Speed cooling pays off
Cryogenic chilling helps processors reach food safety and efficiency goals.
The way the food industry chills cooked liquid foods is changing. Here’s why.
Over the past few years, many meat and poultry processors started chilling blenders and mixers from the bottom using the rapid chilling of liquid nitrogen (LIN). More recently, they started adopting new cryogenic bottom-injection (BI) mixer chilling systems that are hygienically designed to seal the injectors against moisture and food particles.
Advanced hygienic design makes cryogenic BI mixer chilling ideal not just for ground meat products, but even for many wet mixes, such as for burritos and tacos. So, the ways in which meat & poultry and prepared foods are processed are converging. Some major meat, poultry and seafood processors also process proteins for soups, sauces and gravies. For example, one major meat processor packages fully cooked chicken breast topped with gravy into microwaveable entrées. This crossover can go both ways, meaning chilling practices proven in one segment can be quietly adopted in another.
At the same time, an interest in healthy eating habits and ethnic foods is spurring the growth of cooked vegetable-based protein products using bean pastes or mixes (such as in Mexican foods), avocados (such as in guacamole) and chickpeas (for hummus). These all require rapid chilling. The competition can be intense in prepared foods, and BI chilling systems can remove BTUs from foods in mixers/blenders more quickly and effectively than alterative chilling methods.
New BI systems can be equipped to use either LIN or carbon dioxide (CO2) – and they can deliver rapid chilling with batch temperature control in the range of 1 oF. More consistent temperatures at the mixer/blender mean more consistent product quality and smoother downstream processing. Cryogenic BI mixer chilling systems can be used to rapidly chill all types of heavy pastes and high-moisture moist foods. However, for pumpable hot liquids such as sauces, soups, gravies and marinades, there can be an even better way.
The Invisible Bottleneck
In the prepared foods industry, cooked liquid foods are often pumped and batch-chilled in separate cooling kettles, or inline using expensive scraped-surface heat exchangers. Even though the latter can be time consuming to clean and maintain, production may, in fact, appear to be running smoothly. Yet with either of these traditional batch or inline methods, there can be an invisible bottleneck.
It is invisible because food safety guidelines define a window for safely cooling liquids after cooking and before packaging. If a liquid product is chilled within that timeframe, the safety guideline is met. So why chill any faster?
With the new Food Safety & Modernization Act requirements that focus on prevention, safety remains top priority. More rapid chilling ensures time and temperature requirements are met to inhibit pathogen growth. At the same time, the competition in prepared foods appears to be intensifying with hundreds of chilled and frozen foods that include sauces, gravies, purees, specialty beverages, etc. introduced every year. Leaders and innovators know that those who can achieve high quality and efficiency at high volume gain a market advantage. If they don’t adopt new technology that gives them an edge, the competition will.
New cryogenic inline sauce cooling systems are now available that integrate with existing cooking processes. It is now possible to cool 3,000 lbs. of sauce from 190°F to below 40°F in about 20 minutes rather 40-50 minutes or more. Like BI chilling systems, inline systems use injectors, but in this case they chill liquid foods as they flow to the next stage in production.
Cryogenic cooling technology is helping food processors speed production while maintaining or improving food quality and food safety. The selection of batch or inline cooling processes will depend on a variety of factors including: type of food, production rates, viscosity, solids content, moisture levels and pH, to name a few. Either type can be a boon to productivity, and processors using traditional cooling methods will find “speed cooling” a valuable change.
For more information, visit Linde (www.lindefood.com), or call (800) 755-9277.
Erik Fihlman is Program Manager, Bakery and Prepared Foods, for the food and beverage group of Linde LLC where he leads the commercialization of new solutions-based technologies and marketing programs. He is based in Murray Hill, NJ.