The Benefits of Shock Freezing

When your artisan ice cream leaves the batch freezer, it’s probably at a temperature around –7°C. Whether you are going to deep freeze your ice cream to –18°C for long term storage or distribution, or whether you are going to put it straight into a display cabinet, a shock freezer will:

• help keep your product quality
• help keep your overrun
• help improve product display in a cabinet
• help speed up production time.

The trend in Italy at present is to pile up the fresh ice cream out of the batch freezer into the ice cream pan in peaks before putting it into the display cabinet. Due to the time it takes for this ice cream to freeze down to the –12/–14°C temperature of the cabinet, the peaks can flop and some of the overrun lost. Put the piled up ice cream into the shock freezer for less than 30 minutes and a hardened crust will form over the whole pan and the ice cream will keep its attractive look whilst the core temperature is reducing down to that of the cabinet.

When the ice cream is removed from the batch freezer at approximately –7°C, there are still a lot of water molecules that are semi-liquid, and the faster this water is frozen down to –18°C, the smaller the ice crystals that will be formed. The smaller, micro crystals will mean that, the ice cream once thawed to serving temperature after storage, will retain more of its original structure. The smaller crystals reduce the damage caused by freezing so the quality of the thawed product is higher.

It also:

• increases cost-efficiency because you can buy ingredients in bulk and store the finished ice cream for longer knowing the quality will be retained
• increases time-efficiency because you can make ice cream during the low season and store them to use in the high season and still benefit from a good quality product

Shock freezing has benefits in other areas of food production too. A blast freezer can typically take a product from +90°C to –18°C in around four hours. Because the ice crystals that form during this process are so small, you can freeze cooked, partially cooked and uncooked products safe in the knowledge they won’t be affected by the freezing process. It’s therefore ideal for pastry chefs, bakers and restaurants because it means:

• greater time efficiency because you can prepare products when it suits you
• greater cost efficiency because you can buy and prepare in bulk
• reduced waste
• higher hygiene standards
• constant product availability.