Infrared Spectroscopy‐Based Metabolomic Analysis for the Detection of Preharvest Sprouting in Grain

Abstract

Cereal Chem. 93(5):444-449Preharvest sprouting of grains causes significant losses to growers and buyers. The problem occurs throughout the world, and economic losses can be millions of dollars. Visual assessment of germination is ineffective because even grains showing no external signs (e.g., having a visible shoot) may still have germinated sufficiently so that it is no longer possible for high-quality products to be made from them. Current procedures to determine whether a grain has germinated are based around measuring enzyme or starch levels. However, despite protracted efforts to develop enhanced ways to measure germination over the last 50 years, there are currently no sufficiently accurate or reliable approaches available. The present work assesses the potential for infrared spectroscopy-based metabolomic profiling to assess the germination of barley and wheat.The results indicate that mid-and near-infrared spectroscopy are able to determine if the grain has germinated and give an indication of how long the germination process has been occurring. Both techniques are already well established in the grain industry and have the potential to form the basis of a simple, fast dockside test that would allow segregation of sound and mildly sprouted grain. † Corresponding author. Phone: +61 (0)3 9925 2632.

Monitoring the sprouting process of wheat by non-conventional approaches

“…Near Infrared Spectroscopy has proved to be successful in determining the authenticity and traceability of cereals (Cozzolino, 2014). Moreover, Infrared spectroscopy has been applied on flour to detect pre-harvest sprouting and the time of its occurrence in wheat and barley (Burke et al, 2016). Burke et al (2016) obtained good Partial Least Squares models for FT-IR data (RCV 2 of 0.75), but poor validation results by FT-NIR modelling as high overfitting occurred.…”

“…Moreover, Infrared spectroscopy has been applied on flour to detect pre-harvest sprouting and the time of its occurrence in wheat and barley (Burke et al, 2016). Burke et al (2016) obtained good Partial Least Squares models for FT-IR data (RCV 2 of 0.75), but poor validation results by FT-NIR modelling as high overfitting occurred. As for the development of individual kernels, a review by Fox & Manley (2014) described in detail how Near Infrared Spectroscopy is used to evaluate the physical quality and chemical traits of cereal grains.…”

Unraveling Key Metabolomic Alterations in Wheat Embryos Derived from Freshly Harvested and Water-Imbibed Seeds of Two Wheat Cultivars with Contrasting Dormancy Status

“…Although the effects of PHS conditions on wheat have been the subject of intense research at the levels of quantitative genetics, physiology, molecular biology, and genomics, no detailed metabolomics-based study has been performed yet on wheat embryos related to PHS and/or seed dormancy ( Zanetti et al, 2000 ; Kulwal et al, 2004 ; Carvalho and Beleia, 2015 ; Shu et al, 2015 ). Recent studies have started to emerge on infrared spectroscopy-based metabolomic profiling, which assesses the length of the germination process in barley and wheat ( Burke et al, 2016 ). A recent excellent report recommended using the near-infrared spectroscopy to the grain industry to detect instances of germination in cereal seeds at a very early stage where symptoms of germination are not visible to human eyes, and thus barely sprouted grains can be noticed ( Jones, 2017 ).…”

Assessing pre-harvest sprouting in cereals using near-infrared spectroscopy-based metabolomics

“…This most likely means that the underlying model requires a greater number of samples in order for it to provide useful results. 4 Additionally, as we used first and second derivative spectra, the corresponding loadings plots are not very informative.…”