In just a few years we have gone from collect plastic bags free in every store We're now checking labels, seals, and materials to see how much our products pollute. In addition to paying for bags, we're also concerned about their impact on the planet and are becoming familiar with terms like biodegradable, recyclable, water-soluble, and compostable.
Within this new scenario, the compostable bags They have become the star option Suitable for both businesses and homes. They have a softer feel, a more "natural" appearance (often in cream or off-white tones) and are designed to decompose into compost under suitable conditions, instead of remaining for centuries in landfills or oceans.
What exactly is a compostable bag?
When we talk about compostable bags, we are referring to packaging made from materials of plant origin and specific bioplastics which, after use, can be biologically degraded into water, carbon dioxide, mineral salts and biomass, without leaving toxic residues or recognizable pieces of plastic.
The composting process implies that decomposition takes place in controlled conditions of humidity, temperature and oxygen, usually in composting plants or well-managed domestic systems, and that the end result is a compost that can be used as a quality organic fertilizer.
In order to truly be called compostable, these bags must comply very specific criteria for disintegration, biodegradation and absence of hazardous substancesIt is not enough for them to be broken into small pieces; they must be completely transformed into compounds that can be assimilated by the soil and microorganisms.
What are compostable bags made of?
The base of most compostable bags is the starch or starch of vegetable origincombined with other biodegradable polymers that provide strength and flexibility. Among the most common materials are formulations such as PLA and PBAT.
PLA (polylactic acid) is a bioplastic derived from renewable resources such as corn, potatoes, or sugar caneIt provides rigidity and transparency in certain formats, and is also suitable for food contact in many applications.
PBAT (polybutylene adipate terephthalate) is a biodegradable polymer used to give the bag elasticity, tear resistance and impermeabilityIn combination with PLA and vegetable starch, a material is obtained that behaves very similarly to conventional plastic in use, but which can be composted under suitable conditions.
References to bags are frequently found in the market. PLA + PBAT from corn starchespecially in food formats, as this mixture offers a good balance between mechanical performance and certified compostability.
Where and how are compostable bags used
Compostable bags are not limited to the typical shopping bags with handles. There are more and more. formats designed for very specific needs in supermarkets, hospitality, retail and domestic use.
A very common example is the Roll bags for fruit and vegetables in supermarkets or traditional marketsThey are usually flat bags, without handles, placed near the fresh produce section so that customers can serve themselves apples, potatoes, bread rolls or nuts.
This type of bag is usually found in paper core rolls (for example, diameters of around 25-31 mm) for easy placement in dispensers or roll holders. The roll format allows for quick, hygienic, and efficient service, as they are torn off one at a time and remain tidy.
Regarding sizes, it is common to find measurements such as 30 x 40 cm and 35 x 45 cm in rolls of 400 and 300 units respectively, with thicknesses around 10-12 microns and weights per bag of just a few grams. Despite their lightness, they are designed to easily support the weight of fruits, vegetables, or other loose foods.
In addition, they are usually white or cream-colored bags with a identification print of type "Bio" or similar in green on one side, to make it visible to the user that they are using a compostable product suitable for separating the organic fraction.
Resistance and performance compared to conventional plastic bags
A recurring question is whether compostable bags are as durable as traditional plastic bags. The truth is that they are. Modern compostable bags perform the same basic functions than conventional polyethylene bags in most everyday uses.
In terms of everyday use, these bags are flexible, resistant and waterproofTherefore, they are perfect for carrying groceries, packaging food, or collecting organic waste without breaking at the slightest touch.
In the specific case of compostable bags for organic waste, it is advisable to adopt a small change of habit: It is not advisable to accumulate organic waste for too many days inside the same bag, because the degradation process itself can begin to be noticeable after a few days, especially in warm and humid environments.
This does not mean the bag is fragile or of poor quality, but rather that it is designed to begin its degradation within a reasonably short periodTherefore, it is ideal to empty the organic waste bin regularly and not leave the bag at home for weeks on end.
When used to transport products or to package ready-to-eat foods, the experience is virtually identical to that of conventional plastic, with the added advantage of knowing that The end-of-life of the bag will be much less problematic for the environment..
Compostable bags for organic waste and domestic use
In many cities and towns, it has been implemented brown bin for organic wasteThis container is for fruit and vegetable scraps, coffee grounds, eggshells, stale bread, spoiled food scraps, and other waste that can be turned into compost.
For this type of waste, the option recommended by most administrations is to use certified compostable bagsThus, when the bag arrives at the treatment plant, the organic waste can be efficiently transformed into fertilizer, and the bag disintegrates and biodegrades along with its contents.
Using these bags makes housework much easier: it allows keep the organic waste bin cleanAvoid bad smells when closing the bag and transport the remains to the brown bin without spills.
Once at the composting plant, the mixture of organic waste and compostable bags undergoes aeration, humidity and temperature controlled processes so that microorganisms (fungi, bacteria, etc.) can transform everything into a stable and safe compost.
The end result is an organic fertilizer that can be used in agriculture, gardening or reforestation, provided that quality controls are met and no non-compostable materials have slipped into the container.
Differences between compostable, biodegradable and recyclable bags
One of the big problems with this topic is that concepts are often mixed up and we end up thinking that Biodegradable, compostable, and recyclable all mean the same thing., when in reality they are quite different things.
On the one hand, a biodegradable material is one that can decompose naturally thanks to microorganisms such as bacteria, fungi, or algae. Over time, this material is converted into nutrients, carbon dioxide, water, and biomass, under conditions that can occur in nature, although sometimes the process can take years.
Standard polyethylene bags, which have been the most common for decades, They are not biodegradable under normal conditionsHowever, some bioplastics made from renewable resources (such as potato starch) or certain special polyesters can biodegrade within reasonable timeframes.
To be considered truly biodegradable according to European standards, a bag must meet the following requirements: UNE-EN 13432 standard or equivalentwhich establish requirements on the degree of biodegradation, the maximum time to achieve it and the absence of toxic substances or heavy metals in the material.
The concept of recyclable is different: a recyclable material is one that can be to be industrially reprocessed to manufacture new productsFor this to happen, specific recycling plants, proper waste separation, and technical processes that transform the material into new raw materials are needed.
In this case, the transformation is not the direct result of the action of microorganisms, but of industrial processes managed by peopleMany conventional plastics are recyclable, although in practice they are not always recycled due to collection problems, mixing of materials, or lack of facilities.
Compostable bags occupy a special place: they are made with materials that can biodegrade and also be turned into compost in suitable facilities. This makes them especially interesting for managing organic waste and closing the nutrient cycle.
Compostable versus biodegradable: what are the differences?
Although all compostable materials are, by definition, biodegradable, Not everything biodegradable is compostableThis is the key point to understand in order to avoid falling into green marketing confusion.
The compostable one requires that the material can become useful fertilizer in a relatively short timeUnder controlled composting conditions, and without leaving visible residues or toxic components. This involves laboratory testing, certifications, and very specific technical requirements.
In biodegradable materials, the decomposition process can be considerably longer and doesn't always result in quality compost suitable for direct use in agriculture or gardening. Sometimes it simply means the material is It fragments and transforms very slowly in naturewithout strict process control.
The big difference is that in composting there is usually a organized human intervention (selective collection, composting plants, parameter control), whereas biodegradation can occur more spontaneously and dispersedly, often over longer periods of time.
That is why it is often said that All compostable products are biodegradable, but not vice versa.A bag may be designed to degrade in nature in X years, but not meet the requirements to produce a stable and safe compost in a few weeks or months.
Certifications and seals you should know about
To ensure that a compostable bag truly lives up to its promises, it's essential to look at the certifications and seals that appear on the packaging or technical data sheetNot all mentions of "eco" are equivalent.
One of the benchmark standards in Europe is the standard EN 13432This regulation governs the recovery of packaging materials through composting and biodegradation. Among other points, it stipulates that the material must disintegrate almost completely within a limited time and that the resulting compost must not contain harmful substances.
Products that comply with this standard usually bear seals awarded by recognized certification bodiesThese certifications independently verify that all technical and environmental requirements are met. They may be printed on the bag itself, on the roll, or on the supplier's documentation.
In addition to specific composting standards, some products may be certified under recycled content standards such as Global Recycled Standard (GRS)This standard focuses on ensuring that the recycled material used in a product has been verified throughout the entire supply chain.
In the case of GRS, the product is required to contain at least 50% certified recycled material To qualify for certain environmental labels or programs like Climate Pledge Friendly, tracking is carried out from the origin of the material to the final product, including social, environmental, and chemical requirements.
It is common for information such as the GRS seal to appear alongside the GRS label. certification body and certificate number, data that allows tracking and verifying the authenticity of the certification if you wish to delve deeper.
Specific examples of compostable bags for retail and hospitality
In the professional sector we find more and more compostable packaging solutions tailored to different types of businessesfrom fruit shops to restaurants with takeaway service.
In butcher shops, delicatessens, fruit shops, bakeries, pastry shops, ice cream parlors, cafes, catering and delivery services, or prepared food shops, many types of bags are used to carry food or vacuum-pack it, and in many cases, they are already available. certified compostable alternatives.
An interesting example is the compostable bags for vacuum sealingDesigned for establishments that are particularly environmentally conscious, these bags allow you to store and cook foods such as sauces, stocks, sautes, meats, fish, and other preparations.
This type of bag is usually made with materials such as PLA and PBAT, completely free of conventional plastic, with thicknesses around 75 microns to ensure resistance to vacuum pressure and cooking temperatures.
They are suitable for wide temperature ranges, for example from -30 ºC to +100 ºCallowing freezing and prolonged cooking (for example, up to about 22 hours at 90°C), and are normally sealed at temperatures that can be, depending on the model, between approximately 118°C and 125°C.
Regarding end-of-life treatment, these bags are designed to deposit in the brown container when they have contained organic remains, thus integrating into the organic fraction circuit and industrial composting.
Environmental impact compared to traditional plastic bags
Compostable bags represent a significant change from traditional plastic bags, whose Degradation time can reach 400-500 years in the environment, fragmenting into microplastics that are dispersed through soils, rivers and oceans.
Under suitable composting conditions, a compostable bag can to disintegrate and biodegrade completely in a few monthsIn some well-managed processes, timeframes of around 18 weeks are discussed for certain specific compostable bag formats.
The difference in time scale is enormous: compared to the centuries it takes for a polyethylene bag to disappear, A compostable bag integrates into the natural cycle in a matter of months.also providing usable organic matter for the soil if the composting process is well controlled.
This change not only reduces the amount of persistent waste in landfills and natural environments, but also helps to reduce pollution in rivers, beaches and cities, an increasingly visible and worrying problem.
It must be borne in mind, however, that the positive impact only materializes if a proper waste management: properly separate the organic fraction, use certified compostable bags and avoid mixing non-compostable materials in the brown bin.
Benefits for shops and businesses
For a business, choosing compostable bags is not just a matter of complying with regulations, but also a way to communicate environmental commitment to customersPeople increasingly value businesses that are concerned about reducing their ecological footprint.
Incorporating compostable bags in a supermarket, fruit shop, bakery or restaurant helps to normalize the use of more responsible materials It also subtly educates the buyer: the very feel, color, and printed messages on the bag remind them that there are alternatives to conventional plastic.
In addition, many manufacturers offer bags made with 100% recycled and 100% recyclable materials in certain ranges, and complement their catalog with compostable domestic and industrial garbage bags made with bioplastics that comply with the EN 13432 standard and display the corresponding seals on their technical data sheet.
For business, this translates into power align packaging policy with sustainability goals, improve their brand image and, in some cases, meet environmental certification requirements or their own climate commitments.
In a market where environmental awareness is on the rise, having access to Expert advice on what type of bag to use for each application (organic, freezing, vacuum packing, bulk sales, etc.) is a plus that many supplier companies already offer to their professional clients.
The importance of clear information for the user
For this entire transition to work, it is essential that those who use the bags have access to simple and understandable information on how to choose, use and properly dispose of each type of bag.
It is common to find in online stores and catalogs filters to select features (material, format, color, type of recycling, etc.) and systems that automatically display the references that meet the chosen criteria, thus facilitating the search for the professional or the end consumer.
It also explains in detail how they should be select quantities, measurements and options according to the needs of the business, and additional information is offered on certifications, specific materials (PLA, PBAT, vegetable starch) or bag thicknesses.
In the case of products certified under standards such as the Global Recycled Standard or EN 13432, the following usually appears: Reference to the certifying body and the certificate numberThis is important information for anyone who wants to verify traceability and regulatory compliance.
All of this is usually accompanied by cookie policies and legal notices that explain how the website and service are optimized, something common on any current page that offers information and sells products.
Taken together, compostable bags represent a logical evolution in the way we understand single-use packagingThey continue to offer the convenience and functionality we are used to, but add the advantage of being able to be integrated into the organic matter cycle with a significantly lower environmental impact, provided they are used, separated and managed properly.
