Small-Seeded Legumes as a Novel Food Source. Variation of Nutritional, Mineral and Phytochemical Profiles in the Chain: Raw Seeds-Sprouted Seeds-Microgreens

Abstract

Growing public concerns about health haves prompted the search for novel food sources. The study is focused on the seeds, sprouted seeds and microgreens of <i>Trifolium pratense, T. medium</i>, <i>Medicago sativa</i>, <i>M. lupulina, Onobrychis viciifolia, Astragalus glycyphyllos</i> and <i>A. cicer</i> species as a potential source of value-added food ingredientsr. The samples were analysed for nutritional (wet chemistry, standard methods) and mineral (atomic absorption spectroscopy, UV-Vis spectrophotometry) profiles, isoflavones (ultra-performance liquid with diode array detector ⁻UPLC-DAD), coumestrol (UPLC-DAD), condensed tannins (CT) (vanillin-H₂SO₄ assay) and triterpene saponins (UPLC with triple-stage quadrupole MS). In our study, each species displayed high, but species-dependent nutritional, mineral and phytochemical value. All counterparts of legumes were mineral and protein rich. <i>A. glycyphyllos</i> samples, especially seeds, were abundant in iron. <i>Trifolium</i> spp. were found to be important sources of isoflavones, <i>Medicago</i> spp. of coumestrol and saponins, and <i>O. viciifolia</i> of CT. The protein and phytochemical contents increased and total carbohydrates decreased from seeds to microgreens.Our findings proved for the first time that seeds, sprouted seeds, and especially microgreens of small-seeded legumes are promising new sources of ingredients for fortification of staple foods with bioactive compounds, minerals and nutrients.