Liquid nitrogen (LIN) at -196oC is the core component in cryogenically freezing a wide range of edible products – ranging from fresh meat, fish and poultry – to dairy, fresh produce and ready meals.
Afrox applications engineer, Hendrik Pretorius, indicates that LIN is essential not only in maintaining quality, but also reducing product clumping and ice crystal formations.
“Through the cryogenic freezing process, products enter the freezer and are cooled using LIN circulated at high-speed by specialised fans to lock in the moisture and flavour. The LIN is then vaporised on the product to reduce its surface temperature and ensure fast freezing,” he states.
According to Pretorius, this process results in considerably lower cell deterioration, when compared to more traditional freezing methods, due to the formation of smaller ice crystals.
“What’s more, the end-product also experiences reduced drip loss and dehydration, which contributes significantly towards achieving a texture and flavour that is almost identical to the fresh item.”
Proven performance at the Dr. Oetker SA production line
The South African division of Dr. Oetker – an international market leader that specialises in frozen pizzas, spinach products and ready-meals – recently upgraded its Johannesburg-based production facility by installing the advanced new-generation Afrox Cryoline XF spiral freezer.
Dr. Oetker South Africa general manager, Max Kerssenbrock, reveals that the company is committed to maintaining the highest standards of quality. “In order to constantly improve our offering to the consumer, we upgraded our production line by installing the Afrox spiral freezer.”
Kerssenbrock indicates that the Afrox Cryoline XF spiral freezer shock-freezes the product to lock in the freshness of the high-quality ingredients. He said, “The product comes straight out of the bakery, comprised of freshly-baked dough and toppings, which are all frozen to -18oC within minutes.”
According to Kerssenbrock, this is the optimal temperature at which to freeze the product, in order to ensure that quality is maintained throughout the supply chain, and that the consumer is guaranteed the original freshness on their plates, even months later.
“Afrox has been a value-added partner to Dr. Oetker for many years. The company is a trusted supplier of nitrogen as a raw material to our operation, and the installation and commissioning of the new spiral freezer makes Afrox a one-stop-shop for all freezing solutions,” says Kerssenbrock.
The new-generation Cryoline XF spiral freezer boasts high-capacity with minimal floor space. Pretorius highlights the fact that advanced technology enables the system to deliver up to three times the heat-transfer rates of traditional spiral freezers.
“This cryogen efficient power-on-demand ensures energy savings, which is important in South Africa, where unreliable electricity supply is a major concern. Another advantage of this technology is that it reduces the need for maintenance, thereby minimising overhead costs,” he says.
Another innovative new cryogenic freeing solution from Afrox is the Cyroline CW Cryowave freezer, which is designed for energy-efficient, individual quick frozen (IQF) product freezing. It boasts a patented vibratory wave action for product vibration and agitation within the refrigeration medium to produce rapid and uniform heat transfer times, as well as shorter freezing times, to ensure improved product yield and enhanced product quality.
Cryoline freezers from Afrox are designed and manufactured with hygiene in mind. These design features make the freezer compliant with numerous international hygiene and sanitary standards, including the American Meat Institute guidelines, the European Hygienic Engineering and Design Group standards and the Hazard Analysis and Critical Control Points standards.
Although cryogenic freezing is a niche market with product-specific requirements, Pretorius is confident of Afrox increasing its market share. “Afrox’s service offering includes a range of cryogenic freezing solutions, cryogen supply and fit-for-purpose installations. As high-quality frozen convenience foods continue to gain popularity, Afrox remains committed to manufacturing technically-advanced, tailor-made solutions for numerous industries,” he concludes.