Fryers must maintain temperature control and remove particulars to achieve appealing and healthy fried goods.

Influencing yet another category of bakery and snack equipment, the health-and-wellness trend reshapes how frying systems are engineered and operated. Healthier snacking and more snacking overall put new demands on the ability of fryers to output quality products at ever higher production rates.

“A lot of the current trends in the development of frying equipment are driven by the consumer,” said Arnaud Jansse, applications engineer, Florigo Industry, a TNA company. He cited demand for healthier snacks and the need to reduce potentially harmful chemicals, such as acrylamide, as prompting major advances in the technology.

But there’s also a drive for higher volume and flexibility. “Bakers want to be able to make a wide variety of products on their lines,” said David Moline, sales and marketing manager, Moline Machinery, LLC. “They want flexibility in sizes and styles from mini donuts to large fritters or submerged products. Second, they want the ability to run 24/7 for weeks at a time with minimal operator involvement. This is especially true for dedicated lines. The baker wants to get operating costs and product costs as low as possible.”

Flexibility also reigns in the snack chip world, and that includes the foods being fried, according to Mr. Jansse. “As more and more consumers expect a greater variety on the supermarket shelf, snack manufacturers have also started looking for frying equipment that is able to handle different volumes and a variety of raw materials like sweet potatoes and fruits, and a range of shapes,” he said.

He noted as well that ease of operation and maintenance make a big difference when running chips at peak speeds. And there’s the cost of production to consider, too. The technology must use less energy, water and oil than older systems to reduce overall production costs and ensure a more profitable and sustainable process.

Expanding dimensions, automation
Your eyes are not deceiving you: Fryer lines are getting ­bigger … much bigger.

That’s how bakers and snack manufacturers want them. “We’re usually asked how large the capacity of the line is,” Mr. Moline added. “The larger producers have a need for very high-volume, low-production-cost systems.”

High-volume industrial donut fryers, for example, now extend 18 to 40 ft long, with the capacity to make 10,000 to 20,000 donuts per hour, “with even greater capacities for mini donuts,” Belshaw Adamatic noted in a recent company statement. It described the industrial donut line that it manufacturers in partnership with JBT FoodTech as the largest in the market today. The TTF-IV electrically heated fryer operates with very low shortening volume plus a continuous shortening filtration and a sediment removal system as options. It uses JBT FoodTech’s THERMoFIN heat exchanger technology. It is specifically designed to use trans-fat-free donut frying shortenings.

The company’s own Belshaw High Volume is no slouch either. Fryer lengths range from 18 to 32 ft and 42-in. wide. They can produce 2,000+ dozen donuts per hour. The system features a turbo premix gas heating system, PLC control and sediment extraction.

At Moline, the company’s Libra fryers offer capacities ranging from 400 to 4,500 dozen donuts per hour for standard lengths of 13 to more than 40 ft. These large fryers feature electric, gas or dual-fuel heating options. “Natural gas is an economical heating option with fast recovery, while electric heating elements provide precise control and stable temperature differentials, eliminating side-to-side fluctuations,” the company stated.

For kettle-style potato chips, Heat and Control’s MasterTherm kettle fryers answer consumer demand with output capacities exceeding 500 lb per hour and repeatable quality from batch to batch, according to company. Its thermal fluid heat exchanger, which is immersed in the cooking oil, employs thermal fluid technology to gently heat oil uniformly throughout the fryer. Each heating tube expands independently to help prevent thermal stress damage.

Features include continuous fines removal, ­automatic oil level control, fully enclosed hood, an exhaust stack Oil Mist Eliminator, a clean-in-place spray system and screw jack hoists to safely raise the hood and heat exchanger for complete access.

At WP Bakery Group USA, the company’s Largo industrial donut fryer can be configured with 43 to 80 trays or bars, thus outputting 4,000 to 40,000 pieces per hour for products ranging in weight from 0.6 to 2.5 oz (17 to 70 g). Its automatic feeding system moves donuts straight from the proofer into the fryer and out to cooling. Options include a suction hood, a fire extinguisher using foam or water mist and a thermal oil/frying oil heat exchanger.

It’s not just the biggest fryers that are undergoing improvement. WP showed major changes in its Riehle kettle fryers at the 2016 International Baking Industry Exposition. The Linie 2000A replaces manual donut fryers with a fully automatic system. All the operator needs to do is load raw donuts onto the unit’s dump tray and press a control panel button to lower the filled tray into the oil and shut the steam lid.

“All turns are done automatically, and as many as four turns can be programmed to be made,” said Patricia Kennedy, president, WP Bakery Group USA. “There’s no need for an operator wielding ‘chopsticks’ to turn products.” The tray rises out of the oil at a preset time, allows the donuts to drain briefly and then moves over to the cooling table where the tray then deposits the finished donuts.

Answering acrylamides
The plus side of frying can be seen in the continuing popularity of the foods made by this process; the minus side involves things not seen, specifically acrylamides. When frying or baking a sugary, starchy food, the high temperatures can turn the amino acid asparagine into acrylamide, a known carcinogen.

“Gaining a greater level of control over the frying process is key,” Mr. Jansse said. For its chip fryers, Florigo developed flow control technology to accurately regulate the dwell time of chips in the hot oil. It is coupled with precise temperature control via double heat exchangers. “It’s possible to lower the temperature right at the end of the frying process and, therefore, reduce the formation of acrylamide by up to 50%,” he explained.

Taking another approach, vacuum fryers continuously cook products at a low temperature, around 260°F and under low pressure conditions from start to finish. “Temperature-related reactions like the Maillard reaction and acrylamide formation are slowed down significantly,” Mr. Jansse said.