Improved incorporation and stabilisation of β-carotene in hydrocolloids using glycerol

In this paper, a novel method for the incorporation of the antioxidant beta-carotene in hydrocolloid matrices is presented, which consists on the use of glycerol as the vehicle for incorporation. This alcohol has been observed to greatly photostabilise the carotenoid molecule within the hydrocolloid matrices without greatly affecting the mechanical properties of the materials. The UV stability of beta-carotene in the different hydrocolloid films developed (including starch, soy protein, whey protein concentrate, gelatin and zein) has been studied using UV/visible spectrophotometry, colorimetry and Raman spectroscopy. Raman images of the materials were also generated in order to ascertain the dispersion of the antioxidant within the hydrocolloid materials and it was observed that beta-carotene was partially agglomerated in certain areas of the film, fact that could also contribute to enhance the stability of the bioactive molecule. (C) 2010 Elsevier Ltd. All rights reserved.