Functional potential and food safety of fresh-cut ‘Paluma’ guava under edible coatings

Abstract

Guava is a fruit rich in antioxidants and its value can be enhanced by fresh-cut processing, which increases convenience for consumption. The objective of this study was to evaluate the changes in bioactive compounds, total antioxidant activity (TAA) and microbial quality in slices of fresh-cut (FC) ‘Paluma’ guava coated with chitosan at 2% (Q), calcium chloride at 1% (CC), calcium chloride at 1% + sodium alginate at 1% (CC + A), calcium chloride at 1% + chitosan at 2% (CC + Q), and control (T - without coating). Coated slices were packed in trays, wrapped with PVC film and kept at 3 ± 1 °C and 75 ± 4% RH for 12 days and evaluated for ascorbic acid, lycopene, β-carotene, total extractable polyphenols (TEP), and TAA by ABTS+- and DPPH . Ascorbic acid content of slices did not differ by coatings, but TEP was higher in slices coated with Q. The TAA by DPPH was higher in slices coated with Q, however, by ABTS+- it was higher in those coated with Q, CC and CC + Q. No thermotolerant coliforms or Salmonella were detected in FC guava from any treatment. However, slices coated with Q showed the lowest counts of total coliforms and molds and yeasts. Therefore, the application of Q coating provided microbiological safety to FC guava, still maintaining the levels of bioactive compounds and TAA superior to the control slices, which can characterize this as a healthy FC product, with superior functional potential.