X-ray microcomputed tomography (μCT) enables non-destructive visualization of the internal microstructures of grains. In this study, underutilized grains with growing demand, including sorghum, millet, buckwheat, and quinoa, were investigated as valuable alternatives to traditional cereals. A comprehensive 3D characterization of their internal architecture was performed to provide quantitative insights relevant to food processing and functional applications. By determining the spatial organization and relative volumes of major grain components, structural factors influencing mechanical behavior, hydration kinetics, nutrient distribution, and overall functional performance can be better understood. Image reconstruction and segmentation software were applied to CT datasets to generate 3D images from 2D cross-sectional images, enabling volumetric structural analysis. This approach facilitates the identification and quantification of internal microstructural features that are often inaccessible through conventional imaging techniques. The total grain volume, as well as the volume of major anatomical components, were quantified. Phenotypic characterization included grain shape, internal component morphology, and spatial organization. The embryo, endosperm, and outer layers were clearly distinguishable in all grains, while in quinoa, additional structures such as the perisperm, funicle, and cotyledons were also resolved. The CT-derived volumetric and spatial datasets generated in this study contribute to the limited body of quantitative 3D grain anatomy literature, which has predominantly focused on single crops or relied on schematic rather than true volumetric representations. These findings provide a valuable resource for advancing structural understanding and application of underutilized grains in the food sector.

Raw milk obtained from cows infected with H5N1 requires to be treated to inactivate the virus prior to disposal. In this context, a hurdle approach was evaluated to inactivate Phi6 bacteriophage (potential H5N1 surrogate) in raw milk as a risk management option for dairy farms. The treatment involved adding hydrogen peroxide (0.1, 1, or 10 mM) and sodium thiocyanate (0.2, 2.4, or 24 µM) to raw milk, which served as substrates for the lactoperoxidase system to produce hypothiocyanite. The substrates were also a source of free radicals via UV-C mediated photo-degradation in an Advanced Oxidation Process (AOP). The raw milk was inoculated with Phi6 bacteriophage (7-8 log PFU/mL) in the presence of thiocyanate and/or hydrogen peroxide, held for 10 min at 23 °C, before passing through a spiral UV-C reactor. The infective Phi6 phages were determined on a cell lawn of the Pseudomonas host cell. It was found that the lactoperoxidase system, in the absence of UV-C, supported a 3.01 ± 0.07 log PFU/mL reduction of phage when 10 mM hydrogen peroxide and 24 µM sodium thiocyanate were applied to raw milk. Hydrogen peroxide or thiocyanate alone supported <1.2 log reduction of Phi6. When UV-C (137 mJ/cm2) was applied in the presence of added hydrogen peroxide (10 mM) and thiocyanate (24 µM), the log reduction of phages increased to 4.49 ± 0.50 log PFU. The flow pattern of milk also influenced the efficacy of treatment, suggesting that homogenous mixing during passage through the reactor was an important factor. The Phi6 inactivation was partly supported by the direct action of UV photons, the generation of free radicals (hydroxyl-radical and thiocyanate), and lactoperoxidase. When the lactoperoxidase was thermally inactivated, the log reduction was increased to 5.63 ± 0.10 log PFU, suggesting competition for hydrogen peroxide and thiocyanate between the enzyme and AOP. The study demonstrated proof of principle for a nonthermal process for inactivating viruses in raw milk.

There has been a growing interest in incorporating sprouted wheat wholemeal (SWW) into whole grain baking, driven by its heightened nutritional content and improved nutrient bioavailability. This study aimed to assess how substituting soft wheat flour (SWF) with various levels of wheat wholemeal (unsprouted and sprouted) impacts the quality and sensory characteristics of hard pretzel sticks, which are globally enjoyed as popular snacks. The dough samples containing wholemeal did not demonstrate the same extensibility as the SWF dough sample. Additionally, substituting SWF with wholemeal increased the resistance to extension. Analysis of the Raman spectra of SWF and two other selected dough samples containing 75 % unsprouted wheat wholemeal (UWW) or SWW indicated α-helix as the dominant protein secondary structure. As the ratio of wholemeal to SWF increased in both unsprouted and sprouted wheat pretzel samples, protein and fiber content increased and starch content decreased, resulting in a decreased peak viscosity in an RVA (Rapid Visco Analyzer) test. The findings also showed no significant difference in hardness between the SWF pretzel sample and all other samples (p > 0.05), except when SWF was replaced with the highest level (75 %) of SWW, resulting in a significantly softer texture. Color analysis revealed that the introduction of wholemeal led to a decrease in the L* value, indicating a darker surface appearance in the samples, likely due to the presence of bran. Finally, sensory evaluation determined that replacing SWF with 25 % SWW resulted in the creation of a sample most similar to SWF in terms of sensory attributes. This research paves the way for future studies and advancements in the formulation and analysis of pretzel dough, creating opportunities to improve both the quality of the product and consumer satisfaction.

Sprouting can enhance the bioavailability and stimulate the production of health-promoting compounds. This research explored the potential health benefits of wheat sprouting, focusing on underexplored areas in existing literature such as alterations in phenylalanine ammonia-lyase (PAL) activity and glutathione levels during wheat sprouting. Furthermore, special attention was directed toward asparagine (Asn), the main precursor of acrylamide formation, as regulatory agencies are actively seeking to impose limitations on the presence of acrylamide in baked products. The results demonstrate elevated levels of PAL (4.5-fold at 48 h of sprouting), antioxidants, and total phenolics (1.32 mg gallic acid equivalent/g dry matter at 72 h of sprouting), coupled with a reduction in Asn ( i.e. 11-fold at 48 h of sprouting) and glutathione concentrations, after wheat sprouting. These findings suggest that sprouting can unlock health-promoting properties in wheat. Optimizing the sprouting process to harness these benefits, however, may have implications for the techno-functionality of wheat flour in food processing.

Sprouted wheat wholemeal was reported to enhance the nutritional and sensory properties of cereal products, but few human studies exist. The effect of blending 50 % sprouted wheat wholemeal in a bread recipe on the postprandial glycemic and satiety responses, and sensory-related sensations was investigated in this randomized crossover human study with 12 healthy participants. Capillary blood samples were collected and glycemic response was determined at 0, 15, 30, 45, 60, 90, 120 min. Satiety visual analogue scales were given every 30 min. While substituting bread wheat flour with sprouted wheat wholemeal significantly increased the α-amylase activity in the dough (p < 0.05), it did not alter in vitro digestibility or postprandial glycemic and satiety responses (p > 0.05). Likewise, participant overall acceptability was not adversely affected. Sprouted wheat wholemeal can be used as a functional ingredient in breadmaking, although it did not, in this study, significantly affect digestibility parameters.

To unravel the effect of sprouted wheat wholemeal (SWW) on bread characteristics, baking performance of SWW and commercial white bread wheat flour (BWF) blends was investigated. The inclusion of soft or hard SWW increased the total monosaccharide and reducing sugar concentrations, α-amylase and proteolytic activity in dough liquor (DL) relative to what was found in DL obtained from dough prepared with only BWF or unsprouted wheat wholemeal (UWW). The apparent bulk viscosity and air-water interfacial rheological properties of DL were changed upon inclusion of UWW and SWW in the recipes, likely reflecting changes in the DL arabinoxylan and protein content, while the surface tension of dough liquor was not altered by inclusion of UWW or SWW. The interfacial elastic modulus correlated positively with the protein concentration of DL, while bread loaf volume was negatively correlated with DL protein concentration and air-water interfacial elastic and viscous moduli. DL bulk viscosity, conversely, had a more complex relation to bread loaf volume. Besides affecting the DL properties, sprouting also altered the gluten aggregation properties. More research is needed to identify the fine interplay between all these factors determining breadmaking performance.

Wheat kernels harbor a diverse microflora that can negatively affect the suitability of the grains for further processing. To reduce surface microflora, a kernel disinfection method is required that does not affect grain functionality. Three different versions of gas phase hydroxyl-radical processes were compared with the common method for grain disinfection, that is, a bleach treatment. The gas phase hydroxyl-radicals are generated by the UV-C mediated degradation of hydrogen peroxide and/or ozone in a near water-free process. It was found that treating kernels with a bleach solution could reduce total aerobic count (TAC) and fungal count to below the level of enumeration. In comparison, the gas phase hydroxyl-radical treatment, that is, H2 O2 -UV-ozone treatment, could support a 1.3 log count reduction (LCR) in TAC and a 1.1 LCR in fungal count. The microbial load reduction for the wholemeal samples was less pronounced as endophytic microorganisms were less affected by all treatments, hinting at a limited penetration depth of the treatments. Despite reducing the microbial load on the kernel surface through the bleach and H2 O2 -UV-ozone treatments, none of these treatments resulted in a reduced microbial count on grains that underwent sprouting after the treatments. No negative effect on germination power or development of the seedling was observed for any of the treatments. The gluten aggregation behavior and xylanase activity of the wholemeal also remained unchanged after the gas phase hydroxyl-radical treatments. Our findings suggest that UV-H2 O2 -ozone treatment shows promise for dry-kernel disinfection, but further optimization of the processing parameters is required.

The COVID-19 pandemic has generated increased interest in potential transmission routes. In food retail settings, transmission from infected customers and workers and customers through surfaces has been deemed plausible. However, limited information exists on the presence and survival of SARS-CoV-2 on surfaces, particularly outside laboratory settings. Therefore, the purpose of this project was to assess the presence of the virus at commonly found surfaces at food retail stores and the potential role that these spaces play in virus transmission. Samples (n=957) were collected twice a week for a month in food-retail stores within Ontario, Canada. High-touch surfaces were identified and surveyed in 4 zones within the store (payment stations, deli counters, refrigerated food section and carts and baskets). The samples were analyzed using a molecular method, i.e., reverse transcriptase quantitative Polymerase Chain Reaction (RT-qPCR). Regardless of the store's location, the sampling day or time, the location of the surface within the store or the surface material, all samples tested negative for SARS-CoV-2. These results suggest that the risk of exposure from contaminated high-touch surfaces within a food retailer store is low if preventive measures and recommended sanitizing routines are maintained.

One type of functional food that has been receiving much attention is food rich in prebiotics. The old but still valid definition of prebiotics defines them as non-digestible food components that selectively stimulate the growth and/or activity of the beneficial bacteria in the colon and, as a result, improve the host health. Cereals, as one of the main components in the human diet, contain substantial levels of dietary fiber with probable prebiotic potential. In addition, dietary fiber, particularly soluble dietary fiber, has recently emerged as a promising natural highly functional food ingredient in food production. This review focuses on the prebiotic potential of cereal dietary fiber types and covers the achievements and developments regarding its isolation. First, the probiotic and prebiotic concepts will be discussed. Next, different components of dietary fiber and their effect on the host bacteria through in vitro and/or in vivo studies will be reviewed. In a last part, this paper also discusses means of boosting the prebiotic properties of cereal components and innovative strategies for the extraction of cereal dietary fiber. The review focuses on wheat as a leading cereal crop that is widely and intensely used throughout the world in food production.

To optimize the exopolysaccharide (EPS) production by Lactobacillus rhamnosus 519, fermentation experiments using response surface methodology (RSM) were carried out. Studying the effect of different carbon and nitrogen sources on EPS production in skimmed milk (SM) resulted in selecting of sucrose and yeast nitrogen base (YNB) for the optimization experiments. The effect of pH, incubation time, YNB concentration and sucrose concentration on EPS production in SM was studied. The results showed that pH, incubation time and sucrose concentration have significant effect on EPS production (P≤0.05). Maximum EPS production was 256mg/L and the optimum pH, incubation time, YNB concentration and sucrose concentration for EPS production were found to be 5.7, 49h, 9.8g/L and 25.8g/L, respectively.

Lactobacillus reuteri harbours alternative enzymes for sucrose metabolism, sucrose phosphorylase, fructansucrases, and glucansucrases. Sucrose phosphorylase and fructansucrases additionally contribute to raffinose metabolism. Glucansucrases and fructansucrases produce exopolysaccharides as alternative to sucrose hydrolysis. L. reuteri LTH5448 expresses a levansucrase (ftfA) and sucrose phosphorylase (scrP), both are inducible by sucrose. This study determined the contribution of scrP to sucrose and raffinose metabolism in L. reuteri LTH5448, and elucidated the role of scrR in regulation sucrose metabolism. Disruption of scrP and scrR was achieved by double crossover mutagenesis. L. reuteri LTH5448, LTH5448ΔscrP and LTH5448ΔscrR were characterized with respect to growth and metabolite formation with glucose, sucrose, or raffinose as sole carbon source. Inactivation of scrR led to constitutive transcription of scrP and ftfA, demonstrating that scrR is negative regulator. L. reuteri LTH5448 and the LTH5448ΔscrP or LTH5448ΔscrR mutant strains did not differ with respect to glucose, sucrose or raffinose utilization. However, L. reuteri LTH5448ΔscrP produced more levan, indicating that the lack of sucrose phosphorylase is compensated by an increased metabolic flux through levansucrase. In conclusion, the presence of alternate pathways for sucrose and raffinose metabolism and their regulation indicate that these substrates, which are abundant in plants, are preferred carbohydrate sources for L. reuteri.

Summary Exopolysaccharide (EPS) production by Lactobacillus delbrueckii subsp. bulgaricus SZ2 was optimised in modified MRS (M‐MRS) using the response surface methodology (RSM). Maximum EPS production was 74.3 ± 2 mg/L, and the optimised values of the three variables predicted for maximum EPS production included a temperature of 38.7 °C, Bacto‐casitone and glucose concentrations of 24.5 and 29.6 g/L, respectively. To compare EPS production in MRS and skimmed milk (SM), the kinetics of EPS formation and growth were monitored in M‐MRS, SM, skimmed milk plus 2% additional sucrose (Suc‐SM) and skimmed milk containing Bacto‐casitone (20 g/L) and yeast nitrogen base (5 g/L) (BY‐SM). EPS production in all the media tested seemed to be growth‐related. The EPS/cell ratios were determined to be 3.12 × 10 −10 , 1.43 × 10 −10 , 4.42 × 10 −11 and 3.16 × 10 −11 mg/cell, in Suc‐SM, SM, M‐MRS and BY‐SM, respectively, clearly indicating the greater effect of C/N ratio when cell behaviour in EPS production is considered.

SummaryThe Brea gum (BG) is a hydrocolloid obtained as phloematic exudate from Cercidium praecox. The exudate was purified by solution and subsequent drying. BG showed high solubility in water 28.3% at 25 °C that increased as temperature was raised. Viscosity of BG solutions increased with BG concentration increase and temperature decrease. Addition of acid or alkali produced changes in solution viscosity as the electrostatic charges on the macromolecule were altered. Solution density at 25 °C increased linearly with hydrocolloid concentration up to saturation. BG lowered the surface tension of water to 51.3 mN m−1 when BG concentration was 5%, remaining constant for higher concentrations. The diameter of oil droplets emulsified decreased and foamability increased with BG concentration increase up to 5% of BG. BG presents adequate functional characteristics for use as stabiliser in preparations with high content of insoluble solids and as stabiliser and emulsifier in emulsions and foams.