Steam Pasteurized Almonds: What Buyers Should Know
Almost every almond sold in the United States has been treated to reduce Salmonella risk before it reaches a food manufacturer. Since 2007, USDA rules have required California almonds to go through a validated pasteurization step, and processors meet that requirement in one of two ways: a steam process or a chemical fumigation. Steam pasteurized almonds are treated with controlled moist heat rather than propylene oxide gas, which keeps them eligible for organic and clean-label products and free of chemical residue. The method behind a supplier’s whole almonds affects how the finished kernel can be labeled and sold, which makes it worth understanding before a product goes into development.
Why California Almonds Must Be Pasteurized
The treatment requirement traces back to two Salmonella outbreaks linked to raw almonds, one in Canada in 2001 and one in Oregon in 2004. In response, the Almond Board of California and the USDA introduced a mandatory treatment rule that took effect on September 1, 2007. Every almond grown in California and sold domestically now has to be processed in a way that achieves at least a 4-log reduction in Salmonella, meaning the treatment lowers any bacteria present by a factor of 10,000.
A few shipments fall outside the rule. Almonds sold direct to consumers at farm stands, product bound for export, and kernels shipped to manufacturers who will further process them can move without treatment, though the untreated product has to be labeled accordingly. For almost any brand buying almonds for a domestic food product, treated almonds are the standard, and the real question is which treatment the supplier uses.
Steam Pasteurization vs. PPO Fumigation
The two approved methods reach the same Salmonella reduction by very different means. Steam pasteurization applies saturated steam to the surface of the kernel for a short, controlled interval, raising the temperature enough to kill Salmonella before the almonds are dried and cooled. Propylene oxide fumigation, usually shortened to PPO, seals the almonds in a chamber and exposes them to a gas that settles on and penetrates the surface.
The practical differences matter more than the mechanics:
| Factor | Steam pasteurization | PPO fumigation |
| Treatment agent | Moist heat | Propylene oxide gas |
| Organic eligibility | Permitted | Not permitted |
| Chemical residue | None | Trace residue possible |
| Export acceptance | Broadly accepted | Restricted in several markets |
| Clean-label fit | Strong | Limited |
PPO carries a commercial drawback beyond the treatment itself. The EPA classifies propylene oxide as a probable human carcinogen, and it is prohibited in the European Union, Canada, and Mexico. A product treated with PPO cannot be certified organic and is closed off from those export markets, whereas a steam-treated kernel keeps both options open.
What Steam Treatment Means for Clean-Label and Organic Products
Steam changes the almond so little that the FDA still considers a steam-treated kernel to meet the definition of raw. A brand can pasteurize by steam and continue to sell the almond as raw or natural, which is not something a chemical fumigant allows. For clean-label positioning, where the ingredient statement is expected to read short and recognizable, the absence of any chemical treatment is a genuine advantage.
Organic products have no choice in the matter. PPO is not permitted on organic almonds, so any brand building a certified organic line needs a steam-pasteurized supply from the start. The same applies to export programs aimed at Europe or Canada, where PPO-treated product cannot enter. Choosing steam early keeps a formulation eligible for organic certification and international distribution without a disruptive supplier change later.
How Steam Pasteurization Affects Flavor and Quality
Steam pasteurization has minimal impact on the almond when the process is properly controlled. Color, flavor, and nutritional content are preserved, so the kernel blanches, slices, roasts, and grinds just as an untreated almond would, and the oil content that carries flavor into butters and pastes remains intact.
The primary concern is excess heat. When steam is applied for too long or at too high a temperature, it begins to cook the kernel, darkening the color and wrinkling the skin. Running the treatment at a validated time and temperature prevents this, achieving the required Salmonella reduction while preserving the quality of the almond.
Sourcing Steam Pasteurized Almonds
The treatment method is a sourcing decision as much as a food-safety one, because it sets what a brand can claim on the label and where the product can be sold. A supplier that runs a validated steam process, and can produce the documentation behind it, gives a brand room to pursue organic certification, clean-label positioning, and export markets without reworking its supply later.
At JSS Almonds, we supply steam-pasteurized almonds backed by BRCGS AA+ certification, one of the highest food-safety ratings in the industry, along with HACCP controls and environmental monitoring behind every lot. Our almonds come from more than 15,000 acres of California owner-partner orchards, which keeps supply steady and pricing clear of import tariffs. Because we run small minimum order quantities, a brand piloting a short run and one ordering by the pallet both draw from the same certified supply, whether the product calls for whole kernels, in-shell almonds, or a broader mix of wholesale nuts.
Building an Almond Supply You Can Count On
How an almond is treated decides more than its safety record. It sets whether the kernel can carry a raw or organic claim, clear customs into Europe, and hold a clean ingredient statement, which is why the treatment method belongs in the sourcing conversation from the beginning. JSS Almonds pairs a validated steam-pasteurized supply with the responsiveness a growing brand needs, from first sample through full production, across whole almonds, wholesale nuts, and custom nut butters. Contact our team with the product you are building, and we will match the almond, the treatment, and the documentation to where you plan to sell it.
Frequently Asked Questions
Are steam pasteurized almonds still considered raw?
Yes. The FDA considers steam pasteurization to leave the almond’s essential characteristics unchanged, so a steam-treated kernel can still be labeled and sold as raw or natural. This is not the case for almonds treated with a chemical fumigant.
What is the difference between steam pasteurization and PPO?
Steam pasteurization uses controlled moist heat to reduce Salmonella, while PPO uses propylene oxide gas. Steam leaves no chemical residue and is permitted on organic almonds. PPO is a probable human carcinogen, cannot be used on organic product, and is restricted in the European Union, Canada, and Mexico.
Do all California almonds have to be pasteurized?
Almonds grown in California and sold within the United States must be treated to achieve at least a 4-log reduction in Salmonella under a rule that took effect in 2007. Exemptions apply to direct-to-consumer sales, exports, and almonds shipped for further processing, all of which must be labeled as untreated.
Does steam pasteurization change the taste of almonds?
When the process is properly controlled, steam has little effect on flavor, color, or nutrition. Excessive steam can wrinkle and darken the kernel, which is why a validated process runs to a tested time and temperature that reduces Salmonella without cooking the almond.
Can I get organic steam pasteurized almonds?
Yes. Steam is the only treatment permitted on certified organic almonds, since propylene oxide is prohibited on organic product. A brand building an organic line needs a steam-pasteurized supply to keep its certification intact.