What is the standard value of water activity in food?
Answer Posted / sulfath
The water activity scale extends from 0 (bone dry) to 1.0 (pure water) but most foods have a water activity level in the range of 0.2 for very dry foods to 0.99 for moist fresh foods. Water activity is in practice usually measured as equilibrium relative humidity (ERH).
The water activity (aw) represents the ratio of the water vapor pressure of the food to the water vapor pressure of pure water under the same conditions and it is expressed as a fraction. If we multiply this ratio by 100, we obtain the equilibrium relative humidity (ERH) that the foodstuff would produce if enclosed with air in a sealed container at constant temperature. Thus a food with a water activity (aw) of 0.7 would produce an ERH of 70%.
Fresh meat and fish
.99(a/w)
Bread
.95
Aged Cheddar
.85
Jams and jellies
.8
Plum pudding
.8
Dried Fruit
.6
Biscuits
.3
Milk powder
.2
Instant coffee
.2
Is This Answer Correct ? | 1 Yes | 0 No |
Post New Answer View All Answers
What si the self antigen for scleroderma?
Explain the biological neuron model. How is it different from artificial neuron?
What is the treatment of hiv?
What are pathogens?
What are immunoglobulins? Explain its structure.
What are the drawbacks of prosthetic limb?
Explain forbidden clones.
What are the results of hiv?
What is bispecific antibody?
Explain microarrays. How are they related to dna?
What is the lifespan of rccs?
what do you mean by non-smart instruments ? define ? give an example?
Differentiate between introns and exons.
What is retrovirus?
Explain blood brain barrier?