Emerging opportunities for the effective valorization of wastes and by-products generated during olive oil production process: Non-conventional methods for the recovery of high-added value compounds

BackgroundA large amount of wastes and by-products are generated during olive oil production process. Traditionally, these products have been considered as a problem. However, they constitute a great source of high-added value compounds, which have the potential to be used as food additives and/or nutraceuticals. Therefore, valorization of wastes and by-products from food industry kills two birds with one stone and addresses both the use of waste and by-products and societal health, thus greatly contributing for a sustainable food chain from an environmental and economical point of view.Scope and approachIn the present review, current and new insights in the recovery of high-added value compounds from wastes and by-products generated during olive oil production process will be discussed. Several conventional (solvent, heat, grinding) and non-conventional methodologies (ultrasounds, microwaves, sub- and supercritical fluid extractions, pressurized liquid extraction, pulsed electric fields and high voltage electrical discharges) have been investigated for the recovery of high-added value compounds (polyphenols, fatty acids, coloring pigments (chlorophylls and carotenoids), tocopherols, phytosterols, squalene, volatile and aromatic compounds) from wastes and by-products generated during olive oil production process.Key findings and conclusionsNon-conventional technologies can constitute a promising tool to recover high-added value compounds from olive oil wastes and by-products. However, the content of these valuable compounds can vary greatly depending on the matrix and the efficiency in the recovery of these compounds is highly dependent of the technology used for extraction.     

Food waste as a source of value‐added chemicals and materials: a biorefinery perspective

As the availability of fossil‐based resources declines, there is an impending necessity of finding alternative feedstock able to secure the production of fuels and chemicals. Exploitation of biomass as renewable source of chemicals is an attractive possibility, in particular the one derived from food waste (FW). Every year, large amounts of waste are generated within or at the end of the food supply chain at the consumers use stage and hence its valorisation attracts great attention. FW has proven a valuable feedstock for its exploitation to produce a wide array of intermediates and products with promising applications in industry, owing to their similar performance with respect to established products. These include organic acids and furans (generally used as platform chemicals to further products); polymers like bacterial cellulose, polyhydroxyalkanoates or chitin; biosurfactants; biolubricants; or nanoparticles. This overview covers the latest trends in chemical, enzymatic and biotechnological processes reported in literature on the production of these chemicals and materials, with a focus on the use of FW as raw material.     

Current trends of tropical fruit waste utilization

Recent rapid growth of the world's population has increased food demands. This phenomenon poses a great challenge for food manufacturers in maximizing the existing food or plant resources. Nowadays, the recovery of health benefit bioactive compounds from fruit wastes is a research trend not only to help minimize the waste burden, but also to meet the intensive demand from the public for phenolic compounds which are believed to have protective effects against chronic diseases. This review is focused on polyphenolic compounds recovery from tropical fruit wastes and its current trend of utilization. The tropical fruit wastes include in discussion are durian (Durio zibethinus), mangosteen (Garcinia mangostana L.), rambutan (Nephelium lappaceum), mango (Mangifera indica L.), jackfruit (Artocarpus heterophyllus), papaya (Carica papaya), passion fruit (Passiflora edulis), dragon fruit (Hylocereus spp), and pineapple (Ananas comosus). Highlights of bioactive compounds in different parts of a tropical fruit are targeted primarily for food industries as pragmatic references to create novel innovative health enhancement food products. This information is intended to inspire further research ideas in areas that are still under-explored and for food processing manufacturers who would like to minimize wastes as the norm of present day industry (design) objective.     

生物酶法合成单甘酯的研究进展

生物酶法合成单甘酯具有能耗低、产率高、产品安全性能高、反应时间短和无环境污染问题等优点。本文综述了生物酶法合成单甘酯的方法、反应体系和分离提纯方法,同时也介绍了单甘酯在食品中的应用,特别介绍了具有更好乳化性和抗菌性等特性的高含量不饱和脂肪酸单甘酯在食品中的应用。     

Hornification: Lessons learned from the wood industry for attenuating this phenomenon in plant-based dietary fibers from food wastes

A significant amount of waste is annually generated worldwide by the supply chain of the food industry. Considering the population growth, the environmental concerns, and the economic opportunities, waste recovery is a promising solution to produce valuable and innovative ingredients for food and nonfood industries. Indeed, plant-based wastes are rich in dietary fibers (DF), which have relevant technical functionalities such as water/oil holding capacity, swelling capacity, viscosity, texture, and physiological properties such as antioxidant activity, cholesterol, and glucose adsorption capacities. Different drying technologies could be applied to extend the shelf life of fresh DF. However, inappropriate drying technologies or process conditions could adversely affect the functionalities of DF via the hornification phenomenon. Hornification is related to the formation of irreversible hydrogen bindings, van der Waals interactions, and covalent lactone bridges between cellulose fibrils during drying. This review aims to capitalize on the knowledge developed in the wood industry to tackle the hornification phenomenon occurring in the food industry. The mechanisms and the parameters affecting hornification as well as the mitigation strategies used in the wood industry that could be successfully applied to foods are summarized. The application of conventional drying technologies such as air or spray-drying increased the occurrence of hornification. In contrast, solvent exchange, supercritical drying, freeze-drying, and spray-freeze-drying approaches were considered effective strategies to limit the consequences of this phenomenon. In addition, incorporating capping agents before drying attenuated the hornification. The knowledge summarized in this review can be used as a basis for process design in the valorization of plant-based wastes and the production of functional DF that present relevant features for the food and packaging industries.     

Forest biomass waste as a potential innovative source for rearing edible insects for food and feed – A review

Worldwide, huge quantities of organic wastes are generated annually in the forest industry, but most of these wastes are discarded. Only a minor proportion is used, mainly for biofuel and secondarily for compost production. Simultaneously, demand for more and new food products is increasing due to rapid growth in the global population. In recent years, use of edible insects has been proposed as one promising solution to an upcoming food supply crisis. The rearing of insects for human food and livestock feed has some significant advantages, like high protein content, effective feed conversion rate, low greenhouse gas emissions and low water requirements. The aim of this review was to compile up-to-date information on rearing edible insects for food and feed and to investigate the potential use of forest biomass waste as a new substrate for insect rearing.     

Characterization of Bacterial Cellulose by Gluconacetobacter hansenii CGMCC 3917

In this study, comprehensive characterization and drying methods on properties of bacterial cellulose were analyzed. Bacterial cellulose was prepared by Gluconacetobacter hansenii CGMCC 3917, which was mutated by high hydrostatic pressure (HHP) treatment. Bacterial cellulose is mainly comprised of cellulose Iα with high crystallinity and purity. High‐water holding and absorption capacity were examined by reticulated structure. Thermogravimetric analysis showed high thermal stability. High tensile strength and Young's modulus indicated its mechanical properties. The rheological analysis showed that bacterial cellulose had good consistency and viscosity. These results indicated that bacterial cellulose is a potential food additive and also could be used for a food packaging material. The high textural stability during freeze–thaw cycles makes bacterial cellulose an effective additive for frozen food products. In addition, the properties of bacterial cellulose can be affected by drying methods. Our results suggest that the bacterial cellulose produced from HHP‐mutant strain has an effective characterization, which can be used for a wide range of applications in food industry.     

Cello-oligosaccharides production from multi-stage enzymatic hydrolysis by lignocellulosic biomass and evaluation of prebiotic potential

Cello-oligosaccharides (COS) are very recent promising water-soluble dietary fibers, which favors several application in food, chemical and pharmaceutical industries. A three-stage enzymatic hydrolysis of cellulose extracted from agroindustrial wastes (sugarcane straw and coffee husk) with the 1,4-β-endoglucanase cellulase of glycoside hydrolase family (GH12) was developed with a processing time of 48 h. Finds evidenced that removal of products (glucose and cello-oligosaccharides) at each stage provided an increase in cello-oligosaccharides enzymatic hydrolysis in yield of approximately 65%. COS promoted growth of Lactobacillus acidophilus and Lactobacillus brevis after 24 h of fermentation, although they have presented low efficiency with Bifidobacterium sp. This multi-stage enzymatic hydrolysis has potential as a successful strategy to reduction enzyme requirements for COS production with prebiotic properties.Industrial relevanceThis work proposes an innovative technology of multi-stage enzymatic hydrolysis using the enzyme adsorbed on the cellulose surface obtained from renewable sources (sugarcane straw and coffee husk). This strategy is potential to increase the COS yield production and possibly make its cost-viable. The study is also relevant due to accessing the growth promotion of a representative selection of probiotic Lactobacillus and Bifidobacterium strains in order to evidence their prebiotic potential to be used as a possible functional ingredient for the pharmaceutical and food industries.     

Valorization of pomelo (Citrus grandis Osbeck) peel: A review of current utilization,phytochemistry, bioactivities,and mechanisms of action

Citrus grandis Osbeck, commonly known as “pomelo” or “shaddock,” is the largest citrus fruit, the peel of which is a well‐known agricultural residual waste. Pomelo peel offers a wide range of components such as essential oils, polysaccharides, and phytochemicals with potential food applications. Utilization of pomelo peel to recover these components is an important step toward agricultural sustainability. This review covers pomelo peel utilization opportunities beyond conventional composting and animal feed production, and critically examines value‐added uses via the recovery of potentially bioactive components. The peel of pomelo accounts for approximately 30% of the total fruit weight and contains phytochemicals, including aroma‐active volatiles, pectin, flavonoids, phenolic acids, carotenoids, coumarins, and polysaccharides. Recovery of these phytochemicals offers an opportunity for value‐added utilization such as the development of enriched or functional foods and nutraceuticals. The health‐promoting and therapeutic potential of pomelo peel extracts and isolated pure compounds have been evaluated through numerous in vitro and in vivo studies that revealed a wide range of bioactivities, including hypolipidemic, hypoglycemic, antioxidant, antimicrobial, anti‐inflammatory, and anticancer effects. Preclinical evidence highlights multifaceted molecular and signaling events that possibly underlie the said bioactive potential. Overall, the pomelo processing industry offers a great opportunity to recover or produce valuable products from the large amounts of residual wastes it generates. It is envisaged that a thorough understanding of the bioactive components of pomelo peel, their functional and nutraceutical applications, and mode of actions will benefit the food industry.     

Prophylactic components of buckwheat

Buckwheat has been grown for centuries and now it is one of the most important alternative crops and a valuable raw material for functional food production. Many nutraceutical compounds exist in buckwheat seeds and other tissues. It is a rich source of starch and contains many valuable compounds, such as proteins, antioxidative substances, trace elements and dietary fibre. Buckwheat proteins have unique amino acids composition with special biological activities. Besides high-quality proteins, buckwheat seed contain several components with healing benefits: flavonoids and flavones, phytosterols, fagopyrins and thiamin-binding proteins. The allergenic proteins and their derivatives are also present in the buckwheat seeds. For the food industry, the most attractive trend is development of new functional foods, but production of health benefit products has also perspective. In this review we focus on knowledge of protein composition and the other prophylactic compounds of buckwheat products.     

Applications of Wine Pomace in the Food Industry: Approaches and Functions

Winemaking generates large amounts of wine pomace, also called grape pomace. This by‐product has attracted the attention of food scientists and the food industry, due to its high content in nutrients and bioactive compounds. This review mainly focuses on the different published approaches to the use of wine pomace and its functions in the food industry. Traditionally, wine pomace has been used to obtain wine alcohol, food colorings, and grape seed oil. More recently, research has focused in the production of other value‐added products, such as extracts of bioactive compounds, mainly phenols, recovery of tartaric acid, and the making of flours. The most common functions associated with wine pomace products are their use as antioxidants, followed by their use as fortifying, coloring, and antimicrobial agents. These products have mainly been applied to the preparation of meat and fish products and to, a lesser extent, cereal products.     

从皮革废弃物中提取胶原蛋白及其在食品中的应用

本文介绍了采用碱法、酸法、酶法、碱-酶结合法等从皮革工业废弃物中提取胶原蛋白的几种方法，介绍了这些胶原蛋白在食品工业中的应用现状并展望了其应用前最。     

Integrated processing of plant-derived waste to produce value-added products based on the biorefinery concept

BackgroundPlant-derived wastes from agriculture, processing, distribution, and retail are generated in large quantities. The majority of the wastes are underutilized and may cause severe environmental problems if not properly handled. The plant-derived wastes are usually rich in lignocellulose and other valuable compounds including protein, fat, sugar, and phytochemicals. Valorization of these compounds in food waste not only reduces environmental concerns but also improves sustainability and economic competitiveness of agro-food industries.Scope and approachThis review paper first discussed different phases of the biorefinery concepts and their associated applications, and then introduced recent advances in the integrated processing of plant-derived waste for producing various value-added products. Finally, techno-economic, environmental, and social assessments along with relevant policies were introduced and discussed.Key findings and conclusionsDuring the past ten years, research attentions focused on integrated utilization of plant-derived waste to produce various products have flourished. Compared to production of a single component for food waste valorization, integrated processing of food waste via a combination of different novel technologies to produce multiple products based on a biorefinery concept has significant advantages, including full utilization of feedstocks, minimization of waste generation during processing, synergy effects of different technologies, and diversification of the revenues by covering multiple markets. With the rationale design of biorefinery processes, underutilized plant-based wastes can be valuable resources for the sustainable production of food, chemicals, and biofuels. However, detailed economic, environmental, and social analyses for the biorefinery process are still needed in the future.     

Extrusion processing of raw food materials and by-products: A review

ABSTRACT

Extrusion technology has rapidly transformed the food industry with its numerous advantages over other processing methods. It offers a platform for processing different products from various food groups by modifying minor or major ingredients and processing conditions. Although cereals occupy a large portion of the extruded foods market, several other types of raw materials have been used. Extrusion processing of various food groups, including cereals and pseudo cereals, roots and tubers, pulses and oilseeds, fruits and vegetables, and animal products, as well as structural and nutritional changes in these food matrices are reviewed. Value addition by extrusion to food processing wastes and by-products from fruits and vegetables, dairy, meat and seafood, cereals and residues from starch, syrup and alcohol production, and oilseed processing are also discussed. Extrusion presents an economical technology for incorporating food processing residues and by-products back into the food stream. In contemporary scenarios, rising demand for extruded products with functional ingredients, attributed to evolving lifestyles and preferences, have led to innovations in the form, texture, color and content of extruded products. Information presented in this review would be of importance to processors and researchers as they seek to enhance nutritional quality and delivery of extruded products.     

MARINE FISH DIGESTIVE PROTEASES—RELEVANCE TO FOOD INDUSTRY AND THE SOUTH-WEST ATLANTIC REGION—A REVIEW

The biological diversity of marine species provides a wide array of enzymes with unique properties. For this reason, there is great potential for the recovery and use of digestive proteases from fish provessing wastes. Fish digestive proteolytic enzymes most commonly studied include pepsin, trypsin, chymotrypsin, gastricsin and elastase. Enzymes from cold adapted ectothermic organisms have application in the food industry because their temperature and other characteristics differ from homologous proteases from warm-blooded animals. The South-West Atlantic ocean is an enormous reservoir of different fish species. The digestive proteases from these organisms can be isolated as a by-product and used for processing aids in the food industry.     

Application of extrusion technology in plant food processing byproducts: An overview

The food processing industry generates an immense amount of waste, which leads to major concerns for its environmental impact. However, most of these wastes, such as plant‐derived byproducts, are still nutritionally adequate for use in food manufacturing. Extrusion is one of the most versatile and commercially successful processing technologies, with its widespread applications in the production of pasta, snacks, crackers, and meat analogues. It allows a high degree of user control over the processing parameters that significantly alters the quality of final products. This review features the past research on manufacture of extruded foods with integration of various plant food processing byproducts. The impact of extrusion parameters and adding various byproducts on the nutritional, physicochemical, sensory, and microbiological properties of food products are comprehensively discussed. This paper also provides fundamental knowledge and practical techniques for food manufacturers and researchers on the extrusion processing of plant food byproducts, which may increase economical return to the industry and reduce the environmental impact.     

Advances in pullulan production from agro-based wastes by Aureobasidium pullulans and its applications

Pullulan is an important exopolysaccharide commercially obtained from ubiquitous fungi Aureobasidium pullulans. Pullulan has unique physicochemical properties, due to which it has wide applications in the food, pharmaceutical and biomedical industries. Various synthetic media and agro-industrial wastes have been utilized for the production of pullulan. Agro-industrial waste has become a preferred substrate for biotransformation due to its economical aspect and nutritional attributes. Pullulan is one of the valuable products produced by the biotransformation of agro-based wastes. Numerous factors which influence the pullulan production are the type of substrate, the addition of carbon source, nitrogen source, pH of the medium, aeration/ agitation speed and temperature. The cost, productivity of the product and efficiency depends on the selection of raw material, type of fermentation (bioprocess), type of strain and downstream processing (recovery). This review focuses on pullulan production from agro-based wastes, the influence of factors and its applications.     

QUALITY OF FISH SAUCE PRODUCTS FROM RECYCLED BY‐PRODUCTS FROM FISH GEL AND KAMABOKO PROCESSING

ABSTRACT

In order to make effective reuse of kamaboko processing wastes and to minimize the amount of waste disposal, the production of two kinds of fish sauces was tried on a small industrial scale from the wastes with or without the addition of the meat of deepsea smelt (Glossanodon semifasciatus). They were fermented for 6 months at room temperature using salt and koji mold. As a control, a fish sauce was also produced only from the deepsea smelt meat. The recovery of fish sauce from the initial mashed mixture ranged between 75 and 79%, depending on the ingredients in the three fish sauce products. The total nitrogen content of the waste sauce and the mixed sauce was lower than that of the control. The levels of the original additives to kamaboko products, β‐carotene and sorbic acid, were very low in these fish sauces. The taste‐active components of the waste sauce and mixed sauces were lower than those of the control. Sensory evaluation revealed that the former two waste sauces were less bitter and higher in saltiness than the control. However, no difference was found in umami taste between these products. These findings suggest that the wastes from kamaboko processing factories could be reused as fish sauce for food condiments.

PRACTICAL APPLICATIONS

Recent development in the food industry in Japan has enabled the surimi‐based products to be mass produced and standardized even in the fish gel, kamaboko trade. However, a serious problem has arisen in the development of kamaboko processing through the discharge of the wastes, i.e., nonstandard products or fragments, from kamaboko processing factories. It is clear that the waste from kamaboko processing factories is transformed effectively into fish sauce by using soy sauce koji mold. As a result, the amount of the discharged wastes from kamaboko factories are able to be minimized because the liquefaction ratio of the fish sauce mushes (moromi) from the wastes after fermentation was high and the products have a high umami taste and agreeable soy sauce‐like flavor.     

天然食品添加剂—植酸的研制

本文介绍一种用硫酸水溶液自食品工业废弃物中提取植酸的工艺。由于本工艺省掉了阴离子交换工序,使生产投资有所下降。按此工艺可制得纯度高达87.7%,提取率为93.8%的植酸     

食品接触用再生纤维素薄膜的应用进展与法规研究

目的 调研再生纤维薄膜在食品接触材料领域的应用进展,研究食品接触用再生纤维素薄膜的全球立法概况,比较各自优缺点,分析其中可为我国食品接触用再生纤维素薄膜安全管理所用的内容。方法 收集再生纤维素薄膜的行业概况及应用信息,调研再生纤维素薄膜的生产工艺,查询世界各国和地区的相关法律、法规及指令。结果 总结再生纤维薄膜在食品接触材料领域的应用前景,以及世界各国和地区对食品接触用再生纤维素的管理异同点。结论 针对我国再生纤维素的生产和使用现状,参考其他国家和地区的管理经验和管理优势,尽快推动我国食品接触用再生纤维素的产品安全国家标准的制定,以适应行业的发展和合规需要。