Spiral mixers

In batch processing, the various additives are mixed with the prepolymer component in a jacketed horizontal (Z-blade) or vertical (helicone or spiral) mixer. Prior to this, however, a high-speed liquid mixer is used to dis-... 

Spiral mixers offered the small baker the opportunity to produce no time or short time doughs without the use of specialised improvers (Figure 1). These machines have helped to keep small bakers in business. 

The next development in the bread dough mixer story was the spiral mixer. These mixers are so-called because they use a spiral element to mix the dough. They provide a more gentle mix than a Tweedy mixer, but a spiral mixer can usually deliver in under 15 min a developed... 

When potassium bromate was struck off the UK permitted list in 1990 the ADD process was no longer viable. Unsuccessful attempts were made to use ascorbic acid with or without azodicarbonamide. ADD then is only a viable method where potassium bromate is allowed. As the continued use of potassium bromate comes under further pressure then scope for using the ADD method decreases. Those bakers who had used ADD almost certainly did not go to the bulk fermentation process but moved to using a spiral mixer. 

A further development from ADD methods is the use of spiral mixers by small bakers. These machines put energy into the dough less rapidly than the sort of mixer used in the Chorleywood process but a spiral mixer is less expensive and more versatile. The actual dough development time will always depend on the recipe, the flour improver and the flour but, for comparison, while a Chorleywood mixer will develop a dough in 2-5 min a spiral mixer will take 8-15 min. 

The spiral mixer process is sometimes called the continental no time process because these mixers originated in continental Europe where small bakers are much more common. Neither L-cysteine nor potassium bromate are needed. The only flour treatment needed is ascorbic acid. 

Typically this sort of product would be made using a spiral mixer with a specially formulated bread improver. The other requirements are the moulds to shape the dough and an oven with steam. 

The dough was mixed for about 8 min in a spiral mixer (Kemper) at 26 "C and 80 % rH. Four loaves were formed, allowed for two fermentation periods (40 resp. 70 min) at 34 C and 80 % rH, and then baked (30 min at 225 "C) in a rotary oven (Siemens). After one hour of cooling about 90 g slices were packed in baker s paper and aluminum foil, and afterwards kept in cold storage for max fourteen days until sampling. 

Spheripol, Process for producing polypropylene, Montell North America Spinner, Locking ring valve, Zeiger Industries Spiral Mixer, Motionless static mixer, TAH Industries, Inc. 

Typical batch mixers include planetary mixer [shear] blade (Helen) mixer [convection shear] blade (double-arm) mixer [convection shear] paddle (pan-type) mixer [shear] paddle (Marion) mixer [shear diffusion] tumbler (drum) mixer [shear, diffusion] tumbler (double-cone) mixer [shear] tumbler (twin-shell) mixer [shear] Muller mixer [shear] mill mixer [shear] ribbon mixer [convection diffusion] vertical spiral mixer [convection diffusion] Nautal mixer [convection diffusion] Banbury mixer [shear] airmix mixer [convection diffusion] Lodige mixer [shear diffusion] gravity mixer [convection] and vibratory mixer [convection shear]. 

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