Preserving foods, Biology

Assignment Help:

One of man's oldest methods of preserving foods is drying or desiccation. The preservation of foods by drying is a direct result of removal of moisture. Microorganisms need water for growth. The exact amount of water needed for growth of microorganisms varies. This water requirement of microorganisms is best expressed in terms of available water or water activity aw, the vapour pressure of the solution (of solutes in water in most foods) divided by the vapour pressure of the solvent (usually water). Thus aw, for pure water would be 1.00. The water activity depends on the number of molecules and ions present in solution, rather than their size. Thus a compound like sodium chloride, which dissociates into two ions in solution, is more effective at reducing the water activity than a compound like sucrose on mole-to-mole basis.


Related Discussions:- Preserving foods

Soils of tropical and temperate forests, Soils of Tropical and Temperate Fo...

Soils of Tropical and Temperate Forests Although soils of tropical forests are generally poor in nutrients they are able to maintain high productivity under natural conditions

Explain the active transport process, Which of the following is an active t...

Which of the following is an active transport process? A. Net flux of sodium across the plasma membrane via voltage-gated sodium channels. B. Net flux of glucose across the

What is mutualism, What is mutualism? Mutualism is the ecological inte...

What is mutualism? Mutualism is the ecological interaction in which both participants advantage and that is obligatory for their survival. Mutualism is a harmonious (positive)

Explain the process of nuclear reorganization, Process of nuclear reorganiz...

Process of nuclear reorganization in protozoa in which nucleus divides, each half undergoes a maturation, and two persisting functional nuclei reunite is termed as: a) Autogamy

Difference between cerebrum and brain, Q. What is the difference between ce...

Q. What is the difference between cerebrum and brain? What are the major parts of these structures? The concept of brain or encephalon comprehends the cerebrum mostly referred

What factor contributed to the current variations, According to the theory ...

According to the theory of natural selection, what factor below contributed to the current variations in beak sizes of finch species on the Galapagos Islands? a. Finches dispersed

Cell, How cell divides?

How cell divides?

What is transportation of sick newborn infants-heart disease, What is Trans...

What is Transportation of Sick Newborn Infants with Heart Disease Communication : The decision to transport a newborn to a tertiay referral centre with facilities for specia

Coordination and response, Name the two hormones produced by the pancreas a...

Name the two hormones produced by the pancreas ans say in what circumstances, in what way, they adjust the glucose concentration in the blood.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd