• Aflatoxin control is critical; implement robust lot testing and participate in the Almond Board of California’s PEC program to ensure compliance with stringent EU regulations on aflatoxins.
• A validated microbial lethality step before milling is essential to mitigate pathogen risks, aligning with FDA’s preventive controls framework under 21 CFR Part 117.
• Allergen management requires dedicated processing lines and validated cleaning protocols, utilizing NIST RM 8404 for reliable allergen measurement and compliance verification.
• Maintain low water activity (ideally 0.25–0.35) and moisture levels (≤6%) during storage to prevent rancidity and ensure quality, supported by cool storage conditions (2–7°C) and high-barrier packaging.

Food Safety & Quality Standards

Product: Almond Flour

Section: Regulatory & Compliance

Almond Flour Food Safety & Quality Standards

Executive summary

Almond flour sits at the intersection of low water activity, high-lipid foods and major allergen controls. In my assessment, the highest-impact levers for ensuring both safety and quality are:

1. Aflatoxin hazard control at the farm and procurement stage, reinforced by strong lot testing and, where applicable, participation in the Almond Board of California’s Pre-Export Checks (PEC) program;
2. A validated microbial lethality step on almonds prior to milling (consistent with 21 CFR Part 117’s preventive controls framework);
3. Rigorous allergen cross-contact prevention in facilities handling multiple allergens;
4. Control of water activity, oxygen exposure, and temperature throughout storage and distribution to suppress microbial growth and minimize rancidity and off-flavors; and
5. Method verification using traceable reference materials such as NIST RM 8404 Almond Flour to harmonize and benchmark allergen measurement performance.

Together, these measures align with current good manufacturing practice (CGMP), hazard analysis, and risk-based preventive controls (HARPC) expectations and deliver the strongest return on risk reduction per unit effort for almond flour manufacturers and users in 2025 (FDA, 2025; Almond Board of California, 2022; Phillips et al., 2022).

Regulatory foundation: 21 CFR Part 117

• CGMP and preventive controls. 21 CFR Part 117 requires facilities to maintain CGMP and implement hazard analysis and risk-based preventive controls that address biological, chemical (including aflatoxins and allergens), and physical hazards reasonably likely to occur. For almond flour, key provisions include: raw materials either not containing injurious microorganisms or being pasteurized/treated; compliance with FDA regulations for aflatoxin and other natural toxins in susceptible ingredients; preventing allergen cross-contact during processing and packaging; and maintaining safe moisture levels in foods that rely on water activity control (e.g., nuts and dry mixes) (FDA, 2025).

• Allergen cross-contact. CGMP explicitly requires that batters, sauces, dressings, and similar preparations used repeatedly be protected against allergen cross-contact and that filling, assembly, and packaging operations protect food against allergen cross-contact and contamination. Translating this to almond flour: dedicated lines, validated cleaning, visual inspection plus rapid allergen swabs, and label control are central to compliance and consumer safety (FDA, 2025).

• Water activity and moisture control. FDA requires foods that rely on water activity control to be processed to and maintained at a safe moisture level. Almond flour, like nuts and dry mixes, is stabilized by low water activity; maintaining that state through the supply chain is a regulatory and quality imperative (FDA, 2025).

Aflatoxin hazard and export assurance

• Aflatoxin susceptibility. Almonds and almond-derived ingredients are susceptible to aflatoxins. 21 CFR Part 117 requires susceptible raw materials to comply with FDA limits prior to use, placing a due-diligence obligation on suppliers and manufacturers to conduct representative sampling, validated testing, and supplier verification (FDA, 2025).

• Almond Board of California PEC program (EU-facing). The PEC program is an industry-run, regulator-recognized pre-export verification system to control aflatoxins in almonds exported to the EU, where aflatoxin limits are among the most stringent globally. The current program manual (v11.1, 2022) defines lot formation, sampling, accredited laboratory testing, and documentation requirements. While PEC primarily covers kernel shipments, manufacturers of almond flour exporting to the EU benefit from aligning upstream lots with PEC verification and maintaining chain-of-custody of compliant lots into milling and finished goods documentation (Almond Board of California, 2022).

Analytical reliability for allergen measurement

• NIST RM 8404 Almond Flour. NIST developed RM 8404 specifically to harmonize measurements of allergenic almond proteins in foods. The value-assigned material is supported by interlaboratory comparison and collaborating laboratory data analysis to provide traceability and allow laboratories and manufacturers to benchmark and validate method performance (e.g., ELISA, LC-MS) across matrices. In my view, integrating RM 8404 into internal verification (e.g., quarterly check standards, recovery studies) reduces method drift risk and supports regulator and customer confidence in allergen control programs (Phillips et al., 2022).

• Programmatic context. NIST’s Food Safety program highlights a portfolio of allergen-related reference materials and QAPs to underpin accurate, comparable measurements, which are crucial for label verification, cross-contact investigations, and regulatory compliance across domestic and export markets (NIST, 2022).

Process safety controls from almond to flour

• Validated lethality prior to milling. A preventive control (e.g., steam pasteurization, PPO, or other validated lethality step) applied to almond kernels before milling reduces pathogen risk and aligns with 21 CFR expectations that raw materials either be free of injurious microorganisms or be treated during manufacturing. Although almonds are low-aw, some pathogens can persist; milling increases surface area and disperses any contamination, making pre-milling lethality a prudent and, in my opinion, essential control for ready-to-eat flour applications (FDA, 2025).

• Milling and hygienic zoning. Milling should be conducted in controlled environments with dust management, metal detection, and hygienic zoning that separates raw (pre-lethality) from ready-to-eat (post-lethality) areas to prevent recontamination. Allergen-only facilities or dedicated allergen lines minimize cross-contact risks.

• Enzyme use in downstream bakery applications. While not intrinsic to almond flour production, downstream bakery users often apply α-amylases. EFSA’s 2023 and 2024 opinions on α-amylases from non-GM Cellulosimicrobium funkei and Bacillus licheniformis concluded no safety concerns under intended uses in starch processing and baking, indicating that common enzyme aids do not introduce new risks when applied as directed (a relevant consideration when almond flour is blended in dough systems) (EFSA, 2023; EFSA, 2024).

Water activity, moisture, and oxidation management

• Water activity thresholds. Scientific reviews and industry summaries converge on critical water activity points: microbial growth is generally prevented below aw ≈ 0.65; lipid oxidation in almonds is minimal near aw ≈ 0.25–0.35 (approximately 3–4% moisture). Total moisture for almonds should be maintained at or below ~6% during storage. For almond flour, which increases surface area and exposes lipids, adherence to comparable or tighter moisture/aw control is advisable to limit rancidity and maintain sensory quality (Almond Board of California, 2014; Mandalari et al., 2016).

• Temperature and oxygen. Almonds are ~50% fat, predominantly unsaturated, and rich in vitamin E (α-tocopherol), which provides antioxidant protection; however, elevated temperature, oxygen exposure, and light accelerate oxidation. Recommended storage for almonds and roasted products is cool (≈ 2–7°C) with controlled RH (≈ 55–65%), protected from light and odors, and with packaging that provides strong oxygen and moisture barriers. These conditions extend to almond flour to the extent feasible, with refrigerated or frozen storage substantially slowing rancidity onset in high-surface-area flour (Blue Diamond Growers, 2019; Almond Board of California, 2014).

Structured summary of hazards and controls

Storage and shelf-life guidance for almond flour and related almond products

Analytical quality assurance for allergen control

Processing impacts on structure and implications for flour quality

Thermal processes that precede or follow milling change almond microstructure. Roasting dehydrates kernels, damages cell walls, promotes oil body coalescence, and can reduce skin polyphenols. Studies report 40.7% to 59.1% decreases in water content of roasted almonds relative to raw, driven primarily by evaporation, and Maillard reactions contribute to brown color and flavor development. For flour processors, these structural changes mean:

• (i) roasted almond flour may exhibit different oil release and oxidation kinetics;
• (ii) thermal history influences texture, flavor, and shelf-life; and
• (iii) process specifications must be tight to avoid over-roasting and accelerated rancidity.

Where “raw” sensory profiles are desired in flour, validated pasteurization that preserves native microstructure is preferred over high-intensity roasting as a lethality step (Mandalari et al., 2016).

Actionable program design: my recommended approach

• Hazard analysis and CCPs

  • Establish a CCP for aflatoxin compliance at receiving, including statistically robust sampling plans and accredited lab methods. Tie supplier approval to demonstrated historical compliance and PEC participation for EU-bound supply chains. Document lot identity through milling and finished product release (FDA, 2025; Almond Board of California, 2022).
  • Define a CCP for lethality on almonds prior to milling. Validate process parameters (temp/time/humidity or chemical) against target pathogens, including worst-case cold spots and load variability; verify routinely with biological indicators or surrogate studies as appropriate (FDA, 2025).

• Allergen management

  • Design for allergen-only lines or time-segregated campaigns; validate wet and dry cleaning for almond residues; adopt label control with barcode verification and line clearance. Use NIST RM 8404 to verify analytical methods used for cleaning validation and finished product label checks (Phillips et al., 2022).

• Environmental and hygienic design

  • Implement hygienic zoning to prevent post-lethality recontamination; control dust; apply metal detection and optical sorting where relevant; institute environmental monitoring tailored to low-aw RTE environments (FDA, 2025).

• Moisture/aw and oxidative stability

  • Set specification limits for flour aw and moisture aligned with optimal oxidation suppression (aw ≈ 0.25–0.35; moisture ≤ 6%). Use high-barrier packaging and nitrogen flushing where feasible. Maintain cool distribution temperatures (preferably 2–7°C for long storage) and protect from light and strong odors. Adopt FEFO inventory rotation and routinely trend peroxide values and sensory attributes over shelf-life (Almond Board of California, 2014; Blue Diamond Growers, 2019).

• Verification and continuous improvement

  • Calibrate allergen assays with RM 8404; run internal control charts; participate in interlab comparisons/QAPs. Review complaint data and non-conformances; periodically re-validate lethality and cleaning as equipment, throughput, or formulations change (Phillips et al., 2022; NIST, 2022).

Conclusion

Almond flour’s safety profile benefits from intrinsic low water activity but is challenged by the potential for aflatoxin carryover, persistence of low-aw-tolerant pathogens without a lethality step, and its status as a major allergen. The most reliable, regulator-aligned path to robust safety and enduring quality is to harden the supply chain through PEC-aligned aflatoxin control, implement a validated pre-milling lethality step, institutionalize best-in-class allergen management with traceable analytical verification (leveraging NIST RM 8404), and design storage-packaging systems that keep aw low, oxygen and light out, and temperatures cool. Based on the 2025 regulatory and scientific landscape, this integrated program delivers the clearest, defensible compliance posture under 21 CFR Part 117 while maximizing shelf-life and sensory integrity of almond flour across global supply chains (FDA, 2025; Almond Board of California, 2022; Phillips et al., 2022; Almond Board of California, 2014).

References

• Almond Board of California. (2014, July). Almond shelf life factors (Technical summary 2014AQ0007). Almond Board of California. https://www.almonds.org/sites/default/files/content/attachments/2014aq0007_shelf_life_factors.pdf
• Almond Board of California. (2022, August 1). Pre-Export Checks (PEC) Program Manual (Version 11.1). Almond Board of California. https://www.almonds.org/sites/default/files/2023-02/PEC%20Program%20Manual%20v.11.1.pdf
• Blue Diamond Growers. (2019, August). Almonds storage guidelines. Blue Diamond Ingredients. https://bdingredients.com/wp-content/uploads/2019/08/blue-diamond-almonds-storage-guidelines-aug19.pdf
• European Food Safety Authority (EFSA). (2023). Updated safety evaluation of the food enzyme α-amylase from the non-genetically modified Cellulosimicrobium funkei strain AE-AMT. EFSA Journal, 21(6):e08101. PubMed Central. https://pmc.ncbi.nlm.nih.gov/articles/PMC10312074/
• European Food Safety Authority (EFSA). (2024). Safety evaluation of the food enzyme α-amylase from the non-genetically modified Bacillus licheniformis strain AE-TA. EFSA Journal, 22(5):e8780. PubMed Central. https://pmc.ncbi.nlm.nih.gov/articles/PMC11094576/
• Mandalari, G., Grundy, M. M.-L., et al. (2016). A review of the impact of processing on nutrient bioaccessibility and digestion of almonds. PubMed Central (PMC). https://pmc.ncbi.nlm.nih.gov/articles/PMC5003169/
• National Institute of Standards and Technology (NIST). (2022, January 21). Value assignment of reference material 8404 almond flour for allergen detection (NIST Special Publication 260-218). NIST. https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.260-218.pdf
• National Institute of Standards and Technology (NIST). (2022). Food Safety Program overview. NIST. https://www.nist.gov/mml/csd/primary-focus-areas/food/food-safety
• U.S. Food and Drug Administration. (2025). Current Good Manufacturing Practice, Hazard Analysis, and Risk-Based Preventive Controls for Human Food (21 CFR Part 117). eCFR. https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-117

Frequently Asked Questions

What are the key food safety standards for almond flour?

Almond flour must comply with 21 CFR Part 117, which mandates maintaining current good manufacturing practices (CGMP) and implementing hazard analysis and risk-based preventive controls. Key provisions include ensuring raw materials are free from harmful microorganisms, controlling aflatoxin levels, and preventing allergen cross-contact during processing.

How does the Almond Board of California's PEC program impact almond flour safety?

The PEC program provides a pre-export verification system to control aflatoxins in almonds destined for the EU, where limits are stringent. Participation in this program helps manufacturers ensure compliance with aflatoxin regulations and enhances the safety profile of almond flour by verifying upstream lot quality.

What measures should be taken to prevent allergen cross-contact in almond flour production?

To prevent allergen cross-contact, facilities should implement dedicated production lines, validated cleaning protocols, and rigorous label control. Additionally, rapid allergen testing using methods like NIST RM 8404 can help verify compliance and ensure consumer safety.

What is the recommended moisture content for almond flour to maintain quality?

Almond flour should maintain a moisture content of 6% or lower to minimize chemical reactions and support water activity control. Keeping moisture levels low helps prevent rancidity and preserves the sensory qualities of the flour.

How does water activity affect the safety and quality of almond flour?

Water activity (aw) levels below 0.65 are critical for preventing microbial growth, while levels around 0.25–0.35 help minimize lipid oxidation. Maintaining these aw levels throughout storage and distribution is essential for ensuring the safety and quality of almond flour.

What are the implications of validated lethality steps prior to milling almonds?

Implementing a validated lethality step, such as steam pasteurization, before milling almonds reduces the risk of pathogens that may persist in low-water activity environments. This step aligns with FDA expectations and is crucial for producing safe, ready-to-eat almond flour.

How can manufacturers ensure compliance with FDA regulations regarding aflatoxins?

Manufacturers can ensure compliance by conducting representative sampling and validated testing of raw materials for aflatoxin levels, adhering to FDA limits. Establishing supplier approval processes and participating in the Almond Board of California's PEC program further strengthens compliance efforts.