The meat and fish processing industries are known for their cleanliness; their protocols are based around a strict and stringent cleaning process after every operation so that products can be maintained at the required level of quality and safety for the retailer and eventually the buyer. Products which have been prepared under strict hygienic control have a longer shelf life and therefore have more value.
One of the ways in which meat and fish processors can improve their processes is through the introduction of UV disinfection systems. Hanovia in the UK (a subsidiary of Halma Plc) is well known for its systems and has introduced them to companies all over the UK and Europe for disinfection applications.
One of the obvious big advantages of systems such as these is that they eliminate the use of strong chemicals which could contaminate or taint products. The system is always on, giving reliable operation with very little maintenance – typically, the UV lamps only need replacing once a year. There are automatic internal wipers to keep the UV lamps clean, so that there is an optimum UV output throughout the period of use.
“The system is always on, giving reliable operation with very little maintenance.”
Hanovia UV disinfection systems are compact and can be easily incorporated into a number of meat processing applications, including treatment of wash water, brine chillers, meat marinade and pickle injectors and also for disinfecting wastewater for reuse in processing.
By using the system to disinfect the water used to rinse carcasses and to wash process equipment and work surfaces, contamination can be decreased with an increase in shelf life.
The use of UV systems on recirculating brine chillers and meat pickle and marinade injectors can be extremely effective at destroying harmful bacteria such as Listeria and E. coli. UV systems can also be configured to operate effectively through a wide range of temperatures and applications, from super-cooled brines to very hot sanitation cycles.
The use of UV disinfection can also dramatically reduce water use by processing plants because it can be reused. The reuse of disinfected wastewater in applications such as chillers and cooling towers means that more fresh water can be used in washing and processing.
UV is electromagnetic radiation (light) in an energy band between visible light and X-rays. The portion of the UV spectrum between 185 and 400nm is known as UV-C and can be used as a bactericide; the best wavelength for this is 265nm. UV kills microorganisms by penetrating cell membranes and damaging the DNA, making them unable to reproduce and therefore killing them.
The UV lamp is usually housed in a quartz sleeve, which keeps the lamp dry and also allows the full UV spectrum to enter the water passing through the system. The lamp is usually mounted in a stainless steel processing chamber and the system can usually be used to treat a range of liquids, including viscous sugar-containing syrups, drinks (beer, soft drinks or water) and process water.
Loch Fyne Oysters in Scotland uses two Hanovia medium-pressure UV disinfection systems to treat depuration water on the oyster farm in the oyster and mussel depuration tanks.
“The use of UV systems can be extremely effective at destroying harmful bacteria such as Listeria and E. coli.”
The lamps, installed by Barr and Wray, can treat up to 150m³ of water per hour and have led to a 99.99% reduction in E. coli. No chemicals need to be used and the pH of the water is not affected.
The system also has an automatic wiper fitted over the quartz sleeve which surrounds the UV lamp to prevent the build-up of deposits, ensuring maximum levels of UV irradiation.
The system also uses a photon control panel displaying flow rate, UV dose and intensity. This data can be logged for up to one year and also be downloaded if required.
The Silver Spring Mineral Water Company in Folkestone uses seven Hanovia UV water disinfection systems on its bottling lines to help ensure its products are free from microbial contamination. Heinz in the UK also uses a Hanovia UV disinfection system to disinfect process water obtained from its own private bore hole.
Pennine Foods in South Yorkshire has also installed two Hanovia UV systems so that it can disinfect water used for wash down of equipment. The systems can disinfect 7m³ per hour.