rechnological Studies on Frozen Yoghurt

Abstract

Frozen yoghurt is a frozen dairy product in which yoghurt is a major component. It is relatively new product that can expand the market for• ice cream makers. Aiming to improve the quality of frozen yoghurt, this study was carried out in two parts , - In the first one the standardized milk in the mix was replaced by different levels of yoghurt. - In the second part the standardized milk used in the mix was fermented to different values of pH before mix preparation. Some properties and quality of the mixes and resultant frozen yoghurt were followed. The results could be summarized in the following: - Specific gravity and weight per gallon of the mixes were not • affected by the yoghurt level in the mix or by the pH of added cultured milk, but slightly increased as fruit solids was increased in the mix. - The mix acidity increased and the pH decreased by increasing the yoghurt level or using low pH culture milk or by adding fruits to the mix. - As the yoghurt level increased in the mix or the pH of added cultured milk decreased or fruits were added. The corresponding values ofviscosity was increased. - Freezing point of the mixes :Y.f!S not afi'ected by the yoghurt level in the mix or by the pH of added cultured milk, but adding fruits decreased the freezing point. - The overrun of frozen yoghurt was decreased by increasing the yoghurt level in the mix or decreasing the pH of added cultured milk or by adding fruits. An opposite trend was recorded for specific gravity and weight per gallon of the frozen yoghurt. - The low melting rate of frozen yoghurt was related to the high level of yoghurt and low pH of added cultured milk to the mix.