food preservation teaching outline - Oregon State University ...

Mold—caused by food not dried enough or not stored properly so that moisture was
re-absorbed by food.
Sugar crystals—often happens with overripe fruit. Safe to eat. Will dissolve if
cooked.
Insect infestation.
L. Rehydration and using dried foods
Fruits
- Can be eaten as is—no rehydration needed.
- Can be rehydrated by:
1. Pouring boiling water or juice on fruit. Let stand 5-10 minutes.
2. Steam fruit over boiling water 3-5 minutes.
3. Soak in cold water for several hours.
4. Cover with water and bring to boil in microwave. Let stand 5-10 minutes.
5. Soaking fruit first in cold water, then cooking gives a more tender product.
- Chopping fruits
1. Freeze fruit first then crush with hammer or meat cleaver.
2. Put frozen fruit in blender or food processor.
3. Cut pieces of fruit with scissors or sharp knife. If fruit tends to stick coat
blade with a little cooking oil.
Vegetables
- Dried vegetables will be tenderer if soaked before cooking. Can take 15 minutes
to 2 hours to plump. Then cook or add to soup or stew.
- Take longer to rehydrate than fruit because more water is lost.
- Do not let soaking vegetables stand longer than 2 hours without refrigeration.
- Vegetable flakes and powders.
- Can use blender or food processor to flake or make vegetable powders – great
seasonings.
Food spoilage
- Rehydrated dried foods should be refrigerated. Very susceptible to spoilage.
Fruit and Vegetable Leather
A. What is it?
B. Leathers are a chewy product usually made from pureed fruits but some vegetables like
tomatoes also make good leather.
C. What fruits to use
Fresh fruits
- Any fresh fruit will work—good place to use culls, overripe fruit or those not
suitable for canning or freezing.
- Cut away all bruises and spoiled portions.
- Citrus fruits should be used in combination with other fruits because they are so
juicy.
- Fresh fruit purees are usually too thin to use as is-need to be cooked to thicken
or blend with drained canned fruit such as pears or apple sauce.
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