Extruded flour as techno-functional ingredient in muffins with berry pomace

Tannat grape pomace as an ingredient for potential functional biscuits: bioactive compound identification, in vitro bioactivity, food safety, and sensory evaluation

Grape pomace, the main by-product of wine process, shows high potential for the development of functional foods, being a natural source of bioactive compounds and dietary fiber. Thus, the present study proposes the development of five potential functional biscuits. The five formulations were achieved by varying the Tannat grape pomace powder (TGP, 10-20% w/w total wet dough) and sweetener sucralose (2-4% w/w total wet dough) content through a factorial design with central points. TGP microbiological and pesticides analysis were performed as a food safety requirement. Identification of bioactive compounds by HPLC-DAD-MS, in vitro bioactivity (total phenol content, antioxidant by ABTS and ORAC-FL, antidiabetic and antiobesity by inhibition of α-glucosidase and pancreatic lipase, respectively) and sensory properties of the biscuits were evaluated. TGP microbiological and pesticides showed values within food safety criteria. Sensory profiles of TGP biscuits were obtained, showing biscuits with 20% TGP good sensory quality (7.3, scale 1-9) in a cluster of 37 out of 101 consumers. TGP addition in biscuits had a significant (p < 0.05) effect on total phenolic content (0.893-1.858 mg GAE/g biscuit) and bioactive properties when compared to controls: 11.467-50.491 and 4.342-50.912 μmol TE/g biscuit for ABTS and ORAC-FL, respectively; inhibition of α-glucosidase and pancreatic lipase, IC50 35.572-64.268 and 7.197-47.135 mg/mL, respectively. HPLC-DAD-MS results showed all the identified phenolic compounds in 20/4% biscuit (TGP/sucralose%) were degraded during baking. Malvidin-3-O-(6'-p-coumaroyl) glucoside, (+)-catechin, malvidin-3-O-glucoside, and (-)-epicatechin were the main phenolic compounds (in descendent order of content) found. The bioactive properties could be attributed to the remaining phenolic compounds in the biscuits. In conclusion, TGP biscuits seemed to be a promising functional food with potential for ameliorating oxidative stress, glucose and fatty acids levels with good sensory quality.

Sustainability on Bread: How Fiber-Rich Currant Pomace Affects Rheological and Sensory Properties of Sweet Fat-Based Spreads

Dietary fiber may contribute to increasing the nutritional value of “unhealthy food”—for instance, spreads with high fat and sugar content. The high amount of fiber and the presence of phenolic compounds, organic fruit acids, and aroma compounds make currant pomace a promising ingredient to be used in a wide range of foods. However, the particle size of this by-product is a key factor influencing texture, rheology, physical stability, and sensory properties of the final commodities. Wet planetary ball milling of seedless currant pomace suspended in oil resulted in particles <30 µm, which is required for a creamy texture. Spread stiffness and viscosity were adapted by lowering the solid fat content in a way that the fruity spreads with 16 g/100 g pomace resembled a sweet commercial nut spread. The pomace showed stabilizing effects, as oil separation was reduced and a viscosity increase during storage was prevented. Principal component analysis after sensory flash profiling of five formulations highlighted differences in fruitiness, sweetness, greasiness, and viscosity. Hence, depending on the pomace level and fat composition in the formulation, the properties of sweet spreads can be specifically designed to fulfill the respective requirements. Additionally, sweet and savory wafer fillings provide great potential to be enriched with fruit pomace.

Techno-Functional Properties of Corn Flour with Cowpea (Vigna unguilata) Powders Obtained by Extrusion

Legumes are a good source of vegetal protein that improves diets worldwide. Cowpea has been used as fortification agents in some traditional corn foods in developing countries such as Colombia. The work aimed to evaluate the physicochemical properties of extruded mixtures of corn and cowpea flours to assess the use of these mixes as vegetable protein ingredients. Corn flour was mixed with 15, 30, and 50% of cowpea flour and extruded for this proposal. After extrusion, mixtures were ground to produce a powder. Techno-functional properties of powders as water content, hygroscopicity, water absorption, fat absorption, water solubility index, swelling index, bulk density, Hausner ratio, Carr index, and porosity were evaluated in the mixtures, extrudates, and obtained powders to assess the effect of the addition of cowpea on these properties. Results showed that processing powder obtained by extrusion and drying could be used as a powder to regenerate with water as a source of protein. Moreover, storing processing samples in sections (pellet format) is convenient to avoid wetting since this format is less hygroscopic and the same mass occupies less storage volume than powders.

Thermo-mechanical processing of fibre-rich blackcurrant pomace to modify techno-functional properties

Exploring the use of seedless blackcurrant pomace, a fibre-rich by-product of juice pressing, in foods is favourable due to its nutritional profile but also for economic and sustainability aspects. Current applications are limited to products in which rapid fibre swelling, high water solubility or low sedimentation is not essential. In this study, functional properties of seedless blackcurrant pomace were modified by thermo-mechanical treatments using extrusion cooking or micronization in a planetary ball mill. A full factorial design showed that low pomace moisture (11 g/100 g) had the highest impact on swelling capacity (+ 20.6%) and water solubility index (+ 23.2%), whereas variation in extrusion temperature exhibited only minor effects. After milling for 4 h, the median particle size was reduced by 98% to 4 µm and the specific surface area increased from 0.1 to 2.5 m2/mL. Swelling capacity was highest after this time with 7.6 mL/g pomace and, although the amount of extractable sugars was reduced, water solubility increased to 7.6 g/100 g. In contrast to extruded samples, the red colour of the pomace was intensified after milling. Both treatments appear as promising to extend the applicability of fruit by-products in foods, as micronized pomace may counteract sedimentation in liquids, whereas increased swelling capacity after extrusion may have stabilizing effects on yoghurt-like systems.

The effect of Vaccinium bracteatum Thunb. leaves addition on antioxidant capacity, physicochemical properties, and in vitro digestibility of rice extrudates

Vaccinium bracteatum Thunb.leaves (VBTL) are a traditional Chinese herbal medicine with potential natural pigments and antioxidants. Its application information on extrusion is limited. In this study, to increase the usage of foods containing VBTL, rice-based extrudates with VBTL were investigated. The extrusion was performed at a wide temperature range (60-140°C) and with different VBTL supplementations (3%-10%). The extrudates with 10% VBTL showed a significant decrease in total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity upon extrusion. TPC and TFC increased with the rise of barrel temperature. The VBTL color was stable during the wide-temperature extrusion process. The bioactivities of the extrudates were positively correlated with the VBTLsupplement (R = 0.943-0.989). In addition, different addition levels of VBTL significantly changed the water absorption index (WAI), water solubility index (WSI), pasting properties, and in vitro starch digestibility of the extrudates. Moreover, extrudates with 3% VBTL showed the highest WAI and peak viscosity but the lowest in vitro starch digestibility. These results may suggest that rice extrudates with a low supplement of VBTL have an acceptable color and may be used as functional additives for high antioxidant and low glycemic response diets. PRACTICAL APPLICATION: The results showed that the Vaccinium bracteatum Thunb. leaves (VBTL) color and antioxidation were stable during the wide-temperature extrusion process. Extrusion processing can be used to enlarge the usage of VBTL and simplify its traditional processing method. Applying VBTL to the process of extrusion appears to be a suitable method of producing value-added and low glycemic response extrudates.

Characterization of Food Packaging Films with Blackcurrant Fruit Waste as a Source of Antioxidant and Color Sensing Intelligent Material

Chitosan and pectin films were enriched with blackcurrant pomace powder (10 and 20% (w/w)), as bio-based material, to minimize food production losses and to increase the functional properties of produced films aimed at food coatings and wrappers. Water vapor permeability of active films increased up to 25%, moisture content for 27% in pectin-based ones, but water solubility was not significantly modified. Mechanical properties (tensile strength, elongation at break and Young’s modulus) were mainly decreased due to the residual insoluble particles present in blackcurrant waste. FTIR analysis showed no significant changes between the film samples. The degradation temperatures, determined by DSC, were reduced by 18 °C for chitosan-based samples and of 32 °C lower for the pectin-based samples with blackcurrant powder, indicating a disturbance in polymer stability. The antioxidant activity of active films was increased up to 30-fold. Lightness and redness of dry films significantly changed depending on the polymer type. Significant color changes, especially in chitosan film formulations, were observed after exposure to different pH buffers. This effect is further explored in formulations that were used as color change indicators for intelligent biopackaging.

Agave Syrup as an Alternative to Sucrose in Muffins: Impacts on Rheological, Microstructural, Physical, and Sensorial Properties

Natural sweeteners, such as agave syrup, might be a healthy alternative to sucrose used in sweet bakery products linked to obesity. We evaluated the effect of sucrose replacement by agave syrup on rheological and microstructural properties of muffin batter and on physical and sensorial properties of the baked product. Muffins were formulated by replacing 25%, 50%, 75%, and 100% of sucrose by agave syrup (AS) and partially hydrolyzed agave syrup (PHAS), and by adding xanthan gum and doubled quantities of leavening agents. Rheological and microstructural properties of batter during baking were analyzed over the range of 25-100 °C. In the muffins, the structure, texture, color, and sensory acceptance were studied. The combination of agave syrup with xanthan gum and doubled quantities of leavening agents affected (p < 0.05) rheological and microstructural properties of the batters and textural properties of the low-sucrose muffins compared to the controls. The increase in agave syrup levels resulted in a darker crumb and crust. Sensory evaluation showed that AS-75 and PHAS-75 were the best alternatives to the control samples. Our results suggest a plausible substitution of up to 75% of sucrose by agave syrup in preparation of muffins, with physical and sensorial characteristics similar to those of their sucrose-containing counterparts.

Optimizing High Pressure Processing Parameters to Produce Milkshakes Using Chokeberry Pomace

High hydrostatic pressure is a non-thermal treatment of great interest because of its importance for producing food with additional or enhanced benefits above their nutritional value. In the present study, the effect of high hydrostatic pressure processing parameters (200–500 MPa; 1–10 min) is investigated through response surface methodology (RSM) to optimize the treatment conditions, maximizing the phenol content and antioxidant capacity while minimizing microbiological survival, in milkshakes prepared with chokeberry pomace (2.5–10%). The measurement of fluorescence intensity of the samples was used as an indicator of total phenolic content and antioxidant capacity. The results showed that the intensity of the treatments had different effects on the milkshakes. The RSM described that the greatest retention of phenolic compounds and antioxidant capacity with minimum microbiological survival were found at 500 MPa for 10 min and 10% (w/v) chokeberry pomace. Therefore, this study offers the opportunity to develop microbiologically safe novel dairy products of high nutritional quality.