Raw milk testing and identifying sources of heat-resistant Psychrotrophic bacteria
QualiTru raw milk quality testing systems provide accurate sampling for the identification of raw milk contaminates. The ability to identify and isolate bacteria, including heat-resistant bacteria is vital to safe and efficient operations for milk processors. Using QualiTru septa and handling devices allows for effective quality control and quality assurance to ensure superior product production.
The growth of heat-resistant psychrotrophs results in product defects in 18-21 days.
To determine the presence and effect heat-resistant bacteria would have on dairy product quality, QualiTru suggests the following procedures:
- Using the QualiTru 2 Liter Composite Bag and Aseptic Sampler, aseptically obtain a 2L sample of product at the High Temperature Short Time (pasteurizer).
- Incubate the bag for 18-24 days (2 days beyond code) at 45ºF.
- Conduct a Standard Plate Count.
- Identify the bacteria using gram-staining procedures for any counts greater than 1,000,000/ml (gram positive bacteria will indicate heat-resistant psychrotrophs).