Effect of cooking conditions on chickpea flour functionality and its protein physicochemical properties.

Chickpea is an important food legume that usually undergoes various processing treatments to enhance nutritional value and functional properties. This study aimed to investigate the effects of different cooking conditions on physicochemical, structural, and functional properties of chickpea, especially its protein macromolecules. Kabuli chickpea seeds were processed by water cooking at different temperatures (63, 79, 88, and 96°C), followed by evaluating flour solubility, water-holding capacity (WHC), pasting property, as well as the total protein profile and fractionated protein distributions. Cooking treatments significantly decreased flour solubility (from 39.45 to 25.21 g/100 g flour) and pasting viscosity (peak and final viscosities, from 1081 to 300.5 cP and 1323 to 532 cP, respectively), while increasing WHC (from 0.862 to 1.144 g H2O/g flour) of chickpea flour (p < 0.05). These behaviors were enhanced by increasing cooking temperature. Meanwhile, cooking induced a significant change of chickpea proteins, modifying the albumin- and globulin-like fractions of chickpea protein to display glutelin-like behavior. The current study provides potential approaches for manipulating chickpea flour functionalities (e.g., solubility, viscosity, and WHC) to address the process and product challenges and favor product innovation.

Laboratory Screening Protocol to Identify Novel Oleaginous Yeasts.

Oleaginous microbes, which contain over 20% intracellular lipid, predominantly triacylglycerols (TG), by dry weight, have been discovered to have high oil content by many different protocols, ranging from simple staining to more complex chromatographic methods. In our laboratory, a methodical process was implemented to identify high oil yeasts, designed to minimize labor while optimizing success in identifying high oil strains among thousands of candidates. First, criteria were developed to select candidate yeast strains for analysis. These included observation of buoyancy of the yeast cell mass in 20% glycerol, and phylogenetic placement near known oleaginous species. A low-labor, semiquantitative Nile red staining protocol was implemented to screen numerous yeast cultures for high oil content in 96-well plates. Then, promising candidates were selected for more quantitative analysis. A more labor-intensive and quantitative gravimetric assay was implemented that gave consistent values for intracellular oil content for a broad range of yeast species. Finally, an LC-MS protocol was utilized to quantify and identify yeast triacylglycerols. This progressive approach was successful in identifying 30 new oleaginous yeast species, out of over 1000 species represented in the Phaff Yeast Culture Collection.