Sensory Characteristics and Nutritional Quality of Food Products Made with a Biofortified and Lectin Free Common Bean (Phaseolus vulgaris L.) Flour

Abstract

Common beans (Phaseolus vulgaris L.) are an important source of nutrients with beneficial effects on human health. However, they contain lectins, that limit the direct use of flour in food preparations without thermal treatment, and phytic acid, that reduces mineral cation bioavailability. The objectives of this research were: to obtain biofortified snacks and a cream using an untreated common bean flour devoid of active lectins (lec^-) and with reduced content of phytic acid (lpa) and to evaluate the sensorial appreciation for these products. The main results of the present work were: the products with the lpa lec^- flour did not retain residual hemagglutinating activity due to lectins; they showed higher residual α-amylase inhibitor activity (from 2.2 to 135 times), reduced in vitro predicted glycemic index (about 5 units reduction) and increased iron bioavailability compared to the products with wild type flour; products with common bean flour were less appreciated than the reference ones without this flour, but the presence of an intense umami taste can be a positive attribute. Results confirmed that the use of the lpa lec^- flour has important advantages in the preparation of safe and nutritionally improved products, and provide useful information to identify target consumers, such as children and elderly people.

Keywords: biofortification; lectins; nutritional enhancement; phytic acid; predicted glycemic index; sensory analysis; temporal dominance sensation; α-amylase inhibitor.

Figure 1

Samples used for the sensorial evaluation. (A) Cracker R, (B) Cracker 1, (C) Cracker 2, (D) Biscuit 1R, (E) Biscuit 1, (F) Biscuit 2R, (G) Biscuit 2, (H) Cream R, (I) Bean Cream. All R samples were reference without common bean flour, while the samples Crackers 1 and 2, Biscuits 1 and 2 and Bean Cream contained 26, 38, 29, 14 and 9% of common bean flour, respectively.

Figure 2

Hemagglutinating activity of bean-based products and bean flour extracts. Serial dilutions of equal amounts of bean-based products or seed flour extracts obtained from two different genotypes (wt and lpa lec⁻) were compared. Blue circles indicate sample dilutions able to agglutinate red blood cells. The percentage of bean flour in biscuits was adjusted based on the weight of defatted samples (in defatted biscuits 1 bean flour was 29.4%).

Figure 3

Ferritin production after incubation of Caco-2 cells with wild type (wt) flour, lpa lec⁻ flour, wt Biscuit 1 or lpa lec⁻ Biscuit1 samples. Samples (n = 10) were statistically evaluated by Mann-Witney test. ** p = 0.085.

Figure 4

Sensorial profiles of crackers with [Cracker 1 (26%); Cracker 2 (38%)] and without [Cracker R] bean flour. Data analyzed by ANOVA and post hoc test (Tukey’s HSD); *, **, *** indicate significant differences between the tested products at p < 0.1, p < 0.5 and p < 0.01, respectively.

Figure 5

Temporal dominance of sensations (TDS) flavor of (A) Crackers R (reference, without common bean flour), (B) Crackers 1 (with 26% common bean flour) and (C) Crackers 2 (with 38% common bean flour).

Figure 6

Sensorial profile of shortbread biscuits without (Biscuits 1R, reference) and with common bean flour (Biscuit 1). Data analyzed by ANOVA and post hoc test (Tukey’s HSD); *, **, *** indicate significant differences between the tested products at p < 0.1, p < 0.5 and p < 0.01, respectively.

Figure 7

Temporal dominance of sensations (TDS) of (A) Biscuits 1R (reference, without common bean flour) and (B) Biscuit 1 (with 29% common bean flour).

Figure 8

Sensorial profiles of type 2 Biscuits, without (2R) and with common bean flour (2). Data analyzed by ANOVA and post hoc test (Tukey’s HSD); *, **, *** indicate significant differences between the tested products at p < 0.1, p < 0.5 and p < 0.01, respectively.

Figure 9

Temporal dominance of sensations (TDS) of (A) Biscuits 2R (reference, without common bean flour) and (B) Biscuit 2 (with 14% common bean flour).

Figure 10

Sensorial profile of cream without (Cream R, reference) and with common bean flour (Bean Cream). Data analyzed by ANOVA and post hoc test (Tukey’s HSD; *, **, *** indicate significant differences between the tested products at p < 0.1, p < 0.5 and p < 0.01, respectively.

Figure 11

Temporal dominance of sensations (TDS) of (A) Cream R (reference, without common bean flour) and (B) Bean Cream (with 9% common bean flour).