Fourier‐transform infrared spectroscopy (FTIR) as a high‐throughput phenotyping tool for quantifying protein quality in pulse crops

Abstract

Fourier‐transform mid‐infrared (FT‐MIR) spectroscopy is a high‐throughput, cost‐effective method to quantify nutritional traits, such as total protein and sulfur‐containing amino acid (SAA) concentrations, in plant matter. This study used the spectroscopic technique FT‐MIR coupled with attenuated total internal reflectance sampling interface to develop multivariate models for total protein concentration in chickpea (Cicer arietinum L.), dry pea (Pisum sativum L.), and lentil (Lens culinaris Medik.), in addition to SAA concentration in lentil. Total nitrogen data from combustion analysis and SAA data from high‐performance liquid chromatography analysis following acid hydrolysis were used for model calibration and validation. Models for the total protein concentration of chickpea (calibration root mean square error [RMSE] = 0.093, R2 = 0.948, prediction RMSE = 0.10), dry pea (calibration RMSE = 0.096, R2 = 0.845, prediction RMSE = 0.093), and lentil (calibration RMSE = 0.13, R2 = 0.845, prediction RMSE = 0.11) utilized infrared regions associated with protein structures, namely amide bands A, I, and II. In sulfur‐related models for lentil total SAA (calibration RMSE = 0.014, R2 = 0.827, prediction RMSE = 0.022) and methionine (calibration RMSE = 0.0075, R2 = 0.815, prediction RMSE = 0.014) models utilized the C‐S and S‐CH3 stretching and bending bands. Study findings support the conclusion that FT‐MIR spectroscopy is a promising high‐throughput and cost‐effective phenotyping technique that will allow quantifying protein traits quickly and easily in pulse crops.

Fourier-Transform Mid-Infrared (FT-MIR) Spectroscopy as a High-Throughput Phenotyping Tool for Measuring Total Fatty Acids in Chickpea (Cicer arietinum L.) Flour

“…So, these models (Figures 4−6 Accordingly, our results support the implementation of FT-MIR as a high-throughput pipeline in breeding programs requiring minimal investments in labor and chemicals for TFA phenotyping in chickpeas. Further, this technique, combined with other FT-MIR approaches (i.e., protein analysis 13 ), can expand its applicability toward the chickpea-based food industry (i.e., in hummus production). Consequently, the nutritional quality of raw chickpea samples before processing can be assessed with high throughput to ensure the expected nutritional gain from the final product.…”

“…FT-MIR has been successfully applied to HTP of total protein in chickpeas, dry peas, lentils, and further sulfur-containing amino acids (SAA) in lentils. 13 Infrared (IR) spectroscopy operates between 14000 and 10 cm −1 and is sensitive to molecular vibrations, including stretching and bending modes. 14 The spectral regions in the IR window are near-IR (NIR) (12800−4000 cm −1 ), mid-IR (MIR) (4000−200 cm −1 ), and far-IR (FIR) (200−10 cm −1 ).…”

“…19 Because molecular functionalities are characteristics of bond stiffnesses and atomic masses, 18 the FT-MIR signals for nutritional traits should be universal, regardless of a sample's environment of origin. 13 Therefore, chemometric approaches based on multivariate calibrations such as partial least-squares (PLS) regression, multivariate regression (MLR), and artificial intelligence (AI) based neural networks (i.e., convoluted neural networks) can be applied to build strong predictive models (with supervised learning) targeting nutritional traits for HTP. 20−23 TAG molecules are typically abundant in chickpea fat (oil) and are IR active due to asymmetric geometries and nonzero dipole moments.…”

Organic dry pea (Pisum sativum L.): A sustainable alternative pulse-based protein for human health

“…Ultrapure water and deionized water (ddH 2 O) to a resistance of ≥18.2 MΩ×cm (PURELAB flex 2 system, ELGA LabWater North America, Woodridge, IL) were used. The AA analysis method is reported elsewhere [ 25 ] with modifications from the literature [ 26 , 27 ]. Samples (40 mg) of dry pea powder (particle size ≤ 0.5 mm) were weighed into glass culture tubes (16×125 mm, PTFE lined cap).…”

Effects of fine grinding on mid-infrared spectroscopic analysis of plant leaf nutrient content

“…All analytes except for boron, iron, and zinc were wellmodeled (average R 2 > 0.7), with higher R 2 values on ATR spectra. The 5 min level of fine grinding was found to be most optimal considering overall model performance and sample preparation time.Fourier-transform infrared (FTIR) spectroscopy is a popular technique in agricultural research due to its flexibility in various applications, including but not limited to quality analysis for livestock and crop products 1-3 , phenotyping [4][5][6] , and characterization of physical and chemical properties for soil and biological material [7][8][9][10] . In particular, FTIR spectroscopy can be used as an alternative or complementary method to more traditional chemical procedures for multiple nutrient analysis in plants and soil, which is important for determining plant nutrient uptake and managing fertilizer application 11 .…”