Chemical aspects of food technology Flashcards
What is often the first step in the processing of a plant-based raw material?
‘breking’ the plant tissue by cutting, grating, grinding and so forth. Leading to the release of various chemical compounds/enzymes.
In which two groups can food components be divided in?
the major- and minor food components. Major: present in food in large amounts. Minor: present in food in small amounts.
What are raw materials?
unprocessed foods as such, derived from the land or directly from animals.
What are processed foods?
Food products made from processed raw materials.
What are ingredients?
Processed foods from one single raw material.
What are complex food products?
Food products made from several ingredients and raw materials.
What are taste and aroma dependent on?
taste is determined by the sugar/acid ratio.
aroma is dependent on the volatile aroma compounds.
What do antioxidants do?
They delay or prevent oxidation reactions.
What are typical oxidation results?
- loss of quality of food
- loss of color
- loss of vitamins
Name two types of antioxidants.
antioxidants that scavenge free radicals and antioxidants that reverse oxidation reactions.
What is a phenolic compound?
a benzene ring with a hydroxyl-group attached to the ring, which acts as a antioxidant by reacting with the free radical HO*.
How can a radical be ‘trapped’ inside a phenolic compound?
Because of the resonance that takes place in the benzene ring and O atom.
What is °Brix equal to?
To the mass percentage dissolved dry matter in the liquid.
What is the pKa?
The pH value where there are equal molar concentrations of the non-dissociated and the dissociated acid present.
How can the sugar/acid ratio bee calculated?
By dividing the °Brit by the acidity.
