Impact of konjac glucomannan with varied deacetylation degrees on plant-based meat analogue: Study on the gel properties, digestibility, and microstructure

Polysaccharides are widely used to improve the quality of plant-based meat analogue (PMA). In this study, four kinds of konjac glucomannan (KG) with different deacetylation degrees (DD) were prepared, namely KG 1 (native KG, DD = 0.00 %), KG 2 (DD = 41.40 %), KG 3 (DD = 80.01 %) and KG 4 (DD = 89.07 %), and their effects on the quality of PMA were studied. Results manifested that KG 3 improved the hardness (from 3017.16 g to 3307.16 g) and protein digestibility (from 49.65 % to 53.01 %) of PMA without reducing the P 21 , KG 2 and KG 4 were less effective than KG 3 , while KG 1 led to a significant decline in the hardness and protein digestibility of PMA. The rheological properties and intermolecular force analysis showed that the partially deacetylated KG was more conducive to improving the G' of the protein system during heating and the proportion of covalent bonds in PMA. These findings suggested that partially deacetylated KG was more promising than native or highly deacetylated KG in PMA. Furthermore, scanning electron microscopy revealed that the morphology of KG gradually changed from fine filaments, to coarse filaments, short filaments and granules as DD increased. This study provides a theoretical basis for the application of partially deacetylated KG in PMA.