted to steviol equivalents.•Their common acid hydrolysate, isosteviol, can be measured fluorometrically.•When applied to different foods, steviol equivalents could be quantified directly.•Precision, accuracy, specificity, and sensitivity are reported. Steviol glycosides are intense natural sweeteners used in foods and beverages. Their acceptable daily intake, expressed as steviol equivalents, is set at 0–4mg/kg body weight. We report the development and validation of a RP-HPLC method with fluorometric detection of derivatized isosteviol, formed by acid hydrolysis of steviol glycosides. Dihydroisosteviol was used as an internal standard. Using this method, the amount of steviol equivalents in commercial steviol glycoside mixtures and different foods can be directly quantified. The method was successfully tested on strawberry jam, low-fat milk, soft drink, yogurt and a commercial mixture of steviol glycosides. Calibration curves were linear between 0.01 and 1.61mM steviol equivalents, with a quantification limit of 0.2nmol. The % RSD of intra-day precision varied between 0.4% and 4%, whereas inter-day precision varied between 0.4% and 5%, for high and medium concentrations, and between 3% and 8% for low concentrations. Accuracy of the analysis varied between 99% and 115%.