Thesis:

Study of the effect of adding orange peel powder on the physical, chemical and sensory of low-fat mixed yogurt

Abstract:Yogurt is one of the most important fermented milk products. Due to the increase in public awareness of the health benefits of our yogurt in recent decades, its production and consumption has increased significantly. Yogurt is a good option for producing useful products due to its high nutritional value. Orange peel powder is a good source of protein, carbohydrates, unsaturated fatty acids, minerals, vitamins, fiber and a significant amount of other biologically active components such as polyphenols, antioxidants and more. The presence of these nutrients and potential functional properties has led to the use of this grain in the production of beneficial foods. In this study, first ground orange peel was added to yogurt milk at four levels (3, 5, 7 and 10%) and pasteurized after adjusting the dry matter and fat. After pasteurization, when the milk temperature reached 45 degrees Celsius, inoculation with lactic acid bacteria (Streptococcus thermophilus and Lactobacillus bulgaricus) was performed and incubation was performed. After reaching a pH of 4.6, the yogurt was removed from the greenhouse and stored in the refrigerator at 4 ° C. Each week, a sample of each treatment was selected and chemical experiments (pH, acidity, dry matter, hydration, etc.) and sensory tests were performed. Enrichment of yogurt with different percentages of orange peel powder significantly reduced the rate of hydration, pH and increased acidity, dry matter and viscosity (p <0.05). The sensory test of the enriched samples showed that there was no significant difference except for the texture between the enriched and control samples (p <0.05). The results of this study showed that the use of orange peel powder in agitated yogurt has led to the production of a product with desirable and acceptable characteristics for consumers.

Keywords: orange peel powder, yogurt, Sensory, Physicochemical characteristics