Three different protein films to evaluate the changes in the quality of cheese samples

Biodegradable films are the focus of an increasing interest as they represent a natural and environmental-friend alternative to synthetic packaging materials. They might be defined as "thin layers to protect and extend the shelf life of food products that are also able to be consumed with the food materials". Proteins are among the most common materials for biodegradable packaging that are widely used. Phenolics are mostly found in fruits and they are significant antioxidants that are sufficient for human health. Therefore, this study is aimed to use three different sources of proteins: whey protein, soy protein and wheat gluten protein to investigate their properties and effects on sliced cheese samples' shelf life. Their combination with the grape juice addition was also tested. Glycerol was used as the plasticiser and the films are formed using suitable methods. Fixed amount of 15 g of protein films were added onto 3 -3.5 g cheese samples. The results of the study revealed that the films were elastic, adhesive, transparent and durable. Wheat gluten had the highest stretch and adhesive structure. Soy protein and whey protein films were found as the most protective since they decreased the moisture loss in the cheese samples. Grape juice added soy and whey protein films made the cheese samples more resistant to microbial growth. Combined usage of fruits with protein layers might be helpful to improve the cheese quality. Gluten protein film is the most viscous film amoung them. Whey protein based film is the most thickest film feature among them. The results of protein analysis on the films showed that the highest amount of protein was found in the whey based film and the lowest protein content was in the soy protein film.