Question

Sour cream is produced by
A. Leuconostoc cremoris
B. Streptococcus lactis
C. Lactobacillus acidophilus
D. Both A and B

Answer 1

Hint: Sour cream or soured cream is a dairy product derived by fermenting some forms of lactic acid bacteria with normal cream.

Complete Answer:
- The bacterial culture, which is either purposely or spontaneously added, sours and thickens the milk. Its name comes from the bacterial fermentation production of lactic acid, which is called souring.
- Historically, sour cream was created by letting cream at a moderate temperature that was skimmed off the top of the milk ferment. It can also be prepared by souring with the acid-producing bacterial culture of pasteurised cream.
- The bacteria that formed during fermentation thickened the cream and made it more acidic, a natural way to preserve it. Sour cream is the cream that some bacteria species prepare by fermenting the cream.
- The species of bacteria which are most widely used for sour cream preparation are Streptococcus lactis and Leuconostoc cremoris. These bacteria carry out the fermentation of lactic acid. Lactose is the fermentable sugar found in milk or cream. The lactose sugar is fermented to produce the bitter taste of lactic acid.
- Taste: Creamy, dense, and tangy
- Varieties: Light, normal (light or reduced-fat), fat-free, milk-free, fat-free.
- Shelf Life: Cooled three weeks after the date of sale
- Substitutes: Yoghurt, cottage cheese, buttermilk, cream cheese, evaporated milk

The correct Answer is option (D) Both A and B.

Note: Sour cream is identical to creme fraiche, a French ingredient. Both are white dairy products that thicken the cream and give it a tangy taste, made with bacteria. The key difference is that there is more fat in creme fraiche, making it ideal for high-heat cooking that would cause sour cream to curdle. In comparison, sour cream appears to be more tart, and it can be either very smooth or somewhat runny with creme fraiche.