Gently Does It

When a UK-based manufacturer of dairy-based ingredients identified a possible contamination issue related to its existing positive displacement (PD) pump, it quickly set out to find a solution.

Eddy Smeaton, a food sector specialist at Watson- Marlow Fluid Technology Group (WMFTG), takes up the story: “Our customer had a number of PD pumps on site, and although they performed well and were food-grade rated, there was always the worry of potential contamination from the wear parts of the pump. As a result, the company started looking for a pump that could do the same job, but which could take away the risk.”

By chance WMFTG was already talking to the company about a separate dosing pump application, so it was already aware of the features of the MasoSine Certa pump. It ticks all the boxes when it comes to suitability for use in hygienic applications, meeting the requirements of 3-A design, EHEDG Type EL – Class I and even EHEDG Type EL – Class I Aseptic. The aseptic certification confirms the bacteria-tight design when using a double mechanical seal. In addition, it proves that the pump can be steam sterilised. WMFTG provided the company with a trial pump so that it could assess its suitability for transferring soft cultured products.

Further, unlike traditional pumps, with rotors that cut through the fluid, the sinusoidal rotor of the MasoSine Certa gently carries product through the pump to reduce shear – an important factor when handling dairy-based products. Further advantages delivered by sinusoidal technology include energy efficiency. It can cut power consumption by up to 50% when used with high-viscosity fluids. Importantly for this application, separation between the wet end and dry end ensures that there is no potential for contamination.

The customer has since expanded one of its facilities with the introduction of a new filling machine, for which another Certa pump has been specified, bringing the total number of units in the facility to 10. Each is used for transferring different soft cultured products such as yoghurt, butter, cream and soft cheese. It moves them either from intermediate bulk containers (IBCs) to plant or from tanks to plant, or pushes them through pasteurisers. The pumps are also used for blending ingredients in various viscosities. In terms of transfer distance, the farthest is 20 metres with a four metre head. Flow rate tends to be dictated by other parts of the process.

A German dairy, Goldsteig Käsereien Bayerwald, also put its trust into the MasoSine Certa Sine pump for the production of cream cheese because gentle handling was a key requirement for transferring the cream used by the dairy to produce mascarpone and whey for ricotta.

“Pumping is an important stage of production, where due care and gentle handling matter most,” said Günter Schlattl, operations manager at Goldsteig. “If the shearing forces are too high, then the binding – and thus the structure of the mixture – can be damaged. Ultimately, the final quality of the cream cheese will suffer, and for ricotta and mascarpone, the texture of the endproduct is essential.” Another critical consideration when choosing a pump for this application related to the need for regular clean-inplace (CIP) operations. “The appropriate certification was crucial for the application as we perform a daily CIP clean with caustic,” said Günter. “After one of our first CIP operations following installation, we opened the pump to check the results and found that it was totally clean.”

Another advocate of Certa pumps in the dairy sector is A E Rodda & Son which has been producing Cornish clotted cream since 1890.

In 2012, the company installed a MasoSine SPS 200 sine pump as part of a new clotted cream line, and its performance impressed the maintenance team.

“We were in the process of investing in a new depositing machine, which essentially deposits cream into a pot and seals it with a lid, so we needed to look for a suitable hygienically-designed pump to transfer the product from mobile storage tanks,” explains Paul Johnson, maintenance supervisor at Rodda’s

“Over six years of hard work we had virtually no maintenance issues with an existing MasoSine SPS 200 which has looked after itself. Importantly, the pump does not damage or compromise product integrity, which is crucial to our production process.”

The same approach was needed for the company’s new pouring cream production facility – low shear, low pulsation and gentle handling. “Using a centrifugal pump, for example, would effectively churn the cream into something like butter,” said Paul. “A sine pump was the way forward and we were keen on the new Certa from WMFTG, especially because of its energy-efficiency attributes.”

WMFTG’s technical team advised A E Rodda & Son that the smallest pump in the Certa range, the Certa 100, would meet the application requirement as it was able to deliver the required flow rate of up to 4,200 l/hr.

In terms of the process, a mobile storage tank is wheeled up to the new depositing machine, and the pump transfers cream from one to the other. The pump is mounted low, facilitating a two meter head into the machine’s hopper. No priming is required.

“We have had the MasoSine Certa 100 for around 12 months now and there have been no issues whatsoever,” concluded Paul. “From experience we have now also learned that it is three times more expensive to run a pneumatic pump than an electric pump.”