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

Define the single cell proteins (scp), Define the Single Cell Proteins (SCP...

Define the Single Cell Proteins (SCP)? You may have heard of SCP. What is a single cell protein? Let's find out. The term SCP was coined by Prof. Caroll Wilson (MIT) in 1966. I

gas exchange, what are the organs of respiration in the lower form of anim...

what are the organs of respiration in the lower form of animals?

Synthesis and storage of hormone, Synthesis and Storage of Hormone The...

Synthesis and Storage of Hormone The synthesis and storage of hormone depends on the nature of the hormone. Steroid hormones are secreted in diffuse molecular form and usually

Define the standard deviation (2 score) classification, Define the Standard...

Define the Standard Deviation (2 score) classification? Statistics teaches us that when normal values of any variable are distributed as per their frequency of occurrence, they

Calculate micronutrient and other nutrient requirements, Calculate Micronut...

Calculate Micronutrient and other specific nutrient requirements? The recommended average daily per capita intake of various specific nutrients for typical population requiring

Benefits of cross-pollination, Benefits of Cross-Pollination Because o...

Benefits of Cross-Pollination Because of the specific benefits of cross-pollination, flowering plants have evolved many devices to prevent self-pollination and to encourage cr

Denitrification - nutrient cycles, Denitrification - Nutrient Cycles N...

Denitrification - Nutrient Cycles Nitrates are readily leached from the soil and also lost through denitrification the process by which molecular or gaseous nitrogen (N 2 ) as

Chemolithoautotrophs - nutritional types of microorganisms, Explain Chemoli...

Explain Chemolithoautotrophs - Nutritional Types of Microorganisms These microorganisms use inorganic compound as source of energy and electron and CO 2 as a source of carbon.

Meiosis, MEIOSIS Every  organism is mortal, It  becomes  old and wornou...

MEIOSIS Every  organism is mortal, It  becomes  old and wornout  with advancing age  (= ageing )  and ultimately dies ,Before  death   however  ,it reproduces its own  kind, so

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

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