assessment of physiochemical and antioxidant characteristics of bell pepper (capsicum annuum l.) using principal component analysis by guar, xanthan gum, and carboxymethyl cellulose as edible coatings

Extending the shelf life of vegetables can be achieved using edible, environmentally friendly coatings. in this study, bell peppers were coated with guar (gu) gum, xanthan (xan) gum, or carboxymethyl cellulose (cmc) at concentrations of 0.5, 1, and 1.5 %. uncoated bell peppers served as the control. all samples were stored for 28 days under walk-in storage conditions (8-10 °c, 85% relative humidity, and darkness). results showed that as storage time increased, signs of disease infection and water loss in the bell pepper fruits also increased. additionally, levels of organic acids, vitamins, phenols, and antioxidants declined during storage. overall, the coatings improved key marketability traits, including fruit firmness, total soluble solids (tss), and organic acid content, all of which contribute to flavor and taste. the extent of fruit skin shrinkage varied depending on the coating type. according to a biplot analysis, carotenoid content, firmness, and tss were substantially improved by xan gum at 1 % and cmc at 0.5 and 1 %. in contrast, starch, chlorophyll, phenol, and vitamin c contents increased by xan gum at 0.5 % and gu gum at 0.5 and 1 %. in conclusion, the gu gum coating at 1 % was the most effective treatment for enhancing postharvest quality and maintaining the shelf life of bell peppers. toxicological assessment remains essential for the continued development of edible coatings based on natural gums with suitable physical properties.