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

Explain about the sucralose - artificial sweeteners, Explain about the Sucr...

Explain about the Sucralose - artificial sweeteners? Sucralose (1, 6-dichloro-1, 6-dideoxy-β-D-fructofuranosyl-4-chloro-4-deoxy-α-D- galactopyranoside) is the only non-nutritiv

Protozoans - regeneration in invertebrates, Protozoans - Regeneration i...

Protozoans - Regeneration in Invertebrates Most single celled animals such as protists, i.e. protozoans, regenerate very well. If part of the cytoplasm is removed from the

Methods to overcome incompatibility, Methods to Overcome Incompatibility ...

Methods to Overcome Incompatibility It has been possible to facilitate the germination of incompatible pollen by extracting pollen wall proteins from compatible pollen and su

Extraembryonic membranes the same in all vertebrates, Are the extraembryoni...

Are the extraembryonic membranes the same in all vertebrates? The presence of each extraembryonic membrane varies according to the vertebrate class. In fishes and amphibians

Embryology, what is the full name of Balfour in Balour''s law of cleavage?

what is the full name of Balfour in Balour''s law of cleavage?

Theory of embryology - organizer theory, ORGANIZER THEORY - It was p...

ORGANIZER THEORY - It was propounded by spemann (1901). He was given Nobel prize of 1935 for this wrok. He studied the embryonic development of frog, newt & other amph

Synthesis of sucrose, Many of the glyceraldehyde 3-phosphate produced by th...

Many of the glyceraldehyde 3-phosphate produced by the Calvin cycle in chloroplasts is exported to the cytosol and used to produce the disaccharide, sucrose. 1 st the   glyceralde

How do embryos of placental mammals excrete nitrogen wastes, Q. How do embr...

Q. How do embryos of placental mammals excrete nitrogen wastes? Placental animals including embryos and excrete urea, In the adult placental mammal urea is excreted through the

Rassenkreis and speciation, According to the current concept of speciation,...

According to the current concept of speciation, a widely distributed species should break up into partially isolated rule species. The different subspecies become differentiated fu

Endocrine system, INTRODUCTIO N - Endocrinolog y - Study of endocri...

INTRODUCTIO N - Endocrinolog y - Study of endocrine glands, hormones and their effects. Thomas Addison - Father of endocrinology. Described hormonal disease in 1855 kn

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