How Products Were Selected:
Products were selected to represent those popular among readers of ConsumerLab.com and commonly available nationally in the U.S. ConsumerLab.com purchased products on the open market through retail stores, on-line retailers, and direct sales companies. Products were not accepted directly from manufacturers.Testing Methods:
- Size, color and visible mold utilizing United States standards for grades of shelled walnuts.
- Microbial contamination: Analysis of microbial contaminants using the FDA's Bacteriological Analytical Manual (BAM) and AOAC methodologies with application to USP <2023> for E. coli, Salmonella, Listeria, B. cereus, yeast and mold.
- Aflatoxins: Aflatoxin B1, B2, G1 and G2 utilizing High Performance Liquid Chromatography — Mass Spectroscopy (HPLC-MS).
- Hexanal by Gas Chromatograph with Flame Ionization detection (GC-FID).
- Heavy metals: Analyses for lead, cadmium and arsenic utilizing Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS).
ConsumerLab.com may modify or use other appropriate test methods if necessary to test special product formulations.
Identities of products were not disclosed to laboratories performing the testing.
Passing Score:*
To be "Approved" by ConsumerLab.com, a product must meet the following requirements:- Size, color and visible mold utilizing United States standards for grades of shelled walnuts.
- Color: No more than 10% of kernels shall be darker than amber (Per USDA Standard for No. 1 grade Shelled Walnuts — 2017).
- Size:
- When labeled as "halves" must consist of 85 percent or more, by weight, half kernels, and the remainder three-fourths half kernels (tolerance 5% may be smaller).
- When labeled as "pieces and halves" must consist of 20 percent or more, by weight, half kernels, and the remainder portions of kernels that cannot pass through a sieve with 24/64 inch round openings. When a exceeds this minimum requirement, the actual percentage of halves may be specified (tolerance 18% may be smaller).
- When labeled as "pieces" must consist of portions of kernels that cannot pass through a sieve with 24/64 inch round openings (tolerance 25% may be smaller).
- When labeled "small pieces" must consist of portions of kernels that pass through a sieve with 24/64 inch round openings, but that cannot pass through a sieve with 8/64 inch round openings (tolerance 12% may be smaller).
- Visible mold: No more than 5% of kernals may display visible mold. (Per USDA Standard for No. 1 grade Shelled Walnuts — 2017).
- Aflatoxins: Total aflatoxins B1, B2, G1 and G2 must be no more than 10 ppb (EFSA).
- Hexanal: No maximum set, but values greater than 2 mcg/g will be noted, as this may indicate less than ideal storage conditions (Limit proposed in Mexis, Food Control 2009).
- Microbes: Test negative (<10 cfu/g — limit of quantification) for Escherichia coli, B. cereus. Non detectable for Listeria and Salmonella spp. Values for total combined yeasts and molds exceeding 1,000 cfu/g (USP <2023> 2023) will be noted, but this is a passing criterion.
- Heavy Metals: Products must not exceed the following limits:
Lead:- Products marketed for use by children may not exceed the State of California's Prop 65 limits for lead in dietary supplements of 0.5 mcg per recommended daily serving with an additional allowance of 0.8 mcg if the product contains more than 1,000 mg/day of calcium.
- Products with a single serving weights of less than 5 grams which are not marketed for use by children, may not exceed the State of California's Prop 65 limits for lead in dietary supplements of 0.5 mcg per recommended daily serving (above which a warning regarding reproductive harm, birth defects, or cancer risks is required in California) with an additional allowance of 0.4 mcg if containing 250-999 mg/day of any combination of elemental calcium, magnesium and potassium, 0.8 mcg if containing 1000 mg/day of any combination of these minerals. An additional allowance of 0.5 mcg is provided if containing 250-999 mg/day of whole herb (not extract) ingredient or 1.0 mcg for products containing 1000 mg/day or more of whole herb (not extract). However, total lead allowance will not exceed 2 mcg per daily serving.
- Products with single serving weights of 5 grams or more which are not marketed for children may not exceed 2.5 mcg per serving nor 4.0 mcg per daily serving.
- If marketed for use by children, may not exceed 3.0 micrograms of cadmium per recommended daily serving (based on Canada's limit for a child weighing 75 lbs.). If not marketed for use by children, may not exceed 4.1 micrograms of cadmium per recommended daily serving (above which California's Prop 65 law requires a "reproductive harm" warning due to developmental toxicity and male reproductive harm).
- Contain less than 10 micrograms of total arsenic per daily serving (based on Canada’s limit per daily serving of a natural health product, and U.S. EPA and state of New Jersey limit in 1 liter of water). Products found to exceed this amount were tested for inorganic arsenic and must not contain more than 2.1 micrograms of inorganic arsenic per daily serving (Canada's additional limit in natural health products).
- May not exceed 2 micrograms of inorganic mercury per daily serving (based on EPA limit for mercury in 1 liter of water).
- Be in compliance with FDA labeling requirements.
* Passing scores allow for specific margins of technical error associated with each analysis. ConsumerLab.com reserves the right to disqualify a product at any time from passing its testing if it considers such product to display unacceptable variation in quality, present a safety risk or to provide misleading or inaccurate information in its labeling.
