GB566828A - Improvements in or relating to the production of dried potato - Google Patents

Abstract

In the preparation of dry mashed potato, which can be reconstituted by the addition of hot water, diluted mashed potato is passed through a fine sieve before drying, the cooking, mashing, sieving and drying being effected by means which do not damage the cells. The potatoes are cooked by steam or in water, or milk and water. Dilution is effected, before or after mashing, with the cooking liquor, water or a nutrient liquid such as milk separated milk or whey, the cooked potatoes being preferably extruded into the hot diluent with constant stirring. For spray drying, sufficient liquid is added to bring the weight up to about 1 1/2 -2 times the raw weight of the potatoes. The sludge is then forced through a sieve of 1/30"-1/16" mesh as by means of a brush, metal helix or metal or rubber paddles, or by cake mixer with revolving, preferably spring-loaded, paddles. Alternatively, a basket centrifuge may be employed. Spray-drying may be effected by a centrifugal atomizer, e.g. as described in Specification 365,342, [Group XXIX], or by passing the sludge through a jet and disintegrating by air under pressure. Sulphites, such as sodium sulphite or potassium metabisulphite, may be added between cooking and drying in such amount that the final concentration of sulphur dioxide in the powder does not exceed 100-150 p.p.m. Calcium salts, particularly calcium chloride, may be added up to .2 per cent, or more if milk is used, after mashing and before sieving. Common salt may also be added up to 5 per cent by weight in the dried product before drying. The pH of the reconstituted product should not exceed that of the fresh mashed potato, i.e. about 5.7-6. All apparatus used is made of, or coated with, a material such as stainless steel, to avoid contamination with iron.