Question

how does the addition of salt or sugar improve the shelf life of some food items​

Answer 1

Answer:

Salt keeps many insects and micro organisms away from the food we shelve-store but sugar may invite ants to finish up the food.

Answer 2

Answer: microorganism cannot grow in high concentration of sugar or salt. Fruit squash, jam ,jellies are preserved by adding sugar.Salt is added in the pickles to preserve for longer time.Fish can be preserved for few months if immersed in the concentrated solution of salt. Meat and fish are covered with dry salt to check the growth of bacteria. Sugar reduces the moisture content which inhibits the growth of bacteria which spoils food.

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