Freezing Rick Sloan FCS Agent

What will we learn?  Principles of Freezing  Freezers  Packaging Materials  Freezing Foods  Shelf-life of Frozen Foods  Emergencies 2Home Food Preservation

Principles of Freezing 3Home Food Preservation

Principles of Freezing  Does not sterilize food.  Extreme cold (0 o F or colder): stops growth of microorganisms and Slows chemical changes, such as enzymatic reactions. 4Home Food Preservation

Advantages of Freezing  Many foods can be frozen.  Natural color, flavor, and nutritive value retained.  Texture usually better than other methods of food preservation.  Foods can be frozen in less time than they can be dried or canned. 5Home Food Preservation

Advantages of Freezing  Simple procedures.  Adds convenience to food preparation.  Proportions can be adapted to needs unlike other home preservation methods.  Kitchen remains cool and comfortable. 6Home Food Preservation

Disadvantages of Freezing  Texture of some foods is undesirable because of freezing process.  Initial investment and cost of maintaining freezer is high.  Storage space limited by capacity of freezer. 7Home Food Preservation

How Freezing Affects Food Chemical changes Enzymes in vegetables Enzymes in fruit Rancidity Texture Changes Expansion of food Ice crystals 8Home Food Preservation

Freezers 9Home Food Preservation

Freezer Selection Consider: Size Shape Efficiency Defrosting features Available floor area Amount of freezer space needed 10Home Food Preservation

Freezer Selection What size? General Rule  Allow 6 cubic feet of freezer space per person (3 cubic feet per person might be adequate if other methods of food preservation are used). Standard Freezer  Capacity pounds of frozen food per cubic foot or usable space. 11Home Food Preservation

Types of Freezers Upright 6 to 22 cubic feet Convenient Uses small floor space Easy to load and unload 12Home Food Preservation

Types of Freezers Chest 6 to32 cubic feet Takes more floor space More economical to buy and to operate than upright Loses less air when opened 13Home Food Preservation

Types of Freezers Refrigerator - Freezer Combination 2 to 6 cubic feet Be sure can set temperature at 0ºF or colder Freezer can be above, below, or beside refrigerator area Other features  Self defrosting or manual defrost  Receptacle clips - prevent accidental disconnecting  Door locks and drains for defrosting 14Home Food Preservation

Location and Placement of Freezer  Place in convenient, cool, dry, well-ventilated area.  Do not place by stove, range, water heater or in the sun.  Do not push flush against wall. Leave space for air circulation and cleaning.  Be sure freezer is level. 15Home Food Preservation

Packaging Materials 16Home Food Preservation

Packaging Materials  Moisture-vapor resistant  Durable and leak-proof  Not become brittle and crack at low temperatures.  Resistant to oil, grease, or water  Protects foods from absorption of off-flavors or odors  Easy to seal and mark 17Home Food Preservation

Types of Packaging Materials  Rigid Containers Plastic freezer containers Freezer boxes with liners Coffee canisters Wide mouth canning/freezing jars  Good for liquids, soft, juicy, or liquid- packed foods  May be reusable  Hold their shape and can be stored upright 18Home Food Preservation

Types of Packaging Materials Non-Rigid Containers Bags Wrappings - cellophane, heavy-duty aluminum foil, polyethylene, laminated paper Good for firm, non-juicy foods 19Home Food Preservation

Freezing Foods 20Home Food Preservation

General Freezing Instructions Selection Freezing does not improve quality. Choose the highest quality available. Freeze promptly. Remember some foods do not freeze well. Preparation Work under sanitary conditions. Follow recommended procedures. 21Home Food Preservation

Packing Foods to be Frozen  Cool food before freezing. Ice bath  Pack in serving size quantities. Usually up to 1 quart  Pack foods tightly.  Allow for some headspace. Vegetables like broccoli and asparagus, bony pieces of meat, tray packed foods, and breads, do not need any headspace. 22Home Food Preservation

Packing Foods to be Frozen  Press all air from bagged foods, seal bags by twisting and then folding over loose edge (gooseneck). Secure with string, twist-tie or rubber band.  Use tight lid on rigid containers and keep sealing edge clean. Use freezer tape on loose fitting covers. 23Home Food Preservation

Washing Fruits and Vegetables  Wash fruits and vegetables in warm water before freezer.  The only exception to this rule is that blueberries should not be washed before freezing. 24Home Food Preservation

Labels  Name of product  Added ingredients  Form of food: halves, whole, or ground  Packing date  Number of servings or amount 25Home Food Preservation

Freezing  Freeze foods at <0ºF (set freezer at -10ºF at least 24 hours before freezing foods).  Freeze foods immediately.  Do not overload freezer with unfrozen food. Freeze amount that will freeze in 24 hours -- 2 to 3 pounds of food per cubic foot.  Pack already frozen foods together so they do not thaw. 26Home Food Preservation

Freezing  Place unfrozen foods in contact with surfaces and in coldest parts of freezer.  Leave space so air can circulate.  When food is frozen, organize freezer into types of food.  Arrange frozen foods so that the foods frozen longer can be used first.  Keep a current frozen foods inventory.  Check freezer temperature periodically. 27Home Food Preservation

Sweetened Packs for Fruit Syrup Pack Better texture Not needed for safety Fruits should be covered with syrup  Place crumpled water-resistant paper in top of container 28Home Food Preservation

Sweetened Packs for Fruit Sugar Pack Soft sliced fruits (strawberries, peaches, etc.) make on syrup when mixed with the right proportion of sugar. Layer fruit and sugar. Allow it to stand for 15 minutes. 29Home Food Preservation

Unsweetened Packs for Fruit Dry Pack Good for small whole fruits such as berries that do not need sugar. Simply pack into containers and freeze. Can freeze on a tray first, so pour easily. Pectin Syrup Good for strawberries and peaches. Mix 1 pkg. powdered pectin and 1 cup water. Bring to boil, boil 1 minute. Remove from heat, cool, and add 1-3/4 cups more water. 30Home Food Preservation

Unsweetened Packs for Fruit Water or Unsweetened Juice Packs Texture will be mushier. Color poorer. Freezes harder, takes longer to thaw. 31Home Food Preservation

Packs for Purees or Juices  Pack as is, with or without sugar.  Add ascorbic acid if light-colored. 32Home Food Preservation

Artificial Sweeteners  Can be used in the pectin syrup, juice, or water packs.  Or could be added just before serving  Do not help with color retention or texture, like sugar does.  Use amounts on product labels. 33Home Food Preservation

Preventing Fruit Darkening  The following work well: 1 teaspoon (3000 mg) ascorbic acid to one gallon of water Commercial ascorbic acid mixture Heating the fruit  The following do not work as well: Citric acid solution Lemon juice Sugar syrup Salt/vinegar solution 34Home Food Preservation

Preventing Discoloration during Freezing Ascorbic Acid Is the most economical. Use powdered or tablet form. 1/2 teaspoon powdered ascorbic acid = 1500 mg Crush tablets well. Use amount specified for each fruit. In syrup or liquid packs, add powder to liquid. 35Home Food Preservation

Preventing Discoloration during Freezing In sugar or dry packs, dissolve 2 to 3 tablespoons in cold water and sprinkle over fruit. For crushed fruit, purees or juices, mix with fruit about 1/8 teaspoon per quart.  Ascorbic Acid Mixtures Follow package directions 36Home Food Preservation

Preventing Discoloration during Freezing  Citric Acid or Lemon Juice Not as effective May mask flavors  Steaming Best for fruits that will be cooked before use Follow directions in freezing publications 37Home Food Preservation

Freezing Vegetables  Select young, tender, high-quality vegetables.  Sort for size and ripeness.  Wash and drain before removing skins or shells.  Wash small lots at a time, lifting out of water. Do not soak.  Work in small quantities, preparing per instructions. 38Home Food Preservation

Preventing Flavor and Color Changes in Vegetables Water blanching Use 1 gallon water per pound of vegetables. Place vegetables in blanching basket. Lower into vigorously boiling water. Cover and begin timing. 39Home Food Preservation

Blanching Vegetables Steam Blanching Use kettle with tight lid and basket. Put 1 to 2 inches of boiling water in the bottom of pan. Vegetables should be in a single layer in basket. Start timing when covered. Takes 1-1/2 times longer than water blanching. 40Home Food Preservation

Blanching Vegetables Microwave Blanching (not recommended) Enzymes might not be inactivated. Does not save time or energy. Use specific directions and blanch small quantities at a time. After blanching, cool immediately in cold water. Change water frequently. 41Home Food Preservation

Types of Pack for Vegetables Dry Pack Pack after blanched, cooled, and drained. Pack quickly, excluding air. 42Home Food Preservation

Types of Pack for Vegetables Tray Pack After draining, spread in a single layer on a shallow pan. Freeze firm. After first hour, check often. Pack quickly, excluding air. 43Home Food Preservation

Freezing Meats and Poultry  Keep meat or poultry and everything they touch as clean as possible.  Keep cold until frozen.  Never stuff poultry before freezing.  Store-bought meats must be over-wrapped.  Freeze meats and poultry using the drugstore or butcher wrap (drugstore wrap preferred except for irregular meat cuts). 44Home Food Preservation

Freezing Fish  Pre-treat as directed to control rancidity, flavor changes or loss of liquid.  Package using one of the following: Lemon-gelatin glaze Ice glaze Water 45Home Food Preservation

Lemon-gelatin Glaze  Mix 1/4 cup lemon juice and 1-3/4 cups water.  Dissolve 1 packet unflavored gelatin into 1/2 cup of this mixture.  Heat remaining mixture to boiling and add dissolved gelatin.  Cool, dip fish, wrap and freeze. 46Home Food Preservation

Freezing Prepared Foods  Many can be frozen.  Follow directions in a credible freezer publication. 47Home Food Preservation

Foods that Do Not Freeze Well  Cabbage, celery, cress, cucumbers, endive, lettuce, parsley, radishes  White potatoes  Cooked macaroni, spaghetti, rice  Egg whites  Meringue  Icings made from egg whites  Cream or custard filling  Milk sauces  Sour cream  Cheese  Mayonnaise or salad dressing  Gelatin  Fruit jelly  Fried foods 48Home Food Preservation

Thawing Foods for Serving Fruits Best if served with ice crystals present. Thaw:  In refrigerator -- 6 to 8 hours per pound of fruit in syrup  At room temperature -- 1 to 2 hours per pound  At room temperature in cool water -- 1/2 to 1 hour per pound  In microwave oven - follow manufacturer’s instructions. 49Home Food Preservation

Thawing Foods for Serving  Dry sugar packs thaw faster than syrup packs.  Unsweetened packs thaw the slowest.  When used in recipes, allow for added sugar and more juice. 50Home Food Preservation

Thawing Foods for Serving Vegetables Cook without thawing except partially thaw corn- on-the-cob and leafy greens. 51Home Food Preservation

Thawing Foods for Serving Meat, Poultry, and Fish Can be cooked when thawed or frozen (might 1-1/2 times longer if cooked frozen). Thaw:  In refrigerator  In microwave oven (follow manufacturer’s directions)  In cold water (keep water cold) 52Home Food Preservation

Shelf-Life of Frozen Foods 53Home Food Preservation

Vegetable Storage Temperature 0ºF 5ºF 10ºF 15ºF 20ºF 25ºF 30ºF Length of Storage 1 year 5 months 2 months 1 month 2 weeks 1 week 3 days 54Home Food Preservation

Emergencies 55Home Food Preservation

Freezer Emergencies  If power will be off, set freezer controls to 10ºF to -20ºF immediately.  Do not open door.  Foods stay frozen longer if freezer is full, well- insulated, and in cool area. Full freezer -- keeps 2 to 4 days Half full freezer hours 56Home Food Preservation

Freezer Emergencies  If power interruption will be longer than 1 to 2 days, use dry ice: 50 lbs -- keeps full 20 cubic foot freezer below freezing for 3 to 4 days 50 lbs -- keeps half-full freezer for 2 to 3 days  Keep dry ice on boards or heavy cardboard on top of food.  Do not touch dry ice.  Do not open freezer.  Ventilate room. 57Home Food Preservation

Refreezing Thawed Foods  Texture will not be as good.  General rule: Refreeze if freezer temperature is 40ºF or colder or if ice crystals are still present. 58Home Food Preservation

Best Advice for Freezing Freeze foods quickly. Set freezer temperature at -10ºF 24 hours before freezing foods. Spread packages out until frozen, then stack. Hold at 0ºF or colder for best quality. 59Home Food Preservation