Taking guard of milk processing

An automated technology that detects processing losses in dairy plants could have the potential to save the industry millions of dollars a year and help prevent pollutants from entering waterways.

The technology was developed by Lincoln Agritech Ltd and has been commercialised by Christchurch-based start-up company CertusBio.

Known as Milk-Guard, the automated biosensor device is suitable for continuous monitoring in commercial operating conditions. It uses a lactose-specific enzyme to measure the percentage of dairy products present in waste streams and processing lines.

These percentages are automatically sent to a dairy plant process control room, where operators can monitor them and make changes to the production process if necessary.

CertusBio CEO Dr Matthew Jones said that due to the vast quantity of dairy products processed in New Zealand, large amounts of valuable products could be lost quickly.

“Dairy plant operators will be able to improve the resource and energy efficiency of their plant processes by reducing losses of valuable dairy products and ultimately increasing company profitability.”

Dr Jones said current loss-monitoring methods were reliant on retrospective testing collected over 24 hours.

“Because this testing is done after the dairy products have been processed, it doesn’t allow for adjustments to be made while the plant is operating, so losses can’t be limited in real time.”

Two to three per cent of all dairy products are lost during processing, and while this is inevitable to a certain extent, a significant proportion of losses could be avoided.

“The estimated total loss for an average dairy industry processing line is $6.5 million per year,” Dr Jones said.

“This also contributes to the level of pollutants caused by the dairy processing industry, as dairy plant wastewater has a number of characteristics that require careful management, including influent pH swings of 2–13, high fat loads and variable incoming organic and nutrient loads. Variations occur both on a seasonal and daily basis.”

Trials at dairy processing plants have demonstrated Milk-Guard’s ability to frequently detect product losses during processing, which could be worth in excess of NZ$30,000 for a single event.

In addition to wastewater monitoring to reduce processing losses, the Milk-Guard device can be used to account for all material entering and leaving a processing plant, liquid transfers within a plant and segregating raw materials containing high-value products.

The combination of these uses is expected to provide a significant return on investment for dairy processors.