© 2014 Hebenstreit GmbH
© 2014 Hebenstreit GmbH
© 2014 Hebenstreit GmbH
© 2014 Hebenstreit GmbH
© 2014 Hebenstreit GmbH
© 2014 Hebenstreit GmbH

Snack Extrusion Plants

HEBENSTREIT supplies automated extrusion plants for the production of savoury and sweet snacks as well as breakfast cereals.

These are produced on the SE 70 single screw cooking extruder, which has a capacity of 100 – 300 kg of unflavoured snacks per hour, or the SE 110, which has a capacity of 200 – 500 kg per hour.

The innovative construction of the HEBENSTREIT cooking extruders ensures a homogeneous product quality within the above output ranges without any compromise. Depending on the recipe, the required sensory characteristics of the products and the quality requirements in terms of shape, texture and taste, respectively, HEBENSTREIT snack production plants can be used to produce between 120 and 800 kg of finished product per hour.

HEBENSTREIT snack production plants comprise of the following components:
• Raw material mixer with automatic water dosing system according to the specific recipe
• SE single screw cooking extruder
• Conveyor belt or pneumatic conveyor system for conveying the extruded products to the downstream drier
• Drum drier with hot air or infrared drying system
• Conveyor belt or pneumatic conveyor system for conveying the dried products to the downstream flavour drum
• Flavour drum and flavour application system comprised of seasoning preparation and dosing units for covering the dried 
  products with a liquid mixture consisting of seasoning and vegetable oil
• Buffer system for the continuous temporary storage of the flavoured finished products prior to packing

In addition, HEBENSTREIT also supplies the required additional equipment for the production of extruded potato sticks, filled savoury or sweet snacks as well as breakfast cereals:
• Cutting device for sticks
• Dosing, moulding and cutting devices for filled snacks

Please click here for a larger view

SE single screw cooking extruder for the production of savoury or sweet snacks and breakfast cereals

A large selection of dies makes it possible to manufacture products with both simple shapes such as curls, balls, wheels, sticks, rings or rice crispies, and also 3-D shapes or even filled snacks and breakfast cereals

Please click here for a larger view

Layout of an automated HEBENSTREIT snack production plant

Please click here for a larger view

Description of the process
Initially the components for the selected recipe are mixed homogeneously in a batch raw material mixer (1) and then water is added according to the required moisture content. The raw materials used for the production of extruded snacks or breakfast cereals include ground cereal products such as maize/corn, rice and wheat grits, as well as potato flakes or granules. These raw materials, which contain starch, are the main components and they can be combined with other ingredients such as common salt, sugar, cocoa or vegetable powder as well as with flavourings and emulsifiers. This mixture is then fed to an intermediate container (3) by a screw conveyor (2), from which the mixture is then conveyed by another screw conveyor (4) continuously to the hopper of the extruder dosing unit. The dosing unit is equipped with a level sensor. The constant fill level ensures that the mixture is dosed into the extruder very consistently.

The core component of the snack production plant is what is known as the cooking extruder. The key components of the single screw cooking extruder (5) are the dosing unit, the sleeve, the rotating screw, the pressure and die plates and the cutting and temperature control units. In the cooking extrusion process itself, also known as HTST (High Temperature Short Time) extrusion, raw materials containing starches and proteins are plastified at certain moisture contents and undergo structural modifications by the influence of temperature, pressure and shear forces in the barrel of the extruder. Plastification has the effect of thoroughly cooking and gelatinization of the starch in the mixure. Here the pressure and die plates generate very high pressure.

When the plastified mass emerges from the die plate, the moisture in the mixture escapes in the form of vapour, which is what leads to the typical structure of the products. At the same time the mass also expands as a result of the sudden drop in pressure to the ambient pressure level. The extruded products are then given the desired shape and texture by being cut by a rotating knife or a special cutting and moulding device.The entire cooking extrusion process is characterized through adjustable process parameters such as dosing levels, screw speeds, barrel temperatures and cutting speeds.

The pressure and temperature is permanently monitored during the process itself. The temperature in the in-feed zone can be controlled by using a water cooling unit.

The extruded products are then fed to a continuously rotating drum drier (7) via a conveyor belt (6) or pneumatic conveyor system. Drying is necessary, because the products still have a moisture content of 6 – 8% after leaving the die plate. The drying time is only a few minutes, depending on the desired texture, after which the residual moisture content is approx. 1.5 – 3%. The residence time in the drier depends on the selected drum speed and the drying temperature.

The continuously rotating drum drier can be equipped with both a hot air and an infrared drying system. The higher temperatures in infrared drying lead to a roasted taste of the kind required for breakfast cereals. The dried products are then conveyed to a continuously rotating cylindrical flavour drum (9) via a conveyor belt (8) or pneumatic conveyor system, and this drum is equipped with a system comprised of a seasoning preparation system and a dosing unit. Here the dried products are coated with a liquid mixture of seasonings and vegetable oil. Following temporary storage the flavoured products are fed to the downstream packing machines via conveyor systems (10).


Home | Links | Impressum | Privacy Policy

HEBENSTREIT GmbH   |   Hessenring 16   |   64546 Mörfelden-Walldorf   |    Telefon +49 (0) 6105 202-0   |   ©  2016 HEBENSTREIT GmbH