Amorphisation and chain length reduction of cellulose affect its impact on the water distribution, dough rheology and loaf volume in bread making

The unfermentable nature of cellulose limits its physiological benefits as a dietary fibre. Recently, we drastically increased the fermentability of microcrystalline cellulose by human colon microbiota by reducing its crystallinity and polymer chain length (Thielemans et al., 2023). Here, the techno-functional impact of incorporating amorphised cellulose, depolymerised cellulose and amorphised depolymerised cellulose on bread making is investigated. Microcrystalline cellulose and its modified counterparts could be incorporated into bread at a 5 w/w% substitution level without significant volume losses. At a 20 w/w% substitution level, microcrystalline cellulose incorporation caused a loss of 36.4 ± 2.9% in bread loaf volume, while depolymerised celluloses reduced bread volume much less (16.2 ± 1.9%). In-depth characterisation of cellulose samples and 1H NMR and rheological measurements on bread dough revealed that the modified celluloses affected the water balance and gluten hydration in dough less than microcrystalline cellulose. These results complement insights on the importance of water-insoluble dietary fibre structure and hydration behaviour on bread (dough) quality.