Effect on protein content and digestibility of traditional bread by incorporating Arthrospira platensis

Abstract

Since the world population is expected to reach 9.8 billion by 2050, a global demand for alternative proteins to traditional ones is expected. Alternative plant-based proteins are experiencing significant global demand as they offer similar characteristics, at a relatively more affordable cost than animal proteins. In recent years, the industrial production of microalgae biomass has received attention attributable to its rich content of quality proteins. On the other hand, due to their low carbon footprint, wastewater treatment benefits and carbon credit from industrial CO2 conversion, microalgae-based proteins have the potential to provide ecologic benefits. In this sense, the study of new species of protein-rich microalgae is an area of ongoing research. Thus, the main objective of the present study was to culture and characterize microalgal isolates of Arthrospira platensis from the Yaragui Lagoon of the Paraguayan Chaco. Nitrogen protein was studied by Kjeldahl method and the same technique was applied to obtain the non-protein nitrogen, but after treatment of the sample with trichloroacetic acid to remove proteins. The hydrosoluble protein content was measured by the Lowry method after freezing and thawing followed by sonication, and was compared with the Kjeldahl method. The nitrogen-to-protein conversion factor for biomass experimentally obtained was 6.2508 for nitrogen measured by Kjeldahl. Protein total content was around 67% and the hydrosoluble fraction corresponds to 66% of it. The proximate composition, the protein profile, the molecular structure and functional groups were also studied. Finally, the addition of Arthrospira to bread showed that nutritional quality was improved and the level of protein digestibility achieved was satisfactory. Thus, the results suggest that using A. platensis from the Yaragui Lagoon of the Paraguayan Chaco to make rich protein products provides a viable alternative for human consumption.