Guar gum and chitosan-based composite edible coating extends the shelf life and preserves the bioactive compounds in stored Kinnow fruits

Abstract

The present investigation aimed to elucidate the effects of chitosan (CH) and guar gum (GG) based composite edible coating on physicochemical quality and storability of Kinnow fruit under ambient conditions. Composite coating materials were prepared by using tamarind (TAM) seed starch and jackfruit (JACK) seed starch with CH and GG separately. The results indicated that GG + TAM coated fruits maintained significantly (P ≤ 0.01) lower physiological losses in weight (PLW) (3.12 %), decay incidence (0.83 %), and respiration rate (13.57 ml CO₂ kg^-1 h^-1) compared to control. The reduced activity of pectin methylesterase (PME) (0.97 μmol min^-1 g^-1 FW) and lipoxygenase (LOX) (1.97 μmol min^-1 g^-1 FW) were noted in GG + TAM coated fruits. Also, the GG + TAM coated fruits retained higher fruit firmness (6.77 N), titratable acidity (TA) (0.94 %), ascorbic acid (AA) (27.83 mg 100 g^-1), total phenols (213.05 mg GAE 100 g^-1 FW), antioxidants activity (23.57 μmol TE g^-1) along with higher sensory score over the control. Based on findings, it can be concluded that GG + TAM coating could be gainfully utilized for prolonging the shelf life of Kinnow fruits up to 25 days without losing desirable quality traits at ambient storage.

Keywords: Antioxidants; Decay incidence; Hydrocolloids.