Yogurt Production This page describes the production of yogurt and includes the legal Yogurt Definitions, Ingredients, Bacterial Cultures, and General Manufacturing Procedure. Standards of Identity listed in the U.S. Code of Federal Regulations (CFR), in sections 21 CFR 131.200, 21 CFR 131.203, and 21 CFR 131.206, respectively. The two styles of yogurt commonly found in the grocery store are set type yogurt and swiss style yogurt. Set type yogurt is when the yogurt is packaged with the fruit on the bottom of the cup and the yogurt on top. Swiss style yogurt is when the fruit is blended into the yogurt prior to packaging. Probiotic cultures benefit human health by improving lactose digestion, gastrointestinal function, and stimulating the immune system. Staff (1998), Tamime and Robinson (1999), Walstra et al. (1999) and the website by Goff, www.foodsci.uoguelph.ca/dairyedu/yogurt.html. [paste:font size="4"]General Yogurt Processing Steps Adjust Milk Composition & Blend Ingredients Pasteurize Milk Homogenize Cool Milk Inoculate with Starter Cultures Hold Cool Add Flavors & Fruit Package proteins. This allows the proteins to form a more stable gel, which prevents separation of the water during storage. The high heat treatment also further reduces the number of spoilage organisms in the milk to provide a better environment for the starter cultures to grow. Yogurt is pasteurized before the starter cultures are added to ensure that the cultures remain active in the yogurt after fermentation to act as probiotics; if the yogurt is pasteurized after fermentation the cultures will be inactivated. Starter cultures are mixed into the cooled milk. 6. Hold The milk is held at 108°F (42°C) until a pH 4.5 is reached. This allows the fermentation to progress to form a soft gel and the characteristic flavor of yogurt. This process can take several hours. 7. Cool The yogurt is cooled to 7°C to stop the fermentation process. 8. Add Fruit & Flavors Fruit and flavors are added at different steps depending on the type of yogurt. For set style yogurt the fruit is added in the bottom of the cup and then the inoculated yogurt is poured on top and the yogurt is fermented in the cup. For swiss style yogurt the fruit is blended with the fermented, cooled yogurt prior to packaging. 9. Package The yogurt is pumped from the fermentation vat and packaged as desired.