Rubber is one of the most versatile and useful tools in food and restaurant settings. It is used in gaskets, seals and o-rings, and works in a variety of ways. Some of these restaurant rubber products work to seal stored goods while others help move food items from one place to another. Rubber seals are essential to grocery stores, restaurants and food processors.
However, not just any materials will do. In addition to serving their specific functions, these rubber seals also need to avoid altering the taste or purity of any food or liquid they touch. The issue is not just a practical concern, it is a legal one.
FDA-Grade Rubber
The Food and Drug Administration (FDA) regulates food handling as well as any additives used in their production. The rubber seals used in food production fall under the “indirect food additives” category. The applicable FDA regulation (21 CFR 177.2600) lists certain ingredients as Generally Recognized as Safe (GRAS) and specifies the maximum amounts of any elements that will come into contact with a food or beverage.
You also need to store these o-rings away from non-food-grade o-rings. The lubrication used on those o-rings also needs to meet FDA standards. Sanitary guidelines will need to be followed as well.
Material Considerations
Certain substances like edible oils or milk need special considerations. The wrong o-ring ingredients can discolor these items. Various elastomers can also be vulnerable, and certain chemicals, including the chemicals in some food products, will erode the o-rings, causing you to lose a true seal and endangering the quality of your ingredients.
Managing Extreme Hot and Cold Circumstances
The temperature should be another consideration. For this variable, you will need to consider the temperature within the system as well as the specific temperature experienced at the site of the o-ring. Sometimes they can be substantially different. Further, you have to look at the length of exposure. Some materials are better at handling short bursts of extreme temperatures while others do better when levels are sustained over a more extended period.
Appliances Used Day After Day
Appliances and devices that receive frequent use are going to have different rubber sealing needs than devices that are rarely used. Breakout friction includes intermittent part movement; high pressures can develop that cause the seal to adhere to the internal wall and ultimately tear, making the seal fail. Any seal you pick needs to be able to handle this specific type of friction.
Likewise, running friction requires its own separate type of rubber seal. In this case, parts move continuously, generating heat as a result. As the o-ring gets hot, it swells, generating more heat in turn. Ultimately, there is seal extrusion, then it fails. The right o-ring, like one made from fluorocarbon rubber, can largely prevent this from happening.
In other words, the whole thing can be very confusing and tricky to navigate. You will need to look at the materials used, any FDA certifications the products hold, the materials being handled and the conditions in which the o-ring will be applied.
