Cells immobilized in a starch-gluten-milk matrix usable for food production

A mixture of wheat flour and sour milk was treated according to the method of the traditional Greek fermented food “trahanas”, and was used as model cereal-based support (starch-gluten-milk matrix) for co-immobilization of lactic bacteria and yeast for potential use in food production. Cell immobilization was proved by scanning electron microscopy and by the efficiency of the immobilized biocatalyst for alcoholic and lactic repeated fermentations at various temperatures (5-30 °C). The stability of the system was good at all studied temperatures, revealing suitability for industrial applications. Finally, respectable amounts of lactic acid and volatile by-products were produced, revealing potential application of the immobilized biocatalyst in fermented food production or use as a food additive, to improve nutritional value, flavour formation or preservation time.