Characterization of gluten-free bulk dough for laminated products

Abstract

The production of gluten-free (GF) laminated dough pieces is still a challenge in food industry. This work aims to evaluate changes in GF bulk dough characteristics as affected by the addition of hydrocolloids and the process of production of laminated products. Xanthan gum (XG), hydroxypropyl methylcellulose (HPMC) and psyllium (P) were added at 2.5 and 5% in GF dough made with rice and soy flour and cassava starch. Protein fractions were extracted, quantified and analyzed by electrophoresis. Rheology was evaluated by a creep and recovery test and proton mobility was explored by nuclear magnetic resonance. Tests were done on samples before and after the refrigerated rest time to assess the impact of that production step. Extractability of native proteins increased with lower doses of additives, while higher doses reduced it. The opposite behavior was observed on extractability of noncovalent proteins. Under stress, XG (J0: 7.7·10–6 and 4.9·10–6 Pa−1; J1: 7.3·10–6 and 4.9·10–6 Pa−1) and HPMC samples (J0: 7.0·10–6 and 6.5 10–6 Pa−1; J1: 8.2·10–6 and 8.6·10–6 Pa−1) showed lower instantaneous and viscoelastic compliance than control sample (J0: 9.8·10–6 Pa−1; J1: 10.5 10–6 Pa−1), while P had higher values (J0: 10.4·10–6 and 9.8·10–6 Pa−1; J1: 12.5·10–6 and 12.5·10–6 Pa−1). Additives promoted more viscous dough relaxation. After the refrigerated rest time, XG-2.5% elastic recover enhanced, while HPMC showed the opposite. XG decreased water proton mobility and P increased it. The refrigerated rest time enhanced water structuration.