Stability of the Stevia-Derived Sweetener Rebaudioside A in Solution as Affected by Ultraviolet Light Exposure

• Autores: Jiewen Zhang, L. N. Bell
• Localización: Journal of food science, ISSN 0022-1147, Vol. 82, Nº 4, 2017, págs. 897-903
• Idioma: inglés
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• Resumen

  • Rebaudioside A is a natural noncaloric high-potency sweetener extracted from the leaves of Stevia rebaudiana. With rebaudioside A use increasing in foods, understanding the factors affecting its stability is necessary. This project evaluated the degradation rate constants of rebaudioside A in water, 0.1 M phosphate buffer, and 0.1 M citrate buffer at pH 3 and 7 as a function of ultraviolet (UV) light intensity (365 nm, 0 µW/cm2for dark conditions, 27 µW/cm2for low intensity, and 190 µW/cm2for high intensity) at 32.5 °C. Rebaudioside A stability was adversely affected by light exposure. The pseudo-1st-order degradation rate constants increased significantly (P< 0.05) with increasing light intensity in all solutions. Under dark conditions, rebaudioside A in phosphate buffers was more susceptible to breakdown than in water and citrate buffers at both pH levels. However, exposure to UV light resulted in rebaudioside A degradation occurring approximately 10 times faster in citrate than in phosphate buffers at both pH levels. The sensitivity of rebaudioside A to UV light was greater in citrate buffers than in water or phosphate buffers. The use of light-protective packaging for beverages containing rebaudioside A will improve its stability. Light exposure has an adverse effect on the stability of rebaudioside A. Proper formulations, light-protective packaging, and cool storage conditions are strategies that will improve the stability of rebaudioside A in food products.