✅ Other Dairy Matrices Sample Analysis

While the Delvotest® range of products is validated primarily for use with raw milk, there are instances where testing other dairy matrices—such as milk powders, creams, and whey—may be necessary. These products differ from raw milk in various physical and chemical properties, which can affect the performance of microbial inhibition tests like Delvotest® T with the Delvotest® Accelerator Smart.

Complication

Testing other dairy matrices presents several challenges:

• Absence of Defined Maximum Residue Limits (MRLs)
   Unlike raw milk, processed milk products lack established MRLs due to variability in processing methods and product concentrations. This makes it difficult to standardize testing thresholds for antibiotic residues in these products.
   
• Variability in Physical and Chemical Properties
  Other dairy matrices may have different concentrations, solids content, or pH levels compared to raw liquid milk. For example, milk powders (after reconstitution) can be more concentrated, and alkaline whey has a higher pH. These differences can influence the performance. 

Resolution

To address these challenges and ensure accurate testing, follow these steps:

• Follow IDF guidelines for sample preparation
   Document FIL-IDF B-471 Detection of Inhibitors and Antimicrobial Residues in Milk and Dairy Products by Screening Methods—Guidance on Preparation of the Test Portion provides detailed instructions on how to prepare different dairy matrices for testing, ensuring compatibility with microbial inhibition tests. It can be accessed via the following links:
   
   https://www.fil-idf.org/wp-content/uploads/woocommerce_uploads/2014/03/B471-2014Inhibitors-and-antimicrobial-residues-in-milk-and-milk-products.CAT_-rts6zg.pdf
   
   https://shop.fil-idf.org/collections/publications/products/detection-of-inhibitors-and-antimicrobial-residues-in-milk-and-dairy-products-by-screening-methods-guidance-on-preparation-of-the-test-portion