Piston fillers are a great option for packaging liquids. They offer fast and accurate fill rates, versatility with the ability to handle many different types of products, and they're gentle on products. They're ideal for viscous liquids including batters, sauces, pastes, icing, chunky fillings, and certain aerated products. Generally, these liquid packing machines are used to fill liquids that are squeezed through pastry bags or similar packaging.