Simple, Safe, Easy to LearnSimple, Safe, Easy to Learn

Freezing Fruits and Freezing Fruits and VegetablesVegetables

Today’s TopicsToday’s Topics

• Basics of freezing fruits and vegetables• Preventing fruits from discoloring• Blanching vegetables• Packaging frozen fruits and vegetables• Thawing methods for fruits and vegetables

Before preserving any food,

consider the types of foods your family enjoys

and the usefulness of the preserved

product in your lifestyle.

Basics for Handling Food SafelyBasics for Handling Food Safely

• Prevent bacteria from spreading through your kitchen– Wash hands:

• Warm water and soap for 20 seconds before and after handling food

– Sanitize: Cutting boards, utensils, and countertops

• Use a solution of 1 tablespoon of unscented, liquid chlorine bleach in 1 gallon of water

Freezing — OverviewFreezing — Overview

• Easy, convenient and the least time-consuming

• Slows growth of microorganisms and chemical changes

• Preserves the greatest quantity of nutrients

SelectionSelection

• Vegetables:– Choose young and tender – Over-mature may be hard, tough or flavorless

• Fruit:– Fully ripe, but firm– Under ripe may be bitter– Freeze soft, very ripe fruits as purées

Preparing Food for FreezingPreparing Food for Freezing

• Thoroughly wash all fruits and vegetables in cold water- DO NOT SOAK!

• Enzymes: – Vegetables:

• Destroyed by heat, blanching, before packaging and freezing

– Fruits: • Enzymatic browning • Controlled by ascorbic acid (vitamin C) or other

additives• Usually not blanched

What is the Freezing Effect?What is the Freezing Effect?

• Textural Changes:– Water freezes and expands foods – Ice crystals cause the cell walls of fruits and

vegetables to rupture, making them softer when thawed

– Vegetables with very high water content do not freeze well

• Ex. Celery, lettuce and tomatoes

– Vegetables with lower water content become more compact

• Ex. Spinach and broccoli

Freezing PointersFreezing Pointers

• Check freezer temperature – 0o F for best quality

• Freeze foods quickly

• Don’t stack food packages until they are solidly frozen

Fruit: Freezing OverviewFruit: Freezing Overview

• Frozen in many forms – Whole, sliced, crushed, juiced etc.

• Best quality- choose fully ripe, but firm, fruit– Immature or overripe produce lower quality

when frozen

Fruit: Preventing Darkening and Fruit: Preventing Darkening and DiscolorationDiscoloration

• Best for peaches, apples, pears and apricots

• Treat washed and sorted fruit with ascorbic acid (Vitamin C)– 1 tsp of ascorbic acid to one gallon of cool

water– Use commercial ascorbic acid mixtures

• i.e. Fruit Fresh™ (follow manufacturers directions)

• Lemon juice or citric acid solutions

Fruit: Types of PacksFruit: Types of Packs

• Syrup pack (see fact sheet)

• Sugar pack– Best for slices of soft fruits like strawberries

and peaches

• Dry (Tray) pack – Good for small whole fruits such as berries

• Unsweetened and water packs

• Artificial sweeteners

Fruit: Dry “Tray” PackFruit: Dry “Tray” Pack • Fruit pieces may be frozen individually, in single

layer, on a tray• Freeze until firm then package in rigid container

or bag

• Will pour out of container easily when frozen• Fruit pieces do not “clump” as when packed

directly into containers or with sugar syrup

Fruit: Thawing for ServingFruit: Thawing for Serving

• Timing:– Dry sugar packs thaw faster than syrup packs– Unsweetened packs thaw the slowest

• Pointers: – When used in recipes, allow for added sugar

and more juice– Not all fruits need to be thawed before using

Vegetables: Freezing OverviewVegetables: Freezing Overview

• Select young, tender, high-quality vegetables

• Sort for size and ripeness

• Wash small lots at a time, lifting out of water- DO NOT SOAK!

Vegetables: Water Blanching Vegetables: Water Blanching

• Primary method of destroying enzymes in vegetables

• Directions:– Boil water in a kettle with lid– 1 gallon water per 1 lb. of vegetables– Lower vegetables into vigorously boiling water. Put

lid on. Water should hardly stop boiling or return to a boil within a minute. Start timing the blanching as soon as water returns to a boil.

– At end of blanching time, quickly remove vegetables from boiling water and place in cold or ice water bath to stop cooking process.

Vegetables: Steam BlanchingVegetables: Steam Blanching

• Directions: – Use kettle with tight lid and basket– 1 to 2 inches of boiling water in bottom of pan– Vegetable should be in a single layer in

basket– Start timing as soon as the lid is on– Remove from kettle and place in cold or ice

water bath– Takes 1 to 1 ½ times longer than water

blanching- check times for each food

Vegetables: Cooling After Vegetables: Cooling After BlanchingBlanching

• After blanching in water or steam, cool immediately in cold water

• Change water frequently or use running water or iced water (1 lb. ice per 1 lb. vegetable)

• Cooling time should be the same as the blanching time

• Drain thoroughly

Vegetables: Types of PackingVegetables: Types of Packing

• Dry Packing– Pack after the vegetables are blanched, cooled,

and drained– Pack quickly, pushing air out of package as you

work towards top

• Tray Packing– After draining, spread pieces in a single layer on

a shallow pan– Freeze firm– Package quickly, pushing air out as you work

Vegetables: PackagingVegetables: Packaging

• Use freezer bags or rigid freezer-safe containers

– Squeeze air from bags before sealing– Leave ½ to I inch headspace for expansion in rigid

containers

• Use only moisture–proof, vapor-proof packaging designed for freezing

• Do not reuse cardboard containers or plastic containers from commercially prepared food products

• Label and date product

Vegetables: Thawing for Vegetables: Thawing for ServingServing

• Most vegetables can be cooked without thawing

• Corn-on-the-cob should be partially thawed before cooking so that it will heat all the way through

• Leafy greens cook more evenly if partially thawed

Recommended Storage TimesRecommended Storage Times

• Fruits– Most frozen fruits maintain high quality for 8 to 12

months– Unsweetened fruits lose quality faster than fruits

packed in sugar or sugar syrups

• Vegetables– Most vegetables will maintain high quality for 12

to 18 months at 0°F or lower – Use your home-frozen vegetables before the next

year’s crop is ready for freezing

What to do if the What to do if the freezer stops working:freezer stops working:

• Keep the freezer closed• If the freezer will be stopped for more than

24 hours use dry ice (if obtainable) or move the food to another freezer

• Thawed fruits that still have ice crystals can be refrozen or used in cooking, baking and making jams and jellies

• Vegetables containing ice crystals or at 40 ° F or below can be refrozen– Thawed vegetables should be thrown out

SummarySummary

• Freezing fruits and vegetables is a safe, easy way to preserve foods

• Wash all fruits and vegetables thoroughly

• Follow blanching charts for vegetables

• Use proper procedures and equipment, including freezer-safe materials

• Use the freezing process that works best for your family meal needs

Questions?

“This material has not been peer-reviewed for statewide distribution -- blind peer review pending.”

References:References:Angell, D., & Shertzer, J.(2009) Freezing Fruits. Cooperative Extension, The

Ohio State University.

Angell, D., & Shertzer.J.(2009) Freezing Basics. Cooperative Extension, The Ohio State University.

Angell, D., & Shertzer, J. (2009) Freezing Vegetables. Cooperative Extension, The Ohio State University.

Andress, E., & Harrison, J. (2006) So Easy to Preserve (5th ed.). Cooperative Extension, The University of Georgia.