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Gluten-free baked products often present quality defects, low nutritional value and low sensorial quality. The supplementation of non-wheat flour and dough with healthy dietary fibres (DFs) and prebiotic is a usual practice for increasing the nutritional value of gluten-free products while improving their texture, shelf-life and mouthfeel. However, the effectiveness of DFs to mimic the properties of gluten to overcome problems of gluten-free systems or promote health benefits depends not only on extraction process but also on their source, structural and chemical composition. Pectin and their oligosaccharides are valuable compounds providing the known associated health benefits. In this paper, we examined two methods for extracting DFs from soy hulls, which are waste streams generated during the production of soy proteins. Specifically, these methods include acid extraction using a 0.5 M HCl solution for 30 min and ultrasonic extraction performed in cycles under the following conditions: 22-25 kHz, duty cycle 0.67, power 490 W (90%). Extracted DFs was characterized regarding its galacturonic acid (GalA) content, degree of methoxylation (DM), degree of acetylation (DA) and functional properties like water (WHC) and oil (OHC) holding capacities, as well as solubility. Significantly higher yield of DFs was achieved with acid extraction, and the functional properties of the extracted fibers were satisfactory. Content of GalA amounted 40% (m/m), DM was determined to be 30% and DA 0.9%. Average MW determined by HPSEC was 1815 kDa, WHC was amounted to 12 g/g while OHC was 2.44 g/g. Solubility was determined to be 50%. The obtained fibers were incorporated into rice cookies: a control batch with rice flour and two batches with 10% (10CDF) and 20% (20CDF) fiber substitution. The addition of pectic fibers resulted in darker, smaller cookies with decreased hardness (29% for 10CDF and 14% for 20CDF). The cookies also exhibited better nutritional, textural and sensory properties

RuBisCO (ribulose-1,5-diphosphate carboxylase/oxygenase), an enzyme crucial for plant photosynthesis, is the most widespread protein in the living world. It is predominantly found in the leaves of plants, which mostly remain unused after harvesting. Despite current efforts, the RuBisCO protein isolated from leaves has not yet found significant application as a supplement in human nutrition, due to the complexity and cost-effectiveness of the production process and the low yield. Two ultrafiltration methods were applied for isolation of RuBisCO protein. Initially, cross-flow ultrafiltration was used, employing a membrane module with a membrane’s pore size 10 kDa. The second method involved dead-end ultrafiltration with a feed flow under a nitrogen stream at a defined pressure, using a membrane with a pore size of 100 kDa. The obtained ultrafiltration fractions were used for the analysis of soluble protein content and protein yield, reducing sugars and polyphenols. The efficiency of the ultrafiltration process and the protein purity were determined by SDS-PAGE electrophoresis. Also, the obtained protein powders were analyzed for the total and free sulfhydryl group contents and surface hydrophobicity. These protein powders were characterized in terms of their technological and functional properties, including solubility, emulsifying properties, and water/oil binding capacities. The results were then compared with those of protein powder obtained from pumpkin leaves using the most common method, isoelectric precipitation. The different techniques for isolating RuBisCO protein showed certain variations in protein yield as well as in its structural and technological-functional properties. Different isoelectric point values were shown for all three protein powders, including variations in the content of free and total sulfhydryl groups. Furthermore, surface hydrophobicity and oil binding capacity showed lower values for the RuBisCO protein obtained by ultrafiltration metho

Gluten-free baked products often present quality defects, low nutritional value and low sensorial quality. The supplementation of non-wheat flour and dough with healthy dietary fibres (DFs) and prebiotic is a usual practice for increasing the nutritional value of gluten-free products while improving their texture, shelf-life and mouthfeel. However, the effectiveness of DFs to mimic the properties of gluten to overcome problems of gluten-free systems or promote health benefits depends not only on extraction process but also on their source, structural and chemical composition. Pectin and their oligosaccharides are valuable compounds providing the known associated health benefits. In this paper, we examined two methods for extracting DFs from soy hulls, which are waste streams generated during the production of soy proteins. Specifically, these methods include acid extraction using a 0.5 M HCl solution for 30 min and ultrasonic extraction performed in cycles under the following conditions: 22-25 kHz, duty cycle 0.67, power 490 W (90%). Extracted DFs was characterized regarding its galacturonic acid (GalA) content, degree of methoxylation (DM), degree of acetylation (DA) and functional properties like water (WHC) and oil (OHC) holding capacities, as well as solubility. Significantly higher yield of DFs was achieved with acid extraction, and the functional properties of the extracted fibers were satisfactory. Content of GalA amounted 40% (m/m), DM was determined to be 30% and DA 0.9%. Average MW determined by HPSEC was 1815 kDa, WHC was amounted to 12 g/g while OHC was 2.44 g/g. Solubility was determined to be 50%. The obtained fibers were incorporated into rice cookies: a control batch with rice flour and two batches with 10% (10CDF) and 20% (20CDF) fiber substitution. The addition of pectic fibers resulted in darker, smaller cookies with decreased hardness (29% for 10CDF and 14% for 20CDF). The cookies also exhibited better nutritional, textural and sensory properties

RuBisCO (ribulose-1,5-diphosphate carboxylase/oxygenase), an enzyme crucial for plant photosynthesis, is the most widespread protein in the living world. It is predominantly found in the leaves of plants, which mostly remain unused after harvesting. Despite current efforts, the RuBisCO protein isolated from leaves has not yet found significant application as a supplement in human nutrition, due to the complexity and cost-effectiveness of the production process and the low yield. Two ultrafiltration methods were applied for isolation of RuBisCO protein. Initially, cross-flow ultrafiltration was used, employing a membrane module with a membrane’s pore size 10 kDa. The second method involved dead-end ultrafiltration with a feed flow under a nitrogen stream at a defined pressure, using a membrane with a pore size of 100 kDa. The obtained ultrafiltration fractions were used for the analysis of soluble protein content and protein yield, reducing sugars and polyphenols. The efficiency of the ultrafiltration process and the protein purity were determined by SDS-PAGE electrophoresis. Also, the obtained protein powders were analyzed for the total and free sulfhydryl group contents and surface hydrophobicity. These protein powders were characterized in terms of their technological and functional properties, including solubility, emulsifying properties, and water/oil binding capacities. The results were then compared with those of protein powder obtained from pumpkin leaves using the most common method, isoelectric precipitation. The different techniques for isolating RuBisCO protein showed certain variations in protein yield as well as in its structural and technological-functional properties. Different isoelectric point values were shown for all three protein powders, including variations in the content of free and total sulfhydryl groups. Furthermore, surface hydrophobicity and oil binding capacity showed lower values for the RuBisCO protein obtained by ultrafiltration metho

The potential of food biodiversity and its production streams to generate additional features for isolating high-value products has been underutilized. Even so, the recovery of valuable nutritional compounds like proteins from waste streams and by-products has been identified as a key strategy for enhancing production sustainability in order to open up new market potential. In accordance with those facts, the primary aim of this research was to utilize a relatively novel extraction technique, high-intensity ultrasound, in order to achieve a reduction in time, energy, and extraction solvent consumption while at the same time improving the extraction yield and nutritional value of extracted leaf proteins. For this purpose, an ultrasound probe system with a low frequency (20±0.2 kHz) was utilized to extract the white proteins from the pumpkin leaf biomass, and the effects of different sonication amplitudes (20, 30, 40, 50, 60 and 70%) and duration periods (0, 1, 3, 5, 7.5, 10, 12.5, 15, 17.5, and 20 min) on the yield, solubility and emulsifying qualities, antioxidant properties, and structural characteristics of proteins were studied. In the functional properties evaluated, leaf proteins isolated using ultrasound outperformed those extracted using the conventional extraction method, maceration. High-intensity ultrasound resulted in a slight but gradual decline in solubility with an increase in amplitude, but a significant increase in solubility in an acidic environment was observed with the decrease of cavitation periods. Ultrasound-extracted proteins exhibit nearly 12, 1.5, and 3-fold greater solubility compared to the maceration-extracted sample at pH 3, 4, and 5, respectively. The emulsifying activity diminishes with increasing sonication amplitude and duration but increases in emulsifying stability as sonication periods are extended. The ultrasound extraction provided pumpkin proteins with high radical scavenging activities (i.e., good electron donors) and chelatin

The aim of this study was to develop a stable hydrogel carrier system for thyme essential oil (TEO) that could protect its sensitive polyphenol compounds. The impact of wall material (soy protein and alginate) on encapsulation efficiency and thymol release in simulated gastrointestinal conditions, was investigated. The release of thymol was ~ 80 % and 20 % in simulated gastric and pancreatic solutions, respectively. Thyme essential oil plays an important role as an antimicrobial and antioxidant agent. Results indicated that encapsulated TEO inside the hydrogel matrix exhibited antioxidant activity demonstrated by CUPRAC and ABTS analysis, even after thermal treatment of the beads, indicating the metal chelate effect as dominant. In vitro antimicrobial activity of encapsulated TEO has been studied against several pathogenic microorganisms such as Escherichia coli, Staphylococcus aureus, Bacillus cereus and Candida albicans. Beads coded as Ca-A1.5/SP1.5 showed anti-Candida albicans activity, while modified bead formulations Ca-A1.5/SP1.5* and Ca-A1.5/SP0.25** showed bactericidal activity against Escherichia coli and Staphylococcus aureus.

Komercijalna primena hidrolizata proteina soje još uvek je ograničena zbog male bioraspoloživosti peptida, gorkog ukusa, higroskopnosti i reaktivnosti u prehrambenim proizvodima. Cilj ovog istraživanja jeste inkapsulacija hidrolizata soje u lipozome kako bi se prevazišli navedeni nedostaci, uz očuvanje bioloških aktivnosti. Hidrolizat soje inkapsuliran je u lipozome metodom tankog filma koristeći lipidnu smešu sa fosfatidilholinom. Dobijene multilamelarne vezikule tretirane su ultrazvučnim talasima visokog intenziteta frekvence 20 - 40 kHz. Najmanji i najuniformniji lipozomi, unimodalne raspodele i srednje veličine prečnika 310 nm, sa najvećom efikasnošću inkapsulacije hidrolizata od ~19 %, dobijeni su primenom ultrazvučne sonde (20 kHz). Utvrđeno je da je inkorporiranje hidrolizata ostvareno unutar lipozomne membrane uzrokovalo povećanje veličine lipozoma, npr. sa 297 na 310 nm. Sve formulacije lipozoma okarakterisane su negativnom vrednošću zeta potencijala, pri čemu je povećanje negativnog naelektrisanja ispod 30 mV u slučaju multilamelarnih vezikula ukazalo na veću stabilnost lipozoma sa inkapsuliranim hidrolizatom. Merenjem sposobnosti inhibicije ABTS•+ radikalskog katjona i sposobnosti heliranja Fe2+ jona potvrđeno je zadržavanje antioksidativne aktivnosti hidrolizata soje nakon inkapsulacije. Pripremljene lipozomne formulacije obezbeđuju produženo oslabađanje hidrolizata (2,25 puta manje) u odnosu na neinkapsuliran hidrolizat pokazujući potencijal primene u oblasti prehrambene tehnologije, za razvoj funkcionalne hrane, povećanje hranljive vrednosti i roka trajanja prehrambenih proizvoda., Soy proteins known for their high nutritional value and pronounced techno-functional properties, can be hydrolyzed by using proteolytic enzymes and thus converted into hydrolysates rich in di-, tri- and oligopeptides. The resulting peptides are carriers of valuable biological activities, which make the soy hydrolysates very important in functional food applications as techno-functional and bioactive ingredients. However, commercial incorporation and application of soy protein hydrolysates can be hinderedby their low bioavailability and instability, bitter taste, hygroscopicity and possibility to interact with the food matrix. The aim of this research is encapsulation of the soy protein hydrolysate in liposomes in order to overcome the stated shortcomings, while preserving the biological activities that protein hydrolysates exhibit. The soy hydrolysate was prepared by a two-step enzymatic hydrolysis of a soy protein concentrate using commercial food-grade proteases, endoprotea se from Bacillus amyloliquefaciens (Neutrase (R)) and egzoand endoprotease from Aspergillus oryzae (Flavourzyme (R)) and encapsulated within liposomes. The liposomes were produced by a thin film method using a commercial lipid mixture (Phospolipon (R) 90G) containing mainly phosphatidylcholine. Next, the obtained multilamellar vesicles (MLV) with the soy protein hydrolysate were treated by high-intensity ultrasound waves generated by using (1) an ultrasonic probe at a frequency of 20 kHz and (2) an ultrasonic bath with a frequency 40 kHz. The smallest (310 nm) and uniform (unimodal size distribution) liposomes with the highest efficiency of peptide encapsulation (19 %) were obtained by the probe sonication. The presented results showed that incorporation of the soy protein hydrolysates was achieved within the liposome membrane and caused an increase in the liposome size in all tested formulations, namely: from 297 to 310 nm by using the ultrasonic probe, from 722 to 850 nm by using the ultrason

Komercijalna primena hidrolizata proteina soje još uvek je ograničena zbog male bioraspoloživosti peptida, gorkog ukusa, higroskopnosti i reaktivnosti u prehrambenim proizvodima. Cilj ovog istraživanja jeste inkapsulacija hidrolizata soje u lipozome kako bi se prevazišli navedeni nedostaci, uz očuvanje bioloških aktivnosti. Hidrolizat soje inkapsuliran je u lipozome metodom tankog filma koristeći lipidnu smešu sa fosfatidilholinom. Dobijene multilamelarne vezikule tretirane su ultrazvučnim talasima visokog intenziteta frekvence 20 - 40 kHz. Najmanji i najuniformniji lipozomi, unimodalne raspodele i srednje veličine prečnika 310 nm, sa najvećom efikasnošću inkapsulacije hidrolizata od ~19 %, dobijeni su primenom ultrazvučne sonde (20 kHz). Utvrđeno je da je inkorporiranje hidrolizata ostvareno unutar lipozomne membrane uzrokovalo povećanje veličine lipozoma, npr. sa 297 na 310 nm. Sve formulacije lipozoma okarakterisane su negativnom vrednošću zeta potencijala, pri čemu je povećanje negativnog naelektrisanja ispod 30 mV u slučaju multilamelarnih vezikula ukazalo na veću stabilnost lipozoma sa inkapsuliranim hidrolizatom. Merenjem sposobnosti inhibicije ABTS•+ radikalskog katjona i sposobnosti heliranja Fe2+ jona potvrđeno je zadržavanje antioksidativne aktivnosti hidrolizata soje nakon inkapsulacije. Pripremljene lipozomne formulacije obezbeđuju produženo oslabađanje hidrolizata (2,25 puta manje) u odnosu na neinkapsuliran hidrolizat pokazujući potencijal primene u oblasti prehrambene tehnologije, za razvoj funkcionalne hrane, povećanje hranljive vrednosti i roka trajanja prehrambenih proizvoda., Soy proteins known for their high nutritional value and pronounced techno-functional properties, can be hydrolyzed by using proteolytic enzymes and thus converted into hydrolysates rich in di-, tri- and oligopeptides. The resulting peptides are carriers of valuable biological activities, which make the soy hydrolysates very important in functional food applications as techno-functional and bioactive ingredients. However, commercial incorporation and application of soy protein hydrolysates can be hinderedby their low bioavailability and instability, bitter taste, hygroscopicity and possibility to interact with the food matrix. The aim of this research is encapsulation of the soy protein hydrolysate in liposomes in order to overcome the stated shortcomings, while preserving the biological activities that protein hydrolysates exhibit. The soy hydrolysate was prepared by a two-step enzymatic hydrolysis of a soy protein concentrate using commercial food-grade proteases, endoprotea se from Bacillus amyloliquefaciens (Neutrase (R)) and egzoand endoprotease from Aspergillus oryzae (Flavourzyme (R)) and encapsulated within liposomes. The liposomes were produced by a thin film method using a commercial lipid mixture (Phospolipon (R) 90G) containing mainly phosphatidylcholine. Next, the obtained multilamellar vesicles (MLV) with the soy protein hydrolysate were treated by high-intensity ultrasound waves generated by using (1) an ultrasonic probe at a frequency of 20 kHz and (2) an ultrasonic bath with a frequency 40 kHz. The smallest (310 nm) and uniform (unimodal size distribution) liposomes with the highest efficiency of peptide encapsulation (19 %) were obtained by the probe sonication. The presented results showed that incorporation of the soy protein hydrolysates was achieved within the liposome membrane and caused an increase in the liposome size in all tested formulations, namely: from 297 to 310 nm by using the ultrasonic probe, from 722 to 850 nm by using the ultrason

α-Glucosidase from S. cerevisiae was covalently immobilized onto Sepabeads EC-EA by the glutaraldehyde method. An analysis of the variables controlling the immobilization process is first presented and it is shown that the highest coupling of α-glucosidase occurred within 24 h. Also, a loading of 30 mg/g support proved to be effective, resulting in a rather high activity of around 45 U g-1 with a satisfactory degree of enzyme fixed. Both free and immobilized enzymes were then characterized by determining the activity profile as a function of pH, temperature and thermal stability. The obtained immobilized preparation showed the same optimum pH, but a higher optimum temperature compared with the soluble one. In addition, the immobilized enzyme treated at 45°C for 1 h still retained an activity of around 20 %, whereas the free enzyme completely lost its original activity under this condition. In conclusion, the developed immobilization procedure is quite simple, easily reproducible and provides a promising solution for the application of immobilized α-glucosidase., Малтаза из S. cerevisiae је ковалентно имобилизована на Sepabeads EC-EA након акти- вације носача раствором глутаралдехида. Испитивањем кинетике имобилизације утврђено је да се 25 % ензима имобилизује након 24 часа. Имобилизована α-глукозидаза има исти pH оптимум као и растворни ензим, док је оптимална температура за активност имобилизованог ензима увећана за 10 °C у поређењу са растворним ензимом. Када се упореде заостале активности растворне и имобилизоване форме α-глукозидазе, након инкубације од 1 h на α- 45 °C растворни ензим не показује активност док имобилизована форма задржава око 20 % почeтне активности. Имобилизована форма ензима задржава 20 % почетне активности чак и после 3 h инкубације на 45 °C.