UV Disinfection of Sugar Syrup
How Does Ultraviolet Work?
Ultraviolet energy causes permanent inactivation of micro-organisms by disrupting DNA so that they are no longer able to maintain metabolism or reproduce. The maximum effectiveness occurs at between 240nm and 280nm, with the most effective wavelength typically at 254nm. The Sukrut lamps produces this wavelength in narrow spectrum in abundance as compared to other lamps.
All bacteria, spores, viruses and protozoa (including Cryptosporidium and Giardia oocysts) are permanently inactivated by UV. Concentrated Syrups, typically at 25 to 67 Brix, have a high osmotic pressure. This prevents micro-organisms growing and reproducing, however they will survive in spore form and will grow once the syrup is diluted into the food product or beverage. Microbial growth in foods and beverages can cause food discolouration, off flavours and shorten shelf life. Threat of contamination has been further increased as manufacturers respond to consumer demand for reduction in chemical additives and preservatives. Manufacturing specifications are demanding and the use of UV ensures that they can be comfortably achieved, without the complexity and expense of plate heat exchangers. A high output Lamp array provides a powerful, yet controllable disinfection force.
Why is UV treatment required
- No micro-organisms survive UV disinfection
- Treatment is effectively monitored
- Permanent accurate treatment records
- In-line treatment
- UV is the most cost effective method of syrup disinfection
- Pasteurisation is expensive in capital equipment and running costs
- Sterile filtration does not remove all spores from syrup
No Detrimental Effects
- UV has no effect on pH, colour, flavour and aroma
- UV has no detrimental effect on product stability
- No steam or hot water required
Liquid Syrup In-line
The Sukrut UV LBX series are designed to eliminate organisms which are responsible for taste and flavour problems in sugar solutions. Each chamber contains Spektrotherm HP lamps, which emit a powerful germicidal dose of UV. A monitor constantly checks the UV intensity. This system is installed in-line after the storage tank discharge point, so the syrup is treated prior to dilution into the food or beverage. The syrup is treated prior to the addition of additives, flavourings or colourants, all of which reduce UV Transmission.
Modern hot dissolving systems can leave the headspace above the syrup as an ideal growing environment for spoilage organisms. Condensation containing spores and even growing cultures, can drip off the inner wall of the vessel leading to surface growth and infection of the syrup. The Sukrut UV product range is designed to overcome his problem. The UV works in the headspace to prevent airborne contamination, it can be fully immersed in the syrup when the vessel is filled to capacity.
Selection of the appropriate UV model for each application should be decided in conjunction with a Sukrut UV specialist, who will also advise on the installation and dose.