Keep Fruit and Vegetables cool. Enzyme in food begin to degrade vitamins once  picked.

Refrigerate foods in moisture proof containers. Nutrients keep best at temperature near freezing high humidity and away from exposure to air.

Avoid trimming and cutting fruits and vegetables into small pieces greater surface exposure  speeds vitamin breakdown by oxygen.

Outer leaf of  lettuce and other green vegetables have higher levels of vitamins and minerals than inner tender leaves. outer skin of potatoes, carrots, apples have higher level of macronutriments than do inner.

Steam with very little amount of water.

Do not reheat.

Do not add baking soda

Store canned food in a cool place.

Do not expose milk to sunlight.