A new ‘soft chill’ means of using liquid nitrogen to control the temperature of foods while they are being processed will improve quality, says Air Products.

The company believes this is possible even when used with the most heat-sensitive or reactive foods – and has further developed its own Freshline® LIN-IS (Liquid Nitrogen Injection Solution) as a result.

As an effective refrigerant, liquid nitrogen has long been used to help control the temperature of a wide range of food products while they are being processed. The liquid nitrogen is usually injected into the bottom of the food mix at intervals in order to keep it cool and its temperature is regulated.

For some heat-sensitive or reactive food products, however, such as dough, Air Products has found that temperature control can be significantly improved by vaporising liquid nitrogen over the top of the mix – as well as injecting it into the mix itself.

In view of this, Air Products has refined its existing Freshline® LIN-IS (Liquid Nitrogen Injection Solution) so it is capable of offering either top or bottom injection as part of a tailor-made process solution.

Ann Callens, European food sector specialist at Air Products, explained, “We discovered that by vaporising liquid nitrogen over the top of the foods being processed we could achieve a softer chill ideal for sensitive products such as doughs. This method of chilling can also help to reduce air bubbles in foam-sensitive products such as creamy sauces.”

“As consumer tastes become more sophisticated, food processors are looking for solutions that can deliver a high-quality and consistent food product, while ensuring the highest safety standards. Top injection technology, when used as part of a complete chilling solution, can achieve this even when working with the most sensitive foods. The fact that it can be retrofitted to existing chilling systems means it is easy to install too.”

Freshline® LIN-IS technology was originally developed 10 years ago.