The bakery and biscuits line, station by station.

A bakery and biscuit line turns flour, water, fat and sugar into wrapped, cartoned products, and the oven sets the pace for every machine before and after it. The line begins with the dough mixer. Ingredients are weighed from silos and dosing systems into spiral, horizontal or continuous mixers. Bread doughs need gluten development; biscuit doughs need fat and sugar dispersed without toughening the dough. Dough temperature is controlled because it affects how the dough behaves in later machines. After mixing, dough is divided, sheeted, laminated, moulded, rotary-cut or deposited, and bread products are proved. The tunnel oven comes next. Product travels on a steel or mesh band through heating zones set to build volume, set structure and develop colour. Direct-fired, indirect-fired, convection and hybrid ovens each suit different products. Because the oven is long and expensive, its band width and length usually define the output of the whole line. After baking, sanitary conveyors carry product through cooling. Biscuits, bread and cakes must cool to the right temperature before packing, or moisture condenses inside the pack and shortens shelf life. Cooling conveyors also stack biscuits on edge, align products and feed them to the wrappers at an even rate. Wrapping machines, usually horizontal flow wrappers, wrap slugs of biscuits, individual cakes, bars or loaves in film, sometimes with gas flushing. Automatic infeeds that place product gently into the wrapper are critical for speed and low breakage. Wrapped packs then pass through a metal detector, which checks for metal from mixers, cutters and bands before the product goes into secondary packaging. Inspecting individual packs means a reject removes only one pack, not a whole carton. Cartoning machines then load packs into retail cartons for products such as biscuit assortments and snack bars, and case packers load cartons or wrapped packs into shipping cases. From there, cases go to coding, palletising and dispatch.