Octenyl succinylated potato starch-based film reinforced by honey-bee products: Structural and functional properties

Edible films were developed from native or octenyl succinylated potato starches and extracts from the following honey-bee products: multifloral honey, buckwheat honey, bee-pollen, bee-bread or propolis. Pasting and rheology properties of film-forming suspensions as well as structural characteristic and physical properties of the produced films were studied. The results showed that esterified starch and the honey-bee extracts (HBE) changed film properties in a different way, depending on the type of the extract. The pasting and rheological properties were improved as a result of both starch esterification and incorporation of the HBE. The FTIR-ATR spectroscopy of films indicated that some molecular interactions between the starch and the HBE may have occurred. The films made from the esterified starch showed significantly lower tensile strength, elasticity, thermal transition parameters (enthalpy - ΔH and onset - To, peak - Tp, end - Te temperatures), as well as higher swelling as compared to the native starch films. All films were characterized by a high structural integrity, however films based on esterified starch and reinforced with HBE exhibited a rough and folding surface. Bee-bread and propolis extracts seem to be the most promising HBE for production of films due to the ability to reduce solubility and thermal transition parameters as well as to improve mechanical properties of the films.