Food-grade tanks are a common sight at breweries, dairies, and food manufacturing plants. They come in a number of sizes and capacities. For the most part, they are made from either stainless steel or cross-linked polyethylene (XLPE). Both materials have their advantages and disadvantages, so it is not appropriate to say that one is always better than the other.
For the purposes of this post, a food-grade tank is an intermediate bulk container (IBC) made to certain specifications in order to facilitate easier shipping and storage. This post will not reference the much larger storage tanks that are intended to provide permanent storage in a food processing facility.
Stainless Steel Tanks
The stainless steel food-grade tank is something that Houston-based Cedar Stone Industry manufactures. Their tanks are used frequently by breweries and dairies. Among the many advantages of stainless steel is durability. An organization looking for food-grade tanks that are capable of offering more than a decade of solid service will probably choose stainless steel over XLPE.
In a brewery, a stainless steel food-grade tank can act as a finishing tank in addition to storage. Beer is pumped into the tank where it further clarifies and gets carbonated. A little extra fermentation might also occur if that is part of the plan. One of the benefits of this setup is that the beer can be transported to another location without having to be transferred to another tank.
The biggest downside to stainless steel, as compared to XLPE, is cost. Stainless steel is many more times expensive than XLPE is. It also tends to be more porous. That means breweries and dairies need to be more careful about cleaning and sanitation.
XLPE is a specialized form of polyethylene that includes cross links for added strength. Obviously, polyethylene is a plastic. It is a pretty durable plastic used to manufacture everything from water pipes to tubing for radiant floor heating systems. It is strong enough for food storage but still flexible enough to absorb minor impacts.
A XLPE tank will not necessarily offer as many years of service as stainless steel. And though XLPE can withstand minor impact, major impact with a vehicle, steel rack, or other obstruction can significantly damage it. Manufacturers get around this flaw with their IBC totes by building them inside steel cages.
XLPE’s surface tends to be less porous than stainless steel too. Therefore, there are fewer concerns about bacteria growth. This does not mean that XLPE food grade tanks do not have to be cleaned and sanitized as diligently. They do. It is just that there are fewer worries with this particular material.
Last but not least is cost. A brand new XLPE food-grade tank will always beat stainless steel on price. For every one stainless steel tank, an organization could buy five or six XLPE tanks.
What They Are Used For
Both types of food-grade tanks are used for both storage and transport. They are ideal for liquids and semi-solids, though certain types of solids are not out of the question either. As previously mentioned, a brewery might use the tanks simultaneously for finishing and transporting beer. Dairies might temporarily store milk on premises in stainless steel tanks.
Everything from fruit juice to potable water is on the table within the commercial food and beverage sector. Elsewhere, a farmer might use XLPE or stainless steel tanks to move water around the property or to store food for animals. Used tanks that are no longer food-safe are commonly found on farms. It just shows how durable and versatile these tanks can be.