Presentation on theme: "Yogurt And Other Products. Yogurt Semi-solid fermented milk product which originated centuries ago in Bulgaria Consistency, flavor and aroma may vary."— Presentation transcript:
Yogurt Semi-solid fermented milk product which originated centuries ago in Bulgaria Consistency, flavor and aroma may vary from one region to another
Ingredients in Yogurt Dairy Products: Whole milk, partially skimmed milk, skim milk or cream Sweeteners: glucose or sucrose, high- intensity sweeteners (e.g. aspartame) Stabilizers: gelatin, cellulose, locust bean gum, guar gum, alginates, carrageenans, whey protein concentrate Flavors: fruit preparations including natural and artificial flavoring, color
Starter Culture Microorganisms used in the production of cultured dairy products such as yogurt and cheese. Streptococcus salivarius thermophilus (ST) and Lactobacillus delbrueckii bulgaricus (LB) are used in yogurt.
These microorganisms are ultimately responsible for the formation of typical yogurt flavor and texture. The yogurt mixture coagulates during fermentation due to the drop in pH Streptococci are responsible for the initial pH drop of the yogurt mix to approximately 5.0 Lactobacilli are responsible for a further decrease to pH 4.0
Fermentation Conversion of a carbohydrate such as sugar into an acid or an alcohol Can refer to the use of yeast to change sugar into alcohol or the use of bacteria to create lactic acid in certain foods.
Chemical products made through fermentation Lactic acid: in food products usually serves as either as a pH regulator or as a preservative Acetaldehyde: makes acetic acid Acetic acid: organic acid that adds taste/flavor
Manufacturing methods Equal amounts of St to Lb inoculation is added to the jacketed fermentation tank Temperature of 110° F is maintained for 4-6 hours with no agitation pH is carefully monitored until it is 4.0 to 4.1 At this time the jacket is replaced with cool water and agitation begins, both of which stop the fermentation
Coagulated product is cooled to 45° F, depending on the product Fruit and flavor may be added at this time, then packaged Product is now cooled and stored at refrigeration temperatures (41° F) to slow down physical, chemical and microbiological degradation
Yogurt Products Stirred style yogurt Set style yogurt Fruit-on-the-bottom style: fruit mixture is layered at the bottom followed by inoculated yogurt, incubation occurs in the sealed cups Soft-serve and hard pack frozen yogurt
Greek style Blend of cream and milk, with a higher percentage of butterfat -from 4% to 10%, compared to regular whole milk yogurts that generally don’t exceed 3.5% butter fat Greek yogurt is also strained which removes more water from the yogurt, making it more dense, firm and creamy Greek style yogurt has more calories and more fat than regular yogurt; however, it also has more protein 12 grams per 8 oz serving
Buttermilk Liquid left over after producing butter from cream by the churning process Has a slightly sour taste, which is usually pleasant once people are accustomed to it
Cultured Buttermilk Most modern, commercially- available, "buttermilk" is not genuine buttermilk but rather cultured buttermilk, milk to which souring agents (Streptococci bacteria) have been added to simulate the original product
Sour Cream Cultured cream usually has a fat content between 12-30%, depending on the required properties Starter is similar to that used for cultured buttermilk Cream after standardization is usually heated to 167-176°F and is homogenized to improve the texture Inoculation and fermentation conditions are also similar to those for cultured buttermilk, but the fermentation is stopped at a pH of 4.5