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

What is the nucleolus, The nucleolus is a small and optically dense region ...

The nucleolus is a small and optically dense region in the interior of the cell nucleus. It is made of ribosomic RNA (rRNA) and proteins. Single nucleus can have one or more nucleo

St depression at rest, Q. What is ST depression at rest? As early as 19...

Q. What is ST depression at rest? As early as 1965 Ostrand called attention to the syndrome of short PR interval without accelerated conduction and it's association with ST dep

202, sizes in some biological systems glucose

sizes in some biological systems glucose

Explain the hydration properties of proteins, Hydration Properties  Gen...

Hydration Properties  General conformation of individual proteins in solution is largely dependent on the interaction with water.  The progressive hydration of proteins startin

Symptoms and signs of diabetes mellitus, Symptoms refer to the problems exp...

Symptoms refer to the problems expressed by the patients. Signs are obtained by a health professional from the patients by interacting with him, by conducting tests, etc. The sympt

Parts of a typical flower with all its definations , parts of a typical fl...

parts of a typical flower? define its parts and internal parts completely? show complete colourful diagram?

Inrinsic conduction system of the heart, The cardiovascular system controls...

The cardiovascular system controls the movement of blood through thousands of miles of capillaries so that every tissue  in every part of the body is perfused. Essential nutrients

Define nutritional support management for pancreatic cancer, Define Nutriti...

Define Nutritional Support Management for pancreatic cancer? When there is deficiency of exocrine pancreatic secretions, adequate amounts of pancreatic extract are helpful. It

Growth rate in animals, GROWTH RATE IN ANIMALS - Growth rate is differe...

GROWTH RATE IN ANIMALS - Growth rate is different at different periods of life. Growth period in human may be studied in 5 steps - (i) Prenatal - In gestation period fo

Explain how will you perform ward radiography?, Question 1 Explain how ...

Question 1 Explain how will you perform ward radiography? Question 2 Discuss the radiographic projections recommended for imaging the first to third cervical vertebr

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