This method has been devised by Lazar, Barta and Smith of the Western Regional Research Laboratory, US Department of Agriculture, Albany, California, where promising tests have been made on apricots, peaches, pears and raisins. Apricots, particularly, responded well to this method, the dried fruit retaining a bright translucent colour instead of the dull red-orange of the sun dried product. The best results were obtained by reducing the blanching temperature to under 100"C at the 50 percent weight reduction point the primary drying. Such a system was also effective with raisins, which suffer from splitting of skins with a 100Cblanch, and this was eliminated by a temperature reduction to 92"C. Sulphating The use of sulphur houses was ordinarily, but not necessarily exclusively associated with sun drying methods, and sulphite dipping with mechanical drying A sulphuring house is always erected away from the main factory building. The fruit is spread on trays which are racked on trolleys in a simila manner to that used in tunnel drying. The trolleys are pushed into the lphuring shed, which is fitted with a sulphur burner at the bottom end with adequate venting to atmosphere, either by natural draught or by fan, hrough the roof 2 to 3kg of sulphur are burnt for each ton of fruit treated, and the exposure time is varied according to the absorption characteristics of the fruit. The latter must be tested regularly but, as a guide, the concentration of SO2 in the sulphur shed should be maintained at about 2 percent. Residual SO, in the dried fruit will range from 1500 to 2000ppm An exception to the use of sulphite can be exercised with Thompson Seedless grapes for the production of 'natural raisins instead of the more golden-bleach raisins which contain levels of SO, up to 2000p and are mostly artificially dried Processing All the fruit processing described in this chapter except currants and peaches relates to artificial drying in either Conveyor Band, Tunnel or Stove Dryers, and whilst the Dry-Blanch-Dry method is prescribed for Apricotson the basis ofthe authors trials, it could equally be used for Pears and Peaches, Apple Rings and natural Raisins Apples(Rings and Flakes) (1) Flow Sheet Feed to LiThis method has been devised by Lazar, Barta and Smith of the Western Regional Research Laboratory, US Department of Agriculture, Albany, California, where promising tests have been made on apricots, peaches, pears and raisins. Apricots, particularly, responded well to this method, the dried fruit retaining a bright translucent colour instead of the dull red-orange of the sun dried product. The best results were obtained by reducing the blanching temperature to under 100°C at the 50 percent weight reduction point the primary drying. Such a system was also effective with raisins, whichsuffer fromsplittingof skinswitha 100°C blanch,and this was eliminated by a temperature reduction to 92°C. Sulphiting The use of sulphur houses was ordinarily, but not necessarily, exclusively associated with sun drying methods, and sulphite dipping with mechanical drying. A sulphuring house is always erected away from the main factory building. The fruit is spread on trays which are racked on trolleys in a similar manner to that used in tunnel drying. The trolleys are pushed into the sulphuring shed, which is fitted with a sulphur burner at the bottom end, with adequate venting to atmosphere, either by natural draught or by fan, through the roof. 2 to 3kg of sulphur are burnt for each ton of fruit treated, and the exposure time is varied according to the absorption characteristics of the fruit. The latter must be tested regularly but, as a guide, the concentration of SO, in thesulphur shed should be maintained at about 2 percent. Residual SO, in the dried fruit will range from 1500 to 2000ppm. An exception to the use of sulphite can be exercised with Thompson Seedless grapes for the production of 'natural' raisins instead of the more common 'golden-bleach' raisins which contain levels of SO, up to 2000ppm and are mostly artificially dried. Processing All the fruit processing described in this chapter except currants and peaches relates to artificial drying in either Conveyor Band, Tunnel or Stove Dryers,and whilst the Dry-Blanch-Dry method is prescribed for Apricots on the basis of the author's trials, it could equally be used for Pears and Peaches, Apple Rings and natural Raisins. Apples (Rings and Flakes) (1) Flow Sheet Feed to Line I70