Heat exchanger cuts production time for Tahi Honey

Cooling viscous food products is not a simple task and Tahi Honey of Whangarei, NZ, wanted to cool its pure high-grade active Manuka honey to low temperatures.

Knox Henderson, operations manager for Tahi Honey, explained: “Tahi Honey has grown exponentially over the last year, so the need to increase throughput was a priority. In the past we had relied on ambient cooling methods to cream our honey, but this is a time-consuming method suitable only for small batch productions. We approached GEA to help us out in regard to creating a cooling unit that could reduce the temperature of honey by 22°C in order to cream it. This needed to be done as we were doing the final stage of filtering so that the honey was going into the creaming tank at the correct temperature. We also needed the unit to be portable, which presented an additional challenge.”

In this application the challenge of cooling such a viscous product required a different approach, and the newly available HRS Rotex rotating scraped surface heat exchanger provided a perfect solution. Design features in the Rotex such as the helicoidally shaped spiral blade mounted on the scraper bar make it suitable for heating and cooling difficult and viscous food products, helping to reduce pressure drop and pumping power required, at the same time increasing heat transfer coefficients and overall heat exchanger performance. The compact nature of the HRS Rotex also allowed the small skid-mounted system, supplied by GEA Process Engineering NZ, to be portable and easily manoeuvrable.

Commenting on the experiences in cooling the high-grade Manuka honey with the HRS Rotex, Henderson said: “What we received has more than met our requirements and performed better than the figures quoted. The HRS Rotex has no trouble with the viscosity of Manuka honey even at low temperatures and can reduce 40+ degrees honey to well below 20°C while handling a throughput of at least 500 kg/h. With the HRS equipment now in place, we have decreased our production time by 4 days!”

Chris Little, general manager for HRS Australia & New Zealand, said: “HRS is delighted to have collaborated with Tahi Honey and GEA on an interesting and challenging project, and we see this system as another step forward in the Southern Hemisphere food market for HRS and our partners.

“HRS always offers the optimum heat exchanger solution to any heat transfer application and in this instance our exciting new Rotating Scraped Surface Heat Exchanger was clearly the best and most efficient option offering a host of advantages over old plate heat exchanger technology. The flow rate required for Tahi only required our R1 mono tube Rotex; we are looking forward to the next project, which will require our R3 multitube Rotex SSHE, performing a much larger duty in a single compact unit.”