On an industrial slicing line, what happens immediately after the cut is just as important as the cut itself. For products such as sliced cold cuts, the Interleaver system inserts a sheet between the slices, making them easier to separate and more convenient for the end user to eat once the package is opened.
Without an Interleaver, when the package is opened, the slices could stick together and break when you try to separate them, making the product less convenient to eat. To prevent this and adapt the product’s presentation to packaging requirements, FINOVA machinery can incorporate two distinct systems: the Interleaver and the Underleaver.
Both are optional modules that can be integrated into the line depending on the product type, packaging format, and process requirements.
What is an interleaver system?
The Interleaver is a sheet-insertion system: it automatically inserts a sheet of paper or plastic between slices to prevent them from sticking together and to make them easier to separate once the package is opened. This improves product handling and provides greater convenience for the end consumer. Depending on the slicer model, the Interleaver can be configured with up to 3 lanes, allowing for the interleaving of multiple product lines in parallel. At FINOVA, we offer two Interleaver variants, both designed to make sliced products easier to consume: the paper or plastic Interleaver, the traditional system, and the Interleaver SprayFil, a more recent spray-based alternative.
Paper or Plastic Interleaver: Features
- It automatically places a sheet of paper or plastic between slices.
- Prevents the slices from sticking together when consuming products arranged in stacked or staggered patterns in different types of packaging.
- It improves the package’s appearance and makes it easier to use.
- Particularly well-suited for serving sliced cured meats or cheeses.
This is the most common system used in sausage and cheese slicing lines, where the individual separation of each slice is a key requirement for the end user’s use and consumption.
SprayFil Interleaver: Features
- An alternative to the traditional method of placing paper or plastic sheets between slices of cold cuts.
- Apply a thin layer of spray between the slices instead of using a physical separator.
- It reduces sticking between the individual slices without the need for paper or plastic separators.
- It provides efficient and more environmentally friendly separation by eliminating the use of interlayer material.
- Suitable for various types of cold cuts or cheeses.
SprayFil is the option to consider when the goal is to reduce the consumption of consumables on the production line without compromising the spacing between slices of sausage. You can learn more about how both variants work in our article on interleaver systems for sausages and cheeses, or consult the technical data sheet for FINOVA’s Interleaver module.
What is an Underleaver system, and how does it differ from an Interleaver?
The Underleaver solves a different problem: it is a separate module from the machine, designed for portioned meat products or sliced sausages for the Horeca sector. Instead of separating each piece individually, it places a sheet of paper or plastic under the portion to serve as a support base for that final stage of the process before packaging, ensuring optimal final consumption.
Unlike the Interleaver—which is integrated as a standalone module into slicers—the Underleaver operates on a single lane, and thanks to its design as a standalone module, it can be integrated into different models of slicers, as well as other machines and production lines dedicated to the finishing of meat products prior to packaging, such as cutters, formers, etc.
Features of the Underleaver System
- It automatically places a sheet of paper or plastic under the entire portion, which is already prepared for packaging.
- It facilitates the handling, transport, and subsequent packaging of the piece or portion.
- It helps maintain the shape and appearance of the meat product in its final form.
- A standalone module that can be integrated into various cutting systems and is compatible with a wide variety of meat cuts.
Interleaver vs. Underleaver: Which One Should You Choose Based on Your Product?
The choice between one system or the other depends on what stage of the process you’re in and what product you’re working on:
| Interleaver | Underleaver | |
| Function | Separate each slice of cold cuts individually | Separate portions from the package |
| Lanes | Up to 3, depending on the slicer model | 1 lane |
| Variants | Paper/plastic or SprayFil system (spray) | Paper or plastic? |
| Traditional product | Cured meats or sliced cheeses that must be separated one by one | Meat cuts, portions, or slices of cold cuts for the hospitality industry |
| Integration | Additional module for the slicer, integrated into the cutting process itself | Add-on module for slicers or other meat-processing machines |
In practice, many sausage slicing lines—such as those that use the SliceFil-420 modular slicer—include the Interleaver as one of the modules that can be configured before the machine is manufactured, whereas the Underleaver is offered as a separate module for the final finishing stage of meat products, just before they move on to a packaging machine or thermoformer.
Simplified Cleaning and Maintenance
Both the Interleaver and the Underleaver are designed to facilitate cleaning and sanitation of the production line, a particularly critical aspect in the food industry. Their design allows for quick and easy assembly and disassembly, which facilitates access to the various components and reduces the time spent on cleaning between batches or at the end of each production shift.
This ease of disassembly is no minor detail: in plants that process sliced cold cuts or meat cuts in the finishing stage—as is the case with the SliceFil-300 ham slicer—reducing tool-free cleaning time directly translates into more line time available for production and easier compliance with standard hygiene protocols in the meat industry.
Frequently Asked Questions About Interleaver and Underleaver
What is an interleaver in a slicer?
This system is designed for slicing cold cuts; it automatically places a sheet of paper, plastic, or a layer of sprayed liquid (SprayFil) between each slice, preventing them from sticking together and making it easier to separate them individually.
What is an Underleaver used for?
The Underleaver is a separate module attached to the machine, designed for the finishing stage of meat products: it places a support sheet under the entire piece of meat once it is ready for packaging, without separating the slices from one another.
Does the Interleaver SprayFil completely replace paper or plastic interleaving sheets?
Yes, SprayFil applies a thin layer of liquid spray instead of a physical separator, eliminating the need for paper or plastic and reducing the consumption of consumables on the filling line.
Are the Interleaver and Underleaver modules easy to clean?
Yes, both modules are designed for quick, tool-free assembly and disassembly, which simplifies cleaning and sanitation tasks between production batches.
Interleaver, underleaver, or both in your slicing line?
These systems are not mutually exclusive: a single line can combine an Interleaver to separate the slices of cold cuts and, in the final stage of the process, an Underleaver as a separate module to support the meat product before packaging. The correct configuration depends on the product, the sales format, and the stage of the process at which each solution is needed.
If your plant needs to automate the slicing of sausages or the finishing of meat products before packaging,contact FINOVA’s technical team, and we’ll help you determine which module—or combination of modules—best suits your production line.
