Today, more farmers are being encouraged to use barrier films, which have gained popularity and appreciation within the agricultural industry thanks to their properties that help improve the quality and preservation of the crops.
The benefits of using “barrier” films -in this case to preserve forage- are multiple. However, farmers need to pay attention since it is becoming increasingly common to find plastic films on the market that claim to belong to the “oxygen barrier” type when in fact they don’t reduce, or block, oxygen transmission. Additionally, one of the factors considered at the time to choose plastic films as an alternative is the investment that will be made, and at this point it is essential to be certain that you are acquiring what you are looking for because nobody wants to take home the wrong product ultimately resulting in a loss of capital both because of an inadequate product and an increase in wastage of fodder.
There are several barrier film options out of which the use of plastic barrier films that reduce the entry of oxygen is the most recommended as a way to increase farm profits. According to the article The importance of using Oxygen barrier films, this is basically a measurement to determine how effective the material acquired is when it comes to preventing oxygen entry. It is worth mentioning that when the OTR factor is lower, the oxygen permeability of the plastic will also be lower, which will allow to achieve better results. What is paramount to protecting the quality of forage is to avoid as much as possible that the oxygen flows through the first meter of silage pile.
Expert opinion about barrier films:
To know all the details about plastic barrier films, we talked to Daniel Fiersbach, Animal Nutrition expert, to clarify the most frequent doubts about these plastics:
- What is gas permeability?
It is a quality of plastics that can be measured in cm ³/m² x d x bar, which translates into cubic centimetres (cm³) divided by square meters (m²) per day and at a specific pressure (normally 1Mpa). To get an idea about this, let’s imagine a lump of sugar that is usually 1 cm³ in size. The permeability of gases of the PELD will be proportional to its thickness, in other words, the thicker the film, the less permeable it is, and the less gases will pass through it. The recommendation of the Association of Farmers of Germany (DLG) is that the value in a silage film does not exceed 250 cm ³/m² x d x bar, that is, no more than 250 lumps of sugar, representing the gas, would pass per m² of plastic in one day.
- What are barrier films?
They could be defined as those films that include the capacity to be permeable to gases below 10 cm ³/m² x d within their qualities. These values are achieved through the EVOH or PA polymers. In general, films with a permeability higher than 10 cm3 would not be considered “true” barriers. If we consider the lumps of sugar as an example: it is not the same passing 125 lumps than just 10.
- Can I distinguish barrier films from regular plastics?
It’s not possible at first glance. The EVOH or PA layer is much thinner than a human hair and has the same colour as the rest of the plastic. However, there are indications that may be helpful to distinguish one from another, although there is no guarantee:
Price: Barrier films tend to have a considerably higher cost than regular films.
Layers: They are usually made with five additional layers, 3-layer-films with barrier effects are not frequently found.
We also recommend you read other articles related to the storage of food or agricultural products such as advantages of silo bags vs. traditional silage and how to minimize mycotoxin problems storing animal food.