Freezing

1. Freezing Rick Sloan FCS Agent

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

3. Principles of Freezing Home Food Preservation 3

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

5. 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. Home Food Preservation 5

6. 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. Home Food Preservation 6

7. 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. Home Food Preservation 7

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

9. Freezers Home Food Preservation 9

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

11. 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 -- 35 pounds of frozen food per cubic foot or usable space. Home Food Preservation 11

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

13. 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 Home Food Preservation 13

14. 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 Home Food Preservation 14

15. 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. Home Food Preservation 15

16. Packaging Materials Home Food Preservation 16

17. 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 Home Food Preservation 17

18. 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 Home Food Preservation 18

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

20. Freezing Foods Home Food Preservation 20

21. 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. Home Food Preservation 21

22. 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. Home Food Preservation 22

23. 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. Home Food Preservation 23

24. 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. Home Food Preservation 24

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

26. 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. Home Food Preservation 26

27. 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. Home Food Preservation 27

28. 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 Home Food Preservation 28

29. 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. Home Food Preservation 29

30. 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. Home Food Preservation 30

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

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

33. 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. Home Food Preservation 33

34. 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 Home Food Preservation 34

35. 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. Home Food Preservation 35

36. 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 Home Food Preservation 36

37. 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 Home Food Preservation 37

38. 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. Home Food Preservation 38

39. 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. Home Food Preservation 39

40. 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. Home Food Preservation 40

41. 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. Home Food Preservation 41

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

43. 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. Home Food Preservation 43

44. 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). Home Food Preservation 44

45. 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 Home Food Preservation 45

46. 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. Home Food Preservation 46

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

48. 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 Home Food Preservation 48

49. 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. Home Food Preservation 49

50. 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. Home Food Preservation 50