Quite often when I'm discussing a new pump with a customer, I hear some variation of the following concern: "I've heard that impeller pumps will beat up my wine". There's a lot to unpack in this phrase, so let's get down to it. What's In an Impeller? The first consideration here is what is meant by "impeller pump". This, I think, is where the confusion starts. Both Flexible Impeller pumps and Centrifugal Pumps are often called "impeller pumps" because they use an impeller to convert the rotation of a motor into energy that pushes liquid forward. Beyond that similarity, they are very different. While many facilities—particularly breweries—use centrifugal impeller pumps, they are typically avoided for wine transfer, except in cases where budget is a big concern (impeller pumps are relatively cheap), or some shear isn't expected to have any perceptible effect on the final product. Flexible Impeller pumps, on the