Effect of fermentation and dry roasting on the nutritional quality and sensory attributes of quinoa

Abstract

BackgroundQuinoa is a pseudocereal with relatively high content of proteins and minerals that also contains mineral inhibitors such as phytate. The aim of the present study was to evaluate lactic acid fermentation and dry roasting on the nutritional quality and sensory attributes of quinoa. Various processes were evaluated, and quinoa grains were dry‐roasted, milled, and fermented, either with or without the addition of wheat phytase or activated quinoa phytase (added as back‐slop starter), for 10 hr. In other processes, raw quinoa flour was fermented for 10 hr or 4 hr and dry‐roasted. Hedonic sensory evaluation was then performed to evaluate the acceptability of the fermented flours prepared as porridges.ResultsThe combined dry roasting and fermentation processes significantly (p < .05) degraded phytate between 30% and 73% from initial content. The most effective process was fermentation of raw quinoa flour followed by dry roasting, which improved the estimated zinc and iron bioavailability. Particularly, estimated zinc bioavailability improved from low (Phy:Zn 25.4, Phy·Zn:Ca 295) to moderate (Phy:Zn 7.14, Phy·Zn:Ca 81.5). Phytate degradation was mainly attributed to the activation of endogenous phytase during fermentation. Dry roasting was effective in improving the sensory attributes of the fermented quinoa flour. Porridge made with raw quinoa flour fermented for 4 hr and dry‐roasted was more favorable to overall acceptability than that which was fermented for 10 hr and dry‐roasted.ConclusionFermentation of quinoa flour for 4 hr followed by dry roasting was successful in improving both nutritional and sensory attributes of the final product.

Enhancing Micronutrients Bioavailability through Fermentation of Plant-Based Foods: A Concise Review

“…Furthermore, the highest phytic acid reduction (98%) was observed after fermentation of the germinated flour [82]. Moreover, Castro-Alba et al [83] recently reported that fermentation (4 or 10 h, at 30 • C) of milled quinoa seeds using L. plantarum 299v reduced the phytic acid significantly and improved the bioavailability of minerals such as Ca, Fe, and Zn [83]. In another previous study, the effect of natural sourdough fermentation of wheat showed a much better improvement of copper and magnesium absorption in comparison to nonfermented wheat flour, using male Wistar rats.…”

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

“…For example, in a study surveying the effect of fermentation (16−18 h, 30 • C) with commercial L. plantarum starter, it was observed that the amount of soluble Fe in quinoa suspension was significantly increased in comparison to nonfermented suspension, while the content of phytic acid was significantly decreased [145]. Furthermore, fermentation (4, 10, or 48 h, 30 • C) of milled quinoa seeds with L. plantarum 299v has shown good efficiency in reducing phytic acid and a moderate capability to improve estimated Zn, Fe, and Ca availability [144]. These improvements were apparent already after 4 h [144].…”

“…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.…”

“…Furthermore, fermentation (4, 10, or 48 h, 30 • C) of milled quinoa seeds with L. plantarum 299v has shown good efficiency in reducing phytic acid and a moderate capability to improve estimated Zn, Fe, and Ca availability [144]. These improvements were apparent already after 4 h [144]. Depending on the bacterial strains present in mixed LAB cultures (Leuconostoc mesenteroides subsp.…”

“…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]. It has been suggested that the pre-and post-treatments may help to either activate or inactivate endogenous phytases [144,145].…”