Polystyrene is a synthetic polymer made from an organic compound called styrene. It is the main component of styrofoam and is widely used in packaging due to its easy moldability and cushiness.
One of the most commonly used polystyrene packaging products is foam packing peanuts. Made out of expanded polystyrene, these peanuts are used to provide cushioning for goods in transit as well as to fill out space in boxes.
Despite its ubiquitous usage, polystyrene has come under fire for its detrimental effects on the environment. The material is non-biodegradable; thus, it will persist in the environment, especially on our beaches and in the ocean.
Additionally, polystyrene contains harmful chemicals that can leach into our foods and cause health and reproductive problems. When exposed to sunlight, polystyrene releases these chemicals in a gaseous state, polluting the air and depleting the ozone layer.
Fortunately, a biodegradable foam made from humble cornstarch is on the way to replace polystyrene in our packaging.
What is cornstarch foam packaging material?
Cornstarch foam is a biodegradable, compostable, and water-soluble packaging or void-filling material manufactured from cornstarch and soybean oil.
Cornstarch foam has all of the benefits of polystyrene (i.e., cushiness, shock absorption, etc.) with the bonuses of a reduced environmental footprint and being sourced from an abundant and renewable resource in the form of corn.
Also read: Cornstarch packaging
What are cornstarch packing peanuts?
Cornstarch foam can be shaped into packing peanuts to serve as a void-filling material. These peanuts are 100% biodegradable, compostable, and readily dissolve in water, ensuring that they don’t end up in our lakes, rivers, and oceans.
Like their polystyrene counterparts, cornstarch packing peanuts are designed to interlock with each other within a package, filling gaps and providing additional compression, padding, and support during transit without adding more weight.
How is cornstarch foam made?
Cornstarch foam is simple enough to make at home. First, you must gather the following materials:
- One cup of cornstarch to start.
- One cup of water: Water acts as a binder and aids in the dispersion of ingredients. The volume of water can be adjusted as needed for the desired consistency.
- Two tablespoons of white vinegar: White vinegar aids in controlling the expansion of the foam.
- Two tablespoons of glycerin: Glycerin enhances the foam’s flexibility and stability.
- Two tablespoons of baking soda: Baking soda helps control the mixture’s pH levels while also improving the foam’s texture.
- Food Coloring (Optional): Adding a few drops of food coloring can make your foam stand out.
Once you have all of the necessary ingredients, follow the step-by-step instructions below:
- Mixing: In a bowl, combine one cup each of cornstarch and water, and mix thoroughly into smooth paste. Make that no lumps remain, if you want to give your foam the correct consistency.
- Heating: Put the mixing bowl on a stove or in a microwave, and heat the mixture on low (stove) or in short bursts (microwave), stirring frequently. Be careful not to overheat; you’ll want the mixture to become thick and resemble pudding.
- Stirring: Add two tablespoons of white vinegar, glycerin, and baking soda, respectively, to the mixture, stirring vigorously. Adjust the quantities slightly to achieve the perfect consistency in your foam.
- Molding: Pour the warm mixture into select molds. Different shapes and sizes can be used based on your needs.
- Setting: Leave the molded foam to cool down and set. Do not disturb it during this phase. The size and thickness of your foam will determine how it takes to fully set. Being able to wait for a few hours is a must.
- Curing: Once the foam has finally cooled and set, cure in a cool dry place for a day or two. This will help it harden and reach optimal durability.
And that’s how you can make your own cornstarch foam packaging at home!
Of course, the industrial process is on a much bigger scale and includes far more complex techniques such as extrusion, hot-mold baking/compression, microwave heating, freeze-drying/solvent exchange, and supercritical fluid extrusion. These methods produce cornstarch foam with different cellular structures and properties.
Uses of cornstarch foam
The versatility of cornstarch foam cannot be understated. Here are some practical applications it can be used in:
- Shipping and transport: First and foremost, cornstarch foam is used to protect fragile goods (e.g., glassware, porcelain, electronics, etc.) during shipping or transit. Packing peanuts are especially versatile, able to fit into packages of every size without extensive alterations to the packing materials.
- Food packaging: Cornstarch foam can be shaped into various types of food packaging, including clamshell containers and trays. The material is 100% food-safe and does not leach toxic substances into your meals, making it a healthier option for you.
- Agriculture: Researchers have been working on creating a biodegradable foam capable of capturing helpful bacteria to promote plant growth. This shows that cornstarch foam has the potential to not only create sustainable farming practices but also improve other scientific applications.
- Daily household use: Cornstarch foam has also found its way into our everyday household lives, transforming the way we interact with everyday items. For example, cornstarch can be used as a cushion filler.
- Storage and display: Cornstarch foam offers a safe and reliable means of storing delicate items such as sunglass lenses. It can even be placed on shelves to provide comfortable leverage for your products.
Advantages and disadvantages of cornstarch foam
Cornstarch foam has its fair share of pros and cons that buyers should be made aware of before they consider purchasing it.
Advantages
Cornstarch foam offers many attractive advantages to brands and consumers:
- Sustainable and eco-friendly: Cornstarch foam is made from renewable and plant-based sources, reducing environmental impact and promoting sustainability.
- Fewer greenhouse gas emissions: Cornstarch foam manufacture is a more energy-efficient process that uses up fewer resources. As such, the material’s production has a reduced carbon footprint compared to polystyrene.
- Biodegradable: Cornstarch foam is biodegradable, meaning it naturally breaks down over time, minimizing waste and reducing environmental pollution.
- Compostable: After it has done its job, cornstarch foam can be sent to a dedicated composting facility to be turned into usable fertilizer. With the right temperature and moisture, this foam can be totally decomposed within minutes!
Read: Biodegradable vs compostable products
- Non-toxic: Cornstarch foam does not leach harmful chemicals into your food, thus making it suitable for food packaging.
- Water-soluble: Cornstarch foam can be dissolved in water, ensuring that it does not end up in the ocean or clog up our drainage pipes.
- Cushioning: Cornstarch foam provides excellent cushioning properties, protecting fragile items during transport or shipping.
- Shock absorption: Cornstarch foam offers high shock absorption, minimizing the risk of damage to delicate items.
- Versatility: Cornstarch foam is versatile and can be used for various applications, such as packaging electronics, glassware, or delicate items.
- Customizability: Cornstarch foam can be easily molded or shaped to fit specific items, providing a customized and snug fit for optimal protection.
- Water-resistance: While not completely waterproof, cornstarch foam offers a certain degree of water resistance, protecting items from light moisture.
- UV-resistance: Cornstarch foam packaging is resistant to UV radiation from the sun, providing an extra layer of defense for goods.
- Low flammability: Cornstarch foam is designed with low flammability in mind, reducing its fire hazard risks.
Disadvantages
Despite its many benefits, cornstarch foam has its fair share of disadvantages as well:
- Heavier weight: Compared to polystyrene, cornstarch foam is heavier. Thus, it may increase transportation and shipping costs.
- More expensive production: Being a relatively new product, cornstarch foam manufacture is comparatively costly. As a side-effect of this higher production cost, it is also more expensive than polystyrene products.
- Recycling difficulties: While polystyrene products are easy to recycle, it is significantly harder to do the same for cornstarch foam.
- Heavy metal contamination: While largely non-toxic and food-safe, cornstarch foam may leach heavy metals when disposed into soil or water without proper treatment.
- May affect food production: Being derived from a staple crop, increasing production and usage of cornstarch foam may disrupt the global food supply chain.
- Acidic: Composting large amounts of cornstarch can make the soil acidic.
- Limited infrastructure: Because cornstarch as a packaging material is relatively new, there are currently only a few infrastructures to support its manufacture, composting, or recycling.
Why is cornstarch foam a better alternative to polystyrene?
Cornstarch foam is ultimately a far superior alternative to polystyrene, offering the same practical benefits without the more glaring environmental cons.
Unlike polystyrene and its derivatives, cornstarch foam is 100% biodegradable and water-soluble. Because of this, the material will not continue to pose a threat to the environment, wildlife, and people.
On top of that, cornstarch is derived from corn, a staple crop that is grown in huge quantities on many different continents. As such, manufacturers are in full supply of the material.
Where can you buy cornstarch foam?
Bulk supplies of cornstarch foam and cornstarch packing peanuts can be purchased from major online retailers such as Shopee.
FAQ
Is cornstarch foam recyclable?
No. Cornstarch foam has no recycling value and cannot be reprocessed at recycling centers.
Care must be taken to ensure that cornstarch foam is separated from recyclable materials and avoid cross-contamination.
Is cornstarch foam biodegradable?
Yes. Being derived from plant-based materials, cornstarch foam can be decomposed by the natural actions of microorganisms. Additionally, it can also dissolve when submerged in water.
Is cornstarch foam compostable?
Yes. Cornstarch foam can be composted but requires very specific temperatures (at least 140°F), humidity levels, and large amounts of microbes. Because of this, it must be sent to a commercial composting facility and is not suitable for home composting.
Is cornstarch foam non-toxic?
Cornstarch foam by itself is non-toxic and food-safe. However, it does contain trace amounts of heavy metals.
While these miniscule amounts are largely harmless, if allowed to build up in the environment, they can lead to significant problems down the line.
As such, proper treatment and disposal of cornstarch foam is required to prevent this issue from arising.
Is cornstarch foam flammable?
Cornstarch foam has a low flammability, reducing its fire hazard risks.
However, when burnt, the foam may emit an acrid smell.
Will cornstarch foam replace polystyrene?
Yes. Cornstarch foam has the potential to totally replace polystyrene in all of its practical applications, from shipping to takeaway food.
As consumers become more environmentally conscious and continue to seek out sustainable alternatives to plastic and styrofoam, cornstarch foam has a high chance of taking over in the foreseeable future.
Unlike polystyrene, which is derived from non-renewable petroleum, cornstarch is made out of corn, a staple crop grown in abundance throughout the world. Thus, it has little chance of depleting and will continue to remain in abundant supply.
Shifting to cornstarch foam
Currently, cornstarch foam is primarily used in shipping and transportation. However, it has shown much promise as a substitute for styrofoam in food packaging.
Compared to styrofoam, cornstarch foam offers the same benefits of being lightweight, durable, and easy to store. But being made from plant-based materials, cornstarch foam is biodegradable, compostable, and even water-soluble. Qualities that ensure it does not remain in the environment.
Cornstarch foam is also better for our health as it does not contain any toxic chemicals. As such, there is no risk of harmful chemicals leaching into our meals.
Overall, there is still room for improvement, and further investments are required to make cornstarch foam truly sustainable. And by making the shift to it, your brand will better advertise the benefits of this material and help raise consumer awareness as well.
So don’t get left behind and join the cornstarch foam trend now!
