Recent developments in beetroot pigment extraction techniques and their food applications

Abstract

Beetroot is well known for its deep red-purple colouring pigments called betalains. Betalains also found its application in the preparation of functional foods and drinks. Therefore, extraction of pigments with higher recovery and stability is the prime need for the industry. Conventional extraction techniques such as maceration, grinding or pressing have reported low yield of betalains and required large volume of solvent and energy. On the other hand, emerging technologies such as ultrasound, microwave and pulse electric field techniques are highly efficient processes and achieved higher recovery. In this regard, this review provides an in-depth discussion on the various extraction methods and factors affecting the stability of betalains using conventional and emerging technologies. The recent applications of pigments in various food system were also presented. Finally, challenges and future prospects of extraction and application of beetroot pigment identified and discussed.