Spiral freezer mechanically transport products through a freezing process that rapidly decreases the temperature of the product prior to transportation or refrigerated storage. Unlike tunnel freezers, which require a linear wire-mesh belt that conveys the product through a sub-zero blast-freezing room, spiral freezers utilize self-stacking and multi-tiered conveyor belts to maintain product quality and minimize refrigeration space required in the plant.
Using either mechanical or cryogenic refrigeration methods, a spiral freezer uses high-velocity air pumped over the product in a crossflow or downflow configuration to quickly transfer heat and cool the food for transport or storage. This design allows the freezer to operate at a faster rate than a conventional tunnel or walk-in freezer and results in a higher volume of product processed per hour, reduced inventory loss and improved production efficiencies.
Many spiral freezer manufacturers offer some level of size customization, enabling them to provide customers with a machine that meets the needs of their specific operations. For example, some spiral freezer manufacturers are able to modify the width of their conveyors or number of tiers in the machine to better fit the requirements of specific production lines and/or product applications. This type of customizability is a great way for companies to increase the productivity and efficiency of their existing equipment without having to invest in a brand-new freezer.
The ability to customize a spiral freezer to the requirements of a company’s production processes and/or product applications also helps businesses save money on utility costs. In particular, spiral freezers are often used for product changeovers, when the defined parameters for the freezer need to be adjusted. In these situations, it is common for the freezer setpoint to be lowered and fan speeds to be increased in an effort to quickly bring the product up to the correct temperature. However, these changes can result in warm (or soft) product that fails quality checks and reduces the workflow for other departments responsible for the analysis and testing of that product.
In addition, a high-efficiency spiral freezer can minimize waste and energy usage by ensuring that the coldest air is exposed to all surfaces of the frozen product at all times. This feature is possible due to the freezer’s low-pressure, high-velocity, impingement and vapor flow refrigeration system, which provides each tier of product with colder air directly from the freezer’s evaporator. This ensures a rapid chill and lower product dehydration, less product weight loss, and better overall product quality delivered to the end customer. This design also significantly reduces the freezer’s operating cost and energy consumption compared to cryogenic or nitrogen freezers.