RT info:eu-repo/semantics/article
T1 Inactivation of Endogenous Rice Flour β-Glucanase by Microwave Radiation and Impact on Physico-chemical Properties of the Treated Flour
A1 Pérez Quirce, Sandra
A1 Ronda Balbás, María Felicidad
A1 Melendre Frías, María del Carmen
A1 Lazaridou, Athina
A1 Biliaderis, Costas G.
K1 β-Glucanase inactivation
K1 microwave treatment
K1 pasting properties
K1 rice flour
K1 thermal properties
K1 X-Ray diffractometry
AB The apparent reduction of β-glucan (BG) molecular weight in rice based gluten-free (GF) breads fortified with cereal BG concentrates reveals the presence of β-glucanase activity in rice flour. Inactivation of endogenous β-glucanase in rice flour thus seems to be necessary step when developing GF breads enriched with BG of high molecular-weight. The aim of this work was to study the thermal inactivation of endogenous β-glucanase in rice flour by means of microwave (MW) processing; rice flours preconditioned at four different moisture levels (13%, 16%, 19%, 25%) were treated by MW radiation at 900 W and five MW treatment times (ranging from 40s to 8 min, applied stepwise at 20s intervals). The effects of microwaves on starch crystallinity, pasting and thermal properties of MW-treated rice flours were also explored. The β-glucanase activity in rice flours was assessed by the rate of decrease in specific viscosity of a dilute solution of a purified β-glucan preparation, upon addition of flour extracts. MW proved to be a useful alternative for thermal inactivation of endogenous β-glucanase in rice flours when applied to moistened samples. The inactivation process followed a first order kinetic response and the apparent rate constant of thermal inactivation increased exponentially with the moisture content of the flour, M, according to the equation 0.0146·exp (0.212·M)(R2 = 0.97). The MW time required for complete β-glucanase inactivation was only 4 min when the initial flour moisture increased to 25%. Following MW treatment, the starch crystallinity was unaffected (p>0.05) and the side effects of the treatment on flour pasting and thermal properties were rather negligible.
PB Springer
SN 1935-5130
YR 2016
FD 2016
LK http://uvadoc.uva.es/handle/10324/24270
UL http://uvadoc.uva.es/handle/10324/24270
LA eng
NO Food and Bioprocess Technology. (2016) Vol 9 (9), p. 1562-1573
NO Producción Científica
DS UVaDOC
RD 16-jul-2024