Dipl.-Ing. Johannes Strunz
is sales engineer at amixon GmbH
Without doubt, certain groups in society are leaning towards meat-reduced or meat-free diets. There is there-fore a growth in meat substitute products. Many consumers wish to avoid meat for many different reasons and are choosing alternatives. On the one hand there is the vegetarian group, which avoids meat on the basis of animal welfare. Factory animal farming is rejected on ethical grounds. Others argue that meat and sausages from factory-farmed animals are less healthy, not least because of prophylactically administered animal medicines. In the light of the current climate discussion there is an ever-increasing proportion of con-sumers who would like to go vegetarian or even vegan because of the rapidly increasing world population and growing pressures on the environment. They aim to reduce their CO2 footprint as far as possible. Facto-ry farming generates a considerable proportion of the CO2 emissions. According to the German Federal En-vironment Agency, a vegetarian diet would improve the climate balance in Germany per head by approx. 600 kg CO2 which would correspond to a CO2 saving of 30%. ;
Established meat processors and start-ups alike are exploring the idea of creating meat products using plant-based raw materials. And some of the global players from the food industry are backing the trend and put-ting considerable financial resources into in-house development to produce the perfect meat imitation. To an increasing degree, vegetarian sausages need not fear comparison with traditionally produced products.
There is still a way to go however before we can create something that resembles a meat-based schnitzel, steak or burger in shape, consistency and taste. The customer should not have to miss any of the charac-teristics of the meat product in the vegetarian or even vegan alternatives. The texture and even the aroma of the assumed "original" must be replicated. Preparation itself, on the grill or in the pan, should be perceived to be as authentic as possible. Even fast food chains now have veggie products firmly established on their menus.
Meat replacement products are generally highly-processed foods, in whose manufacture the mixing process is the quality-defining process stage. Basic mixes for these kinds of products often contain more than 30 components (dry, semi-dry and liquid), whose physical properties vary hugely in terms of density, particle size, rheology and stability. The premixes being produced are pure dry mixes while the premixes of other product types already contain a high proportion of liquid, resulting in a pasty, mushy mass.
Bear in mind also that a continuous transferring and packaging process requires continuous mass preparati-on, particularly when the products do not flow easily, are sticky or whose contact with atmospheric oxygen needs to be kept to a minimum.
And continuous preparation processes are all the more difficult, the more individual components are involved in the mixing process. It often makes the most sense to prepare interim batches of the majority of the solid components because, unlike liquids, it is very much more complicated to automate and dispense powdered products.
The AMK continuous mixer from amixon can also be used as a precision batch mixer.
For this purpose, amixon® offers a state of the art continuous-mixing system which can also be used simultaneously as a precision batch mixer. It is a conical and cylindrical vessel with a centrally-mounted rotating helical mixing tool. The mixer rests on load cells. The discharge at the bottom is fitted with a zero-clearance closure devices. This is opened or closed in accordance with the weight data, thus ensuring a constant filling level. Gravimetric powder dispensers are fitted above the mixer.
The continuous mixer from amixon® is characterised in that from the start to the end of the run, only “quality product” is produced. There is no waste, either at the start or at the end of the mixing process. The process is described next: The discharge device of the mixer is closed. All the gravimetry working dosing components are started simultaneously with small mass flow and tune themselves automatically in relation to one another. The level of the mixing container fills up continuously, starting up the mixer when it reaches half capacity. Tuning is completed once the mixer is filled to about half its capacity. The discharge device opens slowly once the mixer is filled at approx. 80 % of cubic capacity. A filling level of 80% is kept constant. The dosing flows are increased up to the maximum mass flow while maintaining a constant synchronisation. The process at the end of a product run is as follows: All dosing devices gradually slow down the mass flow and then switch off and close at the same time. The mixer discharges the mixture continuously until it is completely empty. Free-flowing goods flow out completely.