Question

. Take 400ml milk, curd, four small clean jars with lids labelled A, B, C and D. Pour about 100 ml of lukewarm boiled milk into each jar. Add a teaspoon of curd to jar A and D. Place jar D in a refrigerator. Place jars A, B and C in a warm place. Observe the jars after four to five hours and answer these questions.
i) What do you see in jars A, B and C?
ii) Why did the milk in jars B and C not set into curd?
iii) What happened in D? Can you say why?

Answer 1

1. The milk will be turned into curd in bowl A due to the lactobacillus bacteria and not in other bowls B, C.

What is lactobacillus bacteria?

Lactobacillus is the bacteria required for the formation of curd and it requires an appropriate temperature for its growth. Lukewarm milk not being very much cool and hot provides that appropriate temperature and hence lukewarm milk get converted into milk.

2. Bowl B and C contains hot and cold milk that do not provide required temperature for the growth of bacteria due to which bacteria does not grow in them and they are not converted into curd.

3. Bowl D placed in refrigerator, so the the bacteria unable to divide because they does not get the required temperature and doesn't changed into curd.

For more information regarding curd formation, visit:

https://brainly.com/question/1336120

#SPJ1