Challenge

Framptons produces oat milk and other plant-based drinks from its factory in Shepton Mallet, Somerset. The company identified an opportunity for improvement to prevent some batches of oat milk appearing too diluted. "When we were transitioning between tanks, we could end up with small slugs of water left in the line," explains Project Engineering Manager Steve Turner. "It was difficult for the operators to always ensure that the lines were purged correctly." As laboratory testing was not frequent enough to be of use in production, a real-time sensor was needed to ensure consistency of the suspended solids from batch to batch.

Solution

Endress+Hauser proposed the OUSBT66 near-infrared (NIR) inline suspended solids sensor connected with a Liquiline CM44P field transmitter. The sensor provides reliable and precise measured values in real time to optimise processes and product yield. Its hygienic design is CIP/SIP-resistant and allows autoclavation. A demonstration of the sensor in Framptons’ laboratory clearly identified a shift in absorption between the diluted samples and neat samples, after which a site trial from February 2024 to the end of April 2024 produced good results. Being offered a trial was reassuring for Framptons, as Steve Turner explains: "We’ve used a different brand in the past and we weren’t very successful with it, so we were a bit dubious about spending the money. But Endress+Hauser were kind enough to let us trial a unit, so that was definitely a plus."

After the trial Framptons immediately purchased one measurement loop, with the potential for more in future. If the solids sensor identifies a watery product based on a product-specific limit, it is automatically diverted away from the finished product tank and returned to the pasteuriser. "The operator can see on the screen if it’s diverted and why – for a concentration reason, temperature or anything else," says Steve Turner. "It’s really straightforward and simple to maintain as the sensor is also cleaned during routine CIP."

Benefits

As well as improving product quality, using the sensor has resulted in significant cost savings for Framptons of around £100,000 per year, far outweighing the initial purchase. This is down to less water being used for rinsing and less product being diverted away from the finished product tank. As Steve Turner says, "Before we installed the sensor we were routinely letting the product travel over 150 metres back to the pasteuriser. Now the operators are using it to switch over to the product tank a lot earlier, so we’re not losing product."

The real-time monitoring and adjustment of the water/product mixture has improved product consistency, without the need for time-consuming offline sampling. All the data produced is fully accessible and traceable for compliance requirements.

After the success of the first unit, plans have progressed to install the instrumentation on other product lines. The experience of working with Endress+Hauser has so far been positive and stress-free. "It’s a good brand, and there’s always someone there to help us," confirms Steve Turner. "We’ve never had an issue."