CIP (Clean In Place) vs. COP (Clean Out of Place)

What Is CIP?

CIP stands for Clean In Place. It means cleaning food-contact surfaces without opening up the equipment, by circulating, spraying, and flowing cleaning solutions and clean water in sequence through pipes, vessels, and pumps.

The U.S. 3-A Sanitary Standards (3-A SSI) definition, in essence: the equipment stays in its production position and is cleaned by circulating, spraying, or flowing chemical solutions and water rinses to remove soil from food-contact surfaces. Parts of the equipment unsuitable for CIP are removed and cleaned by COP or by hand.

A typical CIP sequence is: pre-rinse → alkaline wash → intermediate rinse → (if needed) acid wash → rinse → sanitize → final rinse. Temperature, concentration, flow rate, and time must all be controlled and recorded.

Advantages of CIP:

• No disassembly, so cleaning time is short and labor requirements low.
• Cleaning conditions are the same every time, making automation and record-keeping easy.
• Staff don't have to handle chemicals, so it's safer.

What Is COP?

COP stands for Clean Out of Place, meaning "removed for cleaning." The 3-A definition, in essence: after the equipment is partially or fully disassembled, soil is removed in a wash tank using circulating chemical solutions and water rinses, and the tank may be fitted with a circulation pump. There's also "manual cleaning": likewise after disassembly, but done by hand with brushes, non-woven pads, scrapers, and hoses.

Common COP equipment includes parts washers and wash tanks; see Cleaning Equipment: Parts Washers and Crate Washers for details.

Is CIP Suitable for Encrusting Machines?

Generally, encrusting and forming machines rely mainly on COP and manual cleaning, for several reasons:

1. The product is a sticky solid: Dough, red bean paste, and meat filling aren't liquids; residue lodges in corners of the hopper, screw, and nozzle, and circulating cleaning solution has a hard time carrying it away.
2. The structure has many moving parts: Screws, cutting mechanisms, and dies have gaps between parts that can only be seen and cleaned once taken apart.
3. Visual inspection is needed: Only after removal can you see whether parts are clean, worn, or damaged.

That's why the design of encrusting machines focuses on parts being "easy to remove and easy to wash." By contrast, piping and vessel systems for liquid products such as dairy, beverages, and sauces are well suited to CIP.

Both may coexist in one food factory: the sauce tanks and piping for preparing fillings use CIP, while the encrusting machine uses COP.

Where Might CIP Be Used in an Encrusting Plant?

The encrusting machine itself is mainly disassembled for cleaning, but the same factory may still have equipment suited to CIP:

• Preparation tanks and transfer piping for sauces, syrups, and liquid fillings: Liquids flow through closed piping, suitable for circulation cleaning.
• Closed vessels for cooking or blanching.
• Some models of large filling mixers: Some are designed with spray balls or nozzles, allowing a CIP pre-wash before key parts are removed and cleaned by hand.

To do CIP, the equipment must be designed for it from the start: piping must drain completely with no dead spots, pumps and valves must suit circulation cleaning, and there must be a system to control temperature, concentration, flow rate, and time. Existing equipment can't necessarily be converted to CIP directly.

The Hygienic Design Perspective

The European Hygienic Engineering & Design Group (EHEDG) and the U.S. 3-A SSI both promote "hygienic design" of food equipment, so the equipment itself is easy to clean:

• Food-contact surfaces are smooth, with no dead spots or crevices.
• No water pooling; surfaces drain on their own.
• Parts can be removed and installed without special tools.
• Materials withstand detergents and sanitizers.

3-A standards cover designs ranging from manual cleaning with "a bucket and brush" to full CIP; CIP isn't the only thing that counts as hygienic. In Taiwan, Article 7 of the Standards for Food Factory Construction and Equipment (食品工廠建築及設備設廠標準) also requires food machinery to be easy to clean, disinfect, and inspect; Annex 2 of the Regulations on Good Hygiene Practice for Food (食品良好衛生規範準則) requires food-contact surfaces to be smooth and free of dents or cracks.

How to Judge Cleanability When Choosing Equipment

• Ask the maker to demonstrate disassembly and reassembly, and time it.
• Check whether parts have dead spots and whether welds are smooth.
• Ask which parts can be washed with water and which detergents can be used.
• Ask whether matching parts washers or washing baskets are available.

FAQ

Q: What is CIP?
A: Clean in place: cleaning without disassembling the equipment, by circulating cleaning solution through pipes and vessels; mostly used for piping systems for liquid products.

Q: What is COP?
A: Clean out of place: removing parts and washing them in a wash tank or washer.

Q: Can encrusting machines use CIP?
A: Encrusting machines handle sticky solids and have many parts, so they generally rely on COP and manual cleaning, with parts removed for washing and visual inspection.

Q: Is CIP more hygienic?
A: Not necessarily. Hygiene depends on equipment design and whether cleaning is done properly; manual cleaning or COP done well is just as hygienic.