Investigation the effect of polyglycerol ester and diacetiyltartaric acid ester in the form of gel on physicochemical, rheological and sensory properties of oily cake

Application of emulsifiers is important in production of good quality cake. Monoglycoside and its derivatives, sterol lactilat, propylene glycol, Mono stearate, Mono stearate sorbitan, polysorbate, lecithin are used as Emulsifiersin in cake industry. Emulsifier that is used as a gel form in production of cakes , called cake gel. The use of gel cake in the cake batter increases distribution of air bubbles and resulting viscosity was increased and form a better texture and volume of the cake.Today, crystalline alpha gel of glycerol ester with alpha gel monoglycerides and propylene glycol stearate gel was used in the production of cakes. The stable Alpha gel wiche made from a mixture of monoglycerides and polyglycerol ester glycerol have impact effect on cake quality. The purpose of this study was to investigated the effect of Datem emulsifiers in three levels (5, 10 and 15%) poly glycerol in two levels (10 and 15%) and monoglycoside (60%) in gel emulsifier formulation to improve physicochemical, rheological and sensory properties of oil cake. The color index (L *, a * and b *), specific volume, texture and moisture of the cake were evaluated. The results showed that Datm emulsifier in (10%) with polyglycerol at 15% concentrations in gel emulsifier formulation had the best result on quality properties of cake.
Material and The materials was used in the production gel Emulsifier includs, glycerol (co-Timer Network Malaysia), sorbitol (Omid company) and Propylene glycol (Kimiya garan Emroz Chemical Industry Co.) was prepared. Materials for production of cakes containing wheat flour ( Khorasan Co.) with moisture content (14%), protein (8.5%), ash (48%), PH (6.2%), eggs (Telavang Co.), vanilla from (AROMA Company), liquid vegetable oil (Laden Company) invert syrup (Simorgh Co) were prepared. baking powder (Mahsa) was purchased from local market. Sugar with fine white crystals bought in batches of 15 kg and was kept in the Store for consumption.Ingredients of gel Emulsifier formulation were mixed together Continuous agitation, the mixture then heated at temperature of 70 ° C In order to prepare the cake batter, the ingredients were weighed according to the formulation. The Moisture content of cup cake was measured 2 hr and 1 week after baking according to AACC- methods (AACC, 2000). Specific volume was determined an hour after baking based on rapeseed displacement method (AACC 2000). TPA test of cup cake was measured by A QTS texture analyser (CNS Farnell, Hertfordshire, UK) to measure the force required for penetration 2h and 1 week after baking. The color of cup cake determined by L*, a* and b* index, by using image j software after 2 hr, by (HP Scanjet , G 3010). Sensory evaluation was performed by 10 trained panellists and the overall quality of cake was evaluated using a ranking scale with scores ranging from 1 (least pleasure) to 5 (best pleasure).In this study, some sensory properties including odor, taste, texture and overall quality (total acceptance) of cup cake were evaluated. Results were reported as the average of three replications (all treatments were evaluated in three batches). In order to assess significant differences among samples, a complete randomized design of triplicate analyses of samples was performed using the Mstat-c. Duncan’s new multiple range tests were used to study the statistical differences of the means with 95% confidence.
The results showed that gel emulsifier formulation with (10%) concentrations of Datm and (15%) concentration of polyglycerol are suitable in gel emulsifier formulation, This formula was increased the volume, L* index of crust and crumb of cake and sensory properties such as texture, Chewiness and reduced firmness of cake and moisture loss content over 1 week after the baking . Increasing the specific volume of cakes is due to the formation of alpha crystal films around the air bubbles, and trapping air bubbles in the dough. This phenomen was reduced surface tension of fat phase and improved spread ability of the fat phase in the cake batter, thus increasing the volume and softness of cake. Reduction of cake Firmness is due to interaction of emulsifiers with starch that is prevent retrogradation phenomenon. increasing of poly¬glycerol ester concentration in gel emulsifier formulation, improved the moisture maintain during baking and prevent from rough and wrinkled skins in the final product and therefore increases L* index .