A recent upgrade to the optics configuration of a thermal source FTIR microscope equipped with a focal plane array detector has enabled rapid acquisition of high magnification spectrochemical images, in transmission, with an effective geometric pixel size of ∼1 × 1 μm(2) at the sample plane. Examples, including standard imaging targets for scale and accuracy, as well as biomedical tissues and microorganisms, have been imaged with the new system and contrasted with data acquired at normal magnification and with a high magnification multi-beam synchrotron instrument. With this optics upgrade, one can now conduct rapid biodiagnostic ex vivo tissue imaging in-house, with images collected over larger areas, in less time (minutes) and with comparable quality and resolution to the best synchrotron source FTIR imaging capabilities.

Collagen is a major constituent in many life forms; in mammals, collagen appears as a component of skin, bone, tendon and cartilage, where it performs critical functions. Vibrational spectroscopy methods are excellent for studying the structure and function of collagen-containing tissues, as they provide molecular insight into composition and organization. The latter is particularly important for collagenous materials, given that a key feature is their hierarchical, oriented structure, organized from molecular to macroscopic length scales. Here, we present the first results of high-resolution FTIR polarization contrast imaging, at 1.1 μm and 20 nm scales, on control and mechanically damaged tendon. The spectroscopic data are supported with parallel SEM and correlated AFM imaging. Our goal is to explore the changes induced in tendon after the application of damaging mechanical stress, and the consequences for the healing processes. The results and possibilities for the application of these high-spatial-resolution FTIR techniques in spectral pathology, and eventually in clinical applications, are discussed.

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With lethal opportunistic fungal infections on the rise, it is imperative to explore new methods to examine virulence mechanisms.

We have used thermal source Fourier Transform Infrared (FTIR) microtomographic imaging to compare sea ice diatoms growing under different light conditions. A prototype tomography accessory was designed to have sufficient degrees of freedom to align any tilted cylindrical sample relative to the axis of rotation, minimizing the off-axis path traced during rotation. The lightweight device rests on the motorized stage to position the sample in the field-of-view and enable mosaic imaging. Reconstruction routines were tested with simulated and real phantoms, to assess limitations in the Radon back-projection method employed. The distribution and abundance of biochemicals is analysed for targets larger than a single FPA tile. Two and three dimensional (2D and 3D) FTIR spectrochemical images were obtained with a Focal Plane Array (FPA, nominal 1.1 μm pixel edges) for phantoms (polystyrene beads in polyvinyl alcohol matrix) and diatom cells harvested from land fast, first-year ice sites in Resolute Passage (74 43.628'N; 95 33.330'W) and Dease Strait (69° 1.11'N; 105° 21.29'W), Nunavut, Canada. The analysis of relative concentrations of organic matter within the encapsulating silica frustules of diatoms is important for a better understanding of both the physiological state and the individual cellular response to environmental pressures. Analysis of 3D FTIR images of Nitzschia frigida collected from beneath high (17-19 cm) and low (3-7 cm) snow depth revealed higher concentrations of lipids in diatoms collected under low snow cover, uniquely based on spectroscopically determined total 3D cell volume and biochemical content.

The metabolic actions of storage fungi and other microorganisms can cause spoilage and post-harvest losses in agricultural commodities, including flaxseed. These microbial contaminants are oxidized with hydroxyl radicals that are efficiently generated when ozone, hydrogen peroxide (H2O2), and ultraviolet (UV) light react in an advanced oxidative process (AOP). The present work explores what we believe is the first application of an AOP technology to reduce mould on whole brown and yellow flaxseed. The impact of AOP on storage and quality parameters was assessed by measuring the fatty acid value (FAV), germination rate, moisture content (MC), and visible mould growth after 12 weeks of storage. At 30°C and 75% relative humidity (RH), the yellow decontaminated flaxseed showed a 31% decrease in the number of seeds with visible mould without any adverse effect on germination rate, FAV and MC. In contrast, the same AOP treatment created an insignificant decrease in mould in stored brown flaxseed, at the cost of decreasing the germination rate and increasing FAV. Adverse effects of AOP on brown flaxseed were not readily apparent but became measurable after storage. Moreover, Fourier transform infrared (FTIR) spectroscopy was utilized to explore the rationale behind the different reactions of flaxseed varieties to AOP. The corresponding results indicated that the tolerance of yellow flaxseed to AOP might be related to its richness in olefins. The authors believe that technologies that harness advanced oxidative processes open new horizons in decontamination beyond ozone alone and towards increasing the shelf life of various agri-food products.

The consumption of plant-based proteins sourced from pulses is sustainable from the perspective of agriculture, environment, food security, and nutrition. Increased incorporation of high-quality pulse ingredients into foods such as pasta and baked goods is poised to produce refined food products to satisfy consumer demand. However, a better understanding of pulse milling processes is required to optimize the blending of pulse flours with wheat flour and other traditional ingredients. A thorough review of the state-of-the-art on pulse flour quality characterization reveals that research is required to elucidate the relationships between the micro-and nanoscale structures of these flours and their millingdependent properties, such as hydration, starch and protein quality, components separation, and particle size distribution. With advances in synchrotron-enabled material characterization techniques, there exist a few options that have the potential to fill knowledge gaps. To this end, we conducted a comprehensive review of four high-resolution nondestructive techniques (i.e., scanning electron microscopy, synchrotron X-ray microtomography, synchrotron small-angle X-ray scattering, and Fourier-transformed infrared spectromicroscopy) and a comparison of their suitability for characterizing pulse flours. Our detailed synthesis of the literature concludes that a multimodal approach to fully characterize pulse flours will be vital to predicting their end-use suitability. A holistic characterization will help optimize and standardize the milling methods, pretreatments, and post-processing of pulse flours. Millers/processors will benefit by having a range of well-understood pulse flour fractions to incorporate into food formulations.

The metabolic actions of storage fungi and other microorganisms can cause spoilage and post-harvest losses in agricultural commodities, including flaxseed. These microbial contaminants are oxidized with hydroxyl radicals that are efficiently generated when ozone, hydrogen peroxide (H 2 O 2 ) and ultraviolet (UV) light react in an advanced oxidative process (AOP). The present work explores what we believe is the first application of an AOP technology to reduce mould on whole brown and yellow flaxseed. The impact of AOP on storage and quality parameters was assessed by measuring the fatty acid value (FAV), germination rate, moisture content (MC) and visible mould growth after 12 weeks of storage at 30°C and 75% relative humidity (RH). Under these conditions, the yellow decontaminated flaxseed showed a 31% decrease in the number of seeds with visible mould without any adverse effect on germination rate, FAV and MC. In contrast, the same AOP treatment created an insignificant decrease in mould in stored brown flaxseed, at the cost of decreasing the germination rate and increasing FAV. The adverse effects of AOP on brown flaxseed were not readily apparent but became measurable after storage. Moreover, Fourier transform infrared (FTIR) spectroscopy was utilized to explore the rationale behind the different reactions of flaxseed varieties to AOP. The corresponding results indicated that the tolerance of yellow flaxseed to AOP might be related to its richness in olefins. The authors believe that technologies that harness advanced oxidative processes open new horizons in decontamination beyond ozone alone and towards increasing the shelf life of various agri-food products.