New discovery: Australian green apple peel can be used to produce natural edible film

New discovery: Australian green apple peel can be used to produce natural edible film

Time:2019-02-22 Hits:
A new study shows that the extract of the Australian green apple (Granny Smith) peel can be used to produce edible films.To improve the quality and preservation of food during processing and / or storage, the study has been published in the International Biomacromolecular Impurity.
Researchers at the University of La Plata in Argentina (UMLP) and Columbia University Universidad de Sucre pointed out that,The aqueous extract or ethanol extract of green apple peel has different effects on the methyl cellulose film, and the ethanol extract obtained by freeze-drying is an active substance having good barrier properties and mechanical properties.
On the other hand, the presence of sugar in the aqueous extract produces plasticization which increases the flexibility of the film.The methylcellulose film to which the green apple peel extract was added proved to be a transparent system whose properties depend on the type and content of the extract.The active and functional ingredients extracted from the green apple peel have antioxidant properties and can be added to the hydrocolloid matrix as a polyphenol, which can be used in the food field.
Edible film formulations containing active ingredients will be a strategy to provide nutrition using agro-industrial by-products and allow the development of new types of coatings for functional foods.Scientists point out that the apple juice and apple dry industries produce large amounts of agricultural industrial waste, which is rich in polyphenols, vitamins and minerals and can be used as a functional ingredient.Compared with other varieties of apples, Australian green apples are less sensitive to browning and have higher hardness and juiciness. Therefore, this variety is most suitable for industrial processing.
The study used methylcellulose (A4M, Methocel) supplied by Colorcon Argentina, and the researchers used an extract of apple peel or an ethanol extract obtained by lyophilization to prepare an edible film. The results show that the water extract reduces the tensile strength of the film and also increases the elongation at break.
On the other hand, the effect of the ethanol extract on the mechanical properties of the methylcellulose membrane is small, mainly because the plasticization of the sugar is absent in the aqueous extract.An edible film preparation prepared by freeze-drying apple peel ethanol extract is an effective alternative to obtaining a material having good barrier properties and mechanical properties.There is also no need to add additional plasticizer to the matrix, which can result in a substantial shift in the glass transition temperature of the material and a deterioration in mechanical properties.