PasLite
The PasLite test is an internationally accepted method used by dairies and food manufacturers to verify HTST pasteurization for many types of dairy products, including fluid white milk, flavored dairy, non-flavored dairy, and solid/semi-solid dairy (like cottage cheese and sour cream) that are regulated by mU/L or kg measurement*.
The PasLite test verifies the completeness of milk pasteurization by detecting alkaline phosphatase, a natural enzyme in milk that is destroyed by heat and hold time of pasteurization. The test takes 3 minutes and multiple samples can be run simultaneously.
When a dairy sample is mixed with PasLite reagents and incubated, the resulting solution emits light in an amount directly proportional to the phosphatase enzyme present. The novaLUM II-X system is used to measure the light emitted and coverts light readings to enzyme units. Phosphatase readings greater than 350 mU/L indicate product pasteurization issues according to US and EU pasteurization requirements.
The PasLite test limit of detection for liquid dairy products is 20 milliunits per liter (mU/L) phosphatase (approximately 0.002% raw milk). This is well below the 350 mU/L level (0.1% raw milk) required by most public health agencies.
Benefits
- Limit of detection below public health guidelines
- ISO and IDF standardized method (ISO 22160 /IDF 209)
- Approved by the US NCIMS, New Zealand NZFSA, and Victoria (Australia) VDIA
- Results in 3 minutes
- Tests liquid, semi-solid, and solid dairy products
- Easily incorporated into an HACCP program
- Results can be read on the novaLUM II-X system
Regulatory Info
- Approved by US National Conference on Interstate Milk Shipments (NCIMS)
- Approved by the New Zealand Food Safety Authority (NZFSA)
- Approved by the Tasmanian Dairy Industry Authority (TDIA), Australia
- US cheese phosphatase limits are defined in the code of regulations in µg/kg phenol units. Therefore, cheese screening with these methods in mU/kg is not recommended without presumptive positive confirmation by the ug/kg phenol methods.
Industries
The PasLite test is easily read on:
- AOAC article, “Evaluation of a Chemiluminescence Method for Measuring Alkaline Phosphatase Activity in Whole Milk”
- International Dairy Federation (www.fil-idf.org), ISO 22160|IDF 209:2007, “Milk and milk-based drinks – Determination of alkaline phosphatase activity – Enzymatic photo-activated system (EPAS) method”
- International Dairy Federation (www.fil-idf.org), Bulletin of the IDF No. 435/2009, “Standardization of a Chemiluminescent Method to Detect Alkaline Phosphatase in Liquid Dairy Products”