Search

Brewers spent grain (BSG) is a valuable source of arabinoxylans with potential beneficial effects on glucose values. This pilot randomised crossover double-blind trial compared the effects of panettone, a sweet baked-product, enriched with BSG-fibre (p-rich) to unenriched panettone (p-standard) on glucose and insulin blood values and appetite scores. Ten healthy volunteers consumed each food in a random order. Blood variables and appetite scores were assessed at fasting and at different intervals after each food consumption. Glucose values were significantly higher after p-standard intake at 90-min (89.9 ± 16.1 vs 74.6 ± 19.4 mg/dL) and 120-min (81.1 ± 9.85 vs 72.1 ± 14.0 mg/dL). The areas-under-the-curve (AUCs) were lower for both glucose (p =.043) and insulin values (p =.036) with p-rich. At 240-min, satiety was higher (p =.006), and desire-to-eat lower (p =.008) with p-rich; desire-to-eat AUC was lower with p-rich too (p =.029). The integration of a small amount of BSG-derived fibre into a sweet food led to improved glycaemic control and appetite regulation. [ABSTRACT FROM AUTHOR]

Beer is one of the most popular drinks in the world. In the process of beer brewing, the main solid by-products are brewers' spent grains. Those malt residues are produced in large quantities. This work focused on the utilization of BSG for the production of activated carbon. The raw material was obtained from the production of standard Pilsner beer. Technical and thermogravimetric analyzes were performed on BSG. The material was then subjected to low temperature carbonization to obtain semicoke, which was processed into activated carbon. During the experiments, two physical activation techniques and one chemical were tested: with CO2, with H2O, and solid NaOH. All of obtained materials were also examined by using FTIR technique. The results showed that steam activated carbon had bigger SBET (636 m2/g) than carbon dioxide activated (551 m2/g). The best results were obtained by using chemical activation by NaOH (3286 m2/g). Activated carbons obtained from BSG may be a feasible and cheap sorbent in water treatment plants, especially those located close to the brewery. [ABSTRACT FROM AUTHOR]

A thermal diluted acid pretreatment using brewers spent grain (BSG) was optimised to improve enzymatic hydrolysis while minimising energy and chemical inputs. First, the use of hydrochloric or sulfuric acid for pretreatment was compared, using hydrochloric acid for the next steps. Three different dilute acid thermal pretreatment combinations were optimised in terms of acid concentration, temperature and time using a response surface methodology. Optimization was based on i) highest remaining protein content in the solid fraction (C1: 0.49% HCl; 87.7°C; 92 min), ii) highest liquid recovery (C2: 0.80% HCl; 121.0°C; 142 min), iii) lowest acid concentration applied to achieve largest protein and lowest remaining solid levels (C3: 0.10% HCl; 104.0°C; 70 min); and iv) a final condition based on the lowest water retention capacity when using HCl (C4: 0.20% HCl; 121.0°C; 20 min). The efficiency of enzymatic hydrolysis was evaluated, in the absence and presence of a large concentration of reducing carbohydrates, by centrifuging the slurry after acid pretreatment, recovering the solid fraction and resuspending it in fresh water. In C2, the enzyme (Depol 40L) was added directly to the entire slurry after pretreatment. For C1, C3, and C4 direct addition of enzyme to the whole slurry resulted in a higher release of carbohydrates during hydrolysis. Only in the case of C2 did the use of the resuspended solid result in a higher carbohydrate release. The overall carbohydrate recovery efficiency in the liquid fractions for C1, C2, C3 and C4 corresponded to 399.1 (±26.1), 535.8 (±28.7), 257.0 (±11.5), and 446.3 (±81.1) mg carbohydrate per Gram of BSG (dry weight), respectively. C1 and C4 were considered the optimal pretreatments as these combined a low acid concentration and energy input prior to enzymatic hydrolysis.

Thermal processing not only disrupts cell membranes and cell walls, but also cleaves covalent bonds releasing low molecular phenolic. This study examined the impact of various heat treatments (100, 140, and 160°C) on the composition of phenolic acids and antioxidant activities in extracts obtained from defatted brewers spent grain (BSG) meal. Heating BSG at 160°C resulted in a 2-fold increase in total phenolic content [TPC, 172.98 ± 7.3 mg Gallic acid equivalent (GAE)/100 g defatted meal] and total flavonoid content [TFC, 16.15 ± 2.22 catechin equivalents (CE)/100 g defatted meal] compared to the untreated BSG extracts. The antioxidant activities of treated BSG extracts, determined by radical scavenging and ferric reducing antioxidant power (FRAP) were significantly (p < 0.5) higher than the corresponding untreated BSG extracts. Eleven phenolic acids were identified and quantified in BSG extracts by Ultra Performance Liquid Chromatography with Photodiode Array (UPLC-PDA). The amounts varied significantly (p < 0.05) depending on the degree of toasting BSG was subjected to. Chlorogenic acid, an ester of caffeic and quinic acid was the predominant phenolic acid present in all fractions. Significant (p < 0.05) increases in TPC, TFC, individual phenolic acids and antioxidant activity were observed in BSG extracts exposed to increasing oven temperatures. These results confirm the ability of heat processing to release bioactive phenolic from their bound forms thereby enhancing the phenolic acids and the digestibility of BSG meal in the intestinal tract.

Waste lignocellulose materials, such as brewers' spent grain, can be considered very promising sources of fillers for the manufacturing of natural fiber composites. Nevertheless, due to the chemical structure differences between polymer matrices and brewers' spent grain, filler treatment should be included. The presented work aimed to investigate the impact of fillers' reactive extrusion on the chemical structure and the poly(ŝ-caprolactone)/brewers' spent grain composites' mechanical performance. The chemical structure was analyzed by Fourier-transform infrared spectroscopy, while the mechanical performance of composites was assessed by static tensile tests and dynamic mechanical analysis. Depending on the filler pretreatment, composites with different mechanical properties were obtained. Nevertheless, the increase in pretreatment temperature resulted in the increased interface surface area of filler, which enhanced composites' toughness. As a result, composites were able to withstand a higher amount of stress before failure. The mechanical tests also indicated a drop in the adhesion factor, pointing to enhanced interfacial interactions for higher pretreatment temperatures. The presented work showed that reactive extrusion could be considered an auspicious method for lignocellulose filler modification, which could be tailored to obtain composites with desired properties. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of ensiled brewers spent grain (BSG) when used as replacement to cotton seed cake in the concentrate diet of lactating crossbred dairy cows. Eight early lactating F1 Boran X Friesian cows were used in a short term feeding trial to identify optimum level of ensiled BSG substitution of cotton seed cake (0, 33, 66, and 100%) in iso-nitrogenous diets. A 4 × 4 double Latin square design was used to analyze the data set generated from the feeding and digestibility trials. The results showed that as the level of ensiled BSG replacement to cotton seed cake increased, daily intakes on the natural pasture hay: 8.1 (T1) vs 7.6 (T2), 6.0 (T3), and 5.1 (T4); total feed dry matter: 14.6 (T1) vs 14.0 (T2), 12.9 (T3), and 12.2 (T4); crude protein (CP): 2.0 (T1) vs 1.9 (T2), 1.8 (T3), and 1.7 (T4); neutral detergent fiber (NDF): 8.4 (T1) vs 8.2 (T2), 7.4 (T3), and 6.8 (T4); and acid detergent fiber (ADF): 4.8 (T1) vs 4.5 (T2), 3.8 (T3), and 3.3 (T4) decreased (P < 0.05). However, estimated metabolizable energy (EME) intakes (129 vs 126) and body weight of the animals (465 vs 467) on the control diet and dietary T2 (33% BSG replacement for cottonseed cake) were comparable (P > 0.05). Thereafter, differences in daily EME intakes and body weight changes decreased with an increase in the level of ensiled BSG in the concentrate diet (P < 0.05) compared with both the control and animals on T2. Ensiled BSG, on the other hand, substantially improved (P < 0.05) total ration's apparent digestibility of dry matter (DM): 629 (T1) vs 659 (T3), 686 (T4); CP: 676(T1) vs 690(T3), 738(T4); NDF: 524 (T1) vs 544 (T3), 581 (T4); and ADF: 341 (T1) vs 350 (T2), 392 (T3), 440(T4) and daily milk yield: 14.5 (T1) vs 15.4 (T4) and milk production efficiency: 0.98 (T1) vs 1.11 (T3) and 1.26 (T4). So, ensiled BSG can be recommended to fully replace cotton seed cake from the concentrate diet of lactating dairy cows under local conditions. Additional research is needed to minimize and/or avoid body weight loss, milk fat, and total solids. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of enzymatic hydrolysis on malt bagasse for fermentative sugar extraction in thermostatic and ultrasonic bath. The enzymatic reaction was performed using cellulase, α‐amylase, and amyloglucosidase (in separate and combined) on malt bagasse to analyze the hydrolysis effect. For this, a central composite rotational design was applied to evaluate the effect of solid:liquid (malt bagasse w/v) versus enzymatic concentration, considering cellulase, α‐amylase, and amyloglucosidase enzymes in mix solution, on fermentable sugars liberation. Then the kinetic fermentative sugars liberation was evaluated in a hydrolysis reaction using cellulase, α‐amylase, and amyloglucosidase (in separate and combined) after exposure in thermostatic and ultrasonic bath. From enzymatic mix, the maximum total reducing sugar (TRS) yield was 408.8 and 219.9 mg·g−1 in thermostatic and in ultrasound bath, respectively. Kinetic studies showed a TRS variation of 6 to 7 g·L−1 for all enzymes. Amyloglucosidase was more promising in assimilation of malt bagasse, responsible for 43% of sugar releasing. Briefly, a low‐cost procedure using thermostatic bath improved the hydrolysis reaction. The results from the experiments present a new application where malt bagasse can be employed showing the potential of this brewing industry residue in fomenting processes, as bioethanol production. [ABSTRACT FROM AUTHOR]

In developing nations, the use of composite flours in baked products through value addition is increasing. This study investigated the effect of processing variables on the biscuit-making potential of cocoyam-brewer spent grain flour (CYF-BSG) blends. Blends were prepared in ratios (100:0, 90:10, 80:20, and 70:30). Response Surface Methodology consisting of three independent variables at three levels: CYF-BSG (90:10, 80:20, and 70:30) flour blends, mixing time (5, 10 and 15 minutes), and baking time (30, 40, and 50 minutes) were employed to optimize the effects on the biscuits proximate and physical properties. The results showed that moisture, protein, crude fibre, carbohydrates, and ash were significantly (p<0.05) affected by brewer spent grain (BSG) substitution. The protein was significantly (p<0.05) affected by baking time and the interactive effect of mixing and baking time, while the texture was significantly (p<0.05) affected by baking time and the interactive effect of the BSG substitution and mixing time. The spread ratio was significantly (p<0.05) linearly affected by the BSG substitution and the interactive effect of mixing and baking time. The optimum conditions for producing the biscuits based on 65.29% desirability were 25.24% BSG substitution, 13.54 minutes mixing time, and 33.14 minutes baking time at 160 °C baking temperature. This study showed that CYF-BSG flour blends have great potential for biscuit-making [ABSTRACT FROM AUTHOR]

Nowadays, the pandemic situation has encouraged the idea of sustainable healthy foods leading to new trends in food consumption. Brewers spent grain (BSG) represents a potential functional food rich in fiber, protein, lipids, mineral and phenols that needs to be further exploited. In this vein, five different BSG types were collected from local breweries and valorized in cookies manufacturing. Thus, proximate composition (protein, minerals, lipids, ash, crude fiber and carbohydrates) was analyzed using AACC (American Association of Cereal Chemists) methods, DPPH (2,2-Diphenyl-1-picrylhydrazyl), and Folin Ciocalteu methods were used to determined antioxidant activity and total phenols, while minerals and aroma volatile compounds were performed using inductively coupled plasma optical emission spectrometry (ICP-OES) and ITEX/GC-MS (in tube extraction gas chromatography-mass spectrometry) respectively. Color and physical characteristics, together with sensorial analysis, were also evaluated. The results highlighted a significant difference between BSG samples, mainly from the total phenols, antioxidant activity and aroma volatile compounds point of view. BSG volatiles compounds from the aldehydes group such as 2-methyl-propanal, 3-methyl-butanal and 2-methyl-butanal were identified also in the final baked goods, leading to a pleasant and appreciated consumers’ taste and aroma. Furthermore, cookies sensorial analysis emphasized that the sample manufactured with BSG from light and dark malt mixture was more appreciated by consumers, attaining the highest hedonic scores.

Abstract Background Cellulose, the most abundant biopolymer on earth, is an alternative for fossil fuels as a renewable feedstock for the production of second-generation biofuels and other chemicals. The discovery of novel, highly efficient β-glucosidases remains as one of the major bottlenecks for cellulose degradation. In this context, the ascomycete Talaromyces amestolkiae, isolated from cereal samples, has been studied as a promising source for these enzymes. Results BGL-2 is the major β-glucosidase secreted by this fungus in the presence of cellulosic inductors. This enzyme possesses a CBD (Cellulose Binding Domain), an unusual feature among this type of proteins. Besides, when growing on cellulose, the fungus produced two different bgl-2 mRNAs that were cloned and expressed in Pichia pastoris. A complete recombinant protein (BGL-2*) and its truncated form, lacking CBD (BGL-2T*), have been purified, characterized and compared with the native enzyme (BGL-2). The three BGL-2 forms studied are highly stable in a wide pH range, but BGL-2T* showed an improved thermal stability at 50 °C after 72 h. Using p-nitrophenyl-β-d-glucopyranoside as a substrate, the steady-state kinetic characterization of the three proteins showed a similar K m and k cat for BGL-2 and BGL-2*, while the truncated protein displayed a threefold higher value for k cat . All tested BGL-2 enzymes were as well highly efficient using cellobiose and other short oligosaccharides as a substrate. In view of biotechnological applications, the recombinant T. amestolkiae enzymes in saccharification of brewers’ spent grain were studied, being comparable to commercial β-glucosidase cocktails. Conclusion A new β-glucosidase from T. amestolkiae has been studied. The enzyme, containing a functional CBD, has been expressed in P. pastoris. The comparative analyses of the native protein and its recombinant forms, with and without CBD, suggest that they could be suitable tools for valorization of lignocellulosic biomass.

Brewer's spent grain (BSG) is a co-product of the brewing industry and is a potentially rich source of bioactive peptides. A BSG protein hydrolysate, manufactured at a semi-pilot scale, mediated significant hypotensive effects 6 h after ingestion in spontaneously hypertensive rats. This hydrolysate was fractionated and further analysed by UPLC-ESI-MS/MS for peptide identification. The peptides, IPY and LPY demonstrated the highest antioxidant activity (0.37 ± 0.02 and 0.34 ± 0.02 µmol Trolox equivalents µM peptide−1, respectively), IPLQP and LPLQP had the highest ACE inhibitory activity (IC50: 3.10 ± 0.60 and 3.17 ± 0.60 µM, respectively) while IPVP had the highest DPP-IV inhibitory activity (IC50: 38.67 ± 5.94 µM). Overall, peptides containing I had higher in vitro bioactivities when compared to peptides having L. Novel BSG peptides were identified with potential for application as naturally derived ingredients for the management of cardiovascular disease and type 2 diabetes.

Brewers' spent grains (BSG) are underutilized food waste materials produced in large quantities fromthe brewing industry. In this study, solid state fermentation of BSG using Bacillus subtilis WX-17 was carried out to improve the nutritional value of BSG. Fermenting BSG with the strain WX-17, isolated from commercial natto, significantly enhanced the nutritional content in BSG compared to unfermented BSG, as determined by the marked difference in the level of metabolites. In total, 35 metabolites showed significant difference, which could be categorized into amino acids, fatty acids, carbohydrates, and tricarboxylic acid cycle intermediates. Pathway analysis revealed that glycolysis was upregulated, as indicated by the drop in the level of carbohydrate compounds. This shifted the metabolic flux particularly towards the amino acid pathway, leading to a 2-fold increase in the total amount of amino acid from 0.859 ± 0.05 to 1.894 ± 0.1 mg per g of BSG after fermentation. Also, the total amount of unsaturated fatty acid increased by 1.7 times and the total antioxidant quantity remarkably increased by 5.8 times after fermentation. This study demonstrates that novel fermentation processes can value-add food by-products, and valorized food waste could potentially be used for food-related applications. In addition, the study revealed the metabolic changes and mechanisms behind the microbial solid state fermentation of BSG. [ABSTRACT FROM AUTHOR]

Steady consumption of beer results in a steady output of residues, i.e., brewer’s spent grain (BSG). Its valorization, using hydrothermal carbonization (HTC) seems sensible. However, a significant knowledge gap regarding the variability of this residue and its influence on the valorization process and its potential use in biorefineries exists. This study attempted to fill this gap by characterization of BSG in conjunction with the main product (beer), taking into accounts details of the brewing process. Moreover, different methods to assess the performance of HTC were investigated. Overall, the differences in terms of the fuel properties of both types of spent grain were much less stark, in comparison to the differences between the respective beers. The use of HTC as a pretreatment of BSG for subsequent use as a biorefinery feedstock can be considered beneficial. HTC was helpful in uniformization and improvement of the fuel properties. A significant decrease in the oxygen content and O/C ratio and improved grindability was achieved. The Weber method proved to be feasible for HTC productivity assessment for commercial installations, giving satisfactory results for most of the cases, contrary to traditional ash tracer method, which resulted in significant overestimations of the mass yield.

Single-use plastic items made of non-biodegradable and fossil-based materials have been identified as a major environmental problem in modern society. Food packaging materials represent an important fraction of these, and replacement with biosourced, sustainable and low-cost alternatives, is a key priority. In the present work, and for the first time, trays suitable for some food packaging applications were produced by the hot-pressing of brewer’s spent grains (BSG, a low added-value byproduct of the beer industry), bound with potato starch. Expanded polystyrene (EPS) trays were used as reference, since this material has been widely used in food packaging trays. The results demonstrated that all trays produced with varying proportions of BSG and potato starch have appropriate flexural strength, with values ranging between 1.51 ± 0.32 MPa, for 80% BSG content, and 2.62 ± 0.46 MPa, for 40% BSG content, which is higher than for EPS, 0.64 ± 0.50 MPa. Regardless of BSG content, flexural strength and modulus decreased significantly after contact with water, due to starch plasticization, attaining values below EPS. Trays produced with 60% BSG, and also with the addition of chitosan and glyoxal presented the highest flexural strength, both before and after contact with water, 3.75 ± 0.52 MPa and 0.44 ± 0.11 MPa, respectively. The latter is reasonably close to the reference value obtained for EPS.

Background: Cellulose, the most abundant biopolymer on earth, is an alternative for fossil fuels as a renewable feedstock for the production of second-generation biofuels and other chemicals. The discovery of novel, highly efficient β-glucosidases remains as one of the major bottlenecks for cellulose degradation. In this context, the ascomycete Talaromyces amestolkiae, isolated from cereal samples, has been studied as a promising source for these enzymes. Results: BGL-2 is the major β-glucosidase secreted by this fungus in the presence of cellulosic inductors. This enzyme possesses a CBD (Cellulose Binding Domain), an unusual feature among this type of proteins. Besides, when growing on cellulose, the fungus produced two different bgl-2 mRNAs that were cloned and expressed in Pichia pastoris. A complete recombinant protein (BGL-2*) and its truncated form, lacking CBD (BGL-2T*), have been purified, characterized and compared with the native enzyme (BGL-2). The three BGL-2 forms studied are highly stable in a wide pH range, but BGL-2T* showed an improved thermal stability at 50 °C after 72 h. Using p-nitrophenyl-β-dglucopyranoside as a substrate, the steady-state kinetic characterization of the three proteins showed a similar Km and kcat for BGL-2 and BGL-2*, while the truncated protein displayed a threefold higher value for kcat. All tested BGL-2 enzymes were as well highly efficient using cellobiose and other short oligosaccharides as a substrate. In view of biotechnological applications, the recombinant T. amestolkiae enzymes in saccharification of brewers' spent grain were studied, being comparable to commercial β-glucosidase cocktails. Conclusion: A new β-glucosidase from T. amestolkiae has been studied. The enzyme, containing a functional CBD, has been expressed in P. pastoris. The comparative analyses of the native protein and its recombinant forms, with and without CBD, suggest that they could be suitable tools for valorization of lignocellulosic biomass. [ABSTRACT FROM AUTHOR]

Brewers spent grain (BSG) is a widely available feedstock representing approximately 85% of the total by-products generated in the brewing industry. This is currently either disposed of to landfill or used as cattle feed due to its high protein content. BSG has received little or no attention as a potential energy resource, but increasing disposal costs and environmental constraints are now prompting the consideration of this. One possibility for the utilisation of BSG for energy is via intermediate pyrolysis to produce gases, vapours and chars. Intermediate pyrolysis is characterised by indirect heating in the absence of oxygen for short solids residence times of a few minutes, at temperatures of 350–450°C. In the present work BSG has been characterised by chemical, proximate, ultimate and thermo-gravimetric analysis. Intermediate pyrolysis of BSG at 450°C was carried out using a twin coaxial screw reactor known as Pyroformer to give yields of char 29%, 51% of bio-oil and 19% of permanent gases. The bio-oil liquid was found to separate in to an aqueous phase and organic phase. The organic phase contained viscous compounds that could age over time leading to solid tars that can present problems in CHP application. The quality of the pyrolysis vapour products before quenching can be upgraded to achieve much improved suitability as a fuel by downstream catalytic reforming. A Bench Scale batch pyrolysis reactor has then been used to pyrolyse small samples of BSG under a range of conditions of heating rate and temperature simulating the Pyroformer. A small catalytic reformer has been added downstream of the reactor in which the pyrolysis vapours can be further cracked and reformed. A commercial reforming nickel catalyst was used at 500, 750 and 850°C at a space velocity about 10,000L/h with and without the addition of steam. Results are presented for the properties of BSG, and the products of the pyrolysis process both with and without catalytic post-processing. Results indicate that catalytic reforming produced a significant increase in permanent gases mainly (H2 and CO) with H2 content exceeding 50vol% at higher reforming temperatures. Bio-oil yield decreased significantly as reforming temperature increased with char remaining the same as pyrolysis condition remained unchanged. The process shows an increase in heating value for the product gas ranging between 10.8–25.2MJ/m3 as reforming temperature increased. [ABSTRACT FROM AUTHOR]

Purpose: Brewers spent grain (BSG) is a by-product of the brewing process corresponding to around 85% of total by-products generated. The great number of publications over the last 5 years, on the biotechnological applications of BSG, represents the increased scientific interest on it. This critical, state of the art review aims at gathering and analysing the most recent scientific efforts on the biotechnological potential of Brewer's spent grain and on its evaluation as a feedstock for high added value products. Methods: The assiduous bibliographic retrospection focused on the latest scientific reports. The consideration of all relevant scientific articles was thorough and critical. The classification of the scientific efforts was made not only according to the end-products but also according to the biotechnological approach adopted. Results: BSG has been used in a wide range of biotechnological applications such as substrate for enzymes production, as a source for value-added products (antioxidants, monosaccharides, oligosaccharides, xylitol, arabitol, bioethanol, biogas or lactic acid) or for the production of functional proteins and lipids. Its applications as a carrier in various bioprocesses have also been reported. Conclusion: The implementation of BSG's fractionation in industrial scale seems to be the next step in BSG's exploitation. A fractionation process which allows the exploitation of biomolecules belonging to different classes, produced from one feedstock (BSG) may be used as a pattern for the implementation of the biorefinery concept in industrial scale, as long as the methods adopted ensure the functionality of the potentially valuable components. [ABSTRACT FROM AUTHOR]

Abstract: The enzymatic degradation of polysaccharides to monosaccharides is an essential step in bioconversion processes of lignocellulosic materials. Alkali treated brewers spent grain was used as a model substrate for the study of cellulose and hemicellulose hydrolysis by Fusarium oxysporum enzyme extract. The results obtained showed that cellulose and hemicellulose conversions are not affected by the same factors, implementing different strategies for a successful bioconversion. Satisfactory cellulose conversion could be achieved by increasing the enzyme dosage in order to overcome the end-product inhibition, while the complexity of hemicellulose structure imposes the presence of specific enzyme activities in the enzyme mixture used. All the factors investigated were combined in a mathematical model describing and predicting alkali treated brewers spent grain conversion by F. oxysporum enzyme extract. [ABSTRACT FROM AUTHOR]

The first lytic polysaccharide monooxygenase (LPMO) detected in the genome of the widespread ascomycete Talaromyces amestolkiae (TamAA9A) has been successfully expressed in Pichia pastoris and characterized. Molecular modeling of TamAA9A showed a structure similar to those from other AA9 LPMOs. Although fungal LPMOs belonging to the genera Penicillium or Talaromyces have not been analyzed in terms of regioselectivity, phylogenetic analyses suggested C1/C4 oxidation which was confirmed by HPAEC. To ascertain the function of a C-terminal linker-like region present in the wild-type sequence of the LPMO, two variants of the wild-type enzyme, one without this sequence and one with an additional C-terminal carbohydrate binding domain (CBM), were designed. The three enzymes (native, without linker and chimeric variant with a CBM) were purified in two chromatographic steps and were thermostable and active in the presence of H2O2. The transition midpoint temperature of the wild-type LPMO (Tm = 67.7 °C) and its variant with only the catalytic domain (Tm = 67.6 °C) showed the highest thermostability, whereas the presence of a CBM reduced it (Tm = 57.8 °C) and indicates an adverse effect on the enzyme structure. Besides, the potential of the different T. amestolkiae LPMO variants for their application in the saccharification of cellulosic and lignocellulosic materials was corroborated. [ABSTRACT FROM AUTHOR]

In this study, the ethanol production by the mesophilic fungus Neurospora crassa from BG was studied and optimized concerning the induction of lignocellulose degrading enzymes and the production phase as well. The production of cellulolytic and hemicellulolytic enzymes was studied under solid-state cultivation (SSC). SSC in a laboratory horizontal bioreactor using the optimized medium, WS and BG in the ratio 1:1 and initial moisture level 61.5%, allowed the large scale production of the multienzymatic system. Similar yields with those from flasks experiments, as high as 1073,56,4.2,1.6,3.1,5.7 and 0.52Ug−1 carbon source of xylanase, endoglucanase, cellobiohydrolase, β-glucosidase, α-l-arabinofuranosidase, acetyl esterase and feruloyl esterase, respectively, were obtained. Chromogenic (fluorogenic) 4-methylumbelliferyl substrates were used to characterize the major activities of the multienzyme component, after the separation by isoelectric focusing (IEF) electrophoresis. Alkali pre-treated BG was used for ethanol production. A yield of about 74g of ethanolkg−1 dry BG (5,6gL−1) was obtained under optimum conditions (aeration 0.1vvm, pre-treatment with 1g NaOH 10g−1 dry BG). [Copyright &y& Elsevier]

Abstract: Brewer''s spent grain (BG), the most abundant brewing by-product, is used in the present study as a low-cost feedstock for the production of ethanol by the mesophilic fungus Fusarium oxysporum using a consolidated bioconversion process. The production of required cellulolytic and hemicellulolytic enzymes was optimized under solid-state cultivation (SSC) concerning carbon source and initial moisture. The optimal medium contains BG and corn cobs (CC) in a ratio 7:3 while the optimal initial moisture is 66% (w/w). SSC in a laboratory horizontal bioreactor using the optimized medium allowed the large-scale production of a multienzymic system including endoglucanase, cellobiohydrolase, β-d-glucosidase, xylanase, feruloyl esterase, acetyl esterase, β-d-xylosidase and α-l-arabinofuranosidase. Chromogenic (fluorogenic) 4-methylumbelliferyl substrates were used to partially characterize the extracellular proteome of the microbe after the separation by isolectric focusing (IEF) electrophoresis. Alkali pretreatment of brewer''s spent grain and different aeration levels were studied for the optimization of the ethanol production by F. oxysporum in a consecutive submerged fermentation. A yield about 65gethanolkg−1 of dry BG was obtained with alkali pretreated BG under microaerobic conditions (0.01vvm) corresponding to 30% of the theoretical yield based on total glucose and xylose composition of BG. [Copyright &y& Elsevier]

Abstract: The effect of screw speed (100–300rpm) and addition of brewers spent grain (BSG, 0–30% based on the maize flour used) on the approximate composition (crude protein, crude fat, total starch, crude fibre), physical (expansion, hardness, bulk density, SME, water absorption and solubility indexes), nutritional (total antioxidant capacity, TAC; total phenolic compounds, TPC; phytic acid, PA; protein in vitro digestibility, PIVD; resistant starch, RS) and colour (Hunter L, a, b) properties of an extruded snack food was investigated. A decrease in hardness was observed at increased screw speeds whereas scattered data was obtained with increasing BSG levels. Results indicated that addition of BSG resulted in reduced expansion and increased PA, PIVD and RS values (P <0.05). On the other hand, addition of BSG to the samples has no significant effect on the TAC and TPC values (P <0.05). Increased screw speeds resulted in increased expansion and decreased RS values (P <0.05). Screw speed has no significant effect on the TAC, TPC, colour, PA and PIVD values of BSG added samples (P <0.05). Addition of BSG caused a decrease in the Hunter L values giving darker samples. [Copyright &y& Elsevier]

Nowadays, the pandemic situation has encouraged the idea of sustainable healthy foods leading to new trends in food consumption. Brewers spent grain (BSG) represents a potential functional food rich in fiber, protein, lipids, mineral and phenols that needs to be further exploited. In this vein, five different BSG types were collected from local breweries and valorized in cookies manufacturing. Thus, proximate composition (protein, minerals, lipids, ash, crude fiber and carbohydrates) was analyzed using AACC (American Association of Cereal Chemists) methods, DPPH (2,2-Diphenyl-1-picrylhydrazyl), and Folin Ciocalteu methods were used to determined antioxidant activity and total phenols, while minerals and aroma volatile compounds were performed using inductively coupled plasma optical emission spectrometry (ICP-OES) and ITEX/GC-MS (in tube extraction gas chromatography-mass spectrometry) respectively. Color and physical characteristics, together with sensorial analysis, were also evaluated. The results highlighted a significant difference between BSG samples, mainly from the total phenols, antioxidant activity and aroma volatile compounds point of view. BSG volatiles compounds from the aldehydes group such as 2-methyl-propanal, 3-methyl-butanal and 2-methyl-butanal were identified also in the final baked goods, leading to a pleasant and appreciated consumers' taste and aroma. Furthermore, cookies sensorial analysis emphasized that the sample manufactured with BSG from light and dark malt mixture was more appreciated by consumers, attaining the highest hedonic scores. [ABSTRACT FROM AUTHOR]

In today's society, we can see a progressive paradigm shift that tends towards a healthy and sustainable lifestyle. The proof is represented by the growing interest in food loss and waste of different sectors, from the political to the academic, or even to the private sector. In order to reduce food waste and to increase sustainability, the European Union (EU) has planned a circular bioeconomy. This action plan includes an approach based on reducing, reusing, recovering, and recycling materials and energy. Every year, there are high amounts of waste and by-products resulting from agricultural producing and agro-industrial processing, impacting the environment and the socio-economic sector. Cereal food products cover over 20% of daily diet, so it can be assumed that cereal production and processing are one of the most important sectors of agri-food industries. It is estimated that the waste generated from cereal processing and manufacturing is up to 13%, a percentage that can be decreased by converting the by-products in raw materials for biofuels, biodegradable plastics, alcohols, antioxidants, food additives, or pharmaceutic ingredients due to their content in macro- and micro-nutrients or bioactive compounds. Based on the fact that diet plays a crucial role in maintaining the integrity of our body, it is important to capitalize on any source of bioactive compounds to which we have access. This review aims to highlight the need to recirculate by-products for the purpose of extraction and use of their key compounds, polyphenols, which have not only antioxidant effects, but also preventive and therapeutic effects against cancer. For these, it is necessary to understand the biotechnologies needed for processing the most consumed cereals, the methods of extraction of phenolic compounds, and the main effects that these compounds have, summarizing the most relevant in vitro and in vivo studies performed so far. [ABSTRACT FROM AUTHOR]

• Subcritical water was applied to brewer's spent grain. • High protein recovery was achieved by hydrolysis of the peptide bonds. • Fractionation of biocompounds can be achieved by selecting operating temperature. • Polar amino acids were more sensitive to temperature than non-polar amino acids. • Hydroxycinnamic acids were more sensitive to temperature than aldehyde phenolics. The valorization of the brewer's spent grain (BSG) generated in a craft beer industry was studied by subcritical water hydrolysis in a semi-continuous fixed-bed reactor. Temperature was varied from 125 to 185 °C at a constant flow rate of 4 mL/min. Biomass hydrolysis yielded a maximum of 78% of solubilized protein at 185 °C. Free amino acids presented a maximum level at 160 °C with a value of 55 mg free amino acids/g protein-BSG. Polar amino acid presented a maximum at lower temperatures than non-polar amino acids. The maximum in total phenolic compounds was reached at 185 °C. This maximum is the same for aldehyde phenolic compounds such as vanillin, syringic and protocatechuic aldehyde; however, for hydroxycinnamic acids, such as ferulic acid and p-coumaric, the maximum was obtained at 160 °C. This allows a fractionation of the bioactive compounds. Subcritical water addresses opportunities for small breweries to be incorporated within the biorefinery concept. [ABSTRACT FROM AUTHOR]