Antioxidant starch films containing sunflower hull extracts. (15th June 2019)

• Record Type: Journal Article
• Authors: Menzel, Carolin; González-Martínez, Chelo; Chiralt, Amparo; Vilaplana, Francisco
• Is Part Of: Carbohydrate polymers. Volume 214(2019)
• Page Start: 142
• Page End: 151
• Publication Date: 2019-06-15
• Subjects: Renewable packaging -- Physical properties -- Antimicrobial activity -- Molecular weight -- DPPH -- Chlorogenic acid; Polysaccharides -- Periodicals; Polysaccharides -- Periodicals; Polysaccharides -- Périodiques; Electronic journals; 547.78
• DOI: 10.1016/j.carbpol.2019.03.022
• Languages: English
• ISSNs: 0144-8617

Abstract

Highlights: Sunflower hull extracts were successfully incorporated into potato starch films. Aqueous MeOH produced fast and easy extraction of phenols from sunflower hulls. Starch films showed a significant antioxidant activity using DPPH* assay. Chain-length distribution of debranched amylopectin was not altered. Glycerol protected against degradation of starch during thermal processing. Abstract: This study explores the preparation of antioxidant starch food packaging materials by the incorporation of valuable phenolic compounds extracted from sunflower hulls, which are an abundant by-product from food industry. The phenolic compounds were extracted with aqueous methanol and embedded into starch films. Their effect on starch films was investigated in terms of antioxidant activity, optical, thermal, mechanical, barrier properties and changes in starch molecular structure. The starch molecular structure was affected during thermal processing resulting in a decrease in molar mass, smaller amylopectin molecules and shorter amylose branches. Already 1–2% of extracts were sufficient to produce starch films with high antioxidant capacity. Higher amounts (4–6%) of extract showed the highest antioxidant activity, the lowest oxygen permeability and high stiffness and poor extensibility. The phenolic extracts affected predominantly the mechanical properties, whereas other changes could mainly be correlated to the lower glycerol content which was partially substituted by the extract.