| 摘要 |
A process for producing a spray dried baby food, whole- milk or skim-milk product, comprising the following steps: Atomizing a liquid concentrate of baby food, whole-milk or skim-milk as droplets centrally into the upper part of a drying chamber of which at least the lower pertion is defined by a downward tapering frustro-conical wall; Introducing drying gas a t a temperature of 160-400°C downwards fromt the top of said chamber around the atomized droplets to partially dry these to moist particles and carry them in a downward widering direction; Maintaining a fluidized particle bed at a temperature of 45- 80°C in the bottom of the drying chamber and/or in a lower extension thereof, by means of an upward stream of fluidizing gas drying, classifying and agglomeration of the particles therein; Withdrawing a stream of gas comprising spent drying gas introduced at the top of the chamber and gas from said fluidized bed and at a temperature of 60-95°C form the chamber through flexible filter elements within said chamber, thereby settling fine particles having been entrained by said stream on the surface of the filter elements; Releasing the fine particles settled on the flexible filter elements by short, moderate counter blows to cause them to fall down on the frustro-conical wall at a location at level with or above a horizontal ring-shaped area on said wall where the largest concentration of said moist particles would have reached said wall if no fine particles from the filter elements had fallen down thereon, from which location said fine particles slide downwards along the wall as a covering layer to reach said fluidized particle layer; Withdrawing an agglomerated product from the fluidized bed fulfilling one of the following three combinations of agglomerate size distribution and grains rate described: i) D10 (<10%): 50-100ìm, D50 (<50%): 150-225ìm, D90 (<90%): 350-450ìm and grains= 1; ii) D10(<10%): 100-200ìm, D50(<50%): 225-400ìm, D90(<90%): 450-600ìm and grains above 1 but below or equal to 2; iii) D10(<10%): 200-300ìm, D50(<50%): 400-600ìm, D90(<90%): 600-900ìm and grains above 2 but below or equal to 3.
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