Hampshire-based JenAct has developed a pulsed light system to create the new machine along with US firm Xenon Corporation. The project aims to tap into the fact that mushrooms are relatively unique in being capable of having their vitamin D content artificially enhanced.
100g of sun-grown mushrooms contain around 10 per cent of the recommended daily allowance (RDA) of vitamin D, but JenAct says almost all commercially grown mushrooms contain only about one to two per cent of RDA. However, by exposing them to UV light this can be increased to more than 200 per cent.
Xenon had been working on a system for enhancing vitamin D levels in mushrooms, and although successful was only suitable for use in laboratories. Based on the process approved by the FDA and the EU, JenAct has further developed the technology for the food production environment.
Xenon's pulsed lamps, which generate the high intensity UV light, can achieve the desired Vitamin D levels in fresh mushrooms within a few seconds. However, the pulsed UV systems must be carefully controlled and well integrated into the machine otherwise they can pose significant health and safety risks.
To achieve the correct UV dose for the mushrooms, it was necessary to ensure that a defined UV light energy was applied to every punnet. This required careful design of the UV treatment zone to ensure that uniform UV light reached the final irradiated product while reducing light leakage to almost zero.