Nutrient
a food component necessary to sustain life, which includes water, carbohydrates, fats, proteins, vitamins, and minerals
Nonpolar covalent bond
is electrically neutral because the electrons are shared equally
Polar covalent bonds
there is an unequal sharing of electrons within the molecule
Hydrogen bond
the positive hydrogen end of one water molecule is drawn toward the negative oxygen ends of other water molecules
Intermolecular
between molecules, much weaker than covalent bonds
Surface tension
the force between molecules at the outside edge of a substance
Atmospheric pressure
the force of this weight pressing down on a surface
Impurity
anything that is added to a completely pure substance
Free water
liquid easily separated from food tissues, can be pressed or squeezed from the food
Bound water
tied to the structure of large molecules
Hydrate
any chemical compound that is loosely bound with water
Anhydrous
compounds that have the water driven off when heated
Water activity
the measure of of the partial water pressure over a food
Hydrated
full of water
Contaminate/pollutant
anything that makes a substance impure or unsuitable
