Through our deep understanding of both quality and safety requirements, Linde has developed a range of solutions for many products and processing stages, from nitrogen blanketing, purging and sparging, to fluffing and hydrogenation.
Oxidation refers to a chemical reaction where atmospheric oxygen attacks the fat acid chains of triglyceride molecules. The oxygen (O2) attack can take place at ambient temperatures or below (i.e. during normal storage of oils or finished food products). It can also occur at elevated temperatures, such as during processing or deep-fat frying.
In order to protect the oil and improve oil stability, oxygen should never come in contact with the product at any stage of the production process. In line with the worldwide trend towards the replacement of harsh physical/chemical preservative methods with less severe alternatives, the food industry is increasingly relying on nitrogen (N2) to resolve the oxidation challenge.
Nitrogen is a chemical element. Because it is an inert gas, it does not interact directly with the product. It is used to displace atmospheric air (and thus oxygen) and water vapour to avoid oxidation. There are two main processes for replacing oxygen with nitrogen: sparging to remove the dissolved oxygen; and blanketing to assure the absence of oxygen in the headspaces. Sparging involves injecting a gas into a liquid and is applied to remove oxygen from a product.
The process used will obviously depend on the type of product and the processing stage. For example, nitrogen blanketing is beneficial for the holding tanks for intermediate oils and the storage tanks for crude oils and finished oils.
There is a third process called fluffling. This is used widely in the fats and mayonnaise industry. The main objective of this technique is to change the texture of the product. It is mainly applied to fats for bakery products to assure the desired density and avoid the presence of air.
Nitrogen is an inert gas that does not interact directly with the product and is used to displace atmospheric air (and thus oxygen) and water vapour to avoid oxidation.
Applications we support:
- Blanketing, purging, sparging