Marcin Mitrus

This study aimed to produce gluten–free extruded instant products based on corn and corn–buckwheat blends in a 75:25 and 50:50 mass ratio, respectively, processed at moisture levels of 12, 14, 16, and 18% and at screw rotation speeds of 80, 100, and 120 rpm. In this study, the extrusion–cooking process stability was determined, including energy consumption and efficiency. Additionally, physical properties of extrudates were determined, including density, color, the volumetric gel index, the water absorption index, the water solubility index, and dynamic viscosity. It was shown that increasing the extruder screw speed results in increased process efficiency and energy consumption and properties (gelling ability, water solubility, and a decrease in water absorption, density and yellowness) of the final product. With increasing moisture content, increased bulk density, volumetric gel index, water absorption, and redness and yellowness values and a decrease in solubility were observed. Increasing the buckwheat content resulted in increased efficiency, water absorption, red tint, and dynamic viscosity. However, the opposite observations were noted for bulk density, gel formation, lightness, and yellowness of extrudates. The results showed the extrusion–cooking processing is an appropriate and easy-to-use method for the modification of corn–buckwheat blends and the preparation of innovative products.

This study investigated the effects of drying methods, namely freeze-drying and vacuum-drying, and heating plate temperature (20 °C, 40 °C, and 60 °C) on the drying kinetics, specific energy consumption, proximate chemical composition, colour, peroxide value, pH and cutting force of beef eye of round muscle, pork loin, and chicken fillet. Drying time ranged from 360 min for pork loin freeze-dried at 60 °C to 1050 min for beef eye of round muscle vacuum-dried at 20 °C, and freeze-drying was generally faster than vacuum-drying at the corresponding temperature settings. Among the tested models, the logarithmic model provided the best fit to changes in the moisture ratio, with R² values of 0.9972–0.9997 and RMSE values of 0.0053–0.0151. Increasing the drying temperature reduced the specific electrical energy consumption per kilogram of dried product in both drying methods, which was associated with shorter drying times at higher temperatures. Fat and protein contents did not differ significantly in products dried at 20 °C and 40 °C, but decreased at 60 °C, reaching 8.85–12.26 g/100 g d.m. and 76.16–79.86 g/100 g d.m., respectively. Drying also affected lipid oxidation and pH. At 20 °C and 40 °C, changes in peroxide value were moderate, whereas at 60 °C lipid oxidation markedly increased, especially in chicken meat and vacuum-dried samples. Both drying methods reduced pH compared with the raw material, with the greatest decrease observed at 60 °C, particularly after vacuum-drying. The highest L* value among dried samples was recorded for chicken fillet freeze-dried at 20 °C (85.44), whereas the lowest was observed on the surface of beef eye of round muscle vacuum-dried at 60 °C (41.98). Increasing temperature decreased lightness and redness but increased yellowness and cutting force. Cutting force ranged from 35.7 N for chicken fillet freeze-dried at 20 °C and cut across the fibres to 231.4 N for beef eye of round muscle vacuum-dried at 60 °C and cut along the fibres. These results indicate that the drying method and temperature strongly affect the quality attributes of dried meat and should be selected according to the desired product characteristics. Future studies should focus on the optimisation of drying parameters for specific meat types and include a broader quality assessment, particularly microbiological safety and sensory properties.

Industrial almond by-products (ABPs, almond oil cake) and tomato by-products (TBPs, mixture of peel and seeds) are nutrient-rich residues that could enhance the nutritional value of gluten-free pasta and support sustainable waste reduction. This study investigated the impacts of ABP or TBP incorporation and the extrusion screw speed on rice-based pasta quality. Rice pasta (control) and pasta enriched with ABP or TBP at different rates (2.5%, 5.0%, 7.5% and 10.0%) were processed by extrusion-cooking at two screw speeds (50 and 90 rpm), and their quality (cooking loss, water absorption capacity, hardness, firmness, adhesiveness and color) was evaluated, as well as energy requirements during processing (specific mechanical energy (SME)). The results showed that an increase in the ABP and TBP rates had a more pronounced positive effect on cooking loss, water absorption capacity, yellowness and redness values. Moreover, comparable hardness and firmness, but lower adhesiveness values, were recorded in cooked rice–ABP-enriched pasta. However, cooked pasta enriched with TBP had lower hardness than the control pasta. Regarding energy consumption, pasta processed with a higher by-product rate at a higher screw speed showed similar SME as compared to the control pasta. In this regard, ABP can be used successfully from 7.5 to 10.0% in rice–ABP pasta formulations without compromising its technological properties. However, the optimization of the additive rate of TBP requires further study.

The study investigates the impact of sourdoughs made with different flours (white wheat, wholemeal wheat, and barley) and specific enzymes (laccase, lipase, and hemicellulase) on the technological properties of gluten-based wheat breads, thereby exploring the combined role of sourdough and enzymes. Three levels of each sourdough (20, 30, and 40%) were tested, and the optimal level was then used to evaluate the impact of individual and combined enzyme treatment. Pasting properties and FT-IR analyses of the flours were evaluated. White wheat flour displayed the highest peak viscosity (353.50 mPas) and final viscosity (526.50 mPas). β-sheet structures predominated in all samples, although they were most prevalent in wholemeal wheat flour (51%) as opposed to white wheat flour (47%) and barley (47%). Sourdough breads exhibited better texture and moisture retention at 40% inclusion than at other levels. After 72 h, white wheat sourdough maintained the highest specific volume (3.71 cm³/g), while barley sourdough retained the most moisture (38.83%) and the lowest chewiness and hardness results, suggesting better softness and crumb retention. Whereas for enzyme treatment, they had different effects. White wheat and wholemeal wheat sourdough breads treated with enzymes had decreased hardness, chewiness, and gumminess; barley sourdough breads with enzymes were negatively affected by the texture. Correlations and multivariate analysis reveal that bread texture is strongly influenced by the type of sourdough and enzymatic treatment. Higher doses of laccase or hemicellulase improve softness in wholemeal-based sourdough bread, while excessive lipase leads to a firmer and less pleasant crumb.

This study explores the application of three fermented plant materials—wheat, acorns, and sorghum—in couscous preparation, as well as their impact on its properties. A survey was conducted in some localities in Algeria. The aim is to reproduce the diagrams for the manufacture of different types of couscous incorporated with fermented materials and to evaluate the pasting properties, culinary qualities, and microstructure of each type of couscous produced. The survey identified four couscous formulations made with durum wheat semolina: couscous 1 (4% sorghum, 4% wheat, 8% acorns), couscous 2 (8% acorns), couscous 3 (0.8% sorghum, 6% acorns), and couscous 4 (4% wheat, 4% acorns). A comparative study of the four types of couscous showed significant differences in their physicochemical and microstructural properties. Formulations C3 and C4 showed the best functional performance among all the couscous samples studied. In terms of the swelling index, measured at 25 °C and 95 °C, C3 reached 131.11% and 165.55%, respectively, while C4 recorded 124.9% and 157.0%. Furthermore, these two formulations had the highest viscosity values: initial viscosity of 25 mPas (C3) and 27 mPas (C4), maximum viscosity of 31 mPas (C3) and 30 mPas (C4), and final viscosity of 49 mPas (C3) and 46 mPas (C4). Analysis of the cooking loss revealed higher values for couscous 1 and 2. The microstructure of couscous 2 revealed the presence of native starch particles, open porosity, and a state of partial gelatinization. The study revealed that formulations C3 and C4 significantly (p < 0.05) impact couscous structure by enhancing functionality while preserving quality. It also maintained ancestral knowledge and offered valuable insights for future industrial applications.

The aim of the research was to evaluate the influence of the forming die openings shape on processing parameters of the extrusion-cooking process and on the selected properties of gluten-free crisps. The experiment used blends of corn grits, unroasted buckwheat, rice, and dried blackberries. The extrusion process of gluten-free crisps was carried out via a prototype EXP-45-32 single-screw extruder with L/D=16. During the tests, 5 different forming dies were assessed: 2 openings with a diameter of 2 mm each, 1 round opening with a diameter of 3 mm, 1 cross-shaped opening, a star and a heart. During the tests, the processing efficiency and energy consumption of the extrusion process were tested, and the expansion index, bulk density and hardness of the crisps were investigated. The research demonstrated that the forming die shape affects the efficiency and energy consumption of the extrusion-cooking process of crisps. The lowest efficiency was found if a heart-shaped die was used, and the highest efficiency was determined in the case of a star-shape die. Moreover, the highest specific energy consumption was noted when using a star-shaped die during crisps extrusion. Crisps obtained using dies with larger diameters were characterized by a lower expansion index. The complicated shape of the die opening resulted in less expansion of the obtained crisps. The highest bulk density and hardness were found in the case of crisps obtained on a star-shaped forming die.

The therapeutic potential of broccoli has been highlighted by its function in the prevention of cancer, diabetes and other diseases. As a result, there is a great deal of interest in creating innovative functional foods supplemented with broccoli. In the extrusion-cooking process, raw materials based on potato mixes with the addition of fresh broccoli (Brassica oleracea L. var italica, Brassicaceae) were used to create new generation extruded snack pellets. A prototype single screw extruder-cooker with L/D=20 was utilized, and various processing conditions (screw speed 60 and 100 rpm, as well as either 32 and 36% levels of initial moisture content) were applied. Mixtures of 10% and 30% fresh broccoli contents were investigated. The final snack pellets obtained under such processing conditions were determined for their antioxidant potential, polyphenols, proximate composition and fatty acids profile. We found that in the presence of fresh broccoli in blends, higher screw speed and higher moisture content allowed obtaining (in most samples) a higher polyphenal content in the resulting pellets. Over all, the antioxidant potential of snack pellets increased with the addition of fresh broccoli. Pellets with 30% addition of the broccoli processed at screw speed 100 rpm at moisture content of 32% displayed the highest total polyphenols content and highest antioxidant activity. Moreover, such samples demonstrated notable increase in the content of total protein, crude ash, as well as MUFA and PUFA in the total amount of fatty acids.

New types of extruded snack pellets of wheat-corn blend base and fresh lucerne sprouts were devel-oped. The aim of the study was to examine the effect of fresh lucerne sprouts addition on the water consumption, processing efficiency and the specific mechanical energy during production of...

The aim of the study was to evaluate selected properties of potato snack pellets fortified with fresh kale addition. Varying levels of fresh kale (10, 20 and 30%) were added in order to obtain a new type of fortified snack pellet as a semi-fini-shed product for further expansion and their effects...

The aim of the study was to develop a suitable recipe for wheat-corn snack pellets fortified with insect flour addition and to evaluate the relevant processing aspects and physical characteristics of the developed products. Varying levels of edible insect flour (10, 20, and 30%) were incorporated into a new type of fortified snack pellet as a half product for further expansion. The effects of the edible insect flour level, as well as processing variables (moisture levels 32, 34, 36% and screw speeds 60, 80, 100 rpm), were analyzed on the extrusion stability and on selected snack pellets’ physical properties processed via single-screw extrusion cooking. This research indicated that an increasing amount of edible insect flour significantly affected the processing output and energy consumption. The incorporation of insect flour in blends significantly increased the specific mechanical energy and efficiency of pellet extrusion, especially at a high moisture level and high screw speed during processing. Moreover, the addition of insect flour in the snack pellets significantly reduced the bulk density and pellet durability. Principal component analysis confirmed that approximately 76.5% of the data variance was explained by the first two principal components, and significant correlations were noted between the properties of the tested snack pellets. It can be concluded that up to 20% of insect flour in newly developed extruded snack pellet formulations has no negative effect on processing and physical properties.