Carotenoids: as natural food colorant from Canna flowers

Abstract

Purpose – This paper aims to study carotenoids as a natural food colorant from Canna flowers. There is a growing demand for eco-friendly and non-toxic colorants, specifically for health-sensitive applications such as colours of food and textiles. Red Canna variety can be grown in normal garden situations and gives ample of flowers yielding good amount of natural colorant for both the purposes. Design/methodology/approach – In the present work, ultrasound extraction of natural colorant from Canna indica flowers has been studied. The use of ultrasound is found to have a significant improvement in the extraction efficiency of colorants obtained from dry and fresh Canna flowers in different mediums. Ultrasonic cavitational processing has twofold advantages, it is an eco-friendly and cost-effective process. Findings – The total carotenoid content in dry and fresh flower extract was found to be between 136.56 and 978.89 mg/kg. The assessment of antioxidant activity (AOA) in dry and fresh flower extract was found to be 5.78-78.33 per cent assayed by scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical and identified by electron paramagnetic resonance (EPR) studies. Research implications/limitations – The use of ultrasonication for the extraction of colorant has been the main feature and a step towards technological advancement in the area of finding newer method of efficient extraction of the colorant. Practical implications – The ease of extraction due to ultrasound waves has been the highlight. Originality/value – It is for the first time that the phytochemical data of red Canna flower and has been studied, the total carotenoid content and antioxidant activities of different extracts of Canna were measured. The extraction of natural dye from C. indica flowers using ultrasound has been found to have significant improvement in the extraction efficiency of the colorant obtained from flowers.