| 摘要 |
In preparing dehydrated mashed potatoes having an improved storage life, cooked and crushed potato slices are classified into a core fraction and a peel fraction, or, alternatively, raw potatoes are so classified and each fraction separately cooked, the peel fraction being then separately further crushed, slurried with water, treated to remove peel, eyes and rot, and then dewatered to remove browning precursors, e.g. free starch, soluble reducing sugars, proteins, the clean potato granules produced being mashed with the crushed core fraction to form a homogeneous mixture which is then dried, e.g. in the form of shreds or granules, by exposure to a hot air draught. Preferably, the raw potatoes are initially divided into 3/4 -inch thick slices which are leached for 10 to 15 minutes with water at 180 DEG F. before being steam cooked for 15 to 30 minutes, whereafter the slices are crushed between rolls of 1/8 -inch to 3/8 -inch clearance and divided on a vibrating 1/4 -inch to 7/16 -inch mesh screen for approximately 3 minutes, so that 30% to 70% by weight passes through as a clean core fraction, which is re-crushed between rolls having 0.35 to 0.50 inch clearance, whilst the remaining peel fraction is crushed between rolls of 0.018 to 0.024 inch clearance and then slurried with 1 to 2 parts of water, by weight and screened twice, the first screen having larger apertures, e.g. U.S. screen No. 6 to 14, preferably No. 8, than the second, which preferably has 0.018 to 0.025 inch apertures. The slurry is then dewatered by vacuum filtration and the potato granules combined with the core fraction and dried as stated. |
