A magnetic stirrer bar was added to each tube containing the residues and the tubes were placed in a test tube rack in an ice-water bath over a magnetic stirrer. With the stirrer turned on, 3 m LKOH 2 mol L1 was added to each tube and the slurry was stirredfor 20 min. Each tube was, then, treated with 10 mL 1.2 mol L1 sodium acetate buffer (pH¼3.8). Immediately, 0.1 mL amyloglu-cosidase was added (3200 U mL1NaAc/HAc buffer, pH¼4.75),with vigorous mixing, the magnetic stirrer bars were removed andthe magnetic stir was stopped. The pH was verified and should bebetween 4.7 and 5.0. Tubes were capped and incubated in shaker-bath at 50C for 30 min.After incubation, the tubes had their volume completed to 20 mL with Milli -Q water and were centrifuged at 554.4 g for 10 min.Glucose was quantified on the supernatants with GOD/POD/ABTS mixture (Bergmeyer & Bernet,1974). If samples contained more than10 g/100 g of RS, the solution, after incubation at 50C, was quanti-tatively transferred to a 100 mL volumetric flask and diluted tovolume with Milli-Q water and an aliquot of 20 mL of this solutionwas centrifuged and analyzed as described for other samples