Ultra-Clean for half the price
Sterivent filter technique now available in laminar-flow version
A study conducted by the Tara dairy in Israel has found that ultra-clean production lines on the basis of a recently developed innovative filter technique for ripening and buffer tanks can extend the shelf life of products by 30 per cent to 100 per cent. Emmi in Switzerland and Adams in Greece have adopted the system.
Based on the same concept, the supplier has now built a laminar-flow filter for filling machines. Fischer Planning from Israel has introduced the Sterivent system several years ago. This air purifier, in a stainless steel housing, consist of a prefilter, a blower and a sterile filter (Hepa) and has been developed specially for dairies. The concept is oriented to installation techniques as well as to the microbiological conditions in processing environments. Construction volume, investments and operating costs with a filtering grade of 97.997% were dramatically minimized as compared to standard filters.
UC up to the filling machine
The combination of Sterivent and Laminar flow allows for building an Ultra Clean (UC) line with the installation of Sterivent on incubation and storage tanks and of Laminar flow on filling machines. The Sterivent provides sterile air for incubation and storage tanks also during cleaning. The laminar-flow variants are installed in filling machines. This closes a much ignored hygienic breach: for cleaning, staff uses normally water hoses, spraying wetting altogether machines and filtration system. This disables the function of a normal Hepa-filter and turns it instead into an incubator and a source of germs. But also inside the installation is the threat of contamination. For instance, when package breaks during the packing process and product is spraying against the filter material. The laminar-flow principle, according to Fischer Planning, is hermetically sealed to stand those challenges from inside and outside. The air flow was designed by the German-Israeli engineering company in a way that in fact no whirl flow zones exist. Therefore the whole process is surrounded by sterile air. Manufactures benefit from economical advantages. Thanks to such UC lines, there is no need for expensive sterile tanks.
Field tests
When Tara built a new factory near a much travelled highway in Israel, they were worried about fine dust and soot particles emitted by passing vehicles. They decided for a field test to examine the effects of Sterivent and a laminar-flow filter on milk, cheese and yoghurt. They installed a total of 20 filter systems in different product lines and compared the newly achieved sterility with conventional prolonged from six to twelve days, cottage cheese from eleven to 16 days, cream cheese and soft cheese from 18 to 26 days, soya milk products from 30 to 60 days. Tara registered yet four additional advantages of the Sterivent concept:
-high availability of sterile air
-no heating of the sterile air was necessary
-lower cost of changing filter elements
-economic and low-cost installation.
Up to eight tanks connected to a single filter
Emmi have recently mounted the Fischer system on buffer storage tanks before filling machines. The Fischer technique produces sterility for up to eight tanks. Emmi: We have connected four tanks which are standing outside; to a common Sterivent and up to now we are completely satisfied as far as the results are concerned. In another case, in one of the halls, one filter is connected to six storage tanks. Without this development we would have had to rebuild completely, because the room would not have permitted to reequip the machines conventionally.
European Dairy Magazine 2/EDM
Dairy & Fluid Foods Technology/ March 2006
Written by
Bernd Genath
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