Chickpea flour (CF)-based muffin formulations were made with CF alone and with added biopolymers [whey protein (WP), xanthan gum (XG) and inulin (INL)] to evaluate their suitability to be a wheat flour (WF) substitute in muffins. Structural characteristics of the batters and muffins were studied by means of rheometry, microscopy, physicochemical properties, and texture and sensory analysis. Partial replacement of CF with XG, alone (at 0.5 and 1%) or blended with either WP or INL, significantly increased the batter viscoelasticity as denser matrices developed; moreover, the muffins with XG added at 1% had similar hardness to wheat gluten muffins. The replacement of WF decreased the springiness, cohesiveness, chewiness, resilience and specific volume of the muffin. However, baked muffins with added XG also showed higher sensory sponginess and moisture associated with numerous air bubbles in the batter and were perceived to be easier to swallow and to have better general appearance.

Thermorheological changes in high hydrostatic pressure (HHP)-treated chickpea flour (CF) slurries were studied as a function of pressure level (0

The effect on rheological properties of muffin batter of replacing wheat flour (WF) with chickpea flour (CF) was studied by using viscoelastic and steady-state shear tests to characterize the physical structure and predict both processing and batter performances. CF was used to replace WF in the batter partially (25, 50, 75% w/w) or totally (100% w/w, i.e., CF-based gluten-free muffin batter), and compared with a control made only with wheat (100% WF batter). Viscoelasticity and rebuild time decreased significantly with the increase in the percentage of WF replacement. Gluten-free muffin batter had the highest viscosity after shearing reflecting a trend toward a dilatant flow behavior associated with higher intermolecular aggregation interactions due to higher protein content. Rheological properties of the batters are dominated by the starch and protein contents present in the formulations. Replacement of WF by CF also increased the number of air bubbles which were smaller. PRACTICAL APPLICATIONSGluten-free muffins should resemble those made from WF, overcoming problems of quality defects and low nutritional value. Potential for use of CF in gluten-free muffins is related to its high protein content, playing a healthy and functional role. Formulation of gluten-reduced and gluten-free muffins involves studying batter rheology and resulting baked product characteristics. Various CF-based muffin batters were formulated and rheologically characterized under small and large deformations to attain insights of structural status and mechanical behavior. Higher WF batter viscoelasticity is related to higher starch content, whereas higher CF batter viscosity after shearing correlated well with higher protein content. CF with starch content adjusted to the level of WF could decrease differences in rheological properties of batters. CF helped to incorporate air into the batter, which is essential for achieving appropriate final volume and spongy texture.

Although biofilm formation is a very effective mechanism to sustain bacterial life, it is detrimental in medical and industrial sectors. Current strategies to control biofilm proliferation are typically based on biocides, which exhibit a negative environmental impact. In the search for environmentally friendly solutions, nanotechnology opens the possibility to control the interaction between biological systems and colonized surfaces by introducing nanostructured coatings that have the potential to affect bacterial adhesion by modifying surface properties at the same scale. In this work, we present a study on the performance of graphene and hexagonal boron nitride coatings (h-BN) to reduce biofilm formation. In contraposition to planktonic state, we focused on evaluating the efficiency of graphene and h-BN at the irreversible stage of biofilm formation, where most of the biocide solutions have a poor performance. A wild Enterobacter cloacae strain was isolated, from fouling found in a natural environment, and used in these experiments. According to our results, graphene and h-BN coatings modify surface energy and electrostatic interactions with biological systems. This nanoscale modification determines a significant reduction in biofilm formation at its irreversible stage. No bactericidal effects were found, suggesting both coatings offer a biocompatible solution for biofilm and fouling control in a wide range of applications.

In this work we present a study on the performance of CVD (chemical vapor deposition) graphene coatings grown and transferred on Ni as protection barriers under two scenarios that lead to unwanted metal ion release, microbial corrosion and allergy test conditions. These phenomena have a strong impact in different fields considering nickel (or its alloys) is one of the most widely used metals in industrial and consumer products. Microbial corrosion costs represent fractions of national gross product in different developed countries, whereas Ni allergy is one of the most prevalent allergic conditions in the western world, affecting around 10% of the population. We found that grown graphene coatings act as a protective membrane in biological environments that decreases microbial corrosion of Ni and reduces release of Ni2+ ions (source of Ni allergic contact hypersensitivity) when in contact with sweat. This performance seems not to be connected to the strong orbital hybridization that Ni and graphene interface present, indicating electron transfer might not be playing a main role in the robust response of this nanostructured system. The observed protection from biological environment can be understood in terms of graphene impermeability to transfer Ni2+ ions, which is enhanced for few layers of graphene grown on Ni. We expect our work will provide a new route for application of graphene as a protection coating for metals in biological environments, where current strategies have shown short-term efficiency and have raised health concerns.