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It might sound too basic to be true but water bubbles are being touted as a way of killing microbes on fresh produce without the same need for potentially harmful chemical disinfectants.

At five free antimicrobial workshops in England and Scotland chemical engineer Dean Burfoot of AHDB Horticulture will tell fruit and veg growers that fine bubble technology has the potential to reduce the volume of microbes found on fresh produce.

Adding tiny bubbles to water causes a natural scrubbing action as they move around, producing atoms known as free radicals, which act as cleaners.

Importantly, it is hoped that the technology, which has been used in Japan for a number of years, could also reduce the levels of disinfectants used in the washing process.

There is now a need for growers to ensure that levels of chlorate and percholate on fresh produce are kept to a minimum following the introduction of maximum residue levels by the European Commission in November 2015.

Horticulture growers in Scotland have been making concerted efforts to ensure their produce is free of contaminants that could damage human health. But this often involves using disinfectants called biocides to kill off microorganisms in irrigation and produce wash waters, and to disinfect equipment and surfaces.

Biocides kill bacteria such as E. coli 0517 before produce is sold, however chlorine-based biocides can lead to chemical compounds known as chlorate or perchlorate being left on produce.

Burfoot said: “Bubble technology has been used in Japan for a number of years and is just beginning to catch on here. Washing surfaces or produce using water with fine bubbles destroys 90 per cent more microorganisms than using water alone.

“Creating bubbles in water can also disinfect the water itself as the agitation produces free radicals which act as cleaners. The technology has also been seen to improve plant growth and this is thought to be due to increasing the oxygen and nitrogen content of the water.”

According to the AHDB, fine bubble technology is relatively cheap and growers can purchase specially designed nozzles and combine them with existing kit to aerate their water supply.

Grace Choto, AHDB research and knowledge exchange manager, said: “The ‘Keep it Clean’ Microbials workshops around the UK will provide growers with novel methods and guidelines to help ensure that produce is free from microbial contaminants.”

The workshops will be held in five locations around the UK, including Fife (15-16 February), Bolton (21 February), Claverdon (1 March), Maidstone (7 March) and Taunton (21 March).Growers can register to attend through theAHDB website.