M.A. Thesis:

Cheese pizza enriched with plant oils and extracts of carrot

Pizza cheeses belong to the family of Pastafylata. Low-moisture Mozarella cheese has also been called pizza cheese. Dairy products are commonly known as healthy food. However, because of adding polyunsaturated fatty acids during the saturation process, it has been turned into a controversial issue in recent years. In this study, fortified pizza cheese based on soybean oil and extracts of carrot has been produced. To this end, according to central composite design, the effect of adding different surfaces of soybean oil (5-20 percent) and extracts of carrot (5-20 percent) have been investigated on the microbial test, texture profile analysis (TPA), stretch test, melt test, colorimetric, sensory analysis and physicochemical properties of fortified pizza cheese during the time 21 days in5 degree centigrade. Statistical analysis has been done with Design-Expert. The result of chemical experiments indicated that the amount of fat, moisture, protein, acidity, ash, pH, peroxide index and acid velue were affected by the above-mentioned factors. Soybean oil and extracts of carrot significantly affected the meltability and traction features of fortified pizza cheese in a way that the increase in extracts of carrot resulted in an increase in meltability. The highest level of meltability (74/20) were found in the 5 percent soyabean oil sample and the 12/5 percent extracts of carrot sample. Also, the highest amount of stretch was obtained with the highest amount of extracts of carrot and lowest amount of soybean oil (312/513mm). The hardness, elasticity and Gumminess decreased significantly as the amount of soybean oil and extracts of carrot increased. On the other hand, the gum-like feature was the only characteristic that increased along with the increase in both factors. The result of microbial tests indicated that microbial contaminations were not the result of soybean oil and extracts of carrot. The result of colormetrical indicated that the increase in soybean oil and extracts of carrot decrease light feature, but yellow and red features increase as the amount of soybean oil and extracts of carrot increase. The result of sensory tests indicated that the sample containing 20 percent soybean oil and 12/5 percent extracts of carrot obtained the highest score. As a result, it would be possible to produce fortified pizza cheese based on soybean oil and extracts of carrot.

Keywords: Pizza Cheese, Fortified, RSM, Shelf life