The effect of different coating materials on the coating of yeast (Saccharomyces cerevisiae) with the fluid bed coating method

Bread yeast is an important component in the formation of flavor and product volume in the bakery. However, it is very sensitive to moisture and can lose its activity by working even at very low moisture contents. Starting to work of yeast in flour mixes reduces the shelf life of the product, therefore it is not included in ready-made flour mixtures. The main purpose of this study is to make dry yeast form which can be used without any negative effect in ready flour mixtures by preventing moisture transmission and increasing shelf life. For this purpose, bread yeast was coated in fluidized bed by using edible film and coating technology, which is used in the food industry to increase the shelf life of foods and improve quality properties. In the first stage of this three-step study, film experiments were performed to determine the concentration of coating materials to be used in the coating of bread yeast in the fluidized bed. The second step involved determining the process parameters to be used during coating. In the last step of the study, using different combinations of 2 different fat (palm oil, sunflower oil), 3 different proteins (gelatin, Na-caseinate, egg white) and 5 different carbohydrates (pectin, alginate, carboxymethyl cellulose, maltodextrin, carrageenan) coating materials the bread yeast was coated with the Wurster (bottom) and top coating method in the fluidized bed. Analyzes of edible films and coated yeasts were evaluated together and the effect of different coating materials on the fluid bed coating of bread yeast was investigated. The results showed that the Wurster coating method was more effective in the coating of bread yeast in the fluidized bed and that the combination of palm oil-gelatin-pectin gave the best results in terms of low permeability, high yeast activity and high yeast solubility.