Search Results (41)

The global challenge of food insecurity requires innovative approaches for sustainable food production and waste valorization. This study investigates the valorization of oat hulls, an abundant lignocellulosic by-product from oat manufacturing, by solid-state fermentation using edible filamentous fungi. Oat hulls sourced from oatmeal industrial side-streams were used as the sole substrate in co-cultures of Neurospora intermedia and Rhizopus oryzae. The fermentation process was optimized and upscaled, with fungal growth monitored via CO₂ efflux and modeled to assess substrate utilization. Comprehensive analyses revealed a significant increase in protein concentration (p < 0.05) in the fermented oat hulls compared to the non-fermented controls. The resulting product was successfully incorporated into granola bars, which underwent sensory evaluation and received positive feedback, demonstrating its potential as a value-added food ingredient. These findings highlight the feasibility of using edible fungi to upcycle cereal processing by-products into nutritionally enhanced alternative protein sources, supporting both food system sustainability and circular bioeconomy objectives. Full article

Beetroot-based additives are interesting for enriching bread in terms of bioactive compounds. The objective of this study was to determine the effect of the following beetroot-based additives: a beetroot lyophilizate powder (wheat–oat baking mix flour was replaced in proportions of 2.5, 5.0, 7.5, 10%), a beetroot juice (water was replaced with juice in proportions of 25, 50, 75, 100%) and a by-product of beetroot juice production, i.e., pomace (wheat–oat baking mix flour was replaced in proportions of 2.5, 5.0, 7.5, 10%) on the quality of wheat–oat bread and the content of bioactive components in this type of bread. The properties of the dough were also assessed. The type and percentage level of partially replacing wheat–oat baking mix flour or water with beetroot-based additives had a significant impact on water absorption, dough development, and stability time of the tested dough. The beetroot juice (BJ) and powder (BLP) had the most significant impact on the rheological properties of the dough, whereas the pomace (BP) had the smallest effect. Beetroot-based additives, especially powder and juice, reduced the volume of bread (from 199 to 148 cm³/100 g of bread) but did not change oven loss [%] and bread crumb porosity index. Breads with these additives showed higher increased values for dough yield [%] and bread yield [%] (for beetroot powder—by 10% compared to the control sample (133.37% and 113.83%)). Tested additives had an impact on the crust and crumb color of the tested wheat–oat breads. The proposed additives significantly increased the antioxidant activity, total phenolic content, and betalain content in the bread samples. The above results showed that, from a technological point of view, replacing water or flour in the wheat–oat bread recipe with beetroot-based additives with a maximum concentration of 5% for BP or BLP and 50% for BJ allows for obtaining a product of good quality. Full article

Citrus by-products are increasingly recognized as a valuable source of bioactive compounds (BCs), particularly flavonoids. Their incorporation into food matrices as functional ingredients aligns with sustainability goals and consumer demand for health-promoting products. However, challenges such as poor stability and undesirable sensory properties limit their direct use in food systems. This study aimed to develop and evaluate functional cookies enriched with microencapsulated flavonoid-rich extracts derived from lemon and orange peels. Flavonoids were extracted with hydroethanolic solvent and characterized by HPLC-DAD. The extracts exhibited high total flavonoid contents: 1960.1 mg/L for orange and 845.7 mg/L for lemon. The extracts were encapsulated using a 1% sodium alginate and 1.36% corn starch blend, producing thermally stable microbeads with flavonoid retention higher than 85% after heating at 230 °C for 30 min. These microbeads were incorporated into gluten-free oat and buckwheat cookies, delivering 166.11 mg/100 g (orange) and 177.13 mg/100 g (lemon) of flavonoids in the product, which covers approximately one-third of the recommended daily intake. Sensory analysis using triangle tests (ISO 4120) (n = 23) showed no significant difference (p > 0.05) between control and enriched cookies, indicating successful masking of potential bitterness or astringency associated with flavonoids. These results demonstrate the effectiveness of microencapsulation in protecting citrus flavonoid-rich extracts and support the development of sustainable, health-oriented bakery products. Moreover, this approach promotes the valorization of agro-industrial by-products, contributing to a more circular food supply chain. Full article

This study aimed to assess the use of selected raw materials, such as whole-grain oat flakes, pumpkin seeds, sunflower seeds, and flaxseeds, to obtain bars using baking and drying methods. Modifying the bars’ composition involved selecting the fibre preparation, replacing water with NFC juice, and using fresh apple juice and apple pomace. The Psyllium fibre preparation, also in the form of a mixture with apple fibre, was the most useful in dough cohesion and the quality of the bars. Baked bars were characterised by higher sensory quality than those obtained by drying. Microwave–convection drying was a good alternative to baking, primarily due to the lower temperature resulting in a lower acrylamide content and comparable product quality. The basic grain ingredients and fibre preparations mainly shaped the nutritional and energy value and the sensory and microbiological quality. Modifying the recipe using NFC or fresh juice and apple pomace allowed the bars to develop new properties and quality characteristics. The use of NFC juices resulted in a reduction in the pH of the bars, which is associated with a higher microbiological quality of the bars. All bars had low acrylamide content, significantly lower than the permissible level. Using fresh pomace or fibre preparations made from by-products is a possibility to increase the fibre content in the bars and a method of managing by-products. Full article

Background: Consumer demand for plant-based milk alternatives, particularly oat-based milk, has increased due to perceived health benefits and environmental sustainability. However, challenges remain in improving their nutritional profile and physical stability while promoting the use of local agricultural resources and reducing food waste. Methods: This study developed and evaluated fortified oat-based milk formulations using locally sourced oats cultivated in central Italy. Two valorization strategies were tested: (i) the addition of raspberry powder derived from juice processing byproducts and (ii) the substitution of water with infusions of raspberry and olive leaves. The nutritional composition, antioxidant activity, physical stability, and sensory properties were assessed. Results: Replacing water with leaf infusions significantly increased total polyphenol content (up to 688 mg GAE/100 g DW) and antioxidant activity but compromised physical stability, resulting in higher separation indexes during refrigerated storage. Conversely, adding raspberry powder moderately enhanced antioxidant properties while maintaining emulsion stability. Sensory evaluation showed that enriched formulations reduced undesirable attributes (e.g., floury and cereal notes), although higher concentrations of leaf infusions increased astringency and bitterness. Conclusions: The fortification of oat-based milk with locally sourced raspberry powders and leaf infusions effectively enhances its nutritional and antioxidant properties while influencing its physical and sensory characteristics. This strategy supports the valorization of local agricultural byproducts and promotes the development of sustainable, functional plant-based beverages. Full article

The main objective of this experiment was to investigate the technological potential of upcycling unsparged non-conventional brewers’ spent grains (BSGs) in bread-making and assess the comparative quality of bread enriched with non-fermented and lactic acid-fermented BSGs obtained from mashes brewed with starch adjuncts of buckwheat and oats. After the runoff of the first wort, unsparged non-conventional BSGs with approximately 75% moisture, acidic pH, and yield in the soluble extract above 56.6% (w/w d.m.) were used in substituting wheat flour with 5 and 15% (w/w d.m.) in bread-making recipes. The highest loaf volume value (318.68 cm³/100 g) was observed for 5% fermented buckwheat-BSG addition. Except for the samples with 5% fermented BSGs, specific volumes decreased. Crumb moisture was reduced by up to 22% for all samples, with this parameter related to bread weight. Bread porosity, elasticity, acidity, and overall sensory acceptability were better for fermented than non-fermented BSGs. The results proved that non-conventional BSGs with buckwheat and oats addition have the potential to be valorized in new bread assortments, and lactic acid fermentation applied to the BSGs is beneficial, even for overall sensory acceptability and quality of baked end-products. Technological, buckwheat-BSG was more convenient than oats-BSG. Further research continues to optimize and upscale Technology Readiness Levels. Full article

The importance of the valorization of industrial by-products has led to increasing research into their reuse. In this research, the innovative by-product okara oat flour, derived from the vegetable beverage industry, was studied. Oat okara sourdough was also produced and evaluated. The microbiological identification and typing involved bacterial and yeast isolates from both flour and sourdough. Untargeted metabolomics allowed the identification of biomarkers of fermented flour, such as phenolic classes, post-fermentation metabolites, fatty acids, and amino acids. The microorganisms most found were Weissella confusa, Enterococcus faecium, Pediococcus pentosaceus, and Pichia kudriavzevii, while Saccharomyces cerevisiae appeared only at the end of the sourdough’s back-slopping. Untargeted metabolomics identified a total of 539 metabolites, including phenolic compounds, lipids, amino acids, and organic acids. An increase in polyphenols released from the food matrix was detected, likely because of the higher bio-accessibility of phenolic metabolites promoted by microbial fermentation. Fermentation led to an increase in isoferulic acid, p-coumaric acid, sinapic acid, and a decrease in amino acids, which can be attributed to the metabolism of lactic acid bacteria. Some key markers of the fermentation process of both lactic acid bacteria and yeast were also measured, including organic acids (lactate, succinate, and propionate derivatives) and flavor compounds (e.g., diacetyl). Two bioactive compounds, such as gamma-aminobutyric acid and 3-phenyl-lactic acid had accumulated at the end of fermentation. Taken together, our findings showed that oat okara flour can be considered an excellent raw material for formulating more sustainable and functional foods due to fermentation promoted by autochthonous microbiota. Full article

The aim of the present study was to determine the characteristics of oat cookies with the addition of apple (“A”: 5, 10%) and carrot pomace (“C”: 5, 10%). Modifying the recipe and fortifying the oat cookies with such byproducts decreased the hardness and increased the elasticity and chewiness. A colour change in the products containing fruit pomace was also observed. The use of carrot and apple residues resulted in a decrease in the value of the L* parameter, i.e., colour brightness. Moreover, for cookies containing carrot pomace, a significant increase in colour chromaticity towards red and yellow was observed. Fortified oatmeal cookies contained more polyphenols (0.67 mg/g–“CP”, control probe; 0.92 mg/g–“C10”) and fat (21.85%–“CP”; 22.55%–“A10”) but less protein (10.78%–“CP”; 10.25%–“C10”). A higher content of some minerals, i.e., P (0.334%–“CP”; 0.468%–“A10”), K (0.325%–“CP”; 0.387%–“C10”), and Ca (0.057%–“CP”; 0.073%–“C10”), was recorded in the cookies fortified with pomace. The obtained results indicate the significant impact of the addition of apple and carrot residues on the textural properties, colour parameters, and chemical composition of oat cookies. Pomace can be used to increase the content of antioxidants and microelements in this type of product. Full article

Nutraceuticals obtained from sprouted wheat and oat grains and processing by-products (bran and hull, respectively) naturally containing antioxidant and anti-inflammatory compounds were evaluated. The objective of this study was the development of a cereal-based nutraceutical formula combining extracts from sprouts and by-products and the exploration for potential synergetic effects in their bioactive properties. The antioxidant and anti-inflammatory capacities, glycemic index, phytic acid, and β-glucan of individual wheat bran hydrolysate (EH-WB), sprouted wheat (SW), oat hull hydrolysate (EH-OH), sprouted oat (SO), and combined ingredients (CI 1, CI 2, and CI3) were used to tailor an optimal nutraceutical formula. The three blend ingredients (CI 1, CI2, and CI3) were formulated at different ratios (EH-WB:SW:EH-OH:SO; 1:1:1:1, 2:1:2:1, and 1:2:1:2, w:w:w:w, respectively). The resulting mixtures showed total phenol (TPs) content ranging from 412.93 to 2556.66 µmol GAE 100 g⁻¹ and antioxidant capacity values from 808.14 to 22,152.54 µmol TE 100 g⁻¹ (ORAC) and 1914.05 to 7261.32 µmol TE 100 g⁻¹ (ABTS^•+), with Fe³⁺ reducing ability from 734. 02 to 8674.51 mmol reduced Fe 100 g⁻¹ (FRAP) for the individual ingredients produced from EH-WB and EH-OH, where high antioxidant activity was observed. However, the anti-inflammatory results exhibited an interesting behavior, with a potentially synergistic effect of the individual ingredients. This effect was observed in CI2 and CI3, resulting in a higher ability to inhibit IL-6 and TNF-α than expected based on the anti-inflammatory values of their individual ingredients. Similar to the antioxidant properties, oat-based ingredients significantly contributed more to the anti-inflammatory properties of the overall mixture. This contribution is likely associated with the β-glucans and avenanthramides present in oats. To ensure the bioaccessibility of these ingredients, further studies including simulated digestion protocols would be necessary. The ingredient formulated with a 2:1 hydrolysate-to-sprout ratio was the most effective combination, reaching higher biological characteristics. Full article

The viability of incorporating agricultural by-products, such as oat husks, not yet explored in limestone-based composites, as more sustainable alternatives for use as novel aggregates may be improved through the adoption of well-known valorisation strategies applied to other plant-based resources. In this context, this work innovates by assessing how treatments on oat husk surfaces and the choice of limestone-based binders impact the mechanical performance of composites. The strategy adopted to achieve these objectives, in addition to carrying out the physical and geometric characterisation of the husks, consists of treating the husks’ surface using washing cycles in water, cement/pozzolan binder, and linseed oil. Furthermore, matrices combining cement, calcium hydroxide Ca(OH)₂, and microsilica (SiO₂) were used. In conclusion, even though the effects of different binder combinations are inconsistent, coating oat husks—especially with linseed oil—works well in delaying particle degradation and improving mechanical strength compared to untreated particles. Furthermore, when aggregates are substituted with the longer and lamellar particles of oat husk, the impact of the water/cement ratio on mechanical performance and composite workability significantly decreases. Full article

The objective of this study was to modify a protein-rich by-product, generated during β-glucan production, to render it appropriate for incorporation into meat products. Additionally, the study sought to assess the quality of a prototype meat product containing oat additives, depending on its concentration. Through hydrolyzation, its solubility was enhanced, making it suitable for broader applications in food products. With an average protein content of 52% and fat content of 6%, the pure hydrolysate exhibited a notable ferric ion reduction, as well as metal chelating properties. In meat formulations, the hydrolysate was integrated at concentrations of 1%, 2%, and 3%, relative to the meat mass. Following cooking and subsequent storage for 21 days, assessments were conducted every 7 days to evaluate colour retention, texture, and oxidation status. At concentrations of 2% to 3% (equivalent to 2–3 g/100 g), the hydrolysate significantly enhanced colour stability, while concurrently fostering oxidation. Notably, cohesiveness and resilience were augmented, with no discernible impact on hardness. The application of oat protein hydrolysate, particularly at 2–3 g/100 g, serves as a viable strategy for enhancing colour stability in meat formulations. However, its pro-oxidative effects necessitate supplementation with antioxidants to mitigate potential deterioration in the final product. Full article

Amidst the escalating global demand for protein-rich livestock feed, there’s an urgent call to explore innovative alternatives. Insects, renowned for their rich protein, lipid, and nutrient profiles, offer a sustainable solution. Integrating agricultural waste into insect diets emerges as a promising strategy to alleviate rearing costs. However, large-scale investigations into by-product valorization remain limited. Thus, our study aims to evaluate Greek agricultural by-products—brewer’s spent grains, rice bran, oat and maize by-products, and animal feed mill leftovers—as potential feedstock for Tenebrio molitor larvae, an insect species that is authorized by the European Union for both livestock feed and human consumption. In this study, the larval growth and body composition were assessed in commercial trays, unveiling optimal performance with rice bran and brewer’s spent grains. Conversely, larvae fed with animal feed mill leftovers and maize by-products displayed suboptimal outcomes. These findings underscore the potential efficacy of integrating locally produced agricultural by-products into T. molitor commercial production. Such an approach not only addresses the growing demand for protein-rich livestock feed but also offers a sustainable solution to agricultural waste management. In conclusion, our research contributes valuable insights towards developing economically viable insect farming. Full article

Brewers’ spent grains (BSG) are the major byproduct of the brewing industry. Recently, it has been found that β-glucan, which can be used as a food supplement, can be extracted from BSG and offers the greatest added value. This study aimed to investigate the effects of temperature (45–90 °C) and time (30–120 min) on β-glucan extraction efficiency when using hot water extraction. β-glucan was precipitated upon 80% ethanol addition. The chemical compositions were examined. The highest β-glucan concentration and yield were obtained at a temperature and time of 60 °C and 90 min, respectively. The functional properties of the extracted β-glucan were analyzed and compared with other commercial stabilizers such as sodium carboxymethyl cellulose (CMC), xanthan gum, gum arabic, and oat β-glucan. All stabilizers exhibited non-Newtonian flow behavior, except for gum arabic, which exhibited Newtonian flow behavior. The water holding capacity of BSG β-glucan was 6.82 g/g and the creaming index of the emulsions stabilized with BSG β-glucan was 89.05%. BSG β-glucan improved the color and stability of orange juice by reducing the precipitation of orange pulp. This study illustrated that BSG β-glucan can be used as a stabilizer and viscosity enhancer in foods, depending on the concentration, which can be applied to a variety of foods. Full article

Wheat bran (WB) and oat hull (OH) are two interesting undervalued cereal processing sources rich in total dietary fibre (TDF) and other associated bioactive compounds, such as β-glucans and polyphenols. The aim of this study was to optimise a combination chemical (enzymes) and physical (high hydrostatic pressure-temperature) strategies to increase the bioaccessibility of bioactive compounds naturally bound to the bran and hull outer layers. WB and OH were hydrolysed using food-grade enzymes (UltraFloXL and Viscoferm, for WB and OH, respectively) in combination with HPP at different temperatures (40, 50, 60 and 70 °C) and hydrolysis either before or after HPP. Proximal composition, phytic acid, β-glucans, total phenolics (TPs) and total antioxidant activity (TAC) were evaluated to select the processing conditions for optimal nutritional and bioactive properties of the final ingredients. The application of the hydrolysis step after the HPP treatment resulted in lower phytic acid levels in both matrices (WB and OH). On the other hand, the release of β-glucan was more effective at the highest temperature (70 °C) used during pressurisation. After the treatment, the TP content ranged from 756.47 to 1395.27 µmol GAE 100 g⁻¹ in WB, and OH showed values from 566.91 to 930.45 µmol GAE 100 g⁻¹. An interaction effect between the temperature and hydrolysis timing (applied before or after HPP) was observed in the case of OH. Hydrolysis applied before HPP was more efficient in releasing OH TPs at lower HPP temperatures (40–50 °C); meanwhile, at higher HPP temperatures (60–70 °C), hydrolysis yielded higher TP values when applied after HPP. This effect was not observed in WB, where the hydrolysis was more effective before HPP. The TP results were significantly correlated with the TAC values. The results showed that the application of optimal process conditions (hydrolysis before HPP at 60 or 70 °C for WB; hydrolysis after HPP at 70 °C for OH) can increase the biological value of the final ingredients obtained. Full article

Hazel leaf, a by-product of hazelnuts, is commonly used in traditional folk medicine in Portugal, Sweden, Iran and other regions for properties such as vascular protection, anti-bleeding, anti-edema, anti-infection, and pain relief. Based on our previous studies, the polyphenol extract from hazel leaf was identified and quantified via HPLC fingerprint. The contents of nine compounds including kaempferol, chlorogenic acid, myricetin, caffeic acid, p-coumaric acid, resveratrol, luteolin, gallic acid and ellagic acid in hazel leaf polyphenol extract (ZP) were preliminary calculated, among which kaempferol was the highest with 221.99 mg/g, followed by chlorogenic acid with 8.23 mg/g. The inhibition of ZP on α-glucosidase and xanthine oxidase activities was determined via the chemical method, and the inhibition on xanthine oxidase was better. Then, the effect of ZP on hyperuricemia zebrafish was investigated. It was found that ZP obviously reduced the levels of uric acid, xanthine oxidase, urea nitrogen and creatinine, and up-regulated the expression ofOAT1 and HPRT genes in hyperuricemia zebrafish. Finally, the targeted network pharmacological analysis and molecular docking of nine polyphenol compounds were performed to search for relevant mechanisms for alleviating hyperuricemia. These results will provide a valuable basis for the development and application of hazel leaf polyphenols as functional ingredients. Full article