Yogurt Flashcards
What bacteria are used to make yogurt?
Lactobacillus bulgaricus and Streptococcus thermophilus.
What is the role of bacteria in yogurt production?
Ferment lactose in milk.
What does acetaldehyde contribute to in yogurt?
Characteristic flavor.
What temperature range is suitable for the fermentation process in yogurt production?
40-43℃.
How long is the culture incubated during yogurt fermentation?
4-6 hours.
What happens to the yogurt when the level of acid reaches 0.8-1.8% during fermentation?
Bacteria growth stops, but bacteria remain alive.
At what temperature should yogurt be stored to maintain bacteria viability?
4.5℃.
What causes yogurt to become unpalatable and separate after about 10 days of storage?
Bacteria increasing acid content.
What is the cause of a yogurt lid ‘blowing’?
Yeast cells fermenting sucrose to produce CO2 gas and alcohol.
What are the main bacteria in a yogurt starter culture?
Lactobacillus bulgaricus and Streptococcus thermophilus.
What is the purpose of homogenizing milk in yogurt production?
Gives yogurt a smooth, creamy texture and prevents separation.
At what temperature is milk pasteurized in yogurt production?
85-95℃.
What is the effect of cooling yogurt to 4.5℃ after fermentation?
Holds during storage and distribution.
What are some common additives in commercial yogurt?
Vitamin A and D, stabilizers, sucrose, color, preservatives, flavorings.
What ingredients are used to make yogurt in a vacuum flask at home?
Sterilized or UHT milk, dried skimmed milk, natural yogurt.
How long should yogurt be left to incubate in a vacuum flask at home?
7 hours.
What is recommended to be done with yogurt made at home within 5 days?
Use within 5 days and store in the refrigerator.
What are some yogurt products other than plain yogurt?
Bio-yogurts, yogurt drinks, yogurt ice creams, soya yogurt.
What nutrients are typically found in yogurt?
Water, protein, fat, minerals, lactose, other sugars.
What is the nutrient content difference between fruit-flavored and plain low-fat yogurt?
Variances in water, protein, fat, minerals, lactose, other sugars.
What is the purpose of artificial sweeteners in very-low fat or diet yogurts?
To reduce energy value.
What is an alternative use of yogurt in cooking instead of double cream?
Cheesecakes, cold souffles, mousses.
How can yogurt be used as a substitute in food preparation?
Salad dressings, cold drinks with fruit, certain meat dishes.
What is the importance of yogurt in the diet?
Source of nutrients, suitable for various dietary needs.
What is the role of gelatine in some yogurt products?
Improves texture and makes yogurt thick and creamy.
What is the purpose of stabilizers in commercial yogurt?
Prevent the yogurt from separating into curds and whey.
How does yogurt help in convalescence according to the document?
It is useful for convalescents.
What is the primary purpose of yogurt in energy-reduced diets?
Serving as an alternative to high-calorie desserts.
What is the shelf-life of yogurt made at home?
5 days.
What is the role of vitamin A and D in commercial yogurt production?
Added for nutritional value.
