Exploring the dynamic water mobility and distribution in model systems of wheat noodles with different gluten-to-starch ratios based on LF-NMR

The changes in water status and water distribution in model systems of wheat noodles as a function of formulation and processing were studied. The composition was considered by using various gluten-to-starch ratios (0:100, 15:85, 30:70, 45:55, 55:45, 70:30, 85:15, 100:0 (w/w)), and the products resulting from four types of processing which covered the following processing variants: raw noodles (RNs), freeze-dried raw noodles (DRNs), cooked noodles (CNs), and freeze-dried cooked noodles (DCNs). The results showed that with increased gluten ratios, the moisture content increased in RNs, whereas it decreased in CNs. For the DRNs and DCNs, the moisture content had an increased trend along with increased gluten protein. The gluten protein had a higher water absorption capacity than unheated starch in RNs, whereas the heated starch could absorb more water than gluten protein in CNs. Additionally, the moisture mainly existed in RNs, CNs as weakly bound water, ranging from 60.4 to 81.3 %, 75.7–84.7 % and respectively. The moisture mainly existed in DRNs as strongly bound water (59.31–95.81 %), whereas existed in DCNs as weakly bound water (58.7–68.4 %). During the cooking and freeze-drying process, the weakly bound water was always affected most significantly in all formulated noodles.