Utilization of Sweet Lupin Hull Fibers in Formulating Novel Functional Bread

Document Type : Original Article

Abstract

A good correlation between fibers consumption and the reduction of coronary heart-related diseases and diabetes
incidence has become evident. However, fibers intake is commonly lower than recommended. In consequence, the
development of foods with high fiber content should be desirable. The aim of this paper is to investigate the possibility
of using substituting wheat flour (WF) with 5, 10 and 15% sweet lupin hull fibers (SLHF) in formulating novel functional
bread. The SLHF showed higher levels of ash, crude fat, total phenolic, flavonols and dietary fibers than the WF.
The SLHF increased the water absorption and dough development time. Regarding dough stability, it appears that 5%
SLHF exhibited higher stability and resistance to mechanical mixing values than the control, while it decreased as the
substitute level increased from 10% to 15%. A linear viscoelastic behaviour of module at the range of 10–4≤γ≤ 10–3
was found. The storage modulus (G΄) was greater than the loss modulus (G´´). The dough handling was not affected
at any levels of supplementation with SLHF and dough surface of the wheat dough and its blends with 5, 10 and 15 %
SLHF were classified as “normal”. The crust of the control was lighter and less yellow than any of the other samples.
For crumb colour, as the level of SLHF increased, the a* and b* values increased, indicating that a redder and more
yellow crumb was obtained as a result of SLHF substitution. Supplementation WF with SLHF at level of 5 and 10 %
gives parameter values at least as good as the control sample and 15 % produces acceptable bread in terms of weight,
volume, crumb structure and colour. In addition, sensory evaluation showed that panelists judged these fiber-enriched
breads as acceptable. Therefore, their use allows an increase of the daily intake of fibers without promoting negative
effects on the rheological properties of doughs or quality and overall acceptability of the resulting breads. This study
indicates that substituting wheat flour (WF) with SLHF at levels from 5 to 15% can be used in bread making in order
to fortify the diet.

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