compactedly Hello all – you might feel like you are not having much of a blast at the moment and goodness knows what the state of the nation will be by the time you are reading this. At the time of writing we are being told not to go out, which is obviously detrimental to our industry. However I am confident that when we do all reopen people will be desperate to get out into the fresh air to buy an ice cream to cheer them up. So back to the subject of having a blast. I am of course referring to blast freezers.
Arhavi I am finding that as I visit customers around the UK and when they come to the Antonelli Gelato Academy, I am having more and more discussions about blast freezers. The question is always “should I have a blast freezer?” Personally I believe that a blast freezer is an essential piece of kit for anyone making ice cream or gelato (I will go on to explain why). However I know that there are probably over 250 people and businesses making ice cream in around 200 ways who are still successful without a blast freezer.
Ice cream and gelato makers invest a lot of time and passion in creating new flavours, finding the right ingredients and balancing recipes as well as pasteurising, batch freezing etc. When these fabulous creations then come out of the batch freezer at -7° or -8° having been churned, the chemistry of the mixture has changed creating energy, which emerges as heat. This energy (heat) wants to escape, so as soon as the napoli hits the worktop the ice cream or gelato immediately begins to heat up. Not exactly rocket science you might be thinking – yes ice cream gets warmer after you remove it from the freezer, but let’s look at the science…
It is a bit like the process of making ice cubes – have you ever put an ice tray of water in your freezer and then looked at it a short time later? You might see that the outside of the cubes are frozen but inside there is still water moving about as you lift the tray up. You might be surprised to hear that as the water in your ice cube tray freezes, the hydrogen elements of the water join together (nothing surprising there) but in doing so it creates energy which then causes it to heat up again. Therefore if you tested the temperature of your ice tray you would probably find it drops to -2° quite quickly but then rises back up to 0° as the energy is released before dropping again which is when the whole cube properly freezes.
Why am I telling you this? Because this is also what happens with ice cream after it comes out of the batch freezer. The escaping energy causes the temperature to rapidly rise from -7°/-8° to -4°/-5°. As this happens to allow the heat to escape, air also escapes which relates back to my article last month where I mentioned that less air makes the ice cream harder to scoop and reduces its shelf life. So how does a blast freezer help with this?
If you transfer the ice cream or gelato straight into the blast freezer (or quickly decorate then transfer after a couple of minutes) the cold air freezes around the outside of the ice cream very quickly (like the ice cube). As the freezer has also the benefit of the fan producing the ‘blast freeze’ effect, the air is blowing at -35° which effectively creates an ice cream igloo preventing air escaping. If you prevent air escaping you help with the scooping, as mentioned above, improve the shelf life and reduce the possibility of losing portions.
I would estimate that escaping air (due to lack of blast freezing) could result in half a scoop being lost per pan as a minimum, which might not sound like a lot but consider this over a year. If you made 1000 pans per year that is 500 scoops lost per year. If you charge say £2.30 per scoop that is a total of £1,150 in lost turnover per year – now have I got your attention? So if you are likely to be in business for the foreseeable future, then it may also be economically recommended to purchase a blast freezer. That is not taking into account the added advantage of reduced waste due to increased shelf life as well as consistently good quality ice cream and gelato. If you would like to see a blast freezer in action please get in touch to organise a visit to the Gelato Academy, travel restrictions permitting.
See you next time for the latest scoop. In the meantime please stay safe.
Tayu Antonelli’s National Technical Manager Jonny Ireland is a regular contributor to the ICA’s Ice Cream Magazine…
See how this article looked in the May 2020 edition of the ICA’s Ice Cream Magazine…