Food for thought

25 October, 2016

As discussed extensively in the media since 2010 and published in several of Beko Technologies’ own marketing bulletins, the food industry continues to pursue the aim of preventing and eliminating mineral oil contamination in food products.

In recognition of the growing importance of this topic, the British Compressed Air Society (BCAS) has published a ‘Best Practice Guideline 102’. This guideline was produced in association with the food/beverage industry requirements to outline the pre-requisite programme and where applicable HACCP processes to give the users the tools they need to achieve this critical part of the manufacturing process.

Greater risk

In our experience compressed air contamination is generally only considered during the packaging phase of manufacturing. However, contamination of compressed air through direct or indirect contact with food poses a much greater risk, and therefore a potential hazard.

Compressed air is used in most food and beverage production processes.

It is often used to transport or to mix products, purge moulds, clean canisters and containers, and also used in the direct production of food products. As a result, it comes into direct contact with the actual end product.

What is more, compressed air can come into indirect contract with food through packaging materials such as containers, bottles, cartons, etc., which are then used to package the food.

Below is a short overview of how compressed air is produced and how mineral oils can be transferred into foods:

• Oil-injected rotary screw compressors are commonly used when it comes to producing compressed air.

• ‘Oil-injected’ means that mineral oil is used in the compression chamber to cool and seal the air-end, thereby contaminating the compressed air with this mineral oil. After the compressor is used, the compressed air is usually filtered to reduce the level of oil contamination and other components are used to reduce the moisture content and particle levels.

• Oil-free compressors are also often used in the food industry. In the oil-free compression method, no oil is directly added to the compressed air in the compression process. However, carbon dioxide from the atmosphere that will contain varying levels of contamination – e.g. through not fully combusted diesel, emissions from industrial plants, etc. – is sucked up and compressed during the air generation process. As a result, even compressed air production using the oil-free method requires corresponding processing to reduce the carbon dioxide content, a fact that users are often not aware of.

In view of the compressed air applications that pose a risk of contaminating foods with mineral oil, Beko Technologies recommends online measurement procedures to ensure that compressed air is monitored at all ‘Critical Control Points’ whether it be contact and non-contact with food stuffs.