Extrusion Characteristics Research Articles

Standardization and evaluation of RTE extruded corn-pearlmillet snacks incorporated with kidney bean or green gram flour: A comparative study

The presentstudy aimed to develop ready-to-eat extruded snacks by incorporating kidney bean flour (0-25%) or green gram flour (0-25%) in a cornpearlmillet (70:30) flour blend. All flours were tested for their compositional and nutritional parameters (crude fibre, carotenoid, phyticacid, polyphenols, iron, zinc, and total dietary fibre). Evaluation of pasting characteristics, water absorption, and dough extensibility of flours and physical (bulk density, expansion ratio, sectional expansion index, and hardness) and sensory properties of extruded snacks weredone. The addition of pulses reduced pasting values, resistance to extension, and extensibility of flour while increasing water absorptions significantly (p<0.05). Physical properties and sensory characteristics of extrudates were also significantly (p<0.05) reduced by pulses addition. However, considering nutritional aspects, kidney bean flour up to 15% or green gram flour up to 10% is recommended to be incorporated for obtaining extrudates of desirable quality. Both pulses hadsimilar effects on product quality, but the use of green gram flour is preferred over kidney bean due to its minimum anti-nutritional factors available in the resulting product.

Sugar inclusion influences the expansion characteristics of corn starch extrudates.

Corn starch-based direct expanded products incorporated with 2% and 10% (w/w) sugar (fructose, glucose, sucrose, and xylose) were produced using a 20mm co-rotating twin-screw extruder. The pasting and thermal properties of raw corn starch-sugar mixes were analyzed before extrusion processing. The independent variables for extrusion processing included two sugar inclusion levels (2% and 10% w/w) and two screw speeds (150 and 250rpm). The extrudates were characterized by their initial expansion ratio (IER), expansion ratio (ER), and shrinkage. ER values were high for fructose at 2% and 150rpm and 10% glucose and sucrose extrudates at 250rpm. The extrudates with 2% sucrose inclusion shrunk significantly higher than the control. Fourier transform infrared (FTIR) spectroscopy of the extruded blends did not indicate the presence of any new covalent bond formed between starch and sugar post-extrusion. The interactions between sugar concentration and screw speed significantly influenced extrudate expansion characteristics. Due to their thermal and plasticizing properties, sugar inclusion (glucose, fructose, sucrose, and xylose) enhanced the extrudate expansion by altering their melt viscosity. PRACTICAL APPLICATION: The findings of this study can improve the expansion characteristics of high-fiber-based extruded snacks. Ingredients high in fiber generally hinder the starch transformation during extrusion and negatively impact the expansion properties. The presence of sugar at low concentrations can improve melt properties during extrusion processing and, in turn, significantly improve the textural properties of snacks.

High moisture extrusion of pulse proteins: Texture, structure, and in vitro digestion characteristics of extrudates

Pulse proteins are promising components for plant-based food development, yet their diverse subunit compositions, influenced by source origin, result in variable extrusion properties. This study utilized high moisture extrusion (60% moisture content) to prepare extrudates from four pulse proteins: soy, pea, chickpea and mung bean protein isolates (SPI, PPI, CPI, and MPI, respectively). The texture, structure, and in vitro digestion characteristics of extrudates were examined. The results showed that SPI and PPI were mainly composed of 7S and 11S globulins, while CPI and MPI were mainly composed of 7S globulins, and 11S globulins, respectively. SPI extrudates exhibited significantly lower hardness, chewiness, and transverse and longitudinal fracture stresses, while CPI extrudates exhibited a higher anisotropy index. SPI extrudates with a higher β-sheet content (39.08%) exhibited denser structures. The gastrointestinal digestibility (86.65%) of CPI extrudates was higher than other groups. Correlation analysis showed that 7S/11S ratio was positively correlated with the melt viscosity, while negatively correlated with the anisotropy index and in vitro digestibility. This study highlights the distinct extrusion properties of pulse proteins based on their unique subunit composition. The results provide insights for selecting appropriate protein sources and developing plant-based protein products with tailored textural attributes and desirable digestibility.

Field Cricket (Gryllus bimaculatus) and Spirulina (Arthrospira platensis) Powders as Environmentally Friendly Protein Enrichment Ingredients in Corn Snacks.

Unconventional protein sources are currently extensively studied as food ingredients. This study aimed to evaluate the effect of 1.5% and 3% field cricket powder (GB) and 2-8% of its mixture (1:1) with spirulina powder (S) on the nutritional value, physicochemical properties, and sensory characteristics of corn extrudates. Additionally, 2% baking powder (BP) was added to assess its impact on the properties of the enriched extrudates. The results showed that both GB and GB + S improved nutritional value, with protein content increasing by up to 46% and higher levels of essential amino acids, particularly leucine and valine. However, these ingredients decreased the expansion ratio (by up to 15%), colour lightness (by up to 30%), and yellowness (by up to 47%) and increased the hardness (by up to 25%) of the corn extrudates. The S addition positively influenced product storage stability but decreased its sensory acceptance, especially aroma and taste. The BP addition mitigated the negative effects of higher GB and GB + S concentrations, particularly on sensory characteristics. In conclusion, incorporating up to 6% of the GB + S mixture provides a higher protein content with only minor changes to the product's characteristics compared to GB. Ratings exceeding 4.2 points indicate the good acceptability of these snacks.

Elucidating the mechanism of inulin-induced improvement in the structural and functional properties of High-moisture extruded products

High-moisture extrusion (HME) has increasingly garnered attention in the production of plant-based meat analogs. Nevertheless, the disorganized structural properties and poor functional characteristics of HME extrudates pose significant challenges to the advancement of plant-based alternatives in the food industry. The coextrusion of proteins and polysaccharides has emerged as an effective strategy to improve the sensory qualities of HME meat analogs. Herein, we investigated the effects of the type and addition of inulin on the structural and functional properties of HME extrudates comprising soy protein isolate, soy protein concentrate, and wheat protein. The results indicated that inulin facilitated the conversion of 7S to 11S globulin and induced a transformation from a β-turn angle to a β-folded protein structure, promoting lamellar structure formation and enhancing the overall stability of the protein matrix. Optimal results were achieved with the addition of 6% long-chain and short-chain inulin. In terms of functional characteristics, the incorporation of short-chain inulin resulted in a superior fiber structure and protein digestibility, whereas long-chain inulin enhanced the water-holding capacity, rehydration rate, and thermal stability. Additionally, intermolecular interaction analysis revealed that these inulin-induced improvements in the quality of HME extrudates are primarily attributed to the strengthening of disulfide bonds and hydrogen bonds. These findings offer crucial insights for advancing the quality of plant-based meat analogs, providing valuable directions for future product development in the food industry.

The interplay between soy proteins and dietary fiber in determining the structure and texture of high moisture extrudates

The (joint) contribution of soy proteins and dietary fibers (DFs) in determining the structure and texture of high moisture extrudates remains largely unclear. Blends of soy protein isolate (SPI) and a soy DF-enriched fraction (SDF) were prepared in different ratios, and their bulk rheology and water mobility distribution when hydrated to 60% moisture were related to the structure, texture, and protein extractability of high moisture extrudates prepared at the same moisture level. Increasing the DF proportion in hydrated SPI-SDF blends resulted in higher storage and loss moduli in linear region. In the non-linear region, however, higher DF levels resulted in more viscous behavior. The mobility of weakly interacting water protons decreased in samples with more DF. High moisture extrudates made from SPI had a layered microstructure consisting of V-shaped lamellae. Extrudates prepared from a blend containing 25% DF had more fibrous appearance with thin, branched protein-rich lamellae. Extrudates containing 52% DF exhibited a macrostructure without the presence of distinct layers or fibers and lacked a continuous protein network in their microstructure. The contribution of disulfide bonds to sustaining the protein network increased in extrudates containing more DF. Extrudates containing more DFs had lower cutting strengths and anisotropic indices. Strong negative correlations were found between the phase angle (obtained at 95 °C) in the non-linear region of the hydrated blends (indicating the relative importance of the viscous response) and the cutting strength of the extrudates in both longitudinal (R = −0.759) and perpendicular (R = −0.883) directions to the flow. In conclusion, the ratio of soy protein to DF had a significant impact on the characteristics of high moisture extrudates, which were associated with alterations in rheological properties, water mobility distribution and protein extractability.

Understanding the mechanism for sodium tripolyphosphate in improving the physicochemical properties of low-moisture extrusion textured protein from rapeseed protein and soybean protein blends

Our previous experiments found that rapeseed protein (RP) has applicability in low-moisture textured proteins. The amount of RP added is limited to <20 %, but the addition of 20 % RP still brings some negative effects. Therefore, in order to improve the quality of 20%RP textured protein, this experiment added different proportions of sodium tripolyphosphate (STPP) to improve the quality of the product, and studied the physical-chemical properties and molecular structure changes of the product to explore the possible modification mechanism. The STPP not only improved the expansion characteristics of extrudates, but also increased the brightness of the extrudates, the rehydration rate. In addition, STPP increased the specific mechanical energy during extrusion, decreased the material mass flow rate. Furthermore, STPP decreased the starch digestibility, increased the content of slow-digesting starch and resistant starch. STPP increased the degree of denaturation of extrudate proteins, the proportion of β-sheets in the secondary structure of proteins, as well as the intermolecular hydrogen bonding interactions. The gelatinization degradation degree of starch molecules also decreased with the addition of STPP. STPP also increased the protein-starch interactions and enhanced the thermal stability of the extrudate. All these indicate that STPP can improve the physical-chemical properties of extrudate.

Extrusion of Rice and Aronia melanocarpa Pomace: Physical and Functional Characteristics of Extrudates

In this study, black chokeberry (Aronia melanocarpa) juice pomace was used to enrich the extrudates from rice in order to create a functional food. A response surface methodology was applied to optimize the physical (expansion ratio, bulk density, moisture content, hardness, pellet durability index, and color) and functional (water solubility index, water absorption index) characteristics of the extrudates. A laboratory single-screw extruder was used to produce the extrudates and a full factorial experimental design was applied (N = 32) to present the effect of the amount of chokeberry pomace (10 and 20%), the feed moisture content (14 and 20%) and the working screw speed (180 min−1 and 220 min−1) of the extruder on the physical and functional characteristics. The results showed that the three factors influenced all studied characteristics. An exception with statistically insignificant effect was the amount of chokeberry pomace on the expansion ratio, pellet durability index, water adsorption index, lightness, redness, and yellowness, the feed moisture content on the water solubility, water adsorption index, redness and yellowness, and the working screw speed on the bulk density and hardness.

Effect of protease hydrolysis pretreatment on extruder response and the structural characteristics of high-moisture plant-protein extrudates

This study aimed to investigate the effect of protease hydrolysis pretreatment (PHP) on extruder response and the structural characteristics of high-moisture plant-protein extrudates. The results showed that specific mechanical energy of the extruder decreased from 147.06 kJ/kg to 116.14 kJ/kg, which reduced the energy consumption of the extruder and was beneficial for the application of hydrated wheat gluten with strong viscoelasticity during the extrusion process. Texturization degree that characterized the fibrous structure formation of high-moisture plant-protein extrudates reduced from 1.70 to 1.05. The hardness and chewiness decreased, while the springiness of the extrudates increased. Moderate PHP weakened the cross-linking strength and viscoelasticity of the extrudates, which can improve the problem of the excessively dense texture of high-moisture plant-protein extrudates. Meanwhile, PHP improved protein extractability and increased immobilized water and free water content in the extrudates.

Development of innovative tigernut-based nutritional snack by extrusion process: effects of die temperature, screw speed, and formulation on physicochemical characteristics

Tigernut (TN) is an underutilized crop with nutritional value that has remained untapped in producing extruded products. This research aims to establish the favorable extrusion conditions that produce a TN-based nutritive extruded snack with improved physicochemical characteristics. A collet extruder was used in this comparison study to examine the effects of formulation (60% TN flour and 40% brown rice [BR] vs. 60% TN flour and 40% Japonica rice [JR]). The effects of extrusion conditions, such as die temperature (90°C, 100°C, and 110°C) and screw speed (250, 300, and 350 rpm), on the physicochemical characteristics of extrudates were studied. TN-BR extrudates produced at 110°C and 350 rpm had the following improved characteristics: protein (6.09–7.33%), ash (1.40–1.59%), crude fat (7.15–9.90%), crude fiber (2.51–3.92%), reduced hardness (2.35–3.37 N), springiness (2.30–2.64), chewiness (234.71–256.72 N), bulk density (1.17–2.57 g/cm3), expansion ratio (1.65–2.24), color (L*: 68.86–74.30), water absorption index (2.69–3.45 g/g), water solubility index (13.95–21.75%), and oil absorption capacity (23.65–25.64 g/g). Extrudates produced at lower temperatures (90°C and 100°C) and screw speed (250 and 300 rpm) exhibited lesser surface consistency than the extrudates produced at 110°C and 350 rpm. The antioxidant activity and the total phenolic content (40.91–49.63 mg gallic acid equivalent/100 g) were improved significantly. Similar improvements were observed in TN-JR extrudates; however, TN-BR extrudates had better nutritional value (higher protein: 7.33%, higher ash: 1.59%, and higher antioxidant activity). The results could help with economic success, food nutrition improvement, and food security by exploiting the underutilized TN crop for sustainable extruded snacks production.

Physical characteristics of extrudates from wheat semolina enriched with cocoa bean shells

Response surface methodology was used to investigate the effect of cocoa bean shells content (5 % and 10 %), moisture content (14 % and 20 %) and temperature of the matrix (160 °C and 180 °C) on the physical characteristics of wheat semolina extrudates with cocoa bean shells. The extrusion was carried out on a single screw extruder Brabender 20 DN. A full factorial experiment 23 was used to evaluate the influence of above mentioned parameters on the water absorption index (WAI), water solubility index (WSI) and moisture content (W). The water absorption index varies between 7.13 g/g and 9.91 g/g, water solubility index between 9.34 % and 22.48 % and moisture content between 7.75 % and 11.31 % respectively. The data show that the increase of the moisture content from 14 % to 20 % increases the water absorption index and decreases the water solubility index while the increase of cocoa bean shells content from 5 % to 10 % results in lower water absorption index and higher water solubility index. Temperature of the matrix has no influence on the moisture content and water absorption index. The water solubility index decreases when the temperature of the matrix increases.

Improving transmission loss performance of aluminum extrusion in railway vehicles using lightweight material

This study developed a method for improving the transmission loss performance of aluminum extrusion by reinforcing the inner space of the extruded material with a lightweight material, such as acrylic plastic. First, the dynamic characteristics of the aluminum extrusion were analyzed, and the characteristics of noise transmission were evaluated through an acoustic mode analysis of the air layer for the inner space of the extruded material. Furthermore, to improve the transmission loss performance of the aluminum extrusion, methods were developed for increasing the vibration stiffness and altering the acoustic mode of the inner space. Additionally, a simulation analysis of the vibration mode and a response analysis based on the excitation of sound were performed to validate the proposed model; the effectiveness of the model for noise and vibration reduction was compared with that of the existing model. This analysis was conducted using models wherein the acrylic plastic was partially and totally inserted into the interior space of aluminum extrusion. The results indicated that the noise performance of the short reinforcement model with the partially inserted acrylic plastic was improved by 3 dB and that of the long reinforcement model with the totally inserted acrylic plastic was degraded by &gt; 4 dB compared with the existing aluminum panel.

Sorption and mass exchange characteristics of extrudates enriched with cocoa bean shells

The aim of the experimental work was to determine the sorption isotherms of wheat extrudates enriched with cocoa bean shells at different temperatures (10 °C, 25 °C, 40 °C) and water activities (0.11 to 0.85) using the static gravimetric method. Five three parameter models (Chung-Pfost, Halsey, Oswin, Henderson, GAB) were applied to survey the experimental data. It was established that the isotherms demonstrate Types II, according to the Brunauer’s classification and the Oswin and Chung-Pfost models were suitable for describing the relationship between the equilibrium moisture content and the water activity. The monolayer moisture content was established using the Brunauer-Emmett-Teller equation and ranged within 5.08 % d.b. and 7.80 % d.b., respectively. The increase of temperature decreases the sorption characheristics of the examined extrudates. The specific surface area of sorption for wheat extrudates enriched with cocoa bean shells varies between 181.59 (m2/g) and 278.82 (m2/g). It was found that the increase of temperature of the matrix in the range of 10 °C to 40 °C decreases the values of monolayer moisture content and the specific surface area of sorption.

Physical characteristics of extrudate with treatment composition ratio of mixed corn grit-soybean flour and extruder barrel temperature

Yellow corn is one of the key component in the production of popular RTE snacks. However, corn’s nutritional quality is relatively low, necessitating the incorporation of additional ingredients such as soybean to enrich the protein content. This study primarily aims to explore the influence of soybean flour composition and temperature of barrel on the physical characteristics of extrudates to produce nutrition-rich snacks. The materials utilized in the experiment consisted of corn grit (mesh 24) and soybean flour (mesh 80). Extrudates were produced using SYSLG twin-screw extruder machine with a 10-15 kg/h production capacity. The study’s experimental design employed two factors: the composition factor of soybean flour (at 10%, 20%, and 30%) and the final temperature of the barrel (at 120°C, 130°C, and 140°C). The physical attributes of the extrudates were assessed based on the parameters such as expansion ratio, extrudate texture (hardness), moisture content, WAI, and WSI. The study findings revealed that increased soybean flour composition reduced the expansion properties and a more rigid material texture. On top of that, all extrudates exhibited moisture content of less than 4% (wb). The water absorption index decreased with higher soybean flour composition and barrel temperature, whereas the water solubility index showed an increasing trend. Among the tested conditions, the treatment with temperature of the barrel of 140°C and a soybean ratio of 20% demonstrated the best quality results.

Physical characteristics of extrudate from mixed corn grit – red bean flour with treatment of moisture content and extruder barrel temperature

Extruded snacks, typically derived from low-protein corn, can significantly benefit from the incorporation of red beans to boost their protein content and enhance overall nutritional value. In this study, the influence of feed moisture content and extruder barrel temperature on various physical attributes of the extruded products, including moisture content, particle density, bulk density, expansion ratio, and hardness, were examined. The snacks were produced using a SYSLG-IV twin-screw extruder with a throughput capacity of 10-15 kg/h. The ingredient composition remained consistent, consisting of a 20% red bean flour and 80% corn grit blend. Three moisture content levels (14%-18%) and three different extruder barrel temperature settings (120°C-140°C) were used as variables. The results demonstrated that both variables significantly impacted the physical properties of the extruded snacks. Specifically, an increase in feed moisture content or a decrease in barrel temperature led to higher moisture content (1.01%-1.82%), greater particle density (0.17 g/cm3-0.39 g/cm3), increased bulk density (0.12 g/cm3-0.32 g/cm3), greater hardness (8.34 N-32.18 N), and reduced expansion ratio (2.17-3.0).

Evaluation of the Physicochemical, Nutritional, Textural, and Sensory Characteristics of Extrudates From Sorghum and Orange‐Fleshed Sweet Potato Flour Blends

This study is aimed at producing extrudates using sorghum and orange‐fleshed sweet potato (OFSP) flour in varying ratios (90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, and 20:80), with extrudates made from 100% sorghum serving as the control. The puffed snacks’ physicochemical, nutritional, textural, and sensory qualities were assessed, and the obtained data were analyzed through ANOVA. Our findings revealed notable variations in the physicochemical properties of the puffed snacks, showing a decrease in moisture, fat, protein, and crude fibre content as the percentage of OFSP flour increased. Furthermore, increased substitution of sorghum flour with OFSP in the extrudates led to a corresponding rise in vitamin A, B1, and C levels from 0.24, 0.15 and 0.21 mg/100 g in the control to 1.30, 0.19, and 1.82 mg/100 g in the extrudates made from 20% sorghum. More so, samples with increased OFSP content were preferred regarding springiness, chewiness, gumminess, and cohesiveness, whereas those with elevated percentages of sorghum received higher likeness for adhesiveness and stringiness. Extruded samples containing 80% and 90% sorghum levels received the highest overall acceptance ratings of 7.15 and 7.18, respectively. The research results are essential for the food industry to produce nutritious extrudates with appealing sensory characteristics and textures.

Outcomes of surgically and conservatively managed thoracolumbar and lumbosacral intervertebral disc herniations in cats.

Limited information is available regarding intervertebral disc herniation (IVDH) and its treatment in cats. Describe outcomes after surgical or conservative treatment of cats with thoracolumbar and lumbosacral IVDH. Ninety-two cats from 2 referral populations (2012-2022) with compressive IVDH between the T3 and S1 vertebrae. Retrospective cohort study evaluating outcomes of surgical (49 cats) and conservative (36 cats) management of IVDH; 7 cats were euthanized at diagnosis. Outcome was assessed using hospital and referring veterinarian records and client questionnaires. Successful outcome was defined as regained or improved ambulation, urinary and fecal continence, and no requirement for analgesic medication. Incidence of IVDH during the study period was 0.44% (92/20849). Surgical treatment resulted in 62% (6 weeks) and 74% success (6 months). Conservative treatment resulted in 54% (6 weeks) and 65% success (6 months). Neurological grade at presentation was higher in cats treated surgically (median, 2; range, 1-5) than in those treated conservatively (median, 2; range, 0-4; P = .001). Regardless of treatment type, cats suffering trauma were more likely to have a successful outcome 6 weeks after treatment compared with those without history of trauma (odds ratio, 5.3; 95% confidence interval, 1.05-26.78; P = .04). Neurological deficits remained in the majority of cats for both treatment types (92%, conservative; 86%, surgical at 6 weeks). Acute-on-chronic IVDH with characteristics of both extrusion and protrusion were identified in 10% of cats. Conservative treatment could be as effective as surgical decompression in cats with thoracolumbar or lumbosacral IVDH.

Unlocking the potential of pasting properties to predict extrudate characteristics of corn grits blends with high amylose corn starch, potato starch, or rice flour.

The development of new production lines of extruded ready-to-eat (RTE) snacks often results in high losses of edible food due to the trial-and-error approach in industry. Being able to predict extrudate characteristics of new formulations before having to run trials on industrial scale would be beneficial for reducing waste and having a more efficient development process. With this study, the correlation between pasting properties of seven blends of flours/starches and extrudate characteristics was investigated (100% corn grits, 25% and 50% replacement of corn grits with high amylose starch, potato starch, and rice flour). The predictive power of pasting characteristics on extrudate's moisture content, water absorption and solubility index, sectional expansion index (SEI) and hardness was studied. Results indicated the potential of predicting SEI, water solubility index (WSI), and water absorption index (WAI) of RTE-snacks. WSI and WAI were, respectively, negatively correlated with peak temperature (R2 =0.897), and positively with peak temperature and positively with trough viscosity (R2 =0.855). One can conclude that the rheometer can be a useful tool to gain insight into the characteristics of the extrudate, although further research with enlargement of the dataset is necessary to make the rheometer effectively deployable for potentially other extrudate characteristics.

Impact of extrusion processing on bioactive compound enriched plant-based extrudates: A comprehensive study and optimization using RSM and ANN-GA

The present study aimed to investigate the influence of extrusion process parameters, specifically screw speed (300 to 500 rpm) and temperature (130 to 150 °C) on the stability of phytosterols and the physical, functional, and structural characteristics of extrudates made from composite blends containing pea protein isolate (PPI). Response Surface Methodology (RSM) and Artificial Neural Network-Genetic Algorithm (ANN-GA) were employed to optimize the process parameters.Extrudates produced at lower temperatures exhibited higher phytosterol retention compared to those produced at higher temperatures. X-ray diffraction analysis showed that incorporating PPI significantly increased crystallinity from 22% to 33%. Fourier Transform Infrared analysis revealed a reduction in the Amide II stretching of the secondary structure in pea protein isolate following extrusion. Scanning electron microscopy images demonstrated that the addition of PPI and functional oil altered the structure of the extrudates.Statistical comparison of the process parameters using higher R2 values, lower root mean square as well as mean absolute percentage error indicated that the ANN model outperformed the RSM model in predicting all responses. Overall, incorporating PPI and phytosterols into corn-based extrudates improved their nutritional quality. These findings contribute to meeting the demand for fortified foods.

Effect of wheat dextrin on corn flour extrusion characteristics

Wheat dextrin is a modified wheat starch, classified as water-soluble. This study investigated the effect of wheat dextrin as an ingredient in corn flour blends on extrusion characteristics. Blends were prepared at 0, 10 and 20 % fibre content. DOE was used to design experiments and investigate the effects of variables selected to be studied. Feed moisture content was set at 18–25 %, temperature at 110–150 °C and specific feeding load at 0.100–0.150kg/rev. Moisture content, water absorption and solubility indices, color, sectional expansion index, density, hardness, crispiness (work (Wc) and number of spatial ruptures (Nsr)) and specific mechanical energy were evaluated. A regression model was established using response surface methodology, and processing conditions for optimal quality were generated (e.g., WSI: 96.9 %, SME: 96.9 %, final MC: 93.9 %). Wheat dextrin solubility characteristics for moisture content, WAI and WSI were inconclusive, showing a high tendency to insoluble behavior. For expansion, lightness and SME characteristics depended on processing conditions, especially temperature. Crispness was highest at low MC (18.87 %) x high fiber content (20 %) (e.g., Nsr: 1.2–1.5/mm), whereas values were the lowest at high MC (25.70 %) x low fiber content (0 %) (e.g., Nsr: 0.5–0.7/mm). Optimal conditions were set at 12 % fiber content, 19 % feed moisture content, 130 °C and a specific feeding load of 0.146 kg/rev. This study showed that it is impossible to classify wheat dextrin as acting strictly according to soluble fiber characteristics based on extrudate characteristics.