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Proficiency Testing Program
Ensuring Consistency for your Laboratory
ADPIAmerican Dairy Products Institute More is your go-to partner to prove that your dairy laboratory’s tests results align with your peers in the industry. With our Proficiency Testing Program, a valuable member benefit of ADPIAmerican Dairy Products Institute More, your laboratory has access to an independent, trustworthy resource to verify the consistency of your results and to ensure you are maintaining essential competence with the analytical methods.
ADPIAmerican Dairy Products Institute More partners with Eurofins to administer the Proficiency Testing Program. We are now offering four product groups in the Program. When registering for the program, organizations may select a single category or a mix of product groups that best align with your organization’s portfolio of dairy ingredients production.
*New in 2026: The addition of Edible Lactose as a product group, and new certifications for 2026 will make the program more relevant and compliant with the requirements of your company’s QualityFocus on doing things well and producing a product acceptable to consumers More Management Systems.
ISO 17025
ISO 13528
ISO 17034*
*ISOInternational Organization for Standardization is an international nongovernmental organization made up of national standards bodies that develops and publishes a wide range of proprietary, industrial, and commercial standards. More Certification for 17034 is in progress and pending completion for the October 2026 round of testing.
Product Groups Offered in 2026
Full Range Milk Protein Concentrate (MPC)
Test Parameters:
- Protein
- Fat
- Moisture
- AshResidue that remains when milk/whey is heated to very high temperatures in a muffle oven. Organic acids are lost during ashing. Some minerals such as sulfur and phosphorous also may be lost. Other minerals may be converted to oxides, sulfates, phosphates, silicates and chlorides. In general, ash overestimates the concentration of minerals present since oxygen is combined with minerals in the remaining ash. The term often is used interchangeably with minerals and milk salts.
- Titratable Acidity
- SolubilityAbility of a liquid to dissolve another material. Examples: Lactose dissolving in water, alcohol dissolving in water. More Index
- WPN
Nonfat Dry Milk (NDM)
NDM test materials with protein content within and around the range of 34-36%, reflecting normal nonfat dry milk and/or skimmed milk powders. May contain added lactose, milk permeate, and/or milk retentate if the materials have been standardized according to international regulations.
Test Parameters:
- Protein
- Fat
- Moisture
- Ash
- Titratable Acidity
- Solubility Index
- WPN
Dairy Permeate
Dairy permeateProduced by the removal of protein and other solids from milk or whey resulting in a product with a high concentration of lactose. Removal of the dairy constituents is accomplished by physical separation techniques such as filtration and diafiltration. Also known as dairy product solids (ADPI definition). More test materials, potentially including milk permeatePortion of the milk that crosses or permeates an ultrafiltration membrane. Milk permeate contains lactose, minerals and nonprotein nitrogen. May also be known as dairy product solids. More, wheyLiquid obtained from cheese manufacture. More permeate, or both.
Test Parameters:
- Protein
- Fat
- Moisture
- Ash
- Titratable Acidity
- Solubility Index
- Lactose
NEW for 2026:
Edible Lactose
Edible lactose test materials in a 100-mesh particle size, the most common commercial variant of this important carbohydrate ingredient.
Test Parameters:
- Protein
- Fat
- Moisture
- Ash
- Titratable Acidity
- Solubility Index
- Lactose
Full Range Whey Protein Concentrate (WPC)
Test Parameters:
- Protein
- Fat
- Moisture
- Ash
- Titratable Acidity
- pH
- Lactose
Low Range Whey Protein Concentrate (WPC)
WPC test materials with protein content of approximately 34%, corresponding to WPC34 product.
Test Parameters:
- Protein
- Fat
- Moisture
- Ash
- Titratable Acidity
- pH
- Lactose
Cost of the Program (2026)
Member organizations can participate at $362 per round/$1,086 per year for each product chosen.
Samples cannot be distributed among multiple locations; multiple shipment destinations will require multiple purchases.
Timing of the Program (2026)
Participants may subscribe to one or more individual rounds, or to the entire program on an annual basis.
Round 1: May with summary reported in June
Round 2: August with summary reported in September
Round 3: October with summary reported in November
FAQ's
Yes, one set consists of 4 samples which can be distributed among multiple technicians.
Your data is coded in the summary report. Unless you share your ID information, no one will know which results are yours.
Yes, POs can be used but require a manual process on the ADPI side. Email a copy of your purchase order to Katie Blanchard kblanchard@adpi.org or to our general-purpose email address info@adpi.org.
Email Katie Blanchard kblanchard@adpi.org or our general-purpose email address info@adpi.org to obtain a quote.
Email one of the following and we will resolve your issue: Andy Powers at apowers@adpi.org, Katie Blanchard at kblanchard@adpi.org or the general ADPIAmerican Dairy Products Institute More address at info@adpi.org.
Yes, we are now accommodating international destinations as well, but with a markup to cover the additional costs of shipping. This includes any shipping destinations outside the continental U.S. Please email your purchase order or a detailed request to Katie Blanchard at kblanchard@adpi.org and we will issue a quotation which itemizes the international shipping markup.
Questions?
Andy Powers
VP of Technical Services
apowers@adpi.org | 630.530.8700 x225 (o) or 224.500.4333 (cCarbon More)
