Ph.D. Dissertation:

Effect of diffrent starches formulation and ultrasound pretreatments on batters functionality of chicken nuggets

This study was tested to evaluate the influences of different maize starches (native, modified with sonication, pre –gelenized, Heat Resistant) replacement in batter coating, based on factorial experiments in a completely randomized design to determine the optimal formulation of breadcrumbs.Samples were sonicated with 70 kHz for 5 minutes and a fryer equipped with a temperature controller (150, 190 and 170 degrees Centigrad) and time (1, 3 and 5 minutes) was used for frying. Physico-chemical changes of corn starch (water absorption, solubility, granular microscopic properties), physical properties of the batter (consistency, pich -up, rheological properties) andquality parameters (pick up, color, oil absorption, moisture content, cooking yield, sensory properties and texture) of chicken nugget were mesured during frying.Batters with no maize starch addition was used as control batter formulation. Obtained result indicated that the rate of starch water solubility and water absorption were increased between 4 to 9.86 and 5.72 to 9.42% respectively. Water solubility and water absorption of the samples increased due to sonication pretreatment. Starch intermolecular interfaces were broken down by sonication diffusion Anova showed that batter formulation (frying time and tempreture) had significant influence (p<0.05) on the moisture content. The oil content of whole nuggets was found to decrease with frying time. Chicken nuggets with native maize starch and control ones differed significantly (P< 0.05) for coating pickup. Color evaluation in samples containing native and sonication pretreatment showed significant (P< 0.05) reduction in a* and b* values at 3 minute frying, whereas L* values were significantly (P< 0.05) increased compared to control treatments at 170 and 190° c. Hardness of chicken nuggets significantly (P< 0.05) decreased especially samples containing sonication pretreatment of maize starches gained the highest score in softness and tenderness at 190° c. Additionally batters illustrated shear tinning behavior. Apparent viscosity had positive impact on coating pick up. Experimental values of consistency coefficient k, varied from 6.150–11.468 Pa.sn and flow behavior index n from 0.412 to 0.602. Sonication pretreatment samples resulted in higher overall acceptability scores and a compared to other samples. The highest amount of porosity was seen in sonication pretreatment samples at 190°C and nuggets containing native starch had the lowest amount. .

Keywords: Sonication, Chicken nugget, Batter, Starch