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powder will not reconstitute so well, the solids tending to settle out rather than remain in homogeneous suspension. The cold break method has some merit in the manufacture of tomato juice, in which it often produces a better colour and flavour but it invariably has a tendency to cause separating out STRAINING From the pulper the material passes to a holding tank, thence to a series of strainers with perforated plates, reducing consecutively from 1mm holes to 0. 7mm and finally to 0. 4mm. This process removes the skin and seeds, amounting to 5 percent of the weight of the fruit. Strained pulp is then ransferred to storage tanks EVAPORATING The juice is concentrated under vacuum from 5 to 30 percent solids, as a preliminary stage to drying. A double-effect evaporator is normally used, h a finishing pan in the final stage. From here, the paste is transferred to a feed tank where it is constantly mechanically stirred SPRAY DRYING OF TOMATO POWDER The flow-sheet drawing Fig 8.1 shows an operation whereby the production of tomato powder is continuous and concurrent with the evaporation of the fresh pulp. In practice, however, some producers of tomato powder make their product out of season, and in the case of a plant in Portugal, which the author has visited, the company bought in most of their concentrate from a nearby tomato paste factory where there was a surplus, over and above what was contracted for export, as concentrate in 5kg cans The cans were delivered to thedrying plant in standard 5kg packaging, opened by a piston-type automatic can opener, which ejected the paste into the storage vat serving the dryer, at the same time crushing the empty ca and baling them for disposal. In this case the process commenced at Figure 19 on the Flow Sheet- Feed Tank for the Spray Dryer In this particular instance the concentrate was made by the hot break stem with concentration to 30-32 percent solids. Cold break pastes, concentrated to 36-38 percent concentration before drying, are sometimespowder will not reconstitute so well, the solids tending to settle out rather than remain in homogeneous suspension. The cold break method has some merit in the manufacture of tomato juice, in which it often produces a better colour and flavour but it invariably has a tendency to cause separating out. STRAINING From the pulper the material passes to a holding tank, thence to a series of strainers with perforated plates, reducing consecutively from 1 mm holes to 0.7mm and finally to 0.4mm. This process removes the skin and seeds, amounting to 5 percent of the weight of the fruit. Strained pulp is then transferred to storage tanks. EVAPORATING The juice is concentrated under vacuum from 5 to 30 percent solids, as a preliminary stage to drying. A double-effect evaporator is normally used, with a finishing pan in the final stage. From here, the paste is transferred to a feed tank where it is constantly mechanically stirred. SPRAY DRYING OF TOMATO POWDER The flow-sheet drawing Fig. 8.1 showsanoperation whereby the production of tomato powder is continuous and concurrent with the evaporation of the fresh pulp. In practice, however, some producers of tomato powder make their product out of season, and in the case of a plant in Portugal, which the author has visited, the company bought in most of their concentrate from a nearby tomato paste factory where there was a surplus, over and above what was contracted for export, as concentrate in 5kg cans. The cans were delivered to the drying plant in standard 5kg packaging, opened by a piston-type automatic can opener, which ejected the paste into the storage vat serving the dryer, at the same time crushing the empty cans and baling them for disposal. In this case the process commenced at Figure 19 on the Flow Sheet - Feed Tank for the Spray Dryer. In this particular instance the concentrate was made by the hot break system with concentration to 30-32 percent solids. Cold break pastes, concentrated to 36-38 percent concentration before drying, are sometimes used. 193
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