Energy & Power, Heating, Cooling & Drying

How spiral vibratory technology is improving a difficult food processing process

Phil Black - PII Editor 13/03/2014

122 1 minute read

Listen to this article

Revtech has received the California Almond Board proof of process for a 5 log reduction on microbial populations and the total elimination of entero-bacteria such as E. Coli, Listeria and Salmonella.

Using unique patented spiral vibratory technology, Revtech’s units pasteurise, toast & roast grains, cereals, seeds or nuts. Decontamination is achieved using the Joule effect, comprising a combination of dry radiant heat with a steam cycle to sterilise the product. Gently handling food as it under goes treatment, Revtech processes nuts such as Brazils, Almonds and Walnuts without chipping or damage to their final appearance.

This certification follows the installation of units around the world for the pasteurising or toasting & roasting of Almonds, Cashew nuts, Sesame and Pumpkin seeds respectively. Most recently, a unit has been installed in Australia to pasteurise almonds, processing 7 tonnes of product per hour with a validated 5 log reduction in microbial growth from an Australian lab. There is also a validation protocol available from Campden BRI.

Not using steam to heat during the first stage of the cycle ensures that the essential oils of the raw foodstuff are not stripped, reducing the risk of rancidity, and that its moisture content is controlled. Only once the product is at temperature does the steam cycle of the process begin, allowing the natural defences of nuts and seeds to be preserved, thus retaining an extended shelf life. Homogenous treatment of foodstuffs is integral to the process, with the option to toast & roast dry ingredients to EBC levels as high as 1500 without the risk of fire. Crucially, the product is discharged cool and ready for immediate packing after being processed, which minimises the risk of recontamination or spoilage.

Requiring only small amounts of steam means that the process ensures excellent preservation of organoleptic properties and, as it operates at atmospheric pressure, no visible difference between treated and untreated product. Very low power consumption per ton processed bring additional cost benefits, as the machine also has a reduced cleaning time of 1 hour, negligible maintenance costs and requires only one operator to run an entire unit.