Written by Larry Chmielewski, General Manager – Tray Lines & Key Accounts
Next time you walk through a supermarket, pay attention to the various types of packaging used to contain and preserve different types of food product. The packaging method depends on the product being preserved and the type of packaging being used.
One very common method to contain and preserve food product is by using rigid, non-flexible trays. Another method is to vacuum package product in flexible film and/or inject an inert gas like nitrogen to preserve the product. The one thing in common with all these techniques is the process by which the packages are produced. That process is called Horizontal Form Fill Seal (HFFS).
Horizontal Form Fill Seal (HFFS) Packaging
There are several types of HFFS systems ranging from a preformed tray sealer to horizontal flow wrap and horizontal thermoform. The package to be filled travels horizontally by means of a conveyance system. As the empty packages travel, they are filled with product in what is called a loading area.
Often, a human performs the loading of the empty product container. The higher the packaging production rate, the more humans needed in the loading area. This process has been going on for decades…for as long as the technology has existed.
Challenges Associated with Manual Tray Filling
Companies that utilize manual labor for tray filling face several challenges including:
- Workplace environmental conditions
- Repetitive motion injuries
- Food safety concerns
- Higher hourly wages
These can all impact the overall profitability of the products produced.
Moreover, the faster that a human is expected to fill a package by weight, the greater the product giveaway will likely be per package. This is because underweight packages are “not” legally allowed. This puts even more pressure on profitability. While the cost of the giveaway varies, it is typically not recoverable. When this happens, companies often begin looking for alternative methods to fully automate their product weighing and filling equipment.
Automatic Weighing and Filling Machines
Yamato was arguably the first to introduce multihead combination weighing scales. This technology was introduced to the world back in the late 1970s. Multihead weighers were designed for the specific purpose of improving weight accuracy and speed for packaging. Users of all types of packaging began to work this technology into their food-packaging operations. Today, as much as two thirds of the food that is packaged for the supermarkets is weighed and then dispensed into automatic and semiautomatic packaging machinery.
One multihead weigher could fill as many as four HFFS packages simultaneously, in patterns of 1×4 across, or 4×1 in a single file. However, many companies using HFFS could not utilize an automatic multihead weigher because their packaging process required multiple packages to be filled in arrays such as 2×2, 3×3, or 4×4 patterns.
Combination scales are not designed to package pattern arrays like this. To solve that problem, Yamato Corporation introduced the Yamato MultiPoint Depositor (MPD). Yamato introduced this patented technology over 10 years ago.
The Yamato Multi-Point Depositor (MPD) Tray Filler
The MPD was designed to collect the weighed product that is discharged by a combination scale into a matching array of compartments positioned right above the empty cavities of the HFFS system. When the MPD has the full amount of product to fill the arrays, it releases them into the tray cavities all at once. Watch the video below to learn more about the Yamato MPD.
Automatic weigh and fill systems using a Yamato combination scale and the Yamato MPD are compatible with a wide variety of food products such as IQF vegetables, IQF proteins, IQF bakery, fresh cut vegetables (not salad), salty snacks, fruit snacks, confections, and more.
At Yamato Corporation, our rule of thumb is, “If the product can be weighed using a multihead weigher, Yamato can deposit the product into a tray.”
Automatic Tray Filling for Salads
While the MPD system is highly versatile to work with a wide variety of food products, its design is not compatible with salad packaging. Salad packed in clear trays is increasing rapidly and is filling more shelf space inside supermarkets. Today, most of these trays are still packaged by hand.
There are many differences between the types of products described above and leafy green salad products that are packaged in clear, rigid, plastic trays. Piece size of leafy greens are typically much larger, meaning the bulk density is low compared to the products described above, resulting in much larger packaging containers being required compared to most other food products.
Most notable, leafy greens need to be compressed into the package in order to be suitable for automatic seal or closure of the tray. To automate filling leafy greens into trays, Yamato developed the Automatic Diving Funnel (ADF).
The Yamato Automatic Diving Funnel (ADF) Tray Filler
The Yamato ADF tray filler was designed to fill and gently tamp leafy greens into trays. This includes cut and washed leaves and/or leaves grown via Controlled Environment Agriculture (CEA) that are not washed. CEA leafy green products are typically harvested at various stages of growth: baby, teen, and adult. All types are different yet have one similar characteristic – they are vulnerable to damage from over-aggressive compression into the tray after filling. The aftereffects of this damage are not seen until days after packaging, meaning the damages are first seen by the consumer when the product is on store shelves. The overall net effect is reduction in shelf life.
A benefit to companies that automate with Yamato equipment is that the ADF system utilizes a unique concept not used by any other tray filler called, “ratio filling.” Rather than filling a tray with the entire product target weight and compressing the product into the tray like a trash compactor, the Yamato ADF fills in two stages.
Typically, the ratio filling is set up with a split 50% (fill number one) and 50% (fill number two) into the tray, but other ratios can be programmed as well depending on the product and the packaging requirements. This ratio filling results in a lighter compression needed to make the leafy greens fit into the tray. Lighter compression means less or no damage and higher-quality product on the shelf resulting in the best possible products for consumption.
To learn even more about the Yamato ADF, watch the video below.
Benefits with Automatic Tray Filling
Whether a company is using a Yamato MPD or Yamato ADF tray filler for their products, the benefits are the same. These benefits include:
There is no human involvement in the weighing or filling of the HFFS package. In some higher output lines, this can mean the company reduces their manual labor by as many as 16 to 18 people.
Improved Weight Accuracy
Yamato tray-filling solutions deliver zero underweights and can reduce giveaway by 7% to 15%. This equipment works in tandem with Yamato multihead weighers. These combination scales are designed with Yamato’s patented, heavy-duty load cells that offer industry-leading accuracy.
Increased Production Output
Yamato automatic tray fillers can increase your production output by as much as 50% compared to manual-fill lines. This equipment provides much faster filling speeds, meaning more filled trays.
Improved Food Safety
The Yamato automatic tray-filling solutions take human hands out of the equation. Ask any food safety inspector what they think about automating a manual packaging process. Products are ultimately being packaged in a much more hygienic environment.
Lastly, while there is significant capital investment to replace a manual-fill HFFS package line, the payback for this investment is typically within a 12-to-18-month period. This means that the user is significantly increasing their profitability in a fairly short period of time.
Let’s Automate Your Tray Filling Together
Want to know more, or still not sure which of our machines are right for you? Please contact us. The weighing and filling experts at Yamato would be happy to help you reduce your manual labor and design a more profitable packaging operation for you.