Food Industry By-products Research Articles

Insight on açaí seed biomass economy and waste cooking oil: Eco-sorbent castor oil-based

The reuse of açaí seeds is an organic approach for valorizing biomass, encouraging the public policies of circular economy, which reduces the human impact on the production chain processes. This research proposes an alternative for açaí seed as a filler in castor oil-based polyurethane, obtaining eco-sorbent to evaluate the sorption capacity for another impactful food industry by-product: waste cooking oil (WCO). Eco-sorbents were obtained with castor oil based-polyol and isocyanate (MDI) by mass mixing equal to 1:1 (OH:NCO), reinforced with açaí seed residue (5–20 wt%). The samples were characterized by techniques scanning electron microscopy (SEM), optical microscopy (OM), apparent density, contact angle, infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Sorption capacity and efficiency were evaluated as a function of the fiber content, with tests performed in times of 30–180 s in two systems: oil and oil/water. The results showed that the eco-sorbents had a hydrophobic nature (θ > 98.3°) and macroporous morphology (pore size from 152 to 119 μm), which allowed the adsorption of residual cooking oil by the porous structure. The kinetics study showed that the sample with greater fiber content (15% wt.) reached the equilibrium in a short time compared to the neat PU for the oil system, with a sorption capacity of 9.50 g g−1 in the first 30 s. For the oil/water system, an opposite behavior could be observed, with a sorption capacity of 9.98 g g−1 in the 150 s equilibrium time. The Langmuir isotherm model presented a maximum adsorption capacity of 10.42 g g−1. However, the Freundlich isotherm model had a better fit to the experimental data with R2 (0.97) and lower chi-square (0.159), showing favorable adsorption (n = 1.496). Thus, it was proved that the weak interactions (connection H) and the binding energy of the predominant physisorption for the oil/water system. Thus, developed eco-sorbents are an excellent option for the sorption of WCO.

Biodegradable Chitosan Films with ZnO Nanoparticles Synthesized Using Food Industry By-Products—Production and Characterization

This work aimed to produce bionanocomposites of chitosan incorporated with zinc oxide nanoparticles (ZnO NPs) synthesized using food industry by-products and to characterize them. Such nanoparticles are highlighted due to their low cost, antimicrobial activity, accessibility, and sustainability synthesis. Four different levels of ZnO NPs (0, 0.5, 1.0, and 2.0% w/w of chitosan) were tested, and the bionanocomposites were characterized in terms of their hydrophobicity, mechanical, optical, and barrier properties. Overall, the incorporation of ZnO NPs changed the composites from brittle to ductile, with enhanced elongation at break and reduced Young Modulus and tensile strength. Thus, ZnO NPs acted as plasticizer, turning the films more flexible, due to the presence of organic compounds on the NPs. This also favored permeability of oxygen and of water vapor, but the good barrier properties were maintained. Optical properties did not change statistically with the ZnO NPs incorporation. Thus, the characterization presented in this paper may contribute to support a decision on the choice of the material’s final application.

Evaluation of Chitosan Modified by Acidic Deep Eutectic Solvents in the Extraction of Flavonoids from Sea Buckthorn (Hippophae Rhamnoides L.) Leaves

Eight deep eutectic solvents composed of choline chloride and various acids were used to synthesize chitosan derivatives. All acidic deep eutectic solvents resulted in high transmittance and stable chitosan derivatives under the appropriate reaction conditions. Choline chloride–oleic acid–chitosan provided the best performance and was used for the ultrasound-assisted extraction of rutin, quercetin, and isorhamnetin from sea buckthorn (Hippophae rhamnoides L.) leaves coupled with reversed-phase high-performance liquid chromatography (RP-HPLC). The extraction provided recoveries of 107.5 ± 0.16 rutin, 30.22 ± 0.37 quercetin, and 43.5 ± 0.22 isorhamnetin mg g−1 dry powder using the optimal conditions at 41 °C, solid/solvent ratio of 1:24 g mL−1, and six adsorption/desorption cycles. The linear range was from 1.0 to 1000.0 µg mL−1 and the limits of detection (LODs) for rutin, quercetin, and isorhamnetin were 0.12, 0.16, and 0.23 µg g−1, respectively. The results showed that sea buckthorn (H. rhamnoides L.) leaves, a food industry by-product, may be used as an inexpensive source of flavonoids.

Increasing the Content of Olive Mill Wastewater in Biogas Reactors for a Sustainable Recovery: Methane Productivity and Life Cycle Analyses of the Process.

Anaerobic codigestion of olive mill wastewater for renewable energy production constitutes a promising process to overcome management and environmental issues due to their conventional disposal. The present study aims at assessing biogas and biomethane production from olive mill wastewater by performing biochemical methane potential tests. Hence, mixtures containing 0% (blank), 20% and 30% olive mill wastewater, in volume, were experimented on under mesophilic conditions. In addition, life cycle assessment and life cycle costing were performed for sustainability analysis. Particularly, life cycle assessment allowed assessing the potential environmental impact resulting from the tested process, while life cycle costing in conjunction with specific economic indicators allowed performing the economic feasibility analysis. The research highlighted reliable outcomes: higher amounts of biogas (80.22 ± 24.49 NL.kgSV−1) and methane (47.68 ± 17.55 NL.kgSV−1) were obtained when implementing a higher amount of olive mill wastewater (30%) (v/v) in the batch reactors. According to life cycle assessment, the biogas ecoprofile was better when using 20% (v/v) olive mill wastewater. Similarly, the economic results demonstrated the profitability of the process, with better performances when using 20% (v/v) olive mill wastewater. These findings confirm the advantages from using farm and food industry by-products for the production of renewable energy as well as organic fertilizers, which could be used in situ to enhance farm sustainability.

Food Industry By-Products as Raw Materials in the Production of Value-Added Corn Snack Products.

The addition of brewer’s spent grain (BSG), sugar beet pulp (SBP) and apple pomace (AP), on the nutritional properties of directly expanded snack products based on corn grits was investigated. Snack products were produced in a laboratory single screw extruder with the addition of 5, 10 and 15% d. m. of these by-products in corn grits. Chemical composition, total phenolic content, antioxidant activity, dietary fiber, resistant starch, starch damage and pasting properties of the mixtures and extruded samples were determined. Extrusion process and by-product additions had a significant effect on the proximate chemical composition. All three by-products increased contents of both soluble and insoluble dietary fiber, while the extrusion caused a reduction of insoluble fiber and increase of soluble fiber. After the extrusion process starch damage and antioxidant activity increased, while resistant starch content and total polyphenol content decreased. According to obtained results, it can be concluded that the investigated by-products can be used in the production of nutritionally more valuable corn snacks.

Modification of heat-induced whey protein isolate hydrogel with highly bioactive glass particles results in promising biomaterial for bone tissue engineering

This study deals with the design and comprehensive evaluation of novel hydrogels based on whey protein isolate (WPI) for tissue regeneration. So far, WPI has been considered mainly as a food industry by-product and there are very few reports on the application of WPI in tissue engineering (TE). In this work, WPI-based hydrogels were modified with bioactive glass (BG), which is commonly used as a bone substitute material. Ready-to-use, sterile hydrogels were produced by a simple technique, namely heat-induced gelation. Two different concentrations (10 and 20% w/w) of sol–gel-derived BG particles of two different sizes (2.5 and <45 µm) were compared. µCT analysis showed that hydrogels were highly porous with almost 100% pore interconnectivity. BG particles were generally homogenously distributed in the hydrogel matrix, affecting pore size, and reducing material porosity. Thermal analysis showed that the presence of BG particles in WPI matrix reduced water content in hydrogels and improved their thermal stability. BG particles decreased enzymatic degradation of the materials. The materials underwent mineralization in simulated biological fluids (PBS and SBF) and possessed high radical scavenging capacity. In vitro tests indicated that hydrogels were cytocompatible and supported MG-63 osteoblastic cell functions.

Valorization of food industry waste and by-products using 3D printing: A study on the development of value-added functional cookies

Wastes and by-products of the food industry are often overlooked and utilized or underutilized. Of late, the emphasis is being given to recover, recycle, and recondition waste, promoting sustainable food processing. In this research, grape pomace and broken wheat which are otherwise sent for animal feed were collected from industries and were used as key ingredients of a 3D printing material supply for the production of functional cookies. The administration of grape pomace augmented the nutritional value and antioxidant properties of the cookies. Printing using a nozzle diameter of 1.28 mm, extruder motor speed of 600 rpm, and print speed of 400 mm/min gave the optimal printability for the in-house developed extrusion-based food 3D printer CARK. The printed constructs were post-processed at 130 °C for 12 min and the 6% grape pomace formulation received the highest preference during sensory evaluation. Interestingly, the developed product was rich in proteins and dietary fiber. This approach highlights the potential for value addition of industrial waste streams with good consumer preference. Accordingly, the unmatched levels of customization that additive manufacturing offers can be well complemented with personalizing foods in terms of nutritional content, whilst providing scope for cleaner production practices and improved recovery of resources from food processing wastes.

Protocol for Designing New Functional Food with the Addition of Food Industry By-Products, Using Design Thinking Techniques-A Case Study of a Snack with Antioxidant Properties for Physically Active People.

The aim of the work was to develop an easy-to-follow protocol for designing novel functional products with the addition of food industry by-products using design thinking techniques. As a result, a 12-step protocol has been designed and presented. The protocol consists of steps from the initial formation of the design team, through all the stages of the production and prototyping, until establishing the final storage conditions and creating final documentation. The protocol has been validated and explained using a case study in which a fish industry by-product hydrolysate with bioactive properties was used to develop a novel functional food product for physically active people: a date bar with carp meat and carp skin gelatin hydrolysate. Following the 12 steps presented in the protocol resulted in developing a food product with high nutritional value and antioxidant power which remains stable during storage at reduced temperatures. Moreover, the product is characterized by good sensory qualities and can be easily implemented into full-scale production. The newly designed protocol is an easy-to-follow method that could be used in almost any kind of food industry sector to sucesfully develop user-focused functional food products with by-product addition.

By-Products from Food Industry as a Promising Alternative for the Conventional Fillers for Wood-Polymer Composites.

The present paper describes the application of two types of food-industry by-products, brewers’ spent grain (BSG), and coffee silverskin (ŁK) as promising alternatives for the conventional beech wood flour (WF) for wood–polymer composites. The main goal was to investigate the impact of partial and complete WF substitution by BSG and ŁK on the processing, structure, physicochemical, mechanical, and thermal properties of resulting composites. Such modifications enabled significant enhancement of the melt flowability, which could noticeably increase the processing throughput. Replacement of WF with BSG and ŁK improved the ductility of composites, which affected their strength however. Such an effect was attributed to the differences in chemical composition of fillers, particularly the presence of proteins and lipids, which acted as plasticizers. Composites containing food-industry by-products were also characterized by the lower thermal stability compared to conventional WF. Nevertheless, the onset of decomposition exceeding 215 °C guarantees a safe processing window for polyethylene-based materials.

Antioxidant and Antiglycation Effects of Polyphenol Compounds Extracted from Hazelnut Skin on Advanced Glycation End-Products (AGEs) Formation.

The advanced glycation end-products (AGEs) arise from non-enzymatic reactions of sugar with protein side chains, some of which are oxido-reductive in nature. Enhanced production of AGEs plays an important role in the pathogenesis of diabetic complications as well as in natural aging, renal failure, oxidative stress, and chronic inflammation. The aim of this work is to study antiglycation effects of polyphenol compounds extracted by hazelnut skin that represents an example of polyphenols-rich food industry by-product, on AGEs formation. AGEs derived from incubation of bovine serum albumin (BSA) and methylglyoxal (MGO) were characterized by fluorescence. The phenolics identification and total polyphenol content in hazelnut skin extracts were analyzed by HPLC-MS and the Folin–Ciocalteu method, respectively. Antioxidant efficacy was evaluated by monitoring total antioxidant activity to assess the ABTS radical scavenging activity of samples by TEAC assay and oxygen radical absorbance capacity (ORAC) assay, expressed as millimoles of Trolox equivalents per gram of sample. Data here presented suggest that phenolic compounds in hazelnut skin have an inhibitory effect on the BSA-AGEs model in vitro, and this effect is concentration-dependent. The putative role of the hazelnut skin antioxidative properties for hindering AGEs formation is also discussed. Because of AGEs contribution to the pathogenesis of several chronic diseases, foods enriched, or supplements containing natural bioactive molecules able to inhibit their production could be an interesting new strategy for supporting therapeutic approaches with a positive effect on human health.

Physical Properties of Chocolates Enriched with Untreated Cocoa Bean Shells and Cocoa Bean Shells Treated with High-Voltage Electrical Discharge

Recently, the enrichment of chocolate has become a very interesting topic, along with the management of food industry by-products, such as cocoa shells. Cocoa shells could be a great raw material for the cocoa industry, both for economical reasons (maximized utilization of cocoa beans) and for their functional properties (increased fiber content). In this research, we used untreated and high-voltage electrical discharge (HVED)-treated cocoa shells in the production of chocolate. Different proportions of cocoa mass were replaced with cocoa shells to produce dark and milk chocolates in a ball mill. Additionally, dark chocolate with 15% and milk chocolate with 5% of shells were chosen for further research and to study the alteration of the composition. The rheology, particle size distribution, hardness, and color were determined for all the prepared samples. Treated cocoa shells provided chocolates with inferior physical properties compared to chocolates with untreated shells. Therefore, untreated cocoa shells were selected for further analysis. The addition of both treated and untreated cocoa shells resulted in softening and darkening of samples, which could have a positive effect for consumers. On the other hand, the particle size distribution and rheology were negatively affected. Further research is needed to find a solution for these problems.

Rainbow Trout (Oncorhynchus mykiss) Skin as Potential n-3 Fatty Acid Source

The rise in the demand and the limited availability of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids claim to obtain these important long chain polyunsaturated fatty acids (LCPUFA) from novel sources. Skin of rainbow trout is a fish industry by-product but still contains valuable LCPUFA amounts with great potential applications in human nutrition and health. This study aimed to explore the nutritional composition of rainbow trout skin for its use as source of n-3 LCPUFA and its composition modification according to fish diet. Rainbow trout were fed three diets including increasing substitution levels of fishmeal with full-fat black soldier fly (Hermetia illucens) larvae meal (0%, 25%, 50% substitution levels) over 98 days. DHA was the major representative of the n-3 LCPUFA in the skin of all dietary groups, being the H25 group the richest in this fatty acid. The present study shows that the skin of rainbow trout can be a promising source of n-3 LCPUFA. Reusing the skin of farmed fish represents a possible way to decrease food industry by-products, to reduce n-3 LCPUFA shortfall and could lead to the development of functional foods and nutritional supplements including n-3 LCPUFA from fish skin.

Artichoke by Products as a Source of Antioxidant and Fiber: How It Can Be Affected by Drying Temperature.

The reuse of food industry by-products constitutes one of the essential pillars of the change from a linear to a circular economic model. Drying is one of the most affordable techniques with which to stabilize by-products, making their subsequent processing possible. However, it can affect material properties. The objective of this study was to assess the effect of the drying temperature on the drying kinetics and final quality of the main artichoke processing by-products, bracts and stems, which have never been studied as independent materials. For this purpose, air drying experiments at different temperatures (40, 60, 80, 100 and 120 °C) were carried out. The alcohol insoluble residue (AIR) and the total phenolic content (TPC), antioxidant capacity (AC) and vitamin C (VC) of the fresh and dried samples were determined. The bracts dried faster than the stems, increasing drying rate with temperature. The two by-products presented relatively large amounts of AIR, the content being higher in bracts, but better functional properties in stems. The TPC, AC and VC values of the dried samples decreased in relation to the fresh samples, with the temperatures of 40 °C (bracts) and 120 °C (stems) being the most adequate for the purposes of preserving these characteristics.

Characterisation of Muffins with Upcycled Sunflower Flour.

There is an increased interest and need to make our economy more circular and our diets healthier and more sustainable. One way to achieve this is to develop upcycled foods that contain food industry by-products in their formulation. In this context, the aim of this study was to develop muffins containing upcycled sunflower flour (a by-product from the sunflower oil industry) and assess the effects of sunflower flour addition on the fibre, protein, amino acid, mineral content, and antioxidant activity measured by a Ferric Reducing Antioxidant Power (FRAP) assay and Photo chemiluminescence (PCL) assay. Results show that the sunflower flour inclusion significantly improved all the parameters analysed as part of this study. A more balanced muffin amino acid profile was achieved, thanks to the increased levels of lysine, threonine, and methionine, the limiting essential amino acids of wheat flour. We can conclude that upcycled ingredients, such as sunflower flour, could be used for the nutritional improvement of baked goods, such as muffins. Their addition can result in several nutritional advantages that could be communicated on packaging through the use of the appropriate EU nutrition claims, such as those on protein, fibre, and mineral content.

Chitosan and Hydroxyapatite Based Biomaterials to Circumvent Periprosthetic Joint Infections.

Every year, worldwide, millions of people suffering from joint pain undergo joint replacement. For most patients, joint arthroplasty reduces pain and improve function, though a small fraction will experience implant failure. One of the main reasons includes prosthetic joint infection (PJI), involving the prosthesis and adjacent tissues. Few microorganisms (MO) are required to inoculate the implant, resulting in the formation of a biofilm on its surface. Standard treatment includes not only removal of the infected prosthesis but also the elimination of necrotic bone fragments, local and/or systemic administration of antibiotics, and revision arthroplasty with a new prosthesis, immediately after the infection is cleared. Therefore, an alternative to the conventional therapeutics would be the incorporation of natural antimicrobial compounds into the prosthesis. Chitosan (Ch) is a potential valuable biomaterial presenting properties such as biocompatibility, biodegradability, low immunogenicity, wound healing ability, antimicrobial activity, and anti-inflammatory potential. Regarding its antimicrobial activity, Gram-negative and Gram-positive bacteria, as well as fungi are highly susceptible to chitosan. Calcium phosphate (CaP)-based materials are commonly utilized in orthopedic and dentistry for their excellent biocompatibility and bioactivity, particularly in the establishment of cohesive bone bonding that yields effective and rapid osteointegration. At present, the majority of CaP-based materials are synthetic, which conducts to the depletion of the natural resources of phosphorous in the future due to the extensive use of phosphate. CaP in the form of hydroxyapatite (HAp) may be extracted from natural sources as fish bones or scales, which are by-products of the fish food industry. Thus, this review aims to enlighten the fundamental characteristics of Ch and HAp biomaterials which makes them attractive to PJI prevention and bone regeneration, summarizing relevant studies with these biomaterials to the field.

Impact of the incorporation of date pit flour an underutilized biowaste in dough and its functional role as a fat replacer in biscuits

Date pit (Phoenix dactylifera L.), an underutilized biowaste, is the major by-product of the date processing industry. Date pits (DPs) are the naturally rich sources of several bioactive compounds that play a vital role in the prevention of the diseases. In the present study, the effect of date pit flour (DPF) as a fat replacer in biscuits at different concentrations (10, 20, 30, and 40% wt/wt) was explored. The proximate, functional, rheological, microstructural, phytochemical, antioxidant, nutritional, and sensory properties of the flour and the biscuits samples were evaluated. The results demonstrated that different ratios of DPF and wheat flour (WF) had high contents of ash, crude fibers, proteins, phytochemicals, and antioxidant activity in contrast to the commercial WF that showed lowest values for all the above components. It was observed that the inclusion of DPF (used in same percentage as fat replacer in biscuit formulation) in the WF alters dough rheology significantly. The gluten content of the flour blends decreased with the addition of DPF while the water absorption increased that interfere in the gluten development time, and it was increased from 1.67 min for control (without DPF) to 7 min for 40% DPF substitution. The scanning electron microscopy of biscuits dough elaborated after fat replacement at different levels showing that evenly distribution of starch granule was disrupted, and the gluten matrix was often ruptured. The total phenolic content (TPC) and total flavonoid content (TFC) increased from 18.56 to 451.60 mg GAE/100 gm of sample and 27.43 to 361.20 mg CE/100 g, respectively. Although, baking decreased the TPC, whereas TFC was increased as compared to the control, and similar results were observed for the antioxidant activity for other substituted biscuits. The crude fiber and protein contents of DPF-WF biscuits were improved from 0.44% to 8.70% and 11.79 to 12.69%, respectively, Sensory and textural performance exhibited that the biscuits were acceptable after fat replacement up to 20% DPF. Based on this study, DPF may be suggested as an excellent natural fat replacer to be used in nutraceuticals and functional foods. Practical applications The current approach enhances the economy of date processing industries by providing value to waste as date pits (DPs). Furthermore, it may be suggested that date pit flour (DPF) is a valuable food industry waste that may play highly beneficial role in producing bakery products of enhanced nutritional values at economical cost. The study had shown that certain compounds of DPF such as proteins, fibers, and phytochemicals which apart from being active and important nutrients may contribute to desirable functional properties by closed interactions at the molecular level between the components of major ingredients. The mixing process provides opportunities to form complexes from these interactions that further react during baking when a suitable thermal atmosphere is available. It seems that introducing DPF is a good discovery that has opened the wide door for numerous novel nutraceutical product development and simultaneously making use of food industry by-products.

Design and validation of a nutritional recipe for a snack made of green banana peel flour (Musa paradisiaca)

Abstract This study aims to design and validate a nutritional recipe for a snack made of Green Banana (Musa paradisiaca) Peel Flour (GBPF) and to assess the nutritional composition and microbiological quality of the flour. Banana peel, a food industry by-product, is a nutritious, low-cost material available for all year. Banana peel flower could be used as a functional ingredient due to its high fiber content and good functional properties. In general, university students have a deficient dietary fiber intake due to altered dietary patterns; thus, this study was focused on this population. The GBPFs were obtained from the peels of pre-climacteric bananas by fluidized bed (FDB) dryer, after which, microbiological, proximate, and dietary fiber analyses were applied. It was designed the nutritional recipe for the snack taking into account the energy and dietary fiber nutritional requirements of the target population. It could be validated and adjusted the recipe following the methodology of Centro Nacional de Alimentación y Nutrición, concluding with the determination of dietary fiber in the end-product. The dietary fiber, total carbohydrate, protein, total fat and energy contents of the GBPF were as following: 38.7 g, 76.3 g, 5.9 g, 3.6 g, and 361.2 kcal, per 100 g of flour. The snack contained 7.74 g of dietary fiber per serving size, having a good acceptance among the university students' panelists based on an organoleptic test. In conclusion, the GBPF showed great potential as a source of dietary fiber, and it was an excellent source of carbohydrates and other nutrients to a lesser degree. When included as a functional ingredient in the nutritional formulation of a snack, it had an overall positive effect on the product’s organoleptic characteristics.

A sörtörköly, mint söripari melléktermék sütőiparban történő alkalmazása

The utilization of food industry byproducts is one of today’s important environmental and economic tasks. Byproducts that form during food production are typically used for feed purposes, but in many cases these materials can also be used in the production of human foods. The brewer’s spent grain left behind after brewing beer is a byproduct with favorable nutrition parameters, with low sugar and high fiber and protein contents. The main objective of our experiments was the reintroduction of brewer’s spent grain into the food industry, with a focus on innovation and sustainable development, by utilizing it in commercially available bakery products (salty medallions / wafers) formulated and regulated in the Hungarian Food Codex. Brewer’s spent grain consists of vegetable proteins and fibers (inactive malt), which may improve the compositional characteristics when preparing bakery products. In the course of our research, medallions enriched with brewer’s spent grain were prepared, of the beneficial parameters of which its high dietary fiber content should be highlighted, which can contribute to the realization of a health-conscious diet for consumers. A diet rich in dietary fiber, combined with an adequate amount of exercise, can reduce the risk of developing certain diseases (e.g., cancer and cardiovascular diseases).

Food By-Products to Extend Shelf Life: The Case of Cod Sticks Breaded with Dried Olive Paste.

Recently, the interest in recovery bioactive compounds from food industrial by-products is growing abundantly. Olive oil by-products are a source of valuable bioactive compounds with antioxidant and antimicrobial properties. One of the most interesting by-products of olive oil obtained by a two-phase decanter is the olive paste, a wet homogeneous pulp free from residuals of the kernel. To valorize the olive paste, ready-to-cook cod sticks breaded with dried olive oil by-products were developed. Shelf-life tests were carried out on breaded cod sticks and during 15 days of storage at 4 °C pH evolution, microbiological aspects, and sensory properties were also monitored. In addition, the chemical quality of both control and active samples was assessed in terms of total phenols, flavonoids, and antioxidant activity. The enrichment with olive paste increased the total phenols, the flavonoids, and the antioxidant activity of the breaded fish samples compared to the control. Furthermore, the bioactive compounds acted as antimicrobial agents, without compromising the sensory parameters. Therefore, the new products recorded a longer shelf life (12 days) than the control fish sample that remained acceptable for nine days.

Brewer's Spent Grains-Valuable Beer Industry By-Product.

The brewing sector is a significant part of the global food industry. Breweries produce large quantities of wastes, including wastewater and brewer’s spent grains. Currently, upcycling of food industry by-products is one of the principles of the circular economy. The aim of this review is to present possible ways to utilize common solid by-product from the brewing sector. Brewer’s spent grains (BSG) is a good material for sorption and processing into activated carbon. Another way to utilize spent grains is to use them as a fuel in raw form, after hydrothermal carbonization or as a feedstock for anaerobic digestion. The mentioned by-products may also be utilized in animal and human nutrition. Moreover, BSG is a waste rich in various substances that may be extracted for further utilization. It is likely that, in upcoming years, brewer’s spent grains will not be considered as a by-product, but as a desirable raw material for various branches of industry.