Artisan-quality doughnut balls

IDA, the continuous fryer developed by WP Riehle, produces deep-fried doughnuts in many shapes on an industrial scale. The new equipment offers artisanal quality – the desired white ring at the circumference of doughnut balls, perfect crust and low fat pick-up. The fryer applies unique technologies for heating and turning, and utilises an automatic steam cover developed by the company during the first frying phase. All of tnese contribute to achieving the above-mentioned properties that are characteristic for German types of doughnut balls, also known as Berliner.

IDA is a high performance unit for industrial production from the range of tried-and-tested WP Riehle fryers. This unit is available in various sizes with 15 to 40 baking rows. It has an hourly capacity of between 900 and 4,000 doughnuts with a frying time of six minutes.

Depending on the required degree of automation, there are three different loading systems available: Loading from a cloth table, loading with the use of robots or transfer from a continuous upstream proofer. Independently of the system used, the doughnut balls arrive in the fat in a position that allows them to develop their perfect shape right from the beginning.

From loading to the first turning section, the automatic Riehle steam cover provides for a beneficial climate with a lot of moisture remaining on the dough balls’ surfaces. This is advantageous for the volume of the doughnuts.

The dough pieces are moved and assisted by rods that determine the maximum size of the doughnut balls. The distances between the rods are adjustable and they can be spaced apart upon assembly of the fryer precisely as needed by the individual bakery.

One special feature is the turning unit that can be individually adjusted to the respective product in terms of moving speed and turning features. This novel, programmable turning unit handles the baked goods very carefully and delivers optimally fried products.

If two different types of doughnut (for example balls and circular ones with a hole in the middle) have to be produced, the turning units can be easily repositioned and submerged via two clamps. This minimizes the effort needed for product changeover.

Temperature control in millisecond intervals

Heating coils in the IDA ensure that 100% of the energy is made available for heating the frying fat. These coils are placed at some distance above the fryer vat’s bottom so that solid particles can sink and accumulate in the cooler section in the fryer. This protects the fat from early spoilage. The fryer has different heating zones; the increased energy pick-up of the doughnuts during the first frying phase can be optimally balanced in this way.

The heater’s control uses extremely short switching cycles. The switching time of the electronic solid state relays is in the millisecond range. This means that the surfaces of the heating coils will never reach their maximum temperature. The advantage: uniform temperatures, less fat spoilage and less fat pick-up by the products. For larger plants, it is possible to use gas or thermo-oil for heating.

Integrated central control

The high performance computer control can easily be operated via a clearly arranged glass touchscreen. All modules of the line are integrated into the control; individual parameters including time, temperature and filling levels are stored in the software. At product changeover, the operator simply enters the baking programme, and automatic filling will change automatically. This contributes to more safety when operating deep-fryers with multi-functional use.

The control does not need a VPN connection; simple internet access is all that is required. Remote maintenance of the equipment is also carried out via internet.The administrator can define via passwords the parameters and settings that can be changed by the individual operators. This, too, provides for a high degree of production safety because characteristic properties such as the color of the doughnut can only be changed at the software’s master level.

Filling level control, tank and filter systems

The smaller units are equipped with mobile tanks that are located in the fryer’s base frame. A paper filter system is integrated into these tanks. A hygiene programme ensures that the hot fat is purged and thoroughly filtrated several times a day during production breaks.

The integrated pump is resistant to permanent service temperatures of 200°C and is also responsible for the filling level regulation inside the fat vat. Blocks of solid fat are molten and heated to baking temperature with the integrated tank heater.

Larger units have a filling tank for fat level regulation and a discharge tank. These units are equipped with a stainless steel continuous filtration system. The filters are self-cleaning. This prolongs the shelf life of the fat because sediments are removed and discharged into a separate container.

Quick and easy cleaning

IDA is equipped with a hydraulic lifting device that can be used for removing the transport/heating system completely from the unit thus making the fat vat completely accessible. In case the frying fat is to be reused, it is discharged through a filter into the tank. After the fryer has been completely cleaned, the fat is pumped back into the vat.All units are splash proof for safe cleaning.

Automation on demand

A comprehensive range of additional parts and equipment is also available. Based on the various loading systems, the automatic multiple dosing system for cake doughnuts and other kinds of doughnuts, and the further processing systems including automatic product filling applicator, glazing and sprinkling units, fully automatic production lines can be designed.