Fermentation of pseudocereals quinoa, canihua, and amaranth to improve mineral accessibility through degradation of phytate

Abstract

BACKGROUND Pseudocereals are nutrient‐rich grains with high mineral content but also phytate content. Phytate is a mineral absorption inhibitor. The study's aim was to evaluate phytate degradation during spontaneous fermentation and during Lactobacillus plantarum 299v® fermentation of quinoa, canihua, and amaranth grains and flours. It also aimed to evaluate the accessibility of iron, zinc, and calcium and to estimate their bioavailability before and after the fermentation of flours with starter culture. Lactic acid, pH, phytate, and mineral content were analyzed during fermentation. RESULTS Higher phytate degradation was found during the fermentation of flours (64–93%) than during that of grains (12–51%). Results suggest that phytate degradation was mainly due to endogenous phytase activity in different pseudocereals rather than the phytase produced by added microorganisms. The addition of Lactobacillus plantarum 299v® resulted in a higher level of lactic acid (76.8–82.4 g kg−1 DM) during fermentation, and a relatively quicker reduction in pH to 4 than in spontaneous fermentation. Mineral accessibility was increased (1.7–4.6‐fold) and phytate : mineral molar ratios were reduced (1.5–4.2‐fold) in agreement with phytate degradation (1.8–4.2‐fold) in fermented flours. The reduced molar ratios were still above the threshold value for the improved estimated mineral bioavailability of mainly iron. CONCLUSION Fermentation proved to be effective for degrading phytate in pseudocereal flours, but less so in grains. Fermentation with Lactobacillus plantarum 299v® improved mineral accessibility and estimated bioavailability in flours. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Fermented Cereal-based Products: Nutritional Aspects, Possible Impact on Gut Microbiota and Health Implications

“…Furthermore, pseudo-cereals have also been reported to benefit from fermentation regarding the bioavailability of their minerals. Quinoa, canihua, and amaranth flours following fermentation exhibited improved accessibility of iron, calcium, and zinc compared to their raw counterparts [119].…”

Is There Such a Thing as “Anti-Nutrients”? A Narrative Review of Perceived Problematic Plant Compounds

“…Additional research by Castro-Alba et al demonstrated that inoculation of quinoa, amaranth, and canihua with L. plantarum 299v reduced phytate concentrations by 47–51%, 12–14%, and 25–27%, respectively. Accessibility of iron, zinc and calcium was also increased in the fermented flours [ 194 ]. Furthermore, L. plantarum species from supplements ( L. plantarum 299v), or from fermented vegetables ( L. plantarum spp.…”

Harnessing Microbes for Sustainable Development: Food Fermentation as a Tool for Improving the Nutritional Quality of Alternative Protein Sources

“…Because fermentation is a traditional way to process cereals for improvements in nutritional and sensory quality, it is also more and more frequently applied to process pseudocereal quinoa [30,[141][142][143][144][145]. Fermentations with L. plantarum strains have been found to increase Fe, Zn, and Ca solubility and to reduce phytic acid.…”

“…Fermentation of quinoa has often been combined with other food processing technologies, such as germination [145], milling [143], or roasting [144]. Typically, these pre-or post-treatments further decrease phytic acid and consequently increase mineral solubility; however, for instance, dry roasting after fermentation seems to be more efficient in aiding the phytic acid reduction and mineral availability, in comparison to dry roasting performed in advance [144].…”