Oat Processing Research Articles

Enhancing phenolic and lipid compound production in oat bran via acid pretreatment and solid-state fermentation with Aspergillus niger

Oat (Avena sativa) processing generates a large amount of by-products, especially oat bran. These by-products are excellent sources of bioactive compounds such as polyphenols and essential fatty acids. Therefore, enhancing the extraction of these bioactive substances and incorporating them into the human diet is critical. This study investigates the effect of acid pretreatment on the solid-state fermentation of oat bran with Aspergillus niger, with an emphasis on the bioaccessibility of phenolic acids and lipid profile. The results showed a considerable increase in reducing sugars following acid pretreatment. On the sixth day, there was a notable increase in the total phenolic content, reaching 58.114 ± 0.09 mg GAE/g DW, and the vanillic acid level significantly rose to 77.419 ± 0.27 μg/g DW. The lipid profile study revealed changes ranging from 4.66 % in the control to 7.33 % on the sixth day of SSF. Aside from biochemical alterations, antioxidant activity measurement using the DPPH technique demonstrated the maximum scavenging activity on day 4 (83.33 %). This study highlights acid pretreatment's role in enhancing bioactive compound accessibility in solid-state fermentation and its importance for functional food development.

Effect of kilning on the macronutrient composition profile of three Swedish oat varieties

AbstractBackground and ObjectivesKilning is crucial in oat processing, to prevent rancidity and extend shelf‐life. This study examines kilning effects on the macronutrient composition in Swedish oat varieties Galant, Fatima, and Belinda. We compared two kilning methods: one mimicking industrial practice and a simplified version. We analyzed dietary fibers (arabinoxylan, β‐glucan), protein and amino acids, lipid profile, lipase activity, and antioxidant capacity in these oat samples.FindingsDistinct compositional differences were found: Galant had low lipid content, Fatima had elevated lipid and protein levels with fewer carbohydrates, and Belinda was rich in β‐glucan and dietary fibers. Both kilning procedures had similar impacts on all varieties, causing no major changes in dietary fiber or total protein content, but resulting in a 20% decrease in soluble proteins. Kilning decreased levels of several amino acids in Belinda, while the l‐glutamate/glutamine ratio increased across all varieties. Lipid analysis showed minimal kilning‐induced changes; yet, antioxidative capacity diminished. Both kilning methods effectively inactivated lipases.ConclusionsThese findings emphasize macronutrient variations among oat varieties and the effect of kilning on soluble proteins, amino acids, and antioxidative capacity.Significance and NoveltyThis study underscores the need for precise control in oat processing, crucial in plant‐based protein and novel food development for optimal quality and yield.

OAT GUM: STRUCTURE, PROPERTIES, PRODUCTION, APPLICATION IN THE FOOD INDUSTRY

Oat gum (β-glucan, glycan) belongs to the group of soluble dietary fibers. Due to their important functional properties, cereal β-glucans are used to reduce the level of cholesterol in the blood, alleviate the symptoms of diabetes, lower blood pressure, and prevent cardiovascular and oncological diseases. Sources of β-glucans are yeast, mushrooms, bacteria, barley, oats. The use of secondary resources of barley and oat processing as a source of β-glucans has both economic and environmental significance. Cereal β-glucans consist of β-D-glucose monomers connected by (1,3)- and (1,4)-glycosidic bonds. β-Glucan dissolves well in cold water and is insoluble in ethyl alcohol. It is able to form very viscous solutions at low concentrations. The viscosity of solutions depends on the concentration and molecular weight of β-glucan. The rheological properties of aqueous gum solutions do not depend on the pH of the medium. The presence of NaCl in concentrations of more than 0.5% leads to a decrease in the viscosity of solutions, and the addition of sucrose in the amount of 20-45% increases the viscosity. The technological features of obtaining β-glucans are related to the method of their extraction from natural sources. Extraction of oat gum from oat bran or rolled oats involves alkaline treatment of flour at 50-70 °C and pH 8.0-10.5, removal of starch and proteins, precipitation of oat gum with alcohol and separation by centrifugation. Solubility, degree of extraction, and yield of β-glucan from oats depend on particle size, pretreatment of grain raw materials, and extraction conditions (temperature, pH, extractants). β-Glucan is isolated from the extract by dialysis, ultrafiltration or alcohol precipitation. When using dialysis, highly viscous β-glucan is obtained, but with a lower yield; ultrafiltration and alcohol precipitation allow a higher yield of β-glucan with lower viscosity. Oat gum can be introduced into a wide range of food products to provide new functional properties and improve nutritional quality, includ ng wheat bread, bakery products, cookies, pasta, soft drinks, as a fat substitute in dairy and meat products. It performs the technological functions of a thickener, gelling agent, stabilizer or coating in food systems.

Common Wheat Pasta Enriched with Ultrafine Ground Oat Husk: Physicochemical and Sensory Properties.

Oat husk (hull) is a byproduct of oat processing that is rich in insoluble fiber. The aim of the study was to evaluate the effect of partially replacing wheat flour with oat husk (at levels of 0, 5, 10, 15, and 20 g/100 g) on the physicochemical properties and sensory acceptance of pasta. Additionally, UPLC-MS/MS analysis was performed to identify phenolic acids and flavonoid compounds, and the cooking properties of the pasta were evaluated. The test results indicate that oat husk significantly (p < 0.05) increased the ash and fiber contents in the pasta, while decreasing the protein and fat contents. Moreover, the redness and yellowness of both raw and cooked pasta increased, while lightness decreased as a result of pasta enrichment with oat husk. Oat husk also led to a decrease in the stretching force of cooked samples, although cooking loss increased significantly but did not exceed 8%. The contents of phenolics and antioxidant activity significantly increased with the incorporation of hull in pasta recipes. UPLC-MS/MS analysis showed that the enriched pasta was especially abundant in ferulic acid. Products with up to 10 g of husk/100 g of wheat flour showed good consumer acceptance. However, higher levels of this additive led to notably lower assessments, particularly in terms of pasta texture.

Oat and Oat Processed Products—Technology, Composition, Nutritional Value, and Health

Oat has been known in food technology and human nutrition for a very long time. Its rich chemical composition and high nutritional value make it of interest to scientists in the field of food processing technology as well as nutritionists. Low-processed, whole-grain oat products rich in biologically active substances with well-proven preventive and therapeutic effects include not only dehulled oat grains and groats but also a wide range of breakfast cereals. These products fit into the definition of functional foods and are considered excellent prebiotics. The continuous development of cereal processing technologies can improve existing cereal products and help to create new ones; however, it also increases the possibility of raw material over-processing, thus decreasing its functional properties. Therefore, monitoring technological progress and the quality of the products obtained is of great value and interest for nutritionists and consumers. The work presented here aims at systematizing existing knowledge on oat products, their impact on human health, and progress in oat processing technology. It also brings insight into various new avenues for the utilization of oat products in food technology.

Life-cycle assessment of yeast-based single-cell protein production with oat processing side-stream

Production of fish meal and plant-based feed proteins continues to increase to meet the growing demand for seafood, leading to impacts on marine and terrestrial ecosystems. Microbial proteins such as single-cell proteins (SCPs) have been introduced as feed alternatives since they can replace current fish feed ingredients, e.g., soybean, which are associated with negative environmental impacts. Microbial protein production also enables utilization of grain processing side-streams as feedstock sources. This study assesses the environmental impacts of yeast-based SCP using oat side-stream as feedstock (OS-SCP). Life-cycle assessment with a cradle-to-gate approach was used to quantify global warming, freshwater eutrophication, marine eutrophication, terrestrial acidification, land use, and water consumption of OS-SCP production in Finland. Dried and wet side-streams of oat were compared with each other to identify differences in energy consumption and transportation effects. Sensitivity analysis was performed to examine the difference in impacts at various locations and fermentation times. Benchmarking was used to evaluate the environmental impacts of OS-SCP and other feed products, including both conventional and novel protein products. Results highlight the importance of energy sources in quantifying the environmental performance of OS-SCP production. OS-SCP produced with dried side-streams resulted in higher global warming (16.3 %) and water consumption (7.5 %) than OS-SCP produced from wet side-streams, reflecting the energy and water requirements for the drying process. Compared with conventional products, such as soy protein concentrates, OS-SCP resulted in 61 % less land use, while exacerbating the environmental impacts in all the other categories. OS-SCP had more impact on global warming (205–754 %), water consumption (166–1401 %), freshwater eutrophication (118–333 %), and terrestrial acidification (85–340 %) than other novel products, including yeast protein concentrate, methanotrophic bacterial SCP, and insect meal, while lowering global warming (11 %) and freshwater eutrophication (20 %) compared with dry microalgae biomass.

Doses and application times of trinexapac-ethyl on the industrial quality of white oat grains

The application of trinexapac-ethyl in white oats, in addition to controlling lodging, can modify the architecture of the plant, which can favor good growth and development and the production of well-formed, large and heavy grains, characteristics that are valued by the food industry oat processing. However, the responses of the white oat genotypes regarding the effect of doses and times of application of the growth reducer can be variable. The objective of this work was to evaluate the effect of different doses and application times of the growth regulator trinexapac-ethyl on the industrial quality of white oat grains. The experiment was carried out with the cultivar IPR Artemis, under a randomized block design with four replications, in a 4 x 3 factorial scheme, corresponding to four doses of trinexapac-ethyl (0, 50, 100 and 150 g ha-1) and three application times (E1: plants with the 1st noticeable node; E2: between the 1st visible node and the 2nd noticeable node and E3: plants with the 2nd visible node and 3rd noticeable node). The weight of one thousand grains, hectoliter weight, percentage of grains with thickness greater than two millimeters, husking index and industrial grain yield were evaluated. The application of trinexapac-ethyl regardless of the stages at doses of 0 and 50 g ha-1 does not interfere with the industrial quality of grains, but at doses of 100 and 150 g ha-1, at times E2 and E3, there is a reduction in industrial quality of grains (weight of a thousand grains, hectoliter weight, percentage of grains thicker than two millimeters, hulling and industrial grain yield) of the cultivar IPR Artemis.

Distribution.β-Glucan, phenolic Acids. Oat Bran (Avena nuda) Processing. Oat Rice, Oat Flour

&lt;p&gt;Proportion, microstructure. oat bran, endosperm. analyzed. several selected typical cultivars. Naked Oat (Avena nuda).. Same time, distribution profiles.β-Glucan, phenolic acids. oat bran (pericarp, seed coat. aleurone layer), endosperm. tested. establish a method. determining. processing suitability. oats rice, oat flour. finally, method. used. verify. suitability. existing mainstream processing technologies. oat rice, oat flour. showed,. selected varieties,β-Glucan was mostly enriched in the bran containing a value of 85.7 mg/G, which was about 4.5 times higher than that in endosperm. Moreover, the contentsP-Coomaric acid and ferulic acid in oat bran were 0.099 and 1.00 mg/G, which were 24 and 48 times higher than thought in endosperm, review. In addition, the contentsP-Coomaric acid and ferulic acid in pericarp were 13 and 2.7 times higher than then in Testa + alonne layer, review. The average contentBeta-Glucan in the second bran obtained from Oat rice processing was 1.7%, Which was far lower than that in oat branBeta-Glucan in the fourth and fifth Brans obtained from oat flour processing were 6.73%And 7.80%, When were close to that in oat bran, suggesting the processing was intensive. In connection, by analyzing the contentsBeta-Glucan and phenol acids in the oat bran targeted by typing, we can determine the processing degree of oat products, which will provide technical support for oat processing.&lt;/p&gt;

Study results of rheological and baking parameters of dough from wholemeal bioactivated grain of hulless oats mixed with wheat flour

In order to improve the biological value of bakery products and consumer properties of new products, there are used the technological additives and functional ingredients, which include bioactivated hulless oats. The purpose of the current work was to estimate the physical, rheological, baking parameters of the dough mixtures obtained by mixing oat flour (wholemeal flour from bioactivated grain) with high-quality premium wheat flour according to the farinographic results and baking analysis. There has been experimentally established that the indicators characterizing the behavior of the dough varied depending on the type of ingredients (wholemeal grain before and after bioactivation) and the proportion of oat processing products (10, 20 %) in the composite mixtures. Dough resistance has de­creased on 3.0–7.0 min to wheat flour, valorigraphic estimation at 19–40 u.v. and dough dilution increases significant on 60–160 u.f. The physical properties of the dough when used in mixtures of bioactivated grains slightly have dete­riorated compared to non-bioactivated grains: dough resistance and valorigraphic estimation reduced on 0.5–1.0 min and 1–7 u.v., respectively, except for the dough dilution, which improved on 22.0–29.0 %. These processes can be explained by the very high amylolytic activity of the grain after germination. During the trials, there was found an ad­vantage in the general baking assessment in the options using bioactivated oat grain, even though the farinograph recorded a slight deterioration in the physical parameters of the dough. Volume yield was 425–625 cm3 (420–563 cm3 with non-bioactivated grain) and a baking assessment of 2.6–4.4 points versus 2.7–4.3 points. Volume yield increase and baking quality improvement in this case can be explained by the effect of the compensation ability of the mixing strength of wheat. The studied hulless oat varieties ‘Baget’ and ‘Bekas’ in comparison with the chaffy variety ‘Konkur’ in mixtures have shown the best values characterizing the physical properties of the dough and baking quality. They possess better advantage in dough resistance on 1.0–3.0 min., dough dilution on 10–40 u.f. and valorigraphic estimation on 4–17 u.v. They produced 625 cm3 of maximum volume yield, their baking assessment was 4.4 and the tendency remains the same after bioactivation of oat grain.

Effect of industrial processing on the volatiles, enzymes and lipids of wholegrain and rolled oats

The aim of this research was to study the effect of industrial processing stages (kilning, cutting, steaming, rolling and packaging) on the enzymes (lipase and peroxidase), lipids and volatiles of wholegrain and rolled oats. Chemometric data analysis was used to assess the evolution of flavor-related compounds, investigate the relationships between the attributes and select discriminant marker compounds. Oat groats (dehulled oat grain) had significantly (p < 0.05) higher lipase and peroxidase activities, and possessed higher amounts of short-chain volatile fatty acids than the processed oats. The combined effect of kilning and subsequent steaming significantly (p < 0.05) reduced the activity of these enzymes. The use of high temperatures during kilning and steaming triggered the Maillard reaction and Strecker degradation reactions, leading to the formation of odor-active volatile compounds, such as pyrazines, furans and Strecker aldehydes. These compounds are commonly associated with the desirable nutty and toasted aroma of oat-based products. Overall, this study successfully identified key volatile markers and their associated reaction pathways, which can be used to control and optimize the industrial oat processing steps.

Cultivation of seaweeds in food production process waters: Evaluation of growth and crude protein content

There is an increasing demand for sustainably produced, protein-rich, and nutritious food. Seaweeds are promising protein sources for the future if their protein content can be optimized, something which can be achieved by cultivation in elevated nutrient concentrations. Cultivation of seaweeds in integration with fish farms have received much attention lately, but using nutrient-rich process waters from other food industries as feed stock for seaweed has rarely been studied. Here, we demonstrate a simple and sustainable strategy to answer the increasing world demand for food rich in plant-based proteins by connecting food production process waters with seaweed cultivation. We compared growth rates and crude protein content of four different seaweed species, the brown species Saccharina latissima, and the green species Ulva fenestrata, Ulva intestinalis, and Chaetomorpha linum, when cultivated in two dilutions (providing 20 and 200 μM ammonium) of eight different process waters emerging from recirculating salmon aquaculture systems as well as from herring, shrimp and oat processing. Growth rates of the green seaweeds were up to 64% higher, and crude protein content was almost up to four times higher when cultivated in the food production process waters, compared to seawater controls. Growth rates were generally higher in presence of 20 μM compared to 200 μM ammonium, while crude protein content was either unaffected or positively affected by the increasing ammonium concentration. This study indicates the potential for cultivating seaweeds with food production process waters to generate additional protein-rich biomass while nutrients are being circulated back to the food chain. A new nutrient loop is thus illustrated, in which the costly disposal of food production process waters is instead turned into value by seaweed cultivation.

Study on the effects of combined processing of micro‐pulverization and extrusion on the physicochemical properties of oat bran

The utilization rate of oat bran was improved and wastage of resources was reduced using the micro-pulverization technology combined with extrusion in processing oat bran. The effects of micro-pulverization and extrusion treatment on the structure, color, physical and chemical properties, functional properties, and pasting properties of oat bran were evaluated via Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), colorimeter, and rapid viscosity analyzer (RVA). Results showed that the pulverization and extrusion did not produce new functional groups in the bran. However, both treatment methods could increase the content of soluble dietary fiber (SDF) and degree of starch gelatinization, reduce oil-holding capacity (OHC), and increase water solubility index (WSI). Micro-pulverization increased the brightness and slowly digestible starch (SDS) of the bran, reduced rapidly digestible starch (RDS), and enhanced the antioxidant capacity of oat bran. Conversely, extrusion reduced the brightness and antioxidant capacity of oat bran, increased RDS. And extrusion made the surface of the bran relatively flat and denatured the protein. This study provides a theoretical basis that enterprises involved in oat processing can refer to. According to different market needs, adopt appropriate processing methods to process oat bran in order to gain more oat bran products.

Nutritional composition and physicochemical properties of oat flour sieving fractions with different particle size

Nutritional constituents, hydration, pasting, and thermal properties of oat flour sieve fractions (74–180 μm) and the relationship between composition and characteristics were studied. Starch constituents, protein components (except for albumins), and saturated fatty acids (SFA) were mostly distributed in small particle fractions, while total protein, albumin, dietary fiber (DF), lipids, and unsaturated fatty acids (UFA) were abundant in large particle fractions. Amino acids (except for Tyr and Gly) of group Ⅰ, Ⅱ, and Ⅲ were significantly lacking in S2 (150–180 μm), and Cys decreased from 2.51% to 1.50% with the decrease in sieving particle sizes. The largest particles showed the highest water solubility index (WSI, 9.90%), the medium particles (100–132 μm) exhibited the highest pasting viscosities (final viscosity of 4148 cP), and the smallest particles had the maximum gelatinization enthalpy (ΔH, 3.2 J/g). Correlation analysis demonstrated that except for the basic components, Glu, Cys, Iso, Phe, C16:0, C18:0, and C18:2n6c also significantly affected the WSI and pasting properties of oat flour, while amylose, Gly, Ala, Val, Met, and C20:1 were highly correlated with thermal properties. The results are useful for oat processing and the development of oat-based products with specific particle size range to achieve desirable characteristics.

Micronized Oat Husk: Particle Size Distribution, Phenolic Acid Profile and Antioxidant Properties.

Oat husk (OH; hull) is a by-product generated from oat processing and is rich in insoluble fibre and phenolic compounds. The aim of this work was to study the particle size distribution, antioxidant activity, and phenolic profile of micronized OH. For this purpose, the hull was first sterilized using superheated steam and was then ground using an impact classifier mill. The particle size distribution (PSD) of the ground husk was determined using the laser diffraction method and the parameters characterizing the PSD of the ground husk, and its antioxidant activity were calculated. In addition, UPLC-MS/MS analysis of phenolic acids was also performed. Micronization of the sterilized husk effectively decreased the size of the particles, and with the increasing speed of the rotor and classifier, the median size of the particles (d50) decreased from 63.8 to 16.7 µm. The following phenolic acids were identified in OH: ferulic, caffeic, p-hydroxybenzoic, vanillic, syringic, and synapic acid. Ferulic acid constituted about 95% of total phenolic acids. The antioxidant activity of the obtained extracts increased as the particle size of the micronized husk decreased. The highest half maximal inhibitory concentration (EC50 index) was found for chelating power, and the lowest was found in the case of radical scavenging activity against DPPH.

Heat-induced reduction of deoxynivalenol and its modified forms during flaking and cooking of oat

Deoxynivalenol (DON) and its modified forms deoxynivalenol-3-glucoside (DON-3G) and 3-acetyl-deoxynivalenol (3-ADON) are common contaminants in Norwegian oats. In order to provide more information about the fate of these mycotoxins during oat processing, the levels of DON, DON-3G, 3-ADON and the sum of them (total DON) were determined using LC-HRMS/MS at different processing steps. Oat groat was softened by either steaming or conditioning, rolled into flakes of two thicknesses, and subsequently cooked to produce flake porridges. Flour of oat groat (untreated or kilned) was cooked to flour porridges. The flaking process had major effect on the mycotoxin levels in resulting flakes, with significant impact for type of softening regime, but not for flake size. Steam-softening caused the largest reduction of DON, DON-3G and total DON in flakes, retaining 41, 60 and 46%, respectively, compared to oat groat. In contrast, 3-ADON in flakes was most reduced by conditioning, to 29% of the levels in oat groat. Cooking to porridge from flakes did not result in any additional mycotoxin reduction, though significant impact of flake size was shown in the final porridges, with highest reduction of total DON in the porridges originating from steamed thick flakes. Cooking porridge from untreated oat flour gave significant reduction in mycotoxin levels, however not for kilned oat flour which had already undergone reduction during kilning. In conclusion, the study shows that processes involving heat-treatment, i.e. kilning, steaming or cooking, efficiently reduced total DON in oats during flaking and porridge cooking, and reduction is dependent on previous processing steps.

A Systematic Review and Meta-Analysis of Randomized Controlled Trials on the Effects of Oats and Oat Processing on Postprandial Blood Glucose and Insulin Responses

Oats are a whole grain cereal with potentially favorable effects on the postprandial glycemic response; however, the effects of oat processing on these glycemic benefits are not well understood. The study objective was to determine the effects of differently processed oats on the postprandial blood glucose and insulin responses relative to refined grains. Eleven electronic databases were systematically searched to identify studies published up to and including May 2019. Randomized controlled trials comparing the postprandial blood glucose and insulin responses to oats compared with any refined grain were included, so long as the available carbohydrate content of the test meals was similar. Pooled effect sizes were computed using the difference in incremental area under the curves for blood glucose and insulin following the consumption of oats compared with the refined grain control. Ten publications were included, with intact oat kernels studied in 3 comparisons, thick oat flakes (>0.6 mm) in 7 comparisons, and thin/quick/instant oat flakes (≤0.6 mm) in 6 comparisons. Compared with the consumption of the refined grain control, the consumption of intact oat kernels was associated with significant reductions in postprandial blood glucose (-45.5 mmol x min/L; 95% CI: -80.1, -10.9 mmol x min/L; P=0.010) and insulin (-4.5 nmol x min/L; 95% CI: -7.1, -1.8 nmol x min/L; P=0.001) responses; the consumption of thick oat flakes was associated with significant reductions in postprandial blood glucose (-30.6 mmol x min/L; 95% CI: -40.4, -20.9 mmol x min/L; P<0.001) and insulin (-3.9 nmol x min/L; 95% CI: -5.3, -2.5 nmol x min/L; P<0.001) responses; but, the consumption of thin/quick/instant oat flakes was not associated with any effects on the postprandial blood glucose and insulin responses. A disruption in the structural integrity of the oat kernel is likely associated with a loss in the glycemic benefits of oats.

Topdressing nitrogen fertilization associated with trinexapac-ethyl on industrial quality of oat grains

Nitrogen fertilization, besides increasing productivity, can favor the production of well-formed, large, and heavy grains, which are traits valued by the oat processing industry. However, high nitrogen (N) doses may lead to plant lodging, which could be solved by using growth retardant. This study aimed to evaluate the industrial quality of white oat grains cultivated under different nitrogen doses and associated with the growth retardant trinexapac-ethyl in two growing environments. Experiments were conducted in Londrina and Mauá da Serra, PR, Brazil, using the cultivar IPR Afrodite in a randomized block design in a 4 × 2 factorial scheme and four replications. Treatments consisted of four topdressing N doses (0, 30, 60, and 90 kg ha−1) and the application or not of growth retardant. Thousand-grain weight, hectoliter weight, grain index greater than two millimeters, peeling index, and industrial grain yield were evaluated. The effect of N fertilization and growth retardant on the industrial quality of white oat grains depends on the characteristics of the growing environment. The trinexapac-ethyl application reduces grain quality in Londrina and Mauá da Serra. However, the industrial quality of grains is high in both growing environments when the growth retardant is associated with nitrogen doses.

PECULIARITIES OF NAKED OAT GRAIN AS A CEREAL CULTURE

Archaeological excavations show that oats were known as early as the Bronze Age, from about 1500-1700 BC. According to various historical data, the homeland of the oat culture forms is Southern Europe, Northeast China and Mongolia. The first archeological findings of oat grain were discovered in Germany and date back to the I-VI c. In Kievan Rus oats began to grow from about the VI. For many centuries, oats have been an important feed and foof grain,and with the beginning of the twentieth century there is an increase in its use in agriculture and processing. Widespread products of oat processing in different countries of the world are groats, cereals, flour and food bran, in addition to traditional products produce instant cereals, muesli, various intended semi-finished products. Oats are also widely used in other industries: it is additionally used in the production of beer, oat milk, ice cream, bread, cookies, baby food, etc. In Ukraine, oats are grown mainly as ancillary technical culture. The area of crops is from 5000 to 6000 km2. The main production is concentrated in Polissia and Forest-Steppe, mainly spring oats are grown, to a lesser extent semi-winter and winter forms. According to the State Statistics Service of Ukraine, the gross grain harvest in the last 5-7 years has increased and is at the level of 458 ... 616 thousand tons of grain per year. Over the past 20 years, oat production in Ukraine has been declining, due to the fact that most of it is grown for cereals, with a relatively small crop yield and high cultivation costs, even with the use of state-of-the-art agrotechnology. About 60,000 tonnes of oats are used annually to meet the needs of the domestic groats industry. Breeders have received new grains that have increased nutritional and technological value. Considering new varieties of oats, it is possible to distinguish naked forms of Avena nuda (naked oats). In the world, naked oats is a valuable crop that has a consistently high nutritional value that allows it to be used in various industries. This type of oat is derived by the method of individual selection from a cross-hybrid population. The variety of this oat is inermis, morphologically different from the hull varieties by the structure of the spikelets, which determines the peculiarities of its quantitative and qualitative indicators The peculiarity of naked oats is the absence of flower hulls firmly bound to the grain surface (20 ... 40% in oat hulled forms), which significantly improves its properties. The hulls in the naked varieties are soft, do not cover the grain very tightly and are almost completely separated in the process of grain harvesting and threshing.

Biorefining Oat Husks into High-Quality Lignin and Enzymatically Digestible Cellulose with Acid-Catalyzed Ethanol Organosolv Pretreatment

Oat husks are low-value lignocellulosic residues of oat processing that carry an environmental impact. Their polymers (cellulose, hemicellulose, and lignin) can be converted into a wide variety of value-added products; however, efficient pretreatment methods are needed that allow their fine separation for further tailored valorization. This study pioneered the use of milling-free and low acid-catalyzed ethanol organosolv for the delignification of oat husks, allowing their conversion into three high-quality streams, namely, glucan-rich, lignin-rich, and hemicellulosic compound-rich streams. Temperature, retention time, and solid-to-liquid ratio were found to impact the delignification of oat husks when using a one-factor-at-a-time strategy. The ideal conditions that were found (210 °C, 90 min, and solid-to-liquid ratio of 1:2) culminated into glucan and lignin fractions containing 74.5% ± 11.4% glucan and 74.9% ± 7.6% lignin, respectively. These high-purity lignin fractions open the possibility for higher value applications by lignin, potentially impacting the feasibility of second generation biorefineries. The glucan fraction showed 90% digestibility after 48 h of hydrolysis with 10 filter paper units of enzyme cocktail per gram of glucan. Considering the absence of size reduction and high solid loading, together with the quality of the obtained streams, organosolv pretreatment could be a potential strategy for the valorization of oat lignocellulosic residues.

Impact of oat processing on glycaemic and insulinaemic responses in healthy humans: a randomised clinical trial.

Oats can be processed in a variety of ways ranging from minimally processed such as steel-cut oats (SCO), to mildly processed such as large-flake oats (old fashioned oats, OFO), moderately processed such as instant oats (IO) or highly processed in ready-to-eat oat cereals such as Honey Nut Cheerios (HNC). Although processing is believed to increase glycaemic and insulinaemic responses, the effect of oat processing in these respects is unclear. Thus, we compared the glycaemic and insulinaemic responses elicited by 628 kJ portions of SCO, OFO, IO and HNC and a portion of Cream of Rice cereal (CR) containing the same amount of available-carbohydrate (23 g) as the oatmeals. Healthy males (n 18) and females (n 12) completed this randomised, cross-over trial. Blood was taken fasting and at intervals for 3 h following test-meal consumption. Glucose and insulin peak-rises and incremental AUC (iAUC) were subjected to repeated-measures ANOVA using Tukey's test (two-sided P&lt;0·05) to compare individual means. Glucose peak-rise (primary endpoint, mean (sem) mmol/l) after OFO, 2·19 (sem 0·11), was significantly less than after CR, 2·61 (sem 0·13); and glucose peak-rise after SCO, 1·93 (sem 0·13), was significantly less than after CR, HNC, 2·49 (sem 0·13) and IO 2·47 (sem 0·13). Glucose iAUC was significantly lower after SCO than CR and HNC. Insulin peak rise was similar among the test meals, but insulin iAUC was significantly less after SCO than IO. Thus, the results show that oat processing affects glycaemic and insulinaemic responses with lower responses associated with less processing.