Gently does it when handling chocolate mixtures

12 December 2022

Selecting the best-suited pump for food applications is an important decision. The right pump can help to lower costs, reduce product waste and avoid unexpected downtime.

There are three key criteria for food and beverage manufacturers to consider:

• Product characteristics: The viscosity of different fluids can change if handled incorrectly and for materials containing solids such as fruit mixtures, the wrong type of pump can cause damage.

• Required flow rate: The higher the flow rate, the more product can be created.

• System conditions: Ensure the rest of your system is set to accommodate the pump to avoid problems and downtime.

Real-life solution

When Cémoi, a French chocolate producer, experienced damage to its chocolate and dried fruit mixture – which includes cranberries, hazelnuts, whole almonds – when it employed either a screw pump system or a diaphragm pump.

For this reason the company set out to find a better solution. Its wish list included an energy efficient pump that would ensure ingredients were not damaged in the production process while also helping it to eliminate costly downtime for maintenance or cleaning.

With the screw pump system approximately 15 to 25% of the fruit was not delivered intact into the chocolate bars. The sheared and shredded cranberries caused a build-up on the outside of the screw, leading to clogging issues and frequent production downtime. Also, dosing the ingredients was possible by adjusting the speed of the screw pump system, but this process required multiple adjustments and lacked precision.

In the first instance, Cémoi replaced the original screw pump system with a diaphragm pump but, unfortunatley, it also experienced performance issues with this pump type too, including an insufficient output and an even higher breakage rate of fragile fruit (such as hazelnuts), approximately 30% higher than with the screw pump. The rate of dried fruit damage made production impossible with this pump setup.

A transfer solution that would provide the lowest shear possible was needed. After doing some research, Cémoi changed pumps again and this time chose the SPS 300 sine pump from MasoSine with heating element from Watson-Marlow Fluid Technology Solutions (WMFTS), as it provided all the required features to handle the specifics of this application.

Sine pumps from MasoSine take inspiration from sine waves. The smooth oscillation of a sine wave informs the design of a central rotor that creates four evenly sized chambers. As the chamber rotates, it conveys the fluid from the inlet port to the outlet port. The pumping gentle action results in a smooth flow with virtually no pulsation.

The sinusoidal rotor of the SPS 300 sine pump produces a suction of up to 0.85 bar, with low shear, low pulsation and gentle handling. These characteristics are essential to ensure the safe transfer of delicate products, such as chocolate with whole dried fruit, without risking any damage.

The pumps are capable of handling soft solids up to 60mm – with hazelnuts and almonds averaging 12mm in diameter – or products with viscosities ranging from 1 centipoise (cP) to 8 million cP.

Cémoi selected a sine pump from MasoSine with a double envelope option which allows one part to be kept warm through water circulation. The process requires the pump to be maintained at a temperature ranging from 40°C to 45°C, even when not running, to ensure the chocolate remains in a fluid state.

Commenting on the solution, Pascal Lhuissier, maintenance and new works methods technician at Cémoi, said: “We selected the SPS pump based on its technology – a sinusoidal system with no mechanical parts, and a suction that does not alter the ingredients. We have not found any equivalent pump on the market that operates on this principle.

“We have reduced the breakage rate of cranberry-almond dark chocolate by three compared to the rate using a screw pump, and by four compared to a diaphragm pump (AODD). In the case of milk chocolate with hazelnuts, the breakage rate is reduced by 40% compared to a screw pump, while the diaphragm pump was not capable of transferring the product at all. The integrity of the product is maintained, and the almonds and hazelnuts, as well as the cranberries, remain whole. The appearance of the chocolate bar is improved.

“The dosing of the ingredients is also more precise. From the start of production using the screw pump, both the speed settings and the time waste were responsible for producing recyclable material. Now, thanks to the SPS pump, production starts up immediately, with virtually no loss of material.”

Considerations

As well as reducing unexpected downtime and product waste, there are other important factors that food and beverage manufacturers need to consider when selecting a pump. For example, if a pump is Clean-in-Place (CIP) compatible, workers do not have to remove the pump from the process line to clean it, which saves significant time. The MasoSine SPS has CIP and Steam-in-Place (SIP) features, and it can be disassembled in just 15 minutes. The original screw pump employed by Cémoi needed to be transported to a cleaning room using a forklift truck facility, which was time-consuming and also posed a number of safety issues.

Efficiency is also important. At a time of high energy prices, installing a pump which requires a smaller footprint saves on space on the factory floor, and energy costs.

South African Breweries (SAB), a subsidiary of multinational giant Anheuser-Busch InBev is seeing the benefits of utilising three MasoSine Certa 400 pumps for use in yeast cropping during beer production. SAB reports considerable energy savings since switching to these pumps from lobe or circumferential piston pumps.

The yeast application at SAB, with a viscosity of 2000 cP, demands power requirements from the Certa sine pump of 3.1 kW, which compares favourably to a comparable lobe or circumferential piston pump, which would typically require 6 kW.

The energy savings presented to SAB were based on the pumps running for four hours a day, seven days per week. Energy was based on a price per kWh of €0.15. The yearly (50 weeks) electricity costs for a Certa 400 sine pump can therefore be shown as €651, against €1260 for a competitor pump, giving an annual saving of €609 per pump.

Efficiency savings like this, and avoiding costly damage to ingredients during production, can help food and beverage companies maintain their competitive edge during times of challenging economic conditions.