Efeito de farelo de arroz tratado termicamente na vida de prateleira de biscoito tipo amanteigado / Effect of heat-treated rice bran on the shelf-life of butter biscuits

ABSTRACT

Rice bran was submitted to two heat treatments. In the first treatment, bran was heated in an oven at 105§C for 20 minutes and, in the second treatment, it was heated in a steam autoclave with a pressure of 78456 Pa at 125§C for 20 minutes. The two heated brans were mixed wheat flour at three different levels (O, 10 AND 20 per cent) and these blends were used for the production of biscuits. The biscuit acidity increased with the presence of rice bran in the flour. Biscuits produced with oven-heated bran showed the highest acidity and, the longer the storage time the higher the acidity. It was observed that biscuits which had rice bran in their formulation presented a higher moisture content, which did not vary with storage possibly due to the packaging. Members of the taste panel were able to perceive differences between biscuits which contained bran produced by the two different heat treatments. Biscuits produced with the oven heated bran were darker. Also, they presented unpleasant smell and taste. The other biscuits, produced with the other formulations, obtained intermediate scores in relation to the ones produced just with wheat flour. The results show that the use of rice bran for biscuits-making is practicable and that it could be easily used in biscuits commercial production