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 whey protein concentrates, Explain Whey protein concentrates Whe...

Explain Whey protein concentrates Whey protein concentrates (WPC) are  the products derived from whey from which the water, minerals and lactose have been removed.  WPC is a wh

Investigating, What is scientific investigation?

What is scientific investigation?

Light requirement - seed dormancy, Light Requirement - Seed Dormancy T...

Light Requirement - Seed Dormancy The light requirement for germination of many seeds is presumably a mechanism that prevents the germination of small seeds buried deep underg

Oxygen dissociation curves, Oxygen Dissociation Curves The oxygen cont...

Oxygen Dissociation Curves The oxygen content of blood fully saturated or oxygenated can be calculated. It is known as the oxygen capacity of blood and this varies for differe

Define precautions for preparation of phosphate buffers, Define Precautions...

Define Precautions for Preparation of Phosphate Buffers? 1. Glass electrodes should always be dried before and after measuring pH with a tissue paper. 2. The pipettes should

How do bacteria reproduce, How do bacteria reproduce? Bacteria replicat...

How do bacteria reproduce? Bacteria replicate by binary fission (scissiparity). Some bacteria though present a kind of sexual reproduction (transformation, transduction or conj

Chronic exposure of cadmium, Q. Chronic exposure of Cadmium? An increa...

Q. Chronic exposure of Cadmium? An increase in the soil cadmium content due to soil pollution by industrial wastes, burning of coal, fossil fuels, sewage sludge, medical and

Explain the use of bacterial vaginosis in pregnancy, Use of Bacterial vagin...

Use of Bacterial vaginosis In pregnancy  Bacterial vaginosis has been associated with premature labor and complications of delivery, and symptomatic bacterial vaginosis in preg

Its possible to obtain probability of emergence of genotype?, How is it pos...

How is it possible to obtain the probability of emergence of a given genotype formed of more than one pair of different alleles with independent segregation from the knowledge of t

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