Changes in Some Physical and Nutritional Properties of Tarhana, a Turkish Fermented Cereal Food, Added Various Phytase Sources

The effects of three different levels of baker's yeast, barley malt flour and a microbial phytase supplement have on fermentation loss, colour, pH, total and HCl-extractable ash (HEA) and HCl-extractable phosphorus (HEP) ratio of Turkish tarhana were investigated. Fermentation loss, expressed as dry matter loss, was used for estimation of tarhana processing yield, including the fermentation, drying and grinding processes, and found on average to be 12.96%. Fermentation loss provided a proportional increase in the total ash and phosphorus content of the samples and pH decreased by adding microbial phytase. HEA and HEP content as a measurement for mineral bioavailability increased from 68.32% (dough) to 82.07% (tarhana), and from 60.45% to 83.63%, respectively, during the production process. Additions of yeast, barley malt and phytase significantly raised the HEA and HEP content ( p 0.01). Among the phytase sources, yeast was the most effective additive on the ash and phosphorus extractability. The combination of 2.5% yeast and 4% malt was the optimum treatment to obtain a low fermentation loss and high HEA and HEP. Increasing HEA and HEP values could mean higher bioavailability of minerals bound by phytic acid.

Effect of transglutaminase on some properties of cake enriched with various protein sources

The effect of transglutaminase (TG) enzyme addition (0% and 0.09%) on batter and cake properties, prepared with different protein sources (nonfat dry milk [NFDM], soy flour, and soymilk) and flour types (type A with 11.4% protein and type B with 8.6% protein), was investigated. Specific gravity and pH of cake batters were determined, and physical and chemical analysis of the cake samples was performed. Soy products improved cake weight, volume, softness, protein, and fat contents. NFDM increased the crust redness and crumb lightness more than the other protein sources. TG enzyme addition affected the volume, softness, crust, and crumb color of the cake samples significantly (P < 0.05). The combination of TG enzyme and flour B with lower protein gave more puffed, symmetrical, and softer cake samples. TG had a potential application with different protein sources in cake production. Especially interactions between TG with soy flour and TG and wheat flour with high protein content were important in cake formulations due to the softening effect on crumb.