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Despite being low in crude protein, on a fresh weight basis, given their overall contribution to the North American diet, potatoes contribute approximately 2%-4% of the population's protein intake. However, the quality of the protein remains ill-defined. To that end, Russet potatoes were secured and subjected to various cooking conditions (raw [control], boiled, baked, microwaved, and fried [3, 6, and 9 min]) to determine the impact of cooking method on protein quality, as determined by amino acid score (AAS) and indices of in vivo true fecal protein digestibility (TFPD%; rodent bioassay) and in vitro protein digestibility (pH-drop, pH-Stat, and simulated gastrointestinal digestion both static and dynamic). The AAS of raw Russet potatoes was 0.67 ± 0.01, with histidine being the limiting AA. Frying led to a significant reduction in the AAS, however, other cooking methods yielded similar results to the raw control. The TFPD% of raw potato was low (40.5% ± 3.9%) and was significantly enhanced to over 80% with all cooking methods. Similar patterns were observed with all in vitro measures, however, all methods yielded higher values for the raw control samples. Final protein digestibility-corrected AAS (PDCAAS; product of AAS and TFPD%) values ranged from 0.27 (raw) to a high of 0.57 (boiled), with cooked values being comparable to other plant-based protein sources, including grains, and some nuts and pulses. In vitro PDCAAS values followed similar trends. This study defined the protein quality of cooked Russet potatoes and provides data for use in defining the quality of total protein consumed in the North American diet., Competing Interests: The authors declare that they do not have any conflicts of interest., (© 2023 The Authors. Food Science & Nutrition published by Wiley Periodicals LLC.)

Chickpea is a widely produced pulse crop, but requires processing prior to human consumption. Protein bioavailability and amino acid quantity of chickpea flour can be altered by multiple factors including processing method. For this reason, the protein quality of processed chickpea flour was determined using in vivo and in vitro analyses for processed chickpeas. Processing differentially affected the protein digestibility-corrected amino acid score (PDCAAS) of chickpeas with extruded chickpea (83.8) having a higher PDCAAS score than both cooked (75.2) and baked (80.03). Interestingly, the digestible indispensable amino acid score (DIAAS) value of baked chickpea (0.84) was higher compared to both extruded (0.82) and cooked (0.78). The protein efficiency ratio, another measure of protein quality, was significantly higher for extruded chickpea than baked chickpea ( p  < .01). I n vivo and in vitro analysis of protein quality were well correlated ( R 2  = .9339). These results demonstrated that under certain circumstances in vitro methods could replace the use of animals to determine protein quality., Competing Interests: The authors declare no conflicts of interest with regard to the described research, the publication of results, or financial issues. Funding for the study was provided via Agriculture and Agri‐Food Canada Growing Forward 2—Pulse Science Cluster program funded this project. M.G.N was also supported by funds received from the Global Institute for Food Security, University of Saskatchewan, Saskatoon, SK. MGN and JDH designed and oversaw the experimental components of the study, and MGN prepared the first draft of the manuscript. GM, JN, AF, PA, AU, PF, and MGN conducted the technical aspects of the study. Chickpea varietal samples and data interpretation on varietal differences provided by BT., (© 2020 The Authors. Food Science & Nutrition published by Wiley Periodicals, Inc.)