That’s a Tricky Question…
A question we are frequently asked by our customers is “Can I use a metal hose for food-related applications?” It’s a simple question, but the answer isn’t always so simple.
The quick answer is no, metal hose generally cannot be used for the transfer of food-grade materials. This has nothing to do with the capabilities of the manufacturer or the quality of materials used in the hose. On the contrary, while the steel used may indeed be “food-grade,” the corrugations in the hose can potentially trap food media and make it difficult to clean the hose to the proper standard. Instead, you typically see PTFE hoses in these types of applications. The only exception to this would be if the media is at a temperature high enough to kill off any bacteria, which may allow for a metal hose to be used in some cases.
However, just because metal hose generally cannot be used to transfer food-grade materials does not mean that there are not applications for metal hose elsewhere in production! You just have to know where to look for them…
Metal Hose for Food Industry Applications
Clean in Place Systems
A key component of food production that requires the use of metal hose is clean-in-place (CIP) systems. Clean-in-place systems serve as a way to clean and sanitize the internal surface of a piping system as part of the routine cleaning of the production line or when production is being changed over to a different product. These systems utilize steam and chemicals (such as sodium hydroxide) to clean the piping system, which can be hard on any non-metal hoses that are used in the system. Instead, non-metal hoses are removed to be cleaned separately and metal hoses are installed in their place during the cleaning process. These metal hoses are better suited to handle the high heat and caustic cleaning solution running through the system, making metal hose an optimal solution for this application.
Steam Jacketed Hoses
A special type of metal hose assembly that is often used in food industry applications is jacketed hose. Jacketed hoses are comprised of two parts: an internal hose conveying the primary media and an external channel conveying the secondary media used to raise (or lower) the primary media’s temperature. For applications in the food industry, the secondary media is often steam. These hoses are used to transfer food products that would otherwise be too thick to flow freely or may harden inside the hose, causing the line to clog. The steam transferred through the exterior hose heats up the primary media, making it less viscous and easier to flow through the piping system.
Now, you’re probably thinking- But wait, didn’t you say that metal hose generally can’t be used for transferring food-grade materials? Yes, that’s true. Corrugated metal hose is generally not recommended for the transfer of food-grade product. However, using metal hose in this application is acceptable as long as the product will be further processed or pasteurized later down the line, eliminating any bacteria present. Prior to this point, it may be possible to utilize a metal hose.
Gas Appliance Connectors
One final type of metal hose that’s used in food applications is gas appliance connectors. These are widely used in restaurants and commercial kitchens to connect gas lines to gas-fueled appliances, such as a stove or grill. Along with being fire-safe, using metal in this application provides a more rugged solution, as the hoses are cycled frequently when the appliances to which they are connected are moved daily for routine cleaning.
What About My Application?
There are plenty of applications for metal hose in the food industry if you just know where to look for them. Do you have a potential food-related hose application and are unsure if you can use metal? Let us know and we’d be happy to help!
The original article was written by Abby Svitana, Market Analyst at Hose Master.
For more information about using metal hose in food applications, contact Gallagher Fluid Seals today.