Rapid assessment of nutritional value indicators in Vigna unguiculata (L.) Walp. seed accessions from the VIR collection using NIR spectroscopy

Background. Cowpea (Vign a unguiculata (L.) Walp. is an important food and feed legume crop in countries with subtropical and tropical climates. Cowpea seeds have high nutritional value and contain large amounts of protein, starch, bioactive compounds, and iron, so they are often used in nutrition as a meat substitute and included in various diets. The development of calibration models for a rapid analysis of the main quality indicators in cowpea seeds based on NIR (near-infrared) spectroscopy will speed up the evaluation of accessions for nutritional value, reduce the cost of analysis, and help to preserve valuable breeding material. Materials and methods. Seeds of 39 cowpea (V. unguiculata) accessions with different seed coat colors from the collection of the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR) were analyzed. Quality indicators (protein, starch, and total anthocyanin content) were studied using analytical techniques accepted at VIR: the Kjeldahl method for protein content, the Evers method for starch, and spectrophotometry for total anthocyanins. Calibration models were calculated using the OPUS software developed for the MATRIX-I IR analyzer (Bruker Optics, Germany). Results and conclusion. The use of the developed calibration models for assessing the protein, total anthocyanin and starch content in cowpea seeds makes it possible to perform their mass analysis with high precision. This will accelerate the selection of source material for breeding cultivars with high seed quality indicators and make it more accurate.