Advances on the Valorisation and Functionalization of By-Products and Wastes from Cereal-Based Processing Industry

Cereal processing by-products and wastewater for sustainable protein extraction

The global food supply chain faces significant challenge due to substantial losses and waste, particularly in cereal processing. This review focuses on sustainable protein extraction from wastewater and by-products of key cereals, including rice, wheat, corn, millet, and oats. The structural conformation, molecular weight distribution, amino acid content, and bioactive characteristics of the extracted proteins were examined, highlighting their potential applications in food and allied industries. Certain proteins, such as globulins (52 kDa) and lipid transfer proteins (9 kDa), contribute to the functional qualities of rice by-products, which show strong antioxidant capacity. Zein and gliadins, two proteins found in maize and wheat, have noteworthy bioactive qualities but are linked to issues with allergenicity and high cost associated to their purification and extraction. The protein landscape is further diversified by oats and millet, which have distinct nutritional profiles and compositions. To enhance protein recovery while addressing cost and allergenicity constraints, biorefinery techniques integrating enzyme-assisted extraction with natural deep eutectic solvents (NADES) are explored. These methods not only improve extraction efficiency but also enhance protein bioavailability while reducing dependence on conventional solvents making the process more cost-effective and environmentally sustainable. The integration of these techniques within biorefinery frameworks enables simultaneous recovery of proteins, bioactive compounds, other high-value fractions, while significantly reducing food wastes and supporting circular economy principles. This review highlights the potential of cereal by-products as sustainable protein sources while emphasizing the crucial role of biorefineries in transforming these by-products into high-value products, contributing to a more sustainable and efficient food system.

An updated comprehensive review on waste valorization: Informetric analysis, current insights and future perspectives on cereal waste and byproduct utilization for sustainable industrial applications

Cereal crops have been integral to human sustenance since the Neolithic era which have earned significant attention as staple foods. The year-round cultivation and consumption of cereal-based products have led to the escalating global production of cereals and a rise in industrial processing which results in significant waste generation. These wastes contain high-value nutrients such as carbohydrates, proteins, and lipids. Due to their dense nutritional values, there is a need to link the diverse array of nutrients in major cereal wastes and by-products to their functionalities and relevant industrial applications. This will not only promote sustainable waste management but also economic stability. Existing studies on cereal research were investigated using informetric analysis to provide a quantitative outlook and identify key trends, research priorities, and gaps in cereal studies. Overall, this review presents a comprehensive update on the past, present, and future of sustainable cereal waste valorization, highlighting previous studies and providing insights for future exploration of these biowastes.

Exploring Antimicrobial Compounds from Agri-Food Wastes for Sustainable Applications

Transforming agri-food wastes into valuable products is crucial due to their significant environmental impact, when discarded, including energy consumption, water use, and carbon emissions. This review aims to explore the current research on the recovery of bioactive molecules with antimicrobial properties from agri-food waste and by-products, and discusses future opportunities for promoting a circular economy in its production and processing. Mainly, antibacterial molecules extracted from agri-food wastes are phenolic compounds, essential oils, and saponins. Their extraction and antimicrobial activity against a wide spectrum of bacteria is analyzed in depth. Also, their possible mechanisms of activity are described and classified based on their effect on bacteria, such as the (i) alteration of the cell membrane, (ii) inhibition of energy metabolism and DNA synthesis, and iii) disruption of quorum sensing and biofilm formation. These bioactive molecules have a wide range of possible applications ranging from cosmetics to food packaging. However, despite their potential, the amount of wastes transformed into valuable compounds is very low, due to the high costs relating to their extraction, technical challenges in managing supply chain complexity, limited infrastructure, policy and regulatory barriers, and public perception. For these reasons, further research is needed to develop cost-effective, scalable technologies for biomass valorization.

Unexplored Opportunities of Utilizing Food Waste in Food Product Development for Cardiovascular Health

PURPOSE OF REVIEW

Global food production leads to substantial amounts of agricultural and food waste that contribute to climate change and hinder international efforts to end food insecurity and poverty. Food waste is a rich source of vitamins, minerals, fibers, phenolic compounds, lipids, and bioactive peptides. These compounds can be used to create food products that help reduce heart disease risk and promote sustainability. This review examines the potential cardiovascular benefits of nutrients found in different food waste categories (such as fruits and vegetables, cereal, dairy, meat and poultry, and seafood), focusing on animal and clinical evidence, and giving examples of functional food products in each category.

RECENT FINDINGS

Current evidence suggests that consuming fruit and vegetable pomace, cereal bran, and whey protein may lower the risk of cardiovascular disease, particularly in individuals who are at risk. This is due to improved lipid profile, reduced blood pressure and increased flow-mediated dilation, enhanced glucose and insulin regulation, decreased inflammation, as well as reduced platelet aggregation and improved endothelial function. However, the intervention studies are limited, including a low number of participants and of short duration. Food waste has great potential to be utilized as cardioprotective products. Longer-term intervention studies are necessary to substantiate the health claims of food by-products. Technological advances are needed to improve the stability and bioavailability of bioactive compounds. Implementing safety assessments and regulatory frameworks for functional food derived from food waste is crucial. This is essential for maximizing the potential of food waste, reducing carbon footprint, and improving human health.

Toxicological analysis of metals content in agro-food wastes as possible supplement in animal feed

The agro-food surplus is considered the most abundant renewable resource, interesting for the economic and environmental impact, with a possible employment in different productive fields such as supplement in animal feed. For a safe and effective enhancement of agro-food wastes it is needed a toxicological analysis before of their employment, to avoid potential risks to animals, humans and environment. The purpose of this study was to evaluate the metals content (Cu, Fe, Zn, Mg, Na, K, Ca, Mn, Se, Zn, Co, Ni, V, Sb, Mo, Cr and Pb, Cd, As, Ba), in agro-food wastes through ICP-MS analysis. The results obtained showed the presence of metals analysed with a significant content of essential micro and macro-elements; with regard to toxic metals, only strawberries and fennel samples showed Pb levels above the MRL. These data confirm, from the toxicological point of view, a possible and safe reuse of the most of all agro-food wastes, as raw material at low cost and rich of essential nutrients and particularly as supplement in animal feed.

Developing multifunctional cellulose derivatives for environmental and biomedical applications: Insights into modification processes and advanced material properties

The growing bioeconomic demand for lightweight, eco-friendly materials with functional versatility and competitive mechanical properties drives the resurgence of cellulose as a sustainable scaffold for various applications. This review comprehensively scrutinizes current progressions in cellulose functional materials (CFMs), concentrating on their structure-property connections. Significant modification methods, including cross-linking, grafting, and oxidation, are discussed together with preparation techniques categorized by cellulose sources. This review article highlights the extensive usage of modified cellulose in various industries, particularly its potential in optical and toughening applications, membrane production, and intelligent bio-based systems. Prominence is located on low-cost procedures for developing biodegradable polymers and the physical-chemical characteristics essential for biomedical applications. Furthermore, the review explores the role of cellulose derivatives in smart packaging films for food quality monitoring and deep probes into cellulose's mechanical, thermal, and structural characteristics. The multifunctional features of cellulose derivatives highlight their worth in evolving environmental and biomedical engineering applications.

Development of edible nanoemulsions containing vitamin E using a low-energy method: Evaluation of particle size and physicochemical properties for food and beverage applications

Pasta, a globally popular dish, serves as a complete meal around the world. This research aims to improve the nutritional value of pasta by enriching it with vitamin E. Firstly, vitamin E and sesame oil were mixed in different ratios (1:10, 1:5, 10:10) and dissolved in an aqueous medium at 50 °C with different concentrations of Tween 80 (10 %, 20 %, 30 %). Coarse emulsions were formed by gradual addition of the oil phase to the aqueous phase, followed by equilibration using an Ultratrax mixer at 15,000 rpm for 5 min. The target nanoemulsions were then produced using an ultrasonic system. After 30 days of storage, the most stable nanoemulsions containing 10 % Tween 80 and a 1:10 ratio of vitamin E to sesame oil showed minimal changes. In addition, nanoemulsions with 10 % Tween 80 and a 10:10 ratio of vitamin E to sesame oil showed less turbidity than those with 20 % and 30 % Tween 80. Evaluation of enriched pasta for physical, chemical and sensory properties compared to non-enriched samples showed no significant differences in properties such as pH, ash, total solids, texture and colour characteristics (P < 0.05). Enriched pasta samples showed an increase in moisture content of 0.94 % and a decrease in weight loss of 2.13 % compared to the control, with improved brightness (L) and yellowness (b) due to the addition of nanoemulsion. Sensory evaluation showed higher scores for pasta samples enriched with nanoemulsions containing vitamin E compared to control samples. This pioneering study introduces nanoemulsion technology to improve the nutritional profile of pasta by enriching it with vitamin E. The research demonstrates the successful formulation of stable nanoemulsions and their positive effects on pasta properties, suggesting promising avenues for improving public health through innovative pasta enrichment methods.

Valorization of Grain and Oil By-Products with Special Focus on Hemicellulose Modification

Hemicellulose is one of the most important natural polysaccharides in nature. Hemicellulose from different sources varies in chemical composition and structure, which in turn affects the modification effects and industrial applications. Grain and oil by-products (GOBPs) are important raw materials for hemicellulose. This article reviews the modification methods of hemicellulose in GOBPs. The effects of chemical and physical modification methods on the properties of GOBP hemicellulose biomaterials are evaluated. The potential applications of modified GOBP hemicellulose are discussed, including its use in film production, hydrogel formation, three-dimensional (3D) printing materials, and adsorbents for environmental remediation. The limitations and future recommendations are also proposed to provide theoretical foundations and technical support for the efficient utilization of these by-products.

Recent advances and insights into the bioactive properties and applications of Rosa canina L. and its by-products

Rosa canina L., commonly known as rosehip, is of notable scientific interest for its applications in nutrition, cosmetics, and pharmaceuticals. This review article highlights its health-promoting properties, including antioxidant, anti-inflammatory, hepatoprotective, and anticarcinogenic effects, attributed to its rich content of phenolic acids, carotenoids, tocopherols, and vitamins. With growing interest in sustainable practices, rosehip by-products are increasingly valorized. For instance, cold-pressed rosehip seed oil is a valuable source of polyunsaturated fatty acids, while incorporating rosehip pomace into snacks enhances their nutritional profile, positioning them as potential functional foods and dietary supplements. This article aims to provide a comprehensive overview of advancements in utilizing rosehip and its by-products, emphasizing their role in enriching food and pharmaceutical products with nutritional and functional bioactivities.

Insights into Grain Milling and Fractionation Practices for Improved Food Sustainability with Emphasis on Wheat and Peas

Cereal grains and pulses are staple foods worldwide, being the primary supply of energy, protein, and fiber in human diets. The current practice of milling and fractionation yields large quantities of byproducts and waste, which are largely downgraded and end up as animal feeds or fertilizers. This adversely affects food security and the environment, and definitely implies an urgent need for a sustainable grain processing system to rectify the current issues, particularly the management of waste and excessive use of water and energy. The current review intends to discuss the limitations and flaws of the existing practice of grain milling and fractionation, along with potential solutions to make it more sustainable, with an emphasis on wheat and peas as common fractionation crops. This review discusses a proposed sustainable grain processing system for the fractionation of wheat or peas into flour, protein, starch, and value-added components. The proposed system is a hybrid model that combines dry and wet fractionation processes in conjunction with the implementation of three principles, namely, integration, recycling, and upcycling, to improve component separation efficiency and value addition and minimize grain milling waste. The three principles are critical in making grain processing more efficient in terms of the management of waste and resources. Overall, this review provides potential solutions for how to make the grain processing system more sustainable.

Trends in extracting Agro-byproducts' phenolics using non-thermal technologies and their combinative effect: Mechanisms, potentials, drawbacks, and safety evaluation

The agro-food industries generate significant waste with adverse effects. However, these byproducts are rich in polyphenols with diverse bioactivities. Innovative non-thermal extraction (NTE) technologies (Naviglio extractor®, cold plasma (CP), high hydrostatic pressure (HHP), pulse-electric field (PEF), ultrasound-assisted extraction (UAE), etc.) and their combinative effect (integrated UAE + HPPE, integrated PEF + enzyme-assisted extraction, etc.) could improve polyphenolic extraction. Hence, this article comprehensively reviewed the mechanisms, applications, drawbacks, and safety assessment of emerging NTE technologies and their combinative effects in the last 5 years, emphasizing their efficacy in improving agro-byproduct polyphenols' extraction. According to the review, incorporating cutting-edge NTE might promote the extraction ofmore phenolic extractfrom agro-byproducts due to numerous benefits,such as increased extractability,preserved thermo-sensitive phenolics, and low energy consumption. The next five years should investigate combined novel NTE technologies as they increase extractability. Besides, more research must be done on extracting free and bound phenolics, phenolic acids, flavonoids, and lignans from agro by-products. Finally, the safety of the extraction technology on the polyphenolic extract needs a lot of studies (in vivo and in vitro), and their mechanisms need to be explored.

Rice Byproduct Compounds: From Green Extraction to Antioxidant Properties

Currently, rice (Oryza sativa L.) production and consumption is increasing worldwide, and many efforts to decrease the substantial impact of its byproducts are needed. In recent years, the interest in utilizing rice kernels, husk, bran, and germ for the recovery of different molecules, from catalysts (to produce biodiesel) to bioactive compounds, has grown. In fact, rice byproducts are rich in secondary metabolites (phenolic compounds, flavonoids, and tocopherols) with different types of bioactivity, mainly antioxidant, antimicrobial, antidiabetic, and anti-inflammatory, which make them useful as functional ingredients. In this review, we focus our attention on the recovery of antioxidant compounds from rice byproducts by using innovative green techniques that can overcome the limitations of traditional extraction processes, such as their environmental and economic impact. In addition, traditional assays and more innovative methodologies to evaluate the antioxidant activity are discussed. Finally, the possible molecular mechanisms of action of the rice byproduct antioxidant compounds (phenolic acids, flavonoids, γ-oryzanol, and vitamin E) are discussed as well. In the future, it is expected that rice byproduct antioxidants will be important food ingredients that reduce the risk of the development of several human disorders involving oxidative stress, such as metabolic diseases, inflammatory disorders, and cancer.

Overview of the Sustainable Valorization of Using Waste and By-Products in Grain Processing

In an increasingly resource-constrained era, using waste and by-products from grain processing has a wide appeal. This is due to the nutritive value and economic aspects of this process and due to its compatibility with the trend towards more sustainable food systems. Following the fundamentals of circular economy, a current need is the effective utilization of grain waste and by-products for conversion into value-added products in the food industry. The aim of this study is twofold: (1) using bibliometrics and the literature found in various databases, we aim to understand the progress of valorizing grain waste and by-products in human nutrition. The literature within various databases, namely, Google Scholar, Web of Science, and Elsevier Scopus, has been evaluated for its merits and values. (2) We aim to explore knowledge-based strategies by reviewing the literature concerning the possible use of grain waste and by-products for the food processing industry, reducing the burden on virgin raw materials. The review allowed us to unlock the latest advances in upcycling side streams and waste from the grain processing industry.

Cereal bran proteins: recent advances in extraction, properties, and applications

The projected global population is expected to reach around 9.7 billion by 2050, indicating a greater demand for proteins in the human diet. Cereal bran proteins (CBPs) have been identified as high-quality proteins, with potential applications in both the food and pharmaceutical industries. In 2020, global cereal grain production was 2.1 billion metric tonnes, including wheat, rice, corn, millet, barley, and oats. Cereal bran, obtained through milling, made up 10-20% of total cereal grain production, varying by grain type and milling degree. In this article, the molecular composition and nutritional value of CBPs are summarized, and recent advances in their extraction and purification are discussed. The functional properties of CBPs are then reviewed, including their solubility, binding, emulsifying, foaming, gelling, and thermal properties. Finally, current challenges to the application of CBPs in foods are highlighted, such as the presence of antinutritional factors, low digestibility, and allergenicity, as well as potential strategies to improve the nutritional and functional properties by overcoming these challenges. CBPs exhibit nutritional and functional attributes that are similar to those of other widely used plant-based protein sources. Thus, CBPs have considerable potential for use as ingredients in food, pharmaceutical, and other products.

Ultrasound-assisted extraction and characteristics of maize polysaccharides from different sites

Antitumor, antioxidant, hypoglycemic, and immunomodulatory properties are all exhibited by maize polysaccharides. With the increasing sophistication of maize polysaccharide extraction methods, enzymatic method is no longer limited to a single enzyme to extract polysaccharides, and is more often used in combination with ultrasound or microwave, or combination with different enzymes. Ultrasound has a good cell wall-breaking effect, making it easier to dislodge lignin and hemicellulose from the cellulose surface of the maize husk. The "water extraction and alcohol precipitation" method is the simplest but most resource- and time-consuming process. However, the "ultrasound-assisted extraction" and "microwave-assisted extraction" methods not only compensate for the shortcoming, but also increase the extraction rate. Herein, the preparation, structural analysis, and activities of maize polysaccharides were analyzed and discussed.

Valorization of wastes and by-products of nuts, seeds, cereals and legumes processing

Wastes and by-products of nuts, seeds, cereals and legumes carry a unique potential for valorization into value-added ingredients due to their protein, dietary fiber, antioxidant, vitamin and mineral contents. The most crucial factor in the recovery of value-added ingredients and bioactives from the wastes and by-products is the utilization of the most efficient extraction technique. This work is an overview of the classification of wastes and by-products of nuts, seeds, cereals and legumes processing, the methods used in the extraction of valuable compounds such as proteins, dietary fibers, phenolics, flavonoids and other bioactives. This chapter provides insights on the promising applications of extracted ingredients in various end products. A special emphasis is given to the challenges and improvement methods for extraction of value-added compounds from wastes and by-products of nuts, seeds, cereals and legumes processing.

Second generation Pichia pastoris strain and bioprocess designs

Yeast was the first microorganism used by mankind for biotransformation processes that laid the foundations of industrial biotechnology. In the last decade, Pichia pastoris has become the leading eukaryotic host organism for bioproduct generation. Most of the P. pastoris bioprocess operations has been relying on toxic methanol and glucose feed. In the actual bioeconomy era, for sustainable value-added bioproduct generation, non-conventional yeast P. pastoris bioprocess operations should be extended to low-cost and renewable substrates for large volume bio-based commodity productions. In this review, we evaluated the potential of P. pastoris for the establishment of circular bioeconomy due to its potential to generate industrially relevant bioproducts from renewable sources and waste streams in a cost-effective and environmentally friendly manner. Furthermore, we discussed challenges with the second generation P. pastoris platforms and propose novel insights for future perspectives. In this regard, potential of low cost substrate candidates, i.e., lignocellulosic biomass components, cereal by-products, sugar industry by-products molasses and sugarcane bagasse, high fructose syrup by-products, biodiesel industry by-product crude glycerol, kitchen waste and other agri-food industry by products were evaluated for P. pastoris cell growth promoting effects and recombinant protein production. Further metabolic pathway engineering of P. pastoris to construct renewable and low cost substrate utilization pathways was discussed. Although, second generation P. pastoris bioprocess operations for valorisation of wastes and by-products still in its infancy, rapidly emerging synthetic biology tools and metabolic engineering of P. pastoris will pave the way for more sustainable environment and bioeconomy. From environmental point of view, second generation bioprocess development is also important for waste recycling otherwise disposal of carbon-rich effluents creates environmental concerns. P. pastoris high tolerance to toxic contaminants found in lignocellulosic biomass hydrolysate and industrial waste effluent crude glycerol provides the yeast with advantages to extend its applications toward second generation P. pastoris strain design and bioprocess engineering, in the years to come.

The Use of Durum Wheat Oil in the Preparation of Focaccia: Effects on the Oxidative Stability and Physical and Sensorial Properties

Durum wheat oil is an innovative oil that could be considered the “second life” of durum wheat milling by-products. In this study, we proposed the use of this oil in the reformulation of a traditional Italian greased flat bread, namely focaccia, whose typical sensorial features are due to the presence of relevant amounts of oil in its formulation. The chemical, physical, and sensorial features of focaccia with durum wheat oil (DWO) were compared with those of focaccia prepared with olive oil (OO) and sunflower oil (SO). The results showed the prevalence of polyunsaturated fatty acids in DWO, followed by SO. DWO was more resistant to oxidation than SO (induction time 86.2 and 66.3 min, respectively), due to its higher content of tocotrienols (1020 and 70.2 mg/kg in DWO and SO, respectively), but was less resistant than OO, richer in monounsaturated fatty acids, and contained phenolic compounds. The volatile oxidation markers, namely hexanal and nonanal, were less prevalent in OO and DWO than in SO. Texture and color were positively influenced by the use of durum wheat oil, allowing the nutritional improvement of this flat bread in a sustainable and circular manner.

An Update Regarding the Bioactive Compound of Cereal By-Products: Health Benefits and Potential Applications

Cereal processing generates around 12.9% of all food waste globally. Wheat bran, wheat germ, rice bran, rice germ, corn germ, corn bran, barley bran, and brewery spent grain are just a few examples of wastes that may be exploited to recover bioactive compounds. As a result, a long-term strategy for developing novel food products and ingredients is encouraged. High-value compounds like proteins, essential amino acids, essential fatty acids, ferulic acid, and other phenols, tocopherols, or β-glucans are found in cereal by-products. This review aims to provide a critical and comprehensive overview of current knowledge regarding the bioactive compounds recovered from cereal by-products, emphasizing their functional values and potential human health benefits.

Cereal Waste Valorization through Conventional and Current Extraction Techniques-An Up-to-Date Overview

Nowadays, in the European Union more than 100 million tons of food are wasted, meanwhile, millions of people are starving. Food waste represents a serious and ever-growing issue which has gained researchers’ attention due to its economic, environmental, social, and ethical implications. The Sustainable Development Goal has as its main objective the reduction of food waste through several approaches such as the re-use of agro-industrial by-products and their exploitation through complete valorization of their bioactive compounds. The extraction of the bioactive compounds through conventional methods has been used for a long time, whilst the increasing demand and evolution for using more sustainable extraction techniques has led to the development of new, ecologically friendly, and high-efficiency technologies. Enzymatic and ultrasound-assisted extractions, microwave-assisted extraction, membrane fractionation, and pressure-based extraction techniques (supercritical fluid extraction, subcritical water extraction, and steam explosion) are the main debated green technologies in the present paper. This review aims to provide a critical and comprehensive overview of the well-known conventional extraction methods and the advanced novel treatments and extraction techniques applied to release the bioactive compounds from cereal waste and by-products.

Effects of Teff-Based Sourdoughs on Dough Rheology and Gluten-Free Bread Quality

Production of gluten-free bread (GFB) with good quality characteristics represents a technological challenge. Our study aimed to obtain nongluten bread from cereals and pseudocereals with applying single cultures of Pediococcus acidilactici, Pediococcus pentosaceus and Enteroccocus durans as sourdoughs. The effect of sourdoughs on the quality traits of gluten-free (GF) dough and GFB was explored. The structural and baking properties of GF dough composed of teff, rice, corn, and sorghum flours were improved by adding xanthan gum (0.6%), guar gum (1.0%) and carboxymethyl cellulose (1.0%). The tested strains reached 10⁸ cfu/g in teff flour and produced sourdoughs with a pleasant lactic aroma. The sourdough-fermented doughs were softer and more elastic compared to control dough and yielded reduced baking loss. Strain Enterococcus durans ensured the best baking characteristics of GF dough and the highest softness of the GFB during storage. Strain Pediococcus pentosaceus had the most pronounced positive effect on aroma, taste and aftertaste. Pan baking was found to be more appropriate to obtain stable shape and good-looking products. A careful starter culture selection is necessary for GFB development since a significant effect of strain specificity on dough rheology and baking characteristics was observed.

Sustainable Applications for the Valorization of Cereal Processing By-Products

This review article revises the sustainable practices and applications to valorize valuable components recovered from cereal processing by-products. After introducing cereal processing by-products, their healthy compounds, and corresponding functional properties, the article explores reutilization opportunities of by-products emphasizing specific sources (e.g., oat and wheat bran, distillers' dried grains, etc.) and the biorefinery approach. Proteins and soluble dietary fibers such as arabinoxylans are of particular interest due to their content in the cereal processing by-products and their easy extraction based on conventional technologies such as enzyme-assisted extraction and membrane filtration. Non-thermal technologies have also been suggested to improve sustainability recovery approaches. Finally, the article discusses the different applications for the recovered high-added value compounds that span across biotechnology, foods, and bakery products.

Valorization of cereal by-product hemicelluloses: Fractionation and purity considerations

The biomass from cereal side streams is rich in valuable components, such as hemicelluloses. Among the hemicelluloses, arabinoxylans and β-glucans are the most acknowledged for potential health benefits. Numerous publications discuss the potential to use purified forms of these hemicelluloses for various applications. However, as the purification of hemicelluloses may not be economically feasible to upscale, sustainable and cost-effective methods are needed to make their valorization more realistic for industrial applications. Co-components present in hemicellulose-rich fractions may also provide added functionality, such as flavonoid content and antioxidant capacity. This review provides an overview on the feasibility of sustainably upscaling hemicellulose extraction processes, focusing on by-products from different cereal streams. We describe the hemicelluloses' physicochemical properties and provide various possible applications of pure and impure fractions from small scale to pilot and industrial scale. Furthermore, real case examples on the industrial utilization of cereal side streams are enclosed. This review provides pathways for future research for developing the hemicellulose extraction methods to obtain fractions with optimized purity, and offers suggestions to valorize them.

Microalgal transformation of food processing byproducts into functional food ingredients

Large amounts of food processing byproducts (FPBs) are generated from food manufacturing industries, the second-largest portion of food waste generation. FPBs may require additional cost for post-treatment otherwise cause environmental contamination. Valorization of FPBs into food ingredients by microalgae cultivation can save a high cost for organic carbon sources and nutrients from medium cost. This study reviews FPBs generation categorized by industry and traditional disposal. In contrast with the low-value production, FPBs utilization as the nutrient-abundant medium for microalgae can lead to high-value production. Due to the complex composition in FPBs, various pretreatment methods have been applied to extract the desired compounds and medium preparation. Using the FPB-based medium resulted in cost reduction and a productivity enhancement in previous literature. Although there are still challenges to overcome to achieve economic viability and environmental sustainability, the microalgal transformation of FPBs is attractive for functional food ingredients production.

Bioactive films based on barley β-glucans and ZnO for wound healing applications

In this study, mixtures based on β-glucans and proteins are extracted from barley, in mild (MA) and high (HA) alkaline conditions, and employed with zinc oxide (ZnO) to prepare bioactive films for wound healing. Composition of extracts and properties of resulting films depend on pH extraction conditions. MA based samples show weak physical interactions among mixture components, whereas in HA films the extent of these interactions is larger. Consequently, their chemico-physical properties are significantly different, as demonstrated by FT-IR, thermal, mechanical and morphological analyses. ZnO with its bound water molecules acts as a slight plasticizer in MA, as shown by the lower T_g and the decrease of elastic modulus. In HA, this effect is evidenced up to ZnO 1%, and above this concentration an increase of strength at break is observed. Finally, MA and HA films show intrinsic antimicrobial properties, enhanced by ZnO, which make them exploitable as wound dressings.

Cereal Processing By-Products as Rich Sources of Phenolic Compounds and Their Potential Bioactivities

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.

Statistical Approach to Potentially Enhance the Postbiotication of Gluten-Free Sourdough

Fermented products are permanently under the attention of scientists and consumers, both due to nutritional importance and health promoting effects. The fermented functional foods contribute to a more balanced diet and increase the immune responses (among many other health effects) with positive implications for quality of life. In this sense, improving the sourdough’s fermentation to boost the biotic (postbiotic and paraprobiotic) properties of the sourdough-based products has positive impacts on the nutritional and functional properties of the final baked products. These enhanced sourdoughs can be obtained in controlled fermentation conditions and used as sourdough bread improvers or novel bioingredients. In this context, our work aimed to optimize, using statistical tools, a gluten-free sourdough based on chickpea, quinoa, and buckwheat fermentation with selected lactic acid bacteria (LAB) to enhance its postbiotic properties. The most important biotechnological parameters were selected by Plackett–Burman Design (PBD) and then Response Surface Methodology (RSM) was applied to evaluate the interactions between the selected factors to maximize the gluten-free sourdough’s properties. As a result, the optimized fermented sourdough had antimicrobial activity with inhibition ratios between 71 and 100% against the Aspergillus niger, Aspergillus flavus, Penicillium spp. molds and against the Bacillus spp endospore-forming Gram-positive rods. The optimized variant showed a total titratable acidity (TTA) of 40.2 mL NaOH 0.1N. Finally, the high-performance liquid chromatography (HPLC) analysis highlighted a heterofermentative profile for the organic acids from the optimized sourdough. Among flavonoids and polyphenols, the level of caffeic and vanillic acids increased after lactic acid fermentation. The comparison between the optimized sourdough and the control evidenced significant differences in the metabolite profiles, thus highlighting its potential postbiotication effect.

Monitoring and Optimization of Cupuaçu Seed Fermentation, Drying and Storage Processes

Cupuaçu [Theobroma grandiflorum (Wild ex Spreng.) K. Schum] seeds have been employed for a long time in the Amazon region for food purposes. Similar to cocoa, processed cupuaçu pulp and seeds can be used to produce juices, ice creams, confectionary products and cupulate®, which is a similar product to chocolate. However, its market penetration requires the mastery of all processing stages to improve the food quality and safety and to make possible an efficient technology transfer to the local small farmers and communities. Based on the above, the current research work aimed at monitoring and optimizing the consecutive fermentation and drying processes of cupuaçu seeds over 7 days each, as well as storage for 90 days. A greenhouse structure incorporating the fermenter and solar drying terrace was designed to be inexpensive, versatile, easily scalable, and easy to maintain and operate by the local small farmers after a short period of training. This research effort also aimed at giving a vision for the future creation of an integrative and sustainable cupuaçu system covering the economic, social, cultural and environmental vectors. The experimental design comprised 5 batches of 100 kg of seeds each. Several microbiological and physicochemical parameters were performed and correlated with processing variables. Microbiological parameters encompassed viable counts of mesophilic microorganisms, coliforms, yeasts, and molds, whereas physicochemical measures included fermentation and drying temperature, pH, acidity, dry matter, ashes, water activity, color, total proteins, lipids and carbohydrates, and energy. The average seed fermentation temperature varied from ca. 28 to 44 °C, reaching the maximum on day 3 and a final value of ca. 31 °C. Regarding solar drying, the average seed temperatures ranged from ca. 24 °C (at the end) to 39 °C on day 3, and an initial value of ca. 29 °C. The average final seed pH value of drying was 5.34 and was kept during storage. During storage, results demonstrated the existence of significant correlations among several experimental parameters under scrutiny. Finally, bean viable counts obtained during storage unfolded acceptable values of total mesophilic bacteria well below the maximum limit. Viable counts of yeast and molds were generally found between 3 and 4 log(CFU/gsample), and total coliforms were also detected, although both were at acceptable levels and well beneath the established maximum limits for food safety.