The Technical Ice Showcase Guide - Part 1

If the ice cream machine is the heart of your ice cream production, the ice cream display case is the figurehead. Because ice cream is and remains an impulse product - you don't buy it because you need it, but because you want it.

That's why you should never skimp on the ice cream display case - because what good is the best ice cream if no one wants to try it? You can find more on this topic in our blog article "Nobody needs ice cream! Why presentation is so important with ice cream"..

This time we would like to look at the technical differences between the various ice cream display cases: What are the advantages and disadvantages of double or single recirculation? Why is the number of evaporators important? Which unit is the right one for me - 230V or 400V, internal or external, air- or water-cooled? And what is the difference between a high-quality and an inexpensive ice cream display case?

And because the whole thing is so extensive, we're splitting it into two parts.

The choice of circulating air - single or double

Let's start with a difficult and often debated question among ice cream professionals: Which is better, single or double convection?

The answer is as simple or as difficult as the question of front- and rear-wheel drive in a car - there is no clear answer. We will try to explain it to you briefly.

Single recirculation - ital. singula ventilazione - means that a single stream of cold air is directed over the top of both rows of ice trays - the front and the rear. In the case of double recirculation - doppia ventilazione - a second auxiliary air flow is generated by an air outlet between the two rows. This means that each row, front and rear, has its own cold air flow. The diagrams below illustrate this difference.

Theoretically , two air streams, i.e. double recirculation, ensure a more even temperature in the display case than single recirculation. The difference between the warmest and coldest point is smaller, the ice has the same temperature everywhere and thus - provided the ice is balanced correctly and evenly - also the same firmness everywhere.

On the other hand, a double recirculating air unit is also more complex in design and therefore usually more expensive than a single recirculating air unit.

Basically, however, it is the case that an excellently designed, single recirculation unit with optimum airflow and high-quality cooling components often works at least as well as a double recirculation unit.

In practice, this question is therefore rather "academic" and has very little practical relevance - other technical aspects have much more influence on the function of the showcase.

Which is better for mountain ice?

More relevant for the overall performance of the display case and for the often-asked question of which display case is best suited for high-build "mountain ice cream" is, in addition to the aforementioned optimisation of the air flow and the high-quality components, the inclination of the egg trays and the height of the air flow.

Thehigher the airflow is ejected, the higher you can build up the ice without it becoming soft - quite simple in principle.

In principle? Yes, because on the one hand, a higher air flow requires a higher volume flow and thus consumes more energy - on the other hand, for better visibility, the ice cream should also be tilted towards the customer and "rest" as far up on the display case as possible (instead of being "sunk" into the display case).

Both in turn bring the ice "higher" and closer to the air outlet - so it cannot be built up as high again.

Sounds complicated? Yes, technically it is.

In summary, it simply depends on the overall construction of a display case how well it is suited for salvage ice and how high you can build it. However, the suitability for particularly high mountain ice is usually always bought with other disadvantages - be it higher energy consumption, a lower inclination of the ice or simply a higher price.

In fact, the best way is usually to work with a professional to select the optimal display case for "your" ice cream.

The number of evaporators

However, the number of evaporators makes a fundamental difference in price and quality. Simply put, the evaporator is the component that generates the cold and brings it into the showcase - and the air is coldest directly or close to the evaporator.

Inexpensive ice cream display cases - the entry-level models of many premium manufacturers, and often all models of less expensive manufacturers - have only one evaporator. The cold air must therefore make a full revolution in the display case, above and below over both rows of trays, until it is cooled again at the evaporator. Since the air gives off cold in the process, it gets warmer and warmer, and thus the cooling capacity decreases in the course of the rotation.

In a showcase with only one evaporator , the temperature stability will therefore always be significantly worse than with two evaporators.

Why? In showcases with two evaporators, there is usually one evaporator at the front and one at the back, so that the air flow is always (approximately) equally cold. Logically, this costs more money - after all, two evaporators are installed instead of one - but it also ensures a much(!) more even temperature in the display case.

If this is combined with an intelligent defrosting system that defrosts only one of the two evaporators at a time, the temperature stability is further improved because the second, non-defrosted evaporator can supply cold again immediately after the end of the defrost cycle and cool the ice cream. The thermal shock to the ice cream is thus minimised.

So you see: two vaporisers are more expensive, but technically much better than just one.

And that's what you'll read in Part 2:

In the second part of our "Ice Cream Display Cabinet Guide", we look at the question of the unit (internal or external, 230 V or 400 V, air-cooled or water-cooled) and the difference between high-quality and inexpensive ice cream display cabinets.