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

Genomic dna libraries , A genomic DNA library is made from the genomic DNA ...

A genomic DNA library is made from the genomic DNA of an organism. For instance, a mouse genomic library could be made by digesting mouse nuclear DNA with a restriction nuclease to

Explain class adverse effects of nnrti, Class adverse effects of NNRTI ...

Class adverse effects of NNRTI All NNRTIs can cause a rash that is sometimes severe. NNRTIs are metabolized by and can affect hepatic CYP 450 isozymes; drug interactions can o

What is megalobastic anemia, Question 1) What is megalobastic anemia? Disc...

Question 1) What is megalobastic anemia? Discuss briefly its lab diagnosis. How would you differentiate megaloblastic anemia from other anemias? Question 2) What is hem

Define the guidelines for calculating ideal body weight, Define the Guideli...

Define the Guidelines for Calculating Ideal Body Weight? What is the ideal body weight for me? Am I obese? Am I underweight? These are the questions that must have come to your

Determine the term - akinetic and myoclonic seizures, Determine the term - ...

Determine the term - Akinetic and Myoclonic Seizures Akinetic seizures are ordinarily seen only in children. Usually, an affected child collapses suddenly and without warning.

What is the phase of the menstrual cycle, In general what is the phase of t...

In general what is the phase of the menstrual cycle when copulation may lead to fecundation? Although this is not a rule, to be effective fecundation in general must happen wit

Explain the gall bladder disease - effect of obesity, Explain the Gall blad...

Explain the Gall bladder disease - Effect of Obesity? Obesity is one of the risk factors for formation of gallstones. The super saturation of bile with cholesterol in obese ind

Deficiency diseases-phosphorus deficiency, Phosphorus deficiency Defici...

Phosphorus deficiency Deficiency of phosphorus is usually primary and is widespread under natural conditions. It is characterized by pica, poor growth, infertility, and osteody

Which is the normal sign of the electric charge, Which is the normal sign o...

Which is the normal sign of the electric charge among the two sides of the neuron plasma membrane? What is the potential difference (voltage) generated among these two sides? What

Flow cytometry, The following histograms were produced using flow cytometry...

The following histograms were produced using flow cytometry after labelling B-cell lymphocytes with propidium iodide. Histogram A is from a healthy individual while Histogram B is

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