Quick Answer
Yes, cardboard can generally go in the freezer as long as it meets a few requirements:
- It must have a wax coating to make it moisture-resistant.
- It shouldn’t contain any glue or paper that could get damaged.
- It should be sturdy cardboard that won’t bend or warp.
Cardboard is regularly used for freezer storage when properly prepared. Wax-coated cardboard blocks moisture and prevents freezer burn. Sturdier cardboard boxes are better than flimsier boxes for the freezer. Avoid cardboard with glues or paper layers that may crack. Freezer temperatures won’t destroy the cardboard itself.
Does Cardboard Get Ruined In The Freezer?
Plain cardboard can become damaged in the freezer, but cardboard designed for freezing conditions holds up well. Here’s a more in-depth look:
Plain Cardboard
Regular cardboard boxes and containers are not suitable for the freezer. The frigid, moisture-free environment will cause plain cardboard to become brittle and crack. Any condensation inside the cardboard will freeze, expand, and break down the fibers.
Wax-Coated Cardboard
Cardboard boxes and trays with a wax coating protect against freezer damage. The wax makes the cardboard water-resistant. This prevents ice crystals from forming inside the cardboard and rupturing it. Wax also stops moisture migration that leads to freezer burn.
Cardboard Strength
Thicker, more dense cardboard withstands freezing better than thinner, weaker cardboard. Heavy-duty cardboard boxes are ideal for the freezer. Thin cardboard may turn brittle and fragile at freezing temperatures.
Moisture-Resistant Cardboard
Look for freezer-grade cardboard treated to be moisture-resistant. It may have a plastic coating or be infused with polymers. This specialty cardboard remains intact in freezing conditions. Avoid regular cardboard that can absorb moisture.
What Types of Cardboard Can Go In The Freezer?
These types of cardboard are good options for freezing:
- Wax-Coated Cardboard – Has a wax coating to repel moisture.
- Freezer Cardboard – Treated for freezer use and moisture-resistant.
- Thick, Durable Cardboard – Sturdy boxes made for packing, moving, etc.
- Poly-Coated Cardboard – Coated in polymers to prevent freezing damage.
- Non-Corrugated Cardboard – Made from pressed cardboard sheets.
Avoid using:
- Regular Cardboard – Absorbs moisture and cracks in the freezer.
- Cardboard Containers – Food containers lack moisture protection.
- Cardboard with Glue – Glue can become brittle and crack.
- Flimsy Cardboard – Bends, warps, and breaks in the freezer.
- Corrugated Cardboard – The ridges can crack as moisture expands.
The most suitable cardboard for freezing is durable, moisture-resistant, and free of glues. Wax coatings are ideal for blocking moisture. Thick, sturdy cardboard also withstands freezing well. Avoid paper-based cardboard that can crack.
Does Wax Coated Cardboard Go In The Freezer?
Yes, wax coated cardboard is one of the best options for freezer use. The wax coating makes the cardboard water-resistant. This prevents condensation from saturating the cardboard when it shifts between the cold freezer and warmer ambient temperatures.
Wax coatings provide two main protections:
1. Moisture Barrier
The wax coating forms a moisture barrier that keeps water and condensation from being absorbed into the cardboard. This prevents ice crystals from expanding inside the cardboard and causing it to crack.
2. Freezer Burn Barrier
By blocking moisture migration in and out, a wax coating helps prevent freezer burn. It keeps air from drying out food surfaces. The wax also stops dampness from leading to icy buildup on foods.
Some key advantages of wax coated cardboard for the freezer include:
- Won’t crack or warp due to moisture.
- Prevents freezer burned food.
- Wax withstands freezing temperatures.
- Low risk of bacteria growth.
- Can be reused many times.
Wax-coated cardboard is inexpensive and reusable. It’s the ideal choice for freezer storage containers and ice cream cartons. The wax coating reliably protects the cardboard in the freezer.
What Precautions Should Be Taken With Cardboard In The Freezer?
Use these precautions with cardboard in the freezer:
Choose High-Quality Cardboard
Pick wax-coated or other moisture-resistant cardboard. Avoid thin, cheap cardboard prone to tearing. Sturdy, thick cardboard is best.
Inspect for Damage
Check cardboard for wax cracks or weaknesses before reuse. Look for evidence of moisture damage. Discard any compromised cardboard.
Allow to Adjust to Temperature
Let cardboard adjust to freezer temperatures before filling. Don’t immediately put hot foods in. Sudden temperature changes stress the cardboard.
Avoid Opening Frequently
Limit openings to maintain stable freezer temperatures. Frequent openings cause temperature fluctuations that contribute to moisture issues.
Rotate Out Old Cardboard
Replace cardboard boxes every few years as needed. Cardboard weakens over time. Rotate in fresh boxes to ensure durability.
With high-quality freezer cardboard and some basic precautions, cardboard boxes and trays can last for many years in the freezer. Just avoid sudden temperature changes and moisture damage.
How Long Does Cardboard Last In The Freezer?
Properly prepared cardboard typically lasts 1-5 years in the freezer. Heavy-duty cardboard boxes may last up to 10 years. Factors affecting cardboard’s freezer lifespan include:
Cardboard Quality
– Thick, sturdy cardboard lasts longer than flimsy cardboard.
– Wax-coated cardboard survives better than plain cardboard.
Freezer Temperatures
– Colder freezers prolong cardboard life. Set temperatures between 0°F to -10°F.
Opening Frequency
– Frequent openings shorten lifespan by allowing temperature fluctuations.
Contents
– Heavy items can shorten lifespan by crushing cardboard.
– Moisture from icy foods also reduces lifespan.
Damage
– Cracks, dents, and moisture damage accelerate deterioration.
With high-quality thick cardboard and stable freezing temperatures, most cardboard boxes, trays, and dividers should last 2-5 years. Replace cardboard showing any signs of damage. Avoid cardboard failure by inspecting annually.
Does Freezer Temperature Damage Cardboard?
Freezer temperatures do not directly damage or destroy cardboard. Cardboard is unaffected by cold alone. However, indirect moisture damage promoted by freezing can deteriorate cardboard over time.
Here’s how cardboard is impacted by freezer temperatures:
No Thermal Damage
Freezing temperatures do not damage cardboard through cold alone. Cardboard does not become brittle or weak solely from freezing cold.
Moisture Damage
Temperature fluctuations allow moisture migration into cardboard. This moisture freezes inside cardboard, causing cracking and ice expansion damage.
Accelerated Aging
The cold accelerates the natural aging and weakening of cardboard over many years. Brittleness increases faster than at room temperature.
Compression Damage
Hard frozen items can compress and deform cardboard boxes over time. The cold cardboard loses structural strength.
While freezing itself won’t destroy cardboard, the cold environment does lead to faster deterioration from moisture and aging. Limit temperature fluctuations and avoid moisture to maximize cardboard’s freezer lifespan.
How To Keep Cardboard From Getting Soggy In The Freezer
Use these tips to prevent cardboard from getting soggy in the freezer:
Choose Wax-Coated Cardboard
The wax coating blocks moisture from saturating the cardboard. It creates a water-resistant barrier.
Allow Time To Adjust To Temperature
Let cardboard adapt to freezer temps before filling. Rapid temperature drops can cause interior condensation.
Fill With Already-Frozen Items
Don’t put hot foods straight into the cardboard. Frozen foods won’t release as much moisture.
Avoid Opening the Freezer Frequently
Openings allow moist air influx and temperature fluctuations. Minimize openings.
Insulate Cardboard Exteriors
Wrap an additional moisture barrier like plastic wrap or aluminum foil around the cardboard.
Use Freezer-Grade Plastic Bags
Double bag foods in high-quality plastic before putting them in cardboard boxes.
Repair Any Wax Cracks
Use freezer tape to seal any small cracks or deficits in wax coatings.
With planning, even non-coated cardboard can avoid getting soggy. Limit moisture exposure by double wrapping foods and minimizing temperature fluctuations.
Can You Freeze Liquids In Cardboard Containers?
It’s not recommended to freeze liquids in cardboard containers, even if coated in wax. The cardboard is still at risk of moisture damage. For liquids, use these freezing guidelines:
Small Liquid Amounts
– Place in plastic freezer bags first. Exclude as much air as possible. Then put bag in cardboard box.
Large Liquid Amounts
– Pour liquid into plastic containers or glass jars approved for freezing. Leave headspace.
Expandable Liquids
– Use rigid plastic containers and leave ample headspace. Liquids like water expand as they freeze.
Alcoholic Beverages
– Only freeze in glass containers tolerant of alcohol’s expansion. Do not use plastic.
Soups, Sauces
– Allow to cool completely before freezing. Freeze in plastic containers or bags.
The best practice is to avoid direct contact between liquids and cardboard. Freeze liquids in plastic or glass first. Then place these sealed containers in cardboard as extra protection.
Does Humidity Affect Cardboard In The Freezer?
Yes, high humidity significantly accelerates cardboard damage in the freezer. Excess moisture causes condensation, saturation, and freezing damage to cardboard:
Condensation
Humidity condenses into liquid water on cold cardboard when the freezer is opened. This introduces damaging moisture.
Saturation
Cardboard absorbs ambient humidity each time the freezer is opened. Over time, the cardboard becomes saturated.
Freezing
Any water absorbed into the cardboard will freeze. Ice expansion causes cardboard to crack and split apart.
Mold Growth
Damp cardboard provides favorable conditions for mold to grow. This can ruin cardboard and contaminate food.
To limit humidity damage, use wax-coated cardboard, minimize opening frequency, and maintain a well-sealed freezer. Also replace any cardboard showing water stains or damage. Keeping humidity low preserves cardboard strength and integrity.
Does Cardboard Absorb Moisture In The Freezer?
Regular cardboard will absorb moisture from the freezer environment. Over time, repeated humidity and condensation exposure saturates the cardboard. However, wax-coated cardboard is specially formulated to prevent moisture absorption.
Here’s how different types of cardboard handle moisture:
Regular Cardboard
The fibrous texture of regular cardboard acts like a sponge to soak up ambient humidity each time the freezer is opened. It becomes damp and soggy.
Wax-Coated Cardboard
The wax coating blocks moisture absorption by creating a protective barrier. Condensation beads up instead of soaking in.
Plastic-Coated Cardboard
Plastic polymer coatings also prevent the cardboard underneath from absorbing moisture. The plastic remains waterproof in freezing temperatures.
Freezer Cardboard
Specialized freezer cardboard is infused with vinyl or other coatings to make it moisture-resistant. This prevents absorption.
Plain, untreated cardboard will gradually become saturated with moisture. Only wax or plastic-coated cardboard provides true water protection and avoids this deterioration in the freezer’s humid environment.
How To Waterproof Cardboard For The Freezer
To waterproof cardboard for freezing, use these techniques:
Apply Wax Coating
Melt paraffin or candle wax and spread/brush multiple coats on the cardboard. Allow to fully dry between layers.
Use Plastic Wrap
Wrap the cardboard box tightly in plastic wrap, securing it completely to the box.
Coat With Polythene
Brush polythene wax evenly on all surfaces to penetrate the cardboard. This is available online and at hardware stores.
Line With Plastic Bag
Insert a plastic freezer bag inside the cardboard box. Seal foods first in a second bag.
Use Insulating Tape
Apply special freezer tape over any seams, joints, and edges to seal out moisture.
Create Composite
Glue sheets of plastic or foil to the interior sides facing contents to add a moisture barrier.
With creative use of plastic, wax, and tape, it’s possible to waterproof regular cardboard for safe freezing. Specialty freezer cardboard is designed to be moisture-resistant.
Does Cardboard Need To Be Dry When Going Into The Freezer?
Yes, cardboard put into the freezer should always be completely dry first. Any residual moisture or condensation will damage the cardboard:
– Wet cardboard placed in the freezer will freeze solid, causing permanent distortion.
– Damp cardboard promotes mold growth in the cold, moist environment.
– Moisture inside cardboard expands into ice crystals when frozen. This ruptures the cardboard’s fibers from the inside.
– Water staining indicates the cardboard has absorbed humidity and needs replacement.
To avoid moisture issues, allow cardboard to fully air dry after cleaning before use in the freezer. Never let cardboard sit wet – wipe up spills or rinse water immediately. Check for hidden inner moisture by bending the cardboard – any cracking indicates water absorption.
With vigilance, even non-coated cardboard can be dried fully. However, wax-coated cardboard has moisture resistance built-in as an added safeguard. Keeping cardboard dry before freezing is fundamental to preventing freezer damage.
Does Cardboard Get Freezer Burn In The Freezer?
No, cardboard does not itself get freezer burn in the freezer. Freezer burn only affects foods. However, damaged or wet cardboard can indirectly cause freezer burn:
– Cardboard saturated by humidity can freeze against food. This causes dehydration and ice crystals – two factors behind freezer burn.
– If cardboard cracks or punctures, air can reach food causing oxidation (drying out).
– Weak cardboard can crush, exposing food surfaces to air.
– Any moisture migration through the cardboard promotes freezer burn.
While cardboard doesn’t suffer freezer burn, compromised cardboard accelerates freezer burn in other items. Using wax-coated or moisture-resistant cardboard minimizes this risk. Undamaged, high-quality cardboard is a good barrier against freezer burn.
Does The Freezer Kill Germs On Cardboard?
While freezing doesn’t reliably sterilize cardboard, the cold temperatures do help suppress microbial growth. Freezing makes conditions harder for germs but doesn’t guarantee full disinfection.
Lower Microbial Activity
Cold temperatures significantly slow the reproduction and metabolism of bacteria, mold, and other microbes. This reduces their damage potential.
No Growth
The near-freezing temperatures prevent microbial growth. Germs cannot actively multiply under frozen conditions.
Not All Germs Die
Many germs will enter a dormant state but not die completely. They resume growth after thawing.
Freezer Burn Kills Some Germs
The dehydrating effects of freezer burn can be detrimental to some bacteria. However, freezer burn damages food quality.
For food safety, cardboard should not directly touch moist foods for extended freezer storage. Use plastic wrap or wax layers between the cardboard and contents. This prevents germ transfer.
While freezing cardboard with food may reduce overall germ levels due to dormancy, the best practice is to keep cardboard dry and layered away from direct food contact.
Conclusion
Cardboard is best suited for freezing when it is wax-coated, moisture-resistant, and structurally sturdy. These qualities prevent the damaging moisture absorption and cracking that plain cardboard is prone to in the cold, humid freezer environment. With proper preparation and careful moisture management, cardboard can safely provide many years of freezer storage and stackability. Using appropriate precautions and high-quality freezer-grade cardboard minimizes risks to the cardboard and frozen contents.
