Influence of Treatment with Natural Phytoregulators on Purple Carrots (Daucus carota L.) during Cold Storage

Abstract

In this work, we investigated the effect of natural phytoregulators (i.e., methyl jasmonate and abscisic acid) on quality physicochemical parameters, carotenoid and anthocyanin content and antioxidant activity of purple carrots in storage at 5 °C for 21 days. As a result, study of the natural evolution of fresh-untreated purple carrots in storage exhibited increase in carotenoids (from 1.41 to 3.79 mg EβC g−1 DW) and stability of anthocyanins (2.18 vs. 2.23 mg ECGg−1 DW) but significant loss of organoleptic quality. Treatment with methyl jasmonate and abscisic acid resulted in similar or even higher carotenoid content (1.61 and 2.15 mg EβC g−1 DW for methyl jasmonate and abscisic acid, respectively) as compared with the value measured in fresh-untreated carrots before storage (1.41 mg EβC g−1 DW). In contrast to carotenoids, anthocyanins and antioxidant activity mostly decreased with the treatments. However, physicochemical parameters indicating organoleptic quality improved considerably, which was meaningful considering their importance in terms of consumer acceptance. These results reflect the slowing-down effect of natural phytoregulators on spoilage of purple carrots over storage. Optimization of this approach is scheduled to minimize anthocyanin losses. It can therefore be an interesting approach to extending purple carrot shelf-life with no need for artificial preservatives.