In late May of this year, Masuda, a distributor of food, energy-saving and sanitary equipment, started to sell its hybrid micro-bubble equipment named “Nanoprogress 750G” which generates ultrafine bubbles by means of mixing carbon dioxide and nitrogen into sodium hypochlorite water and is used for antiseptic washing of cut vegetables. This equipment has been already delivered to end users in the western region of Japan through industrial gas manufacturers, gas distributors and slicer manufacturers.

The equipment is characteristic in its instantaneous sterilizing effect owing to the transformation of sodium hypochlorite water of pH 8-9 (hydrogen-ion exponent) into slightly-acid liquid sodium hypochlorite of pH 6 or less in the form of ultrafine bubbles through injection of carbon dioxide and nitrogen. Furthermore, it is eco-friendly requiring no additive like hydrochloric acid, acetic acid or lactic acid.

From the viewpoint of facility, the equipment is structured to spray directly with a nozzle to the food slicing knife-blades for precut vegetables owing to generation of the ultrafine bubbles caused by mixing of 50 ppm of liquid sodium hypochlorite with 12 liter/min of water, carbon dioxide and nitrogen in the equipment attached with a CO2 gas cylinder of 30 kg, antioxidizing N2 PSA of 5 m3/h and water piping. Its gas consumption amounts to 3 to 5 liter/min of carbon dioxide and 2 to 4 liter/min of nitrogen though depending on the water quality and concentration.

President Masuda says with high expectations, “Utilization of carbon dioxide and nitrogen is an epoch-making antiseptic washing method in terms of realization of sterilization and freshness enhancement without any additive for cut vegetables. At the moment, the application of gases is limited to precut vegetables, but it is well possible to expand the application to the meat, fish, confectionery and medical fields from now on.”