This set of Food Microbiology Multiple Choice Questions & Answers (MCQs) focuses on “Fermented Dairy Products – Buttermilk”.
1. ______________ buttermilk is produced in the same way as acidophilus milk.
a) Czech
b) Hungarian
c) German
d) Bulgarian
View Answer
Explanation: Bulgarian buttermilk is made using Lactobacillus bulgaricus instead of L. acidophilus. The acidophilus bacteria have the ability to colonize the gut unlike L. bulgaricus.
2. Buttermilk is added to __________ to leaven bread.
a) Milk
b) Baking Soda
c) Flour
d) Egg
View Answer
Explanation: Buttermilk is acidic due to the presence of lactic acid. When this is added to baking soda, the reaction produces gas. This leavens the bread, thus making it softer.
3. Too much acetaldehyde production should be avoided during the production of buttermilk.
a) True
b) False
View Answer
Explanation: An excess of acetaldehyde might cause defects in buttermilk. These defects include undesired green or yogurt flavor defects.
4. Which of the following is added to milk for better flavored buttermilk?
a) Glucose
b) Sodium acetate
c) Acetic acid
d) Sodium citrate
View Answer
Explanation: Citrate is present in fresh milk but the level reduces during storage. Hence, sodium citrate is added to milk during the production of cultured buttermilk.
5. The ratio of __________:____________ should be > 3:1 and < 4.5:1 for a desirable quality.
a) Acetaldehyde:Diacetyl
b) Lactose:Lactic acid
c) Diacetyl:Acetaldehyde
d) Lactic acid:Lactose
View Answer
Explanation: Buttermilk gets its aroma from diacetyl and flavor from acetaldehyde. These two components have to be in the perfect ratio for desirable quality buttermilk. An excess of acetaldehyde can lead to yogurt flavor defects.
6. For the growth of species, fermentation is carried out at 295.37 K.
a) True
b) False
View Answer
Explanation: The above temperature is the optimum temperature for the balanced growth of both, Leuconostoc and Lactococcus. The acidic and flavor components are perfect when the growth is balanced. When the temperature is above 295.37 K, it facilitates the growth of Lactococcus more than Leuconostoc and this leads to more acid production and less flavor. When the temperature is below 295.37 K, it is vice versa and it leads to more flavor and less acid.
Sanfoundry Global Education & Learning Series – Food Microbiology.
To practice all areas of Food Microbiology, here is complete set of Multiple Choice Questions and Answers.