(Adds report details, Unica comments, table) By Marcelo Teixeira SAO PAULO, Oct 24 (Reuters) - Brazilian mills increased the amount of cane used for ethanol production in the first half of October, and reduced sugar output, taking advantage of better pricing for the biofuel as sugar prices remain weak. Mills in the center-south region, the world's largest cane producing area, increased the amount of cane they used to produce ethanol to 56 percent in the first half of this month from 53 percent late in September and compared with 50 percent early in October last year, cane industry group Unica said on Tuesday. "The data collected in the period reveal a significant reversal on the production mix in favor of ethanol," Unica said in the report. Sugar production of 1.97 million tonnes in the first half of October was 12.2 percent lower than in the same period a year earlier, while ethanol output of 1.57 billion liters was 11.6 percent up. Mills crushed 32.41 million tonnes of cane in the first half of October versus 40.30 million tonnes in the second half of the previous month, Unica said. Total crush, sugar production and sugar mix were below market expectations for the period. INTL FCStone had expected a crush of 29 million tonnes, sugar production of 1.96 million tonnes and a sugar mix of 46 percent, while a Platts survey indicated a crush of 31.9 million tonnes, sugar output of 2.03 million tonnes and sugar mix of 44.5 percent. See below detailed figures from Unica's crop report for the first half of October (cane and sugar in million tonnes, ethanol in billion liters, total recoverable sugar-TRS in kg per tonne): BRAZIL'S CENTER-SOUTH - 1st HALF OF OCT (ANNUAL COMPARISON) 2016/17 2017/18 PCT CHANGE CANE CRUSH 32.19 32.41 0.68 SUGAR OUTPUT 2.25 1.97 -12.28 ETHANOL OUTPUT 1.41 1.57 11.62 TRS (kg/T) 148.15 146.36 -1.20 CANE TO SUGAR 49.62 pct 43.76 pct CANE TO ETHANOL 50.38 pct 56.24 pct BRAZIL'S CENTER-SOUTH CUMULATIVE DATA - 2016/17 VS 2017/18 2016/17 2017/18 PCT CHANGE CANE CRUSH 508.43 499.59 -1.74 SUGAR OUTPUT 30.13 31.21 3.57 ETHANOL OUTPUT 21.37 21.02 -1.66 TRS (kg/T) 133.75 136.84 2.32 CANE TO SUGAR 46.51 pct 47.92 pct CANE TO ETHANOL 53.49 pct 52.08 pct Source: Cane Industry Group Unica (Reporting by Marcelo Teixeira; Editing by Susan Thomas)