In determining pol reading of juices specific rotation plays major contribution and saccharim-eter gives the nett rotation of plane polarized light. The specific rotation of sucrose, glucose and fructose are +66.51, +52.74 at 20°C and -106 at 15°C respectively. But specific rotation of dextran is +199, have dextrorotatory property gives false pol reading when present in juices. Commercial sugar purity is 99.80 to 99.90 & is pure sucrose. In industry recovery is determined on the basis of sucrose production, therefore if false elevation in purity due to presence of dextrorotatory substances like dextran, gives the false recovery & deviation from actual. In estimation of daily recov-ery% cane with the helpofS.J.M. formula unknown loss is assumed. Assumption of unknown loss prior to determining other losses is incorrect. To avoid the discrepancy in evaluation author has suggested to evaluate rec.% cane daily by making pol balance & determine actual unknown loss.
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