Ph.D. Dissertation:

Evaluation of properties of produced oleogel through foam-templated approach using white egg protein and xantan complex and its application in reduced fat muffin cake

In this study, oleogels were prepared using egg white proteins and xanthan-egg protein gum using their aerogels as a model. The combination of EWP - XG produced oleogels with OBC, different tissue properties and microstructures. XG improved the stability of EWP aerogels during freezing and immersion in oil. EWP-XG aerogels resulted in a highly porous matrix and a stable structure with high mechanical strength.The maximum amount of adsorbed oil was obtained for samples containing 1%, 0.5% and 0.75% xanthan, respectively. The results of tissue analysis showed that with increasing the amount of xanthan, the hardness of the system increases significantly. Also, according to this study, xanthan at low concentrations (0.5%) can be used to prepare EWP oleogels with higher OBC, more elastic and stable structure. According to the results of volume and density test, 10% xanthan cake treatment showed the maximum volume of 35.9 (mL) and the highest density (0.3662 g / cm).. In the test of moisture and water activity, the lowest amount of moisture with 22 ? 23 and the lowest amount of water activity among the samples containing xanthan were related to the treatment containing 10% with 0.76 water activity. The results of the hardness test showed that with increasing the amount of gum, the hardness, cohesion and chewability of the cake decreases and the adhesion increases.. In the porosity test, the lowest porosity is related to the treatment containing 10% xanthan, which is due to the non-uniformity in the distribution of air bubbles in the cake texture. The color test showed that the 10% and 30% xanthan samples had less color than the sample containing 50% xanthan, indicating a lower Millard reaction than that sample. The results of sensory evaluation by examining factors such as crust color, aroma, taste, texture, hollowness and porosity of bread crumbs, and chewability showed that the general acceptance of samples containing oleogels with 10% xanthanum, had the highest acceptance by the consumer.

Keywords: egg white protein-xanthan- carob gum- oleogel