What to consider when you’re looking for an alternative to gamma
We regularly have food manufacturers who contact us looking to solve a contamination problem they’ve solved before — Salmonella on spices, larvae in imported produce, elevated microbial loads on ingredients, etc.
Most typically, they’ve solved it in the past with gamma. Gamma works, but it isn’t the only cold-treatment option, and it’s often hard for producers to find gamma that is available on short notice for a reasonable price.
Electron beam (E-Beam) irradiation achieves the same outcomes as gamma — pathogen reduction, disinfestation, shelf-life extension — using a fundamentally different source. Instead of photons emitted by a radioactive isotope, E-Beam uses a stream of high-energy electrons produced by a machine called a particle accelerator. That single difference has practical consequences worth understanding (Compare: Gamma vs. E-Beam).
Speed and Supply Security
A gamma processing cycle is typically measured in hours, because the dose rate from a Cobalt-60 source is comparatively low when compared to an accelerator-based process like E-Beam.
E-Beam delivers the required dose in seconds. The accelerator switches on and off like any other piece of equipment, so there’s no radioactive inventory to manage, no decaying source to replenish, and no exposure to the Co-60 supply chain. For high-throughput product, the economics and the logistics often favor E-Beam decisively.
The Trade-Off: Penetration
Electrons don’t travel as far through matter as gamma photons do. How deep they reach depends on their energy — food applications are capped at 10 MeV — and, critically, on the density and dimensions of the packaged product. Gamma’s deep, near-uniform penetration lets it treat dense, bulky totes with little fuss. E-Beam treats most properly configured cases and cartons beautifully, but the dose it deposits varies with depth in a way that typically must be characterized rather than assumed.
That is where dose mapping comes in.
What Dose Mapping Is, and When You Need It
Every irradiation process must deliver results within two limits at once: a minimum dose high enough to achieve your sanitary or phytosanitary goal, and a maximum dose low enough to preserve product quality and stay within regulatory limits. The ratio between the highest and lowest dose anywhere in the package — the dose uniformity ratio, or DUR — tells us whether both limits can be met in a single pass.
To establish that, we place dosimeters throughout a representative package, run it through the beam, and build a three-dimensional picture of exactly where the dose lands highest and lowest. The resulting map confirms that the cold spot is still receiving a lethal dose and the hot spot isn’t being over-treated.
Depending on product type, your specific requirements, and the dimensions of the finished package, this step ranges from a quick confirmation to a more involved study — and for some products, it isn’t needed at all. At NextBeam we help our customers weigh the considerations that inform which path to take (Read: Depth-Dose Curves and Understanding E-Beam Penetration).
Talk To Us Before You Assume Gamma is the Answer
The fastest way to find out whether E-Beam fits your product is a short conversation. Tell us:
- What you’re treating and what the contamination is
- What you’re trying to achieve — a specific log reduction, a quarantine/phytosanitary requirement, a shelf-life target
- The packaging, mass, and interior layout you’re working with, and your throughput
From there we can usually tell you quickly whether your product is a straightforward fit, whether it needs dose mapping first, and what throughput and cost look like.
Gamma may have been the default for a long time. For a growing share of products, E-Beam does the same job faster, cleaner, and at better economics — and we can help you find out whether yours is one of them.
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