Brewery Spent Grain Research Articles

Effect of brewery spent grain on the growth and yield of sorghum (Sorghum bicolor (l.) Moench)

A field experiment was conducted at the Teaching and Research Farm, Ambrose Alli University, Ekpoma to investigate the effect of brewery spent grain on the growth and yield of sorghum. Treatment consisted of five rates of brewery spent grain (BSG) (0, 2, 4, 6 and 8 t/ha). The experiment was a randomized complete block design (RCBD) with three replicates. Sorghum variety (ABS 4540 AMZU) was used as a test crop. The parameters measured included: plant height, leaf area, number of leaves/plant at 3, 6 and 9 weeks after planting (WAP). Whole plant dry matter yield and grain weight were also determined. The results obtained showed that BSG treatments had significantly (P<0.05) higher plant height, leaf area and number of leaves than the control in all the weeks after planting, except for number of leaves at 3 WAP. At 3 and 6 WAP, the tallest plants (21.33 cm and 33.05 cm) were obtained from crops treated with 8 t/ha BSG while those treated with 6 t/ha BSG had the tallest plant (95.04 cm) at 9 WAP. 6 t/ha BSG recorded the highest leaf area at 3, 6 and 9 WAP. At 6 WAP, the highest number of leaves (9.00) was observed from plants which received the application of 6 t/ha BSG. However, control had the highest number of leaves (10.00) than BSG treatments. The highest grain yield (2.54 t/ha) and dry matter yield (3.80 g) were obtained from crops which received the application of 6 and 8 t/ha BSG, respectively. Keywords: Brewery Spent Grain, Growth, Sorghum, Yield.

Ascorbic Acid Production by Aspergillus flavus and Aspergillus tamarii; Kinetic and Thermodynamic Study.

This study investigated the fermentation kinetics and thermodynamics of ascorbic acid production from Brewery Spent Grain (BSG) using Aspergillus flavus and Aspergillus tamarii. Ascorbic acid fermentation of A. flavus and A. tamarii was performed at a temperature of 30°C, agitation speed of 100rpm and pH 5.0 at 96h of fermentation. The thermodynamics, kinetics of the growth parameters and ascorbic acid production were studied using Monod, Contois and Teisser models. Teisser model gave the best fit as it obtained the highest maximum specific growth rate (µmax) and correlation coefficient of 0.184h-1 and 0.997, respectively, at 40°C, pH 5.0 and 0.6g of BSG. The result showed that Teisser model gave a better description of each growth parameter. Hence, the production of ascorbic acid by A. flavus and A. tamarii is growth-associated.

Thermophilic Co-Digestion of Sewage Sludge and Brewery Spent Grain

Thermophilic Co-Digestion of Sewage Sludge and Brewery Spent Grain

Enhancing the co-digestion efficiency of sewage sludge and cheese whey using brewery spent grain as an additional substrate

This study examined the influence of the application of brewery spent grain (BSG) on biogas production efficiency as well as its kinetics in the co-digestion of acid cheese whey (ACW) and sewage sludge (SS). The experiment was conducted in semi-flow anaerobic reactors under mesophilic conditions (35 °C) with different hydraulic retention times (HRT) of 16.7 d, 18 d and 20 d. The results indicate that the addition of BSG significantly enhanced the biogas yields, ensuring good process stability. The highest value of 0.54 m3 kg−1 VSadded was obtained at HRT of 16.7 d, while for ACW and SS it was only 0.50 m3 kg−1 VSadded at HRT 18 d. However, the decrease in the rate constant k occurred (0.07 h−1) as compared to the two-component system (0.096 h−1). The highest energy profit of 160% was enhanced for the three-substrate co-digestion, indicating it as a cost-effective solution.

A novel approach to the biorefinery of brewery spent grain

• Brewery spent grain can be effectively used through a three-steps biorefining process. • A cost-effective enzymatic cocktail can be produced with A. brasiliensis . • Cholinium glycinate IL improves the hydrolysis of carbohydrate-rich materials. • Complete lignin removal is not necessary to achieve a good polysaccharides hydrolysis. This article describes a new three-step biorefinery process for the complete fractionation of brewery spent grain (BSG). First, BSG was assessed as a substrate for the production of enzymatic cocktails, mainly xylanases, through solid-state fermentation with Aspergillus brasiliensis . Second, the spent solid residue (SSR) recovered was delignified with cholinium glycinate ionic liquid, reducing the Klason lignin by 75.26% and the soluble lignin by 62.92%. In addition, scanning electron microscopy of the carbohydrate-rich material (CRM) showed some microfibrils and pores, which facilitated the diffusion of enzymes. Third, an enzymatic hydrolysis of the CRM was assayed with Aspergillus extracts and commercial enzyme preparations, such as Ultraflo L ® , to release fermentable sugars under non-optimized conditions. Preliminary results showed that Ultraflo L ® and Aspergillus extract have similar yields in the hydrolysis of glucans and xylans in BSG. No xylose, and only low amounts of glucose, were released from the SSR. Meanwhile, an improvement of the enzymatic hydrolysis in CRM was noted through the increase in saccharification of all fractions, this reaching xylan at 54.37% when Aspergillus extract was used. Although more experimental research is needed to optimize the enzymatic hydrolysis, these results illustrate the clear benefits of the integrated process proposed.

Strain improvement of <i>Aspergillus flavus</i> for enhanced ascorbic acid production by physical and chemical mutagenesis

The demand for ascorbic acid in the food and pharmaceutical industry led to the search for hyper ascorbic acid producing strains by physical and chemical mutagenesis. Spores of Aspergillus flavus were subjected to Ultraviolet (UV) radiation (240 nm) and Ethidium Bromide (EB) (25, 50, 75 and 100 μg/ml) to develop hyper-producing mutants. The selected mutants were cultured in a liquid fermentation medium containing Brewery Spent Grain (0.6 % w/v) at pH range 4 - 8, temperature range 30 - 45 °C, agitation speed range 60 - 160 rpm for 96 h. Ascorbic acid produced was quantified by titration techniques and with High Performance Liquid Chromatography (HPLC). The UV and EB mutant strains of A. flavus gave increased ascorbic acid yields of 6.99 g/L and 7.28 g/L respectively when compared to the parental strain with ascorbic acid yield of 3.92 g/L. Optimum ascorbic acid yields were produced at 40 °C, pH 5.0 and 100 rpm at 96 h of fermentation. This study shows the potential of strain improvement for enhanced ascorbic acid production. Keywords: Ascorbic acid; Ethidium bromide; Ultraviolet radiation; Aspergillus flavus; Mutagenesis

Comparative Studies on the Bioremediation of Used Engine Oil Contaminated Soil using Urea Fertilizer (UF), Goat Manure (GM), Pig Manure (PM) and Brewery Spent Grain (BSG)

The focus of the study was to evaluate and compare the performance of urea fertilizer, goat manure, pig manure and brewery spent grain for the bioremediation of used engine oil contaminated soil. Soil with no pollution history was collected and subjected to detailed laboratory analysis to determine the total heterotrophic bacterial population, pH, moisture content, total organic carbon, total nitrogen and total hydrocarbon content. Used engine oil contaminated soil was prepared by adding 250g of used engine oil into a clean dry plastic bucket containing 1kg of unpolluted soil. The mixture was properly mixed and covered with aluminium foil paper before use. The used engine oil contaminated soil was left for a period of four (4) days for stabilization before the commencement of treatment. The entire setup and its content was open throughout the period of experimentation to allow for the influence of atmospheric oxidation. The setup was monitored for twelve (12) weeks and sampling/analysis of the samples was done on a weekly basis to ascertain the progress of treatment. The residual hydrocarbon content after each treatment was determined using Atomic Absorption Spectrophotometer. Results obtained shows that pig manure is the best substrate for the clean-up of used engine oil contaminated soil with calculated removal efficiency of 64.4% followed by BSG with 51.4% removal efficiency, Goat Manure with removal efficiency of 39.9% and Urea Fertilizer with 33.7% efficiency. The kinetic modelling shows that experimental data fitted well with pseudo-first order kinetic model with calculated error sum of square (SSE) values of (0.0002, 0.0005, 0.0012 and 0.0072) and root mean square errors (RMSE) of (0.0028, 0.0073, 0.0082 and 0.0481). On the accurate prediction of the optimum remediation time, it was observed that the non-linear regression model gave higher coefficient of determination of 0.9824, 0.9812, 0.9886 and 0.9899 compared to linear regression.

Effects of Dietary Brewery Spent Grain Inclusion on Egg Laying Performance and Quality Parameters of Bovans Brown Chickens

ABSTRACT Poultry rations are composed mainly of conventional cereal grains and proteins. Using non-conventional agro-industrial by-products may reduce the cost of production and thereby improve productivity. A study was conducted to evaluate the effect of dietary brewery spent grain inclusion on egg laying performance, quality parameters of bovans brown and profitability of the rations. A total of 200 pullets with similar body weight and age were randomly distributed to five treatments with four replications. The treatments were brewery spent grain (BSG) inclusion of 0, 10, 20, 30 and 40% levels for T1, T2, T3, T4 and T5, respectively. The CP and ME contents of treatment rations were 16.54-17.04% and 2871-2903 kcal/kg DM, respectively. Inclusion of the BSG in the layers ration did not affect dry matter intake, feed conversion efficiency and hen-day egg production (58.79, 57, 56.11, 55.11 and 54.13% (SEM=0.92)). Likewise, the inclusion of the BSG in the diets did not affect (albumen, yolk, shell) quality. However, feed cost decreased with the increasing level of the BSG in the rations because of its lower purchasing price. To conclude, a 40% inclusion of BSG in the diet of layers does not affect the production and the quality of the eggs and it can be economically profitable.

Biorefining brewery spent grain polysaccharides through biotuning of ionic liquids

Brewery spent grain (BSG), a relevant waste from beer industry mainly composed of polysaccharides and lignin, is experiencing a surge in the production with its associated environmental impact. Thus, this manuscript bets in the application of aqueous solutions of a cholinium-based ionic liquid (IL) containing glycinate as anion ([N1112OH][Gly]) for an efficient delignification pretreatment. The operation at 90 °C yielded drastic lignin reduction (75.89%), greater than the levels attained when a traditional imidazolium-based IL (1-ethyl-3-methylimidazolium acetate, [C2C1im][C1COO]), was used (40.18%). The advantages of this pretreatment positively impacted the subsequent saccharification reaction, as the levels were increased up to about 1.5 times regarding the control (no IL) or the imidazolium-based pretreatment. ATR-FTIR spectrometry and scanning electron microscopy turned out to be useful tools to monitor the structural changes exerted. The results presented in this work make up the basis for a rational design of bio-ILs for delignification of lignocellulosic materials.

Microwave-assisted one-pot conversion of agro-industrial wastes into levulinic acid: An alternate approach

Brewery liquid waste (BLW), brewery spent grain (BSG), apple pomace solid wastes (APS), apple pomace ultrafiltration sludge (APUS) and starch industry waste (SIW) were evaluated as alternative feedstocks for levulinic acid (LA) production via microwave-assisted acid-catalyzed thermal hydrolysis. LA production of 204, 160, 66, 49 and 12 g/kg was observed for BLW, BSG, APS, APUS, and SIW, respectively, at 140 °C, 40 g/L substrate concentration (SC), 60 min and 2 N HCl (acid concentration). Based on the screening studies, BLW and BSG were selected for optimization studies using response surface methodology. Maximum LA production of 409 and 341 g/kg for BLW and BSG, respectively were obtained at 160 °C, 4.5 M HCl, 85 g/L SC and 27.5 min. Results demonstrated the possibility of using brewery wastes as promising substrates for economical and higher yield production of LA, a renewable platform chemical and versatile precursor for fuels and chemicals.

Effect of Inoculum Type on Anaerobic Co-Digestion of Palm Oil Mill Effluent and Brewery Spent Grain for Biogas Production

Effect of Inoculum Type on Anaerobic Co-Digestion of Palm Oil Mill Effluent and Brewery Spent Grain for Biogas Production

Hydrolytic pre-treatment methods for enhanced biobutanol production from agro-industrial wastes

Brewery industry liquid waste (BLW), brewery spent grain (BSG), apple pomace solid wastes (APS), apple pomace ultrafiltration sludge (APUS) and starch industry wastewater (SIW) have been considered as substrates to produce biobutanol. Efficiency of hydrolysis techniques tested to produce fermentable sugars depended on nature of agro-industrial wastes and process conditions. Acid-catalysed hydrolysis of BLW and BSG gave a total reducing sugar yield of 0.433 g/g and 0.468 g/g respectively. Reducing sugar yield from microwave assisted hydrothermal method was 0.404 g/g from APS and 0.631 g/g from APUS, and, 0.359 g/g from microwave assisted acid-catalysed SIW dry mass. Parameter optimization (time, pH and substrate concentration) for acid-catalysed BLW hydrolysate utilization using central composite model technique produced 307.9 g/kg glucose with generation of inhibitors (5-hydroxymethyl furfural (20 g/kg), furfural (1.6 g/kg), levulinic acid (9.3 g/kg) and total phenolic compound (0.567 g/kg)). 10.62 g/L of acetone-butanol-ethanol was produced by subsequent clostridial fermentation of the substrate.

Two-phase partitioning detoxification to improve biobutanol production from brewery industry wastes

An efficient, rapid, ex-situ two phase partitioning detoxification has been developed to reduce inhibitor concentration in biomass hydrolysate and enhance biobutanol production from brewery liquid waste (BLW) and brewery spent grain (BSG). About 80±2.0% extraction of furan derivatives and more than 95±2.0% extraction of phenolic compounds and almost no extraction of reducing sugar from simulated synthetic media as well as real waste hydrolysate have made this method more interesting. Detoxification of brewery liquid waste and brewery spent grain hydrolysate by over liming and charcoal gave biobutanol production of 4.3g/L, 6.3g/L and 4.6g/L, 5.8g/L respectively. Ex-situ extraction of microbial inhibitors from brewery liquid waste and brewery spent grain hydrolysates using bis (2-ethylhexyl sebacate) as extractant gave biobutanol production of 8.0g/L and 7.2g/L respectively. Lower power consumption (0.081W/L) and reuse of the extracting solvent made this detoxification technique extremely useful for improving production of biobutanol from agro-industrial waste.

Phytoremediation Potential of Kenaf (Hibiscus Cannabinus) in Soil Contaminated with Used Lubricating Oil

Soil and groundwater contamination incidences with petroleum and petrochemical based products are growing in frequency and quantity. One example is used lubricating oil from machineries. There is a growing demand to remediate the contaminated soil with in-situ phytoremediation. Therefore in this work, Hibiscus cannabinus was investigated for its potential to remove hydrocarbon and heavy metals from soil contaminated with 2.5% and 1% used lubricating oil and amended with organic wastes [banana skin (BS), brewery spent grain (BSG) and spent mushroom compost(SMC)] for a period of 90 days. Loss of 86.4% and 91.8% used lubricating oil was recorded in soil contaminated with 2.5% and 1% oil and amended with organic wastes respectively at the end of 90 days. However, 52.5% and 58.9% oil loss was recorded in unamended soil contaminated with 2.5% and 1% oil, respectively. The plant did not accumulate hydrocarbon from the soil but shows appreciable accumulation of Fe and Zn in the root and stem. 47.0 mg/kg and 2.37 mg/kg of Fe accumulated in the root and stem while 1.5 mg/kg and 1.64 mg/kg of Zn accumulated in roots and stems of H. cannabinus respectively at the end of the experiment. The results of this study suggest that H. cannabinus has high potential for remediation of hydrocarbon and heavy metal contaminated soil.

Anaerobic Biodegradation of Raw and Pre-treated Brewery Spent Grain Utilizing Solid State Anaerobic Digestion.

The brewery spent grain (BSG) represents approximately 85% of the total quantity of by-products from the brewing industry. The biogas production from the BSG has been the subject of several studies in recent years, due to relatively high energy consumption in the brewing process and due to the increasing energy costs. The biodegradability of raw and pre-treated BSG in a single-stage and two-stage solid-state anaerobic digestion (SS-AD) system was determined in this study. The results show that the BSG have a biogas potential of 120 L/kg(-1). In the single-stage system, the biogas yield obtained from raw BSG (87.4 L/kg(-1)) was almost equal to the yield obtained from the pre-treated BSG (89.1 L/kg(-1)), while the methane yield was 51.9 and 55.3 L/kg(-1) and the biodegradation was 62.0% and 62.2% for raw and pre-treated BSG, respectively. In two-stage SS-AD the pre-treated BSG showed better results, with the biogas yield of 103.2 L/kg(-1) and the biodegradation of 73.6%, while the biogas yield obtained from raw BSG was 89.1 L/kg(-1), with the biodegradation of 63.5%. In two-stage process the obtained methane yields from raw and pre-treated BSG were identical (58.7 L/kg(-1)).

ENHANCING METHANE OXIDATION IN LANDFILL COVER USING BREWERY SPENT GRAIN AS BIOCOVER

Landfill gas (LFG) is a potent greenhouse gas (GHG) generated by anaerobic degradation of decomposable municipal solid wastes (MSW). LFG contains (50-60%) of methane (CH4) and (40–50%) carbon dioxide (CO2). If a landfill is neither aerated nor equipped with gas capture systems, the LFG emissions, mainly CH4, in the cover soil is best reduced by using a biocover. Biocovers normally act as a biofilter to reduce emissions by improving the biological oxidation of CH4 to CO2. In this study, the optimal ratio for a biocover using mixture of brewery spent grain (BSG) and compost made out of grass and cow manure is determined. Thereafter, column experiments were carried out to investigate the best height level of the biocover. Batch incubation experiments were conducted for screening the best ratio of BSG to compost. A mixing ratio from 10% to 100% BSG to compost with 10% increment was tested. The best ratio of BSG to compost was 7:3. This ratio was later tested with different parameters such as pH, moisture content and temperature. Overall, the optimum biocover performance was at pH 6, moisture content of 66% (v/v) and temperature of 40°C. The column experiments showed that 100% CH4 oxidation occurred fastest at the height of 50cm. (Keywords: Greenhouse gas, methane oxidation, biocover, brewery spent grain, compost)

Biodegradation of Used Motor Oil in Soil Using Organic Waste Amendments

Soil and surface water contamination by used lubricating oil is a common occurrence in most developing countries. This has been shown to have harmful effects on the environment and human beings at large. Bioremediation can be an alternative green technology for remediation of such hydrocarbon-contaminated soil. Bioremediation of soil contaminated with 5% and 15% (w/w) used lubricating oil and amended with 10% brewery spent grain (BSG), banana skin (BS), and spent mushroom compost (SMC) was studied for a period of 84 days, under laboratory condition. At the end of 84 days, the highest percentage of oil biodegradation (92%) was recorded in soil contaminated with 5% used lubricating oil and amended with BSG, while only 55% of oil biodegradation was recorded in soil contaminated with 15% used lubricating oil and amended with BSG. Results of first-order kinetic model to determine the rate of biodegradation of used lubricating oil revealed that soil amended with BSG recorded the highest rate of oil biodegradation (0.4361 day−1) in 5% oil pollution, while BS amended soil recorded the highest rate of oil biodegradation (0.0556 day−1) in 15% oil pollution. The results of this study demonstrated the potential of BSG as a good substrate for enhanced remediation of hydrocarbon contaminated soil at low pollution concentration.

Phytotreatment of soil contaminated with used lubricating oil using Hibiscus cannabinus

Soil contamination by hydrocarbons, especially by used lubricating oil, is a growing problem in developing countries, which poses a serious threat to the environment. Phytoremediation of these contaminated soils offers environmental friendly and a cost effective method for their remediation. Hibiscus cannabinus was studied for the remediation of soil contaminated with 2.5 and 1% used lubricating oil and treated with organic wastes [banana skin (BS), brewery spent grain (BSG) and spent mushroom compost (SMC)] for a period of 90days under natural conditions. Loss of 86.4 and 91.8% used lubricating oil was recorded in soil contaminated with 2.5 and 1% oil and treated with organic wastes respectively at the end of 90days. However, 52.5 and 58.9% oil loss was recorded in unamended soil contaminated with 2.5 and 1% oil, respectively. The plant did not accumulate hydrocarbon from the soil but shows appreciable accumulation of Fe and Zn in the root and stem of H. cannabinus at the end of the experiment. The first order kinetic rate of uptake of Fe and Zn in H. cannabinus was higher in organic wastes amendment treatments compared to the unamended treatments, which are extremely low. The results of this study suggest that H. cannabinus has a high potential for remediation of hydrocarbon and heavy metal contaminated soil.

Phytoaccumulation of zinc and iron by Jatropha curcas grown in used lubrication oil-contaminated soil

Contamination of soil by heavy metals from used lubricating oil constitutes major environmental problems due to its negative impacts on humans and environment. Plants that possessed bioaccumulation potential offered green remediation approach for the removal of such heavy metal contaminants. In this study, heavy metal accumulation potential of Jatropha curcas was studied in soil contaminated with 2.5% and 1% (w/w) used lubricating oil and enhanced with organic wastes [banana skin (BS), brewery spent grain (BSG) and spent mushroom compost (SMC)] for 180 days under room condition. At the end of 180 days, accumulation of Fe and Zn were recorded in J. curcas tissues (roots, stems and leaves) in all the treatments. 9.94 mg/kg to 26.34 mg/kg of Fe and 4.14 mg/kg to 8.45 mg/kg of Zn were recorded in the roots of J. curcas in soil contaminated with 2.5% oil. Organic wastes amendments enhanced the bioaccumulation of Fe and Zn with about 25% compared with control treatments without organic wastes amendment. The result of this study suggests that J. curcas has a good potential for bioaccumulation of Fe and Zn in contaminated soil.

Brewery Spent Grain: Chemical Characteristics and utilization as an Enzyme Substrate

Grains in a brewery that have been removed of their sugar content is classified as a byproduct known as spent grain. It is a low-cost material and is available year-round. In Malaysia, approximately 15% of brewery spent grain (BSG) that is produced is salvaged and sold as feedstock supplement, while the remainder is discarded in landfills. This is a waste of a potentially useful resource. The chemical composition of fresh BSG was studied. Nine species of fungi were individually inoculated onto sterile BSG and solid state fermentation occurred without chemical adjustment or supplementation. Activity of laccase, lignin peroxidase, xylanase, amylase, carboxymethyl cellulase, protease and tannase was assayed. BSG consists of lignin and cellulose. High enzyme activity of laccase was shown by Pleurotus sajor-caju, Penicillium chrysogenum, and Aspergillus niger. This study is possibly the first to report laccase activity by solid state fermentation of spent grain.