Total carotenoid, anthocyanin, and sugar contents in sliced or whole purple (cv. Betasweet) and orange carrots during 4-week cold storage

Abstract

Minimally processed carrot products in finger or coin shapes are increasingly popular due to their convenience. The ‘BetaSweet’ carrot is a purple carrot with a high carotenoid and anthocyanin content, sweet taste, and juicy, crisp texture. This study was performed to investigate the changes in carotenoid, anthocyanin, and sugar of the sliced purple and an orange carrot during 4 weeks of cold storage at 2 °C or 4°C, simulating the transportation and marketing period. The purple carrot contained about 200–230 μg ·g⁻¹ fresh weight total carotenoid and there was a slight decrease in the total carotenoid content during the 4-week period at both temperatures. Anthocyanin and total sugar contents were about 400–500 μg · g⁻¹ and 70 mg· g⁻¹ fresh weight, respectively and did not change significantly at either temperature. The orange carrots, tested for comparison, contained about 100 μg·g⁻¹ total carotenoid and about 60 mg·g⁻¹ fresh weight total sugar, and showed similar trend as the purple carrots during cold storage. Transfer from 2 °C to 4°C at 2 weeks did not show significant changes in any of the parameters. Sliced carrots had about 10% to 15% less carotenoid content as compared to whole carrots, probably due to wound damage and the oxidation process. The content of nutritional compounds of the purple carrots harvested during April and June was similar to that obtained throughout the season, demonstrating that consistent quality products could be produced. Our study confirmed that the changes in quality of sliced purple carrots were minimal or negligible during the commercial marketing period of 2 weeks, if the product was handled and displayed at 4°C or below.