While Berg was able to start with a standard product, specific modifications were necessary to suit the juice products to be processed at Sepallo Foods. For example, because the juice product would be in direct contact with the icemaker, daily cleaning and sanitation were paramount concerns. The machine would require daily flushing of the distribution lines and contact surfaces with high-pressure washers and sanitizing agents.

Another concern was the ability of the juice to flow through the distribution lines and coat the freezing surfaces (evaporators) with the juice to produce frozen fragments of “juice ice,” which would be mobilized easily at a later time for further processing. A third concern was whether the icemaker could freeze a product with such a high level of solids, and to what extent the icemaker could maintain a consistent concentration of juice, both throughout the frozen nugget and from batch to batch.

Berg had not previously frozen a product with so much particulate matter using its shell icemaker machine, so the company asked Sepallo to deliver a usable sample of the product to run through a conventional unit. From those tests, Berg would be able to determine what modifications would be required in the final solution.

Because pure water freezes first in the ice-making process, Berg was concerned that the juice solids would wash off the tubes to concentrate in the recirculation tank (as occurs when ice cubes are formed). The company also was concerned that the juice product would not freeze well to the tube surface and would result in producing juice slush rather than a hard frozen juice nugget. To address the preliminary concerns about the juice product, only a few modifications were required to prepare the conventional icemaker for the test. One involved opening the distribution nozzles to allow the solids to pass through and coat the tubes evenly with juice. The other was to ensure that there was ample refrigeration capacity. The presence of an abundance of solids in the juice would mean that the freeze point of the juice liquid would be lower than pure water. Berg needed to ensure that the tube surface would get cold enough so that the liquid and solids would freeze as one homogeneous product on the evaporator tubes, leaving little opportunity for the solids to wash off.

After some minor adjustments with the process timing controls, Berg was able to accomplish the desired results. The concentration of juice solids remained practically the same as the liquid juice supplied to the ice machine. Additionally, the juice was hard frozen into manageable nuggets that were easily conveyed.

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