Key Considerations When Filling Jars

When packaging liquids, both bottles and jars are a popular choice across industries such as food and beverage, cosmetics, household products and pharmaceuticals, among others. While the process of filling jars and bottles may be seen as very similar, there do exist a few key differences to consider when choosing liquid filling machines and other packaging equipment for jars.

Container Openings

Jars typically have a wider mouth or opening than those found on bottles. While this makes it easier to fill certain products, such as sauces, jams, it may also require modification to what might be thought of as standard filling machine components. A jar filler machine may use nozzles with a larger opening, allowing particulates to pass through with ease. The larger nozzles can also speed up the filling process for thicker products and add protection against air pockets that may form when filling a higher viscosity liquid.

Filling Principles

The three most common filling principles for liquids include filling by volume, filling by net weight, and filling to a level. While any of these principles could be used for a jar filling machine, the level fill created by an overflow filling machine would be a challenge when filling wide-mouthed containers. The overflow filler uses special nozzles that seal over a bottle opening and allow product to overflow out of the container back into a reservoir. Not only would filling jars in this manner require a large diameter seal, but the head space in certain jars may not allow the room for liquid to reach the overflow port of the nozzle. Furthermore, large seals would need more space on manifold, limiting the number of fill heads available on a machine. While volumetric and net weight fills are common on jar filling machines, the inefficiency of the overflow principle for filling wide mouth containers means filling to a level will rarely, if ever, be seen by those using jars.

Diving Heads and Bottom Up Fills

While this feature can be used for bottles or jars, diving fill heads and bottom up fills may be seen more often when using a jar filling machine. As the fill cycle begins, heads will dive into jars, near the bottom of the container. As the product enters the jar, the heads will retract to the starting position as they continue to dispense product. This process can minimize air pockets that may occur with thicker products, while also improving product settlement for thicker, high viscosity products. Bottom up fills are not a requirement for any filler, but often the products and process will make this option beneficial to those using jars in their packaging process.

While both jars and bottles hold a variety of liquid products offered to consumers, for packagers, understanding the differences in filling equipment for jars will help to get the best equipment for the packaging process as a whole. At Liquid Packaging Solutions, we specialize in designing equipment to meet the specific needs of the container, product, and the packaging process as a whole. Contact us today to learn more about the best equipment for rinsing, filling, capping, and more!