Applications — Food Processing

A food plant is not one application; it is thirty, each with its own surface, soil, frequency and rule. This page works through them — what the task is, how solution is applied, what decides the set point, and how the task is verified. Two rules apply to all of them: clean first, because soil consumes available chlorine, and where a task requires registered label claims, use a registered product such as HOCl-AS200 per its label.

Zone 1 — food-contact surfaces

Belts, tables, slicers, dicers, fillers, hoppers, moulds, tools, bins and utensils. These are cleaned with detergent and mechanical action, rinsed, then sanitised. Hypochlorous acid is applied by spray, foam or wipe after cleaning, kept wet for the contact time in the SOP, and drained or air dried as the procedure requires.

Food-contact sanitising is regulated. 21 CFR 178.1010 permits hypochlorite sanitising solutions at up to 200 ppm available chlorine, used followed by adequate draining, and your food safety plan decides how that applies to each surface. Published work on food-contact materials includes neutral electrolyzed water for sanitising cutting boards and neutral electrolyzed water on stainless steel against E. coli O157:H7, Salmonella Typhimurium and Listeria monocytogenes.

Zone 2 — adjacent surfaces

Equipment frames, guards, control panels, chutes, carts, racks, pallet trucks and the underside of everything. These carry no product but they feed zone 1 through hands, tools and splash. Application is spray, foam or wipe after cleaning, usually at the same or a slightly higher set point than zone 1, with ATP verification on a rotating schedule.

Zone 3 — the processing environment

Floors, walls, drains, floor–wall junctions, forklifts, doors, hose stations and footbaths. Soil loads are heavier and biofilm is more likely, so this zone is usually specified at a higher strength, applied by flood, foam or low-pressure spray, always with mechanical action on the drains and junctions that matter.

• Drains. Brush and clean first; treat drains last in the sequence and never with the tools used on food-contact surfaces. Dedicated, colour-coded equipment is the norm.
• Footbaths and boot washes. Solution becomes contaminated quickly; replace on a schedule and check strength, not just appearance.
• Hose stations. Drops fed from a holding tank make the correct solution the easy option. Label every station with the contents and the set point.

Zone 4 — remote areas

Corridors, welfare areas, locker rooms, canteens, warehouses and offices. Routine surface work at a lower frequency, useful mainly because it reduces what walks back into the plant.

Cold stores, chillers and condensate

Cool, wet and rarely dry: the conditions Listeria and spoilage flora prefer. Evaporator coils, drip trays, condensate drains, door frames, floors and racking need a scheduled clean-and-sanitise with attention to the parts that stay wet. Plan for defrost windows, and verify with environmental swabs rather than appearance.

Conveyors and continuous lines

Belt surfaces, splices, rollers, return paths and scrapers. During breaks and at end of shift, belts are cleaned and then sanitised; in some plants a low-volume spray bar applies solution to the return path during production, where the rules and product allow. Hollow rollers and splices are classic harbourage — treat them as a maintenance problem, not a chemistry one.

Fogging, misting and electrostatic spraying

For large halls, cold stores and complex equipment, solution can be applied as a fine mist or charged spray with equipment such as the Jet H2, ByoPlanet sprayers or a nebulizer. Follow the product label for the method and area, and your own risk assessment for ventilation and re-entry. Fogging is a supplement to cleaning, never a substitute for it.

CIP circuits

Some plants use hypochlorous acid as the sanitising step in a CIP circuit, after the detergent and rinse phases. Treat it as a change to a validated process: check material compatibility through the circuit, confirm that the strength at the far end of the loop is what the SOP specifies, revalidate, and update the CIP records. Temperature, flow and contact time all belong in the validation.

Process water, flumes and ice

Where hypochlorous acid is dosed into water that contacts food, the applicable authorisation governs it. EcoloxTech customers can rely on FCN 1811 for process water or ice contacting meat, poultry, seafood, fruits and vegetables and shell eggs, at free available chlorine not exceeding 60 ppm, with a drain step or potable rinse for product consumed raw. Produce washing under 21 CFR 173.315 carries a rinse requirement instead. Dosing needs monitoring and records; the regulations page has the citations.

Building the task list

Every implementation starts with one document: a list of sanitation tasks. For each task, record the area and zone, the surface, the current product and concentration, the method, the contact time, the frequency, the volume used and who does it. It is dull work and it is the difference between a system that fits the plant and a machine in a corner.

The list then sorts into three groups: tasks that move to generated solution, tasks that stay on a registered product because the claim must be documented, and tasks that are really cleaning problems and need a detergent or a mechanical fix rather than a different sanitiser. Most plants find the third group larger than expected.

A worked zone schedule

Methods compared

What decides the set point

With onsite generation, strength is a setting rather than a product choice, so the question becomes what each task needs. The inputs are your food safety plan, the applicable regulatory limit, the soil load, the contact time available and the surface. Heavier soil, drains and biofilm-prone areas are usually specified higher than routine surface work; anything that contacts food is governed by the applicable rules. Whatever the number, verify it at the point of use: strength falls in storage and on contact with soil.

Where it does not belong

• As a cleaner. No detergency; it is the step after cleaning.
• In dry processing areas as routine practice, where introducing moisture raises risk.
• Mixed with anything. Never with acids, ammonia or other cleaning chemicals.
• Where a label claim is required and only a registered product will satisfy it.

Tools, colour coding and traffic

The best solution in the plant is still delivered by a brush, a cloth or a hose, and those are as capable of moving an organism as of removing one. Keep tools zone-specific and colour-coded, store them clean, dry and off the floor, and replace them on a schedule rather than when they fall apart. Drain tools never touch anything else. Cloths that sit in a bucket of solution all shift are not a sanitising system; they are a transport system. The same logic applies to people: define the traffic routes and changeover rules, because a correct procedure executed in the wrong order still moves contamination from zone 3 to zone 1.

Frequently asked questions