Obviously it is uneconomic for food and drink manufacturers to invest in the type of clean rooms used in medical packaging and the electronics sectors. However, they need to be aware of the dangers of dust and other debris entering the food packaging and bottling production line. There are two key issues to be addressed. The first is dust and other particulates getting on to the packaging materials which can then contaminate the food contents. The second is static which is created when materials such as film or paper move over rollers.
The three key sources of dust and debris are machines, people and the material being processed. For example, in-line slitters create slivers and dust particles, and operators contaminate through skin flakes, hairs and clothing fibres. Many foods also flake or create crumbs, which can be attracted by the static to the seal of the packaging.
Static is a big problem at the filling or packing stages, as whenever materials such as film or paper move over rollers, high static charges are generated. This is an obvious health and safety hazard but will also attract dust particles from any adjoining surface and from the air. This not only contaminates the packaging, but if particles also get trapped in the seal it will not be airtight. This can severely affect yields as such packaging will have to be destroyed.
Not only is static an issue for dry food, but problems also occur when filling food that is moist in context, as the packaging materials by design have a very low moisture vapour transfer rate to keep the products fresh inside of the package. These speciality packaging materials have the ability to generate and store static electricity which can cause food to stick to the heat seal area and attract airborne foreign matter as well. Furthermore, static and dust can affect the labelling of products. If the surface is not clean when screen printing on a bottle, for example, it can affect the print quality. Likewise static can mean that labels are not positioned properly as the static charge on a plastic bottle can effectively ‘push’ the label in a different direction resulting in a misplaced label and wastage.
So what solutions are available? To remove static, static neutralisation bars and ionised blowers would be most suitable for food manufacturers as they deal with the problem at the critical areas and can also be easily integrated into the production line.
They can also be used to ensure that dust and other particles are effectively removed from the packaging materials before they enter the production line. A roller made of a special elastomer material lifts particles down to one micron in size and these are transferred to an adhesive roll for disposal.
The key benefits of installing an efficient cleaning or anti-static solution is a production process free of static and contaminants, and substantially improved end of line yields, with some manufacturing companies experiencing as much as a 30percent decrease in waste. These solutions can also reduce wear and tear on machinery and extend the lifespan of equipment.
John Penman is managing director of Microclean Technologies, Glasgow, Scotland. www.microcleantech.com