Postharvest processes of edible insects in Africa: A review of processing methods,and the implications for nutrition,safety and new products development

In many African cultures, insects are part of the diet of humans and domesticated animals. Compared to conventional food and feed sources, insects have been associated with a low ecological foot print because fewer natural resources are required for their production. To this end, the Food and Agriculture Organization of the United Nations recognized the role that edible insects can play in improving global food and nutrition security; processing technologies, as well as packaging and storage techniques that improve shelf-life were identified as being crucial. However, knowledge of these aspects in light of nutritional value, safety, and functionality is fragmentary and needs to be consolidated. This review attempts to contribute to this effort by evaluating the available evidence on postharvest processes for edible insects in Africa, with the aim of identifying areas that need research impetus. It further draws attention to potential postharvest technology options for overcoming hurdles associated with utilization of insects for food and feed. A greater research thrust is needed in processing and this can build on traditional knowledge. The focus should be to establish optimal techniques that improve presentation, quality and safety of products, and open possibilities to diversify use of edible insects for other benefits.     

Nonthermal technologies affecting techno-functional properties of edible insect-derived proteins,lipids, and chitin: A literature review

To increase the acceptability of edible insects, different strategies have been suggested to dispel neophobia toward this novel food. Extracts of the main nutritional components of insects have been proposed as food ingredients. However, extraction methods can affect the techno-functional properties of insect extracts, especially when heat is applied. Therefore, nonthermal technologies have recently attracted the attention of researchers. Among nonthermal technologies, high hydrostatic pressure (HHP), pulsed electric field (PEF), ultrasound (US) and cold atmospheric plasma (CAPP) have been described and discussed in the current review considering their effect on techno-functional properties of proteins, lipids, and chitin in insect-derived products. HHP and PEF have demonstrated great potential to improve insect protein solubility, whereas the oil holding capacity (OHC) was positively affected by PEF. The water holding capacity (WHC) showed a different performance according to insect species (Gryllodes sigillatus, Acheta domesticus, or Tenebrio molitor) and treatment applied (e.g., HHP). Of note, greater foaming capacity of insect proteins was achieved by applying HHP and US. Regarding insect lipids US assisted extraction with ethanol:water (E:W) extraction, fats rich in unsaturated fatty acids (e.g., linoleic acid) were obtained, whereas, regarding insect chitin, further studies are necessary to clearly understand and improve its extractability.     

Nutritional,functional and biological properties of insect proteins: Processes for obtaining,consumption and future challenges

BackgroundConsuming insects as an alternative protein source is considered a future trend and a viable strategy that could potentially contribute to global food security. Insects are a non-conventional source of protein, either for human consumption directly or indirectly as a component in recomposed foods or added to feedstock mixtures. Moreover, these proteins have demonstrated a broad range of applications as peptides with antihypertensive, antimicrobial and antioxidant properties. However, aspects such as food safety and processing of these proteins need further studies for their elucidation and optimization.Scope and approachIn this review, aspects of nutritional value and risks of insect consumption are reported. Additionally, conventional processing techniques and recent advances in insect protein extraction and production are presented. The application of bioactive peptides obtained from insect protein hydrolysates is reported, focusing on their potential antihypertensive, antimicrobial and antioxidant properties.Key findings and conclusionsInsect proteins have great advantages in terms of nutritional value, total protein level and amino acid profile. However, some safety concerns must be taken into consideration in large-scale production. The conventional processing of insects proteins is very particular, depending on several aspects such as species, larval stage, and cultivation, among others. Nonetheless, recent advances in insect protein production via enzymatic hydrolysis and heterologous expression have shown a promising technology for the study and exploitation of their bioactive properties, such as the antimicrobial, antioxidant and antihypertensive (inhibition of ACE) activity of insect peptides.     

食用昆虫资源的研究与开发进展

从食用昆虫的历史、食用昆虫的营养价值、保健功能和食用昆虫的产业化等方面介绍了食用昆虫资源开发的研究进展.目前,食用昆虫研发方面仍存在食用昆虫的营养成分分析不够透彻、开发投资力度不够、人们对昆虫的营养保健功能认识不足等主要问题.针对上述问题本文提出了几条解决对策：对食用昆虫营养保健作用加大宣传力度,以药用昆虫产业带动食用昆虫产业发展,大力开发昆虫保健食品,建议政府部门加大对食用昆虫开发的投资力度.     

Eat or not eat: an analysis of the status of entomophagy in Botswana

In Botswana, mopane worm Imbrasia belina Westwood is culturally accepted as food by people of different age groups from different regions and districts. However, there are several other insect that are anecdotally known to be edible in Botswana. To verify this, a study was conducted by means of a questionnaire and discussions among Batswana of different age groups from six districts in the country to obtain the names of insects that are known to be edible. A total of 27 insect species was identified. The study also investigated methods of collection, processing, precooking preparation, cooking methods, storage and recipes. Chi-square analysis showed that people’s knowledge of edible insects differed with districts and age groups. Older people were more familiar with uncommon edible insect compared to the younger generation. With the exception of mopane worm, the majority of the people interviewed, especially the young, had not eaten any of the species, despite knowing that they were edible. This shows that, apart from the use of mopane worm, entomophagy (the eating of insect by humans) as practiced among Batswana is declining. However, in the light of current decline in food production in Africa, especially in the arid regions of Botswana, insects may make a valuable contribution to the protein and calories of many peoples’ diets. A shift from traditional harvesting to mass production of insects has the potential to provide animal protein to humans through direct consumption or indirectly when used as livestock feed, and could reduce malnutrition.     

Traditional consumption of and rearing edible insects in Africa,Asia and Europe

ABSTRACT

The traditional consumption of edible insects is common in one third of the world's population, mostly in Latin America, Africa and Asia. There are over one thousand identified species of insects eaten in some stage of their life cycle; and they play important roles in ensuring food security. The most common way to collect insects are from the wild, which is seasonal with limited availability and has an increasing demand resulting in a disruption to the ecosystem. There is a growing interest shown in rearing insects for commercial purposes, and an industrial scale production will be required to ensure steady supplies. Industrial production will need to take into account the living environment of insects, the nutritional composition of their feed and the overall efficiency of the production system. We provide a short overview on the consumption of and rearing insects in Africa, Asia and Europe. For Africa, a snapshot is given for Nigeria, Ghana, Central African Republic, Kenya and Uganda, while the following countries are reported for Asia: China, Japan, Lao People's Democratic Republic, Thailand and Vietnam. In addition, a list of insect species with the highest potential for food and feed in the European Union is provided with some reference to The Netherlands and Finland. The review concludes that there is need to better understand the rearing and farming procedures that will yield high quality edible insects in Africa, Asia and Europe.     

The use of edible insect proteins in food: Challenges and issues related to their functional properties

Over the past decade, the potential of edible insects as a novel ingredient in high value-added products has been investigated to find alternatives to conventional protein sources that are expensive, over-exploited and harmful to the environment. This review assesses the state of insects as an alternative protein source from production to consumption. More specifically, this review details the conventional procedures related to the production of insect flours as well as insect-derived ingredients such as protein concentrates and isolates. As a source of alternative protein in food ingredient formulations, the available data on the functionalities of edible insect ingredients is also examined and compared to conventional animal- and plant-based protein sources. Finally, the major challenges facing entomophagy in the mainstream food industry are explored. This review highlights the fact that insect proteins can serve as functional ingredients in food preparation. However, additional comparative studies are required to assess the functionality of various insect proteins compared to conventional proteins, regardless of processing method. To be incorporated into large scale industries, more research is needed to optimize processing methods to obtain the best compromise between cost-effectiveness, functionality, tastiness and sustainability, while ensuring consumer safety.     

可食用昆虫资源的利用历史、现状及展望

可食用昆虫作为补充食品，为农村地区的人口提供了重要的营养、经济和生态价值。本文综述了可食用昆虫资源的研究进展，包括可食用昆虫资源的利用历史、在全球的种类与分布、东西方国家对此的态度倾向等，并根据目前的现状，就可食用昆虫食品的开发利用提出了一些合理化的建议。     

An update on the processing of high‐protein rice products

The component of protein in rice, at 7–9% by weight, is relatively low, but the total amount of rice protein potentially available is significant because the production of rice worldwide, at 380 million tons annually, is huge. Rice proteins are recognized as nutritional, hypoallergenic, and healthy for human consumption, and rice protein products have been in demand in recent years. However, because of difficulties in the processing, rice protein products, particularly high‐protein content ones, have not been readily available. Two of the main sources of rice protein, rice bran and, to a lesser extent, broken rice kernels, have been under‐used and under‐priced. This report provides an update on the processing of these sources for rice proteins. Methods of protein processing are highlighted including the traditional alkaline extraction, enzyme‐assisted extraction, and the novel uses of physical treatment prior to water extraction. Also discussed are effects of processing on the functional and nutritional properties of rice protein.     

Nutritional composition and safety aspects of edible insects

Insects, a traditional food in many parts of the world, are highly nutritious and especially rich in proteins and thus represent a potential food and protein source. A compilation of 236 nutrient compositions in addition to amino acid spectra and fatty acid compositions as well as mineral and vitamin contents of various edible insects as derived from literature is given and the risks and benefits of entomophagy are discussed. Although the data were subject to a large variation, it could be concluded that many edible insects provide satisfactorily with energy and protein, meet amino acid requirements for humans, are high in MUFA and/or PUFA, and rich in several micronutrients such as copper, iron, magnesium, manganese, phosphorous, selenium, and zinc as well as riboflavin, pantothenic acid, biotin, and in some cases folic acid. Liabilities of entomophagy include the possible content of allergenic and toxic substances as well as antinutrients and the presence of pathogens. More data are required for a thorough assessment of the nutritional potential of edible insects and proper processing and decontamination methods have to be developed to ensure food safety.     

果蔬和水产品新型干燥预处理技术研究进展及未来展望

果蔬和水产品营养价值丰富,但含水率较高,极易引起微生物生长繁殖,进而导致腐败变质.干燥是延长果蔬和水产品货架期的有效途径,但干燥时间长、干制品品质差是限制该领域发展的瓶颈问题.采用热力或非热力预处理可有效提高干燥效率,改善干制品品质.基于此,本文综述了果蔬和水产品新型烫漂(高湿气体射流冲击烫漂、红外辐射烫漂、微波烫漂、...     

Performance of Drying Technologies to Ensure Microbial Safety of Dried Fruits and Vegetables

Dried fruits, vegetables, herbs, and spices are produced in and sourced from many countries worldwide, but they have been increasingly reported to be involved in outbreaks and alerts due to the presence of foodborne pathogens such as Salmonella. These dried products are mainly produced by solar drying and conventional air drying, but a wide range of drying technologies are available. From a technological point of view the general trend is to optimize and standardize the drying process to ensure high‐quality products to be offered. Drying technologies are mainly evaluated for their performance to reduce water activity at low energy cost while maintaining good sensorial quality of the dried product. However, as low water activity foods are increasingly recognized to support microbial survival and dried products are often consumed as they are, or are used as ingredients in many ready‐to‐eat foods, there is increasing attention to the microbiological quality and safety aspects of these products. This review presents traditional and emerging technologies to dry fruits, vegetables, herbs, and spices and discusses their potential to inactivate bacteria and viruses throughout the drying process. Overall, the microbial inactivation effect of the presented technologies has not yet been thoroughly assessed, even for traditional methods like solar drying, conventional air drying, or freeze‐drying. Emerging technologies such as dielectric (assisted) drying and low‐pressure superheated steam drying have been shown to reduce microbial populations; however, the number of studies is still low. Very few studies have focused on viral inactivation during drying processes.     

A systematic review of nutrient composition data available for twelve commercially available edible insects,and comparison with reference values

BackgroundEdible insects have been proposed as a more environmentally sustainable and nutritious alternative to conventional livestock. In response to the promotion of insects as food and feed by the Food and Agriculture Organization of the United Nations, insect agriculture is now a growing industry across the world. Yet information regarding the nutritional composition of commercially available insect species is disparate in terms of data quality, the location of published sources, and the form in which data is presented.Scope and approachWe conducted a systematic review of all published nutrient composition data for twelve selected species of commercially available edible insect. Our objective was to create a nutrient composition table in line with INFOODS/EuroFIR guidelines, and to present the results in a standardised form that is easily comprehensible for nutritionists and policy-makers.Key findings and conclusionsOur results expose the low quality of data describing edible insect nutritional composition, when compared to INFOODS/EuroFIR recommendations. This calls attention to the need for greater adherence to international guidelines in this field. The data that were included in our final table show clear within-species variation in the proportion of both macro- and micronutrients. This highlights the importance of external factors such as feed and ecology in determining nutrient composition.     

New protein sources and food legislation: the case of edible insects and EU law

Growing global food demand has generated a greater interest in the consumption of new and diversified protein sources. Novel foodstuffs represent a challenge for food law as they need proper safety assessments before obtaining market permission. The case of edible insects and European law is a good representation of this issue because a selection of food grade insect species may be available on the European market in the coming years. However, European legislation does not explicitly address edible insects. Consequently, this has left a grey area, allowing different interpretations of the legislation among Member States. The aim of this paper is to analyse the challenge of the safe management of edible insects in the context of the current legal framework. The current Novel Food legislation, as well as the forthcoming version of the legislation, will be analysed and discussed in relation to edible insects. Particular attention will be paid to the evolution of legislation and to the experiences of both EU and non-EU countries. In recent years, a number of different stakeholders have supported the legalization of edible insect consumption in Europe, but market permission is just the first step towards a new framework for a novel food in a regulatory context. Once admitted, edible insects require proper rules to assure consumers and stakeholders of their benefits and safety. This overview highlights the need to develop clearer legislation to govern the future production and consumption of new food in Europe, provide guarantees to producers, and achieve consumer protection.     

Tenebrio molitor as a source of interesting natural compounds,their recovery processes,biological effects,and safety aspects

Nowadays, it is urgent to produce in larger quantities and more sustainably to reduce the gap between food supply and demand. In a circular bioeconomy vision, insects receive great attention as a sustainable alternative to satisfy food and nutritional needs. Among all insects, Tenebrio molitor (TM) is the first insect approved by the European Food Safety Authority as a novel food in specific conditions and uses, testifying its growing relevance and potential. This review holistically presents the possible role of TM in the sustainable and circular solution to the growing needs for food and nutrients. We analyze all high value-added products obtained from TM (powders and extracts, oils and fatty acids, proteins and peptides, and chitin and chitosan), their recovery processes (evaluating the best ones in technical and environmental terms), their nutritional and economical values, and their biological effects. Safety aspects are also mentioned. TM potential is undoubted, but some aspects still need to be discussed, including the health effects of substances and microorganisms in its body, the optimal production conditions (that affect product quality and safety), and TM capacity to convert by-products into new products. Environmental, economic, social, and market feasibility studies are also required to analyze the new value chains. Finally, to unlock the enormous potential of edible insects as a source of nutritious and sustainable food, it will be necessary to overcome the cultural, psychological, and regulatory barriers still present in Western countries.     

山药加工方法的研究进展

山药是一种药食兼用的蔬菜,营养丰富并且具有保健功效,深受消费者青睐。山药含水量高,不耐贮藏,季节性强,加强对山药加工技术研究意义重大。目前,山药的加工工艺仍然较为传统,且相关报道较少。本文介绍了鲜切、冷冻、热风干燥等传统山药加工工艺以及冷冻升华干燥、微波干燥、真空微波干燥、挤压膨化等脱水新技术在山药加工中的研究进展,指出了这些新技术在山药加工中的优势和研究方向,旨在为山药加工方法的进一步研究提供参考。     

The selected quality aspects of infrared-dried black soldier fly (Hermetia illucens) and yellow mealworm (Tenebrio molitor) larvae pre-treated by pulsed electric field

Drying is one of the most important steps in processing of edible insects biomass for their potential utilisation in food applications. In this study, the impact of pulsed electric field (PEF) pre-treatment (at E = 1.07 kV/cm and W_spec = 5 and 20 kJ/kg) on infrared-assisted air drying kinetics of black soldier fly (Hermetia illucens) and yellow mealworm (Tenebrio molitor) larvae has been evaluated. Moreover, microbial load and physical quality parameters of dried matter have been analyzed. The results show that PEF enhances the kinetics of water evaporation from insects biomass, especially in the range of the moisture ratio (MR) from 1.0 to 0.2. For instance, in the case of having been drying H. illucens larvae for 20 min, MR equalled 0.86, 0.75, and 0.72 for the untreated sample, 5 kJ/kg PEF-treated and 20 kJ/kg PEF-treated one, respectively. The effect of the PEF treatment was less visible in the case of H. illucens larvae and for low MR values. The PEF pre-treatment did not affect the water binding properties of dried insect biomass, regardless of species. However, the PEF pre-treated matter exhibited the same or even higher hygroscopic properties than the untreated ones. The difference in optical properties between untreated and PEF-treated samples was marginal. Nevertheless, for microbial contamination, 20 kJ/kg PEF treatment reduced the total number of microorganisms by 0.5–1.0 log cycle in comparison to the dried matter that had not been pre-treated. Nevertheless, the total number of microorganisms was too high to be feasible for food production purposes which would require additional operations to ensure food safety.Industrial relevanceThe interest in utilisation of insects as an alternative source of macronutrients for food and feed is growing tremendously. Drying is one of the most popular first steps in further processing technology applicable to insect biomass. Since air drying is one of the longest and the most energy consuming unit operation, there is a need to seek alternative methods that can be coupled with pre-treatment to enhance the process kinetics. In this paper, the combination of infrared drying of two species of insects preceded by pulsed electric field treatment has been discussed.     

Which insect species can best be proposed for human consumption?

Edible insects have become popular in the past few years not only in the scientific literature but in other media as well. One of the major advantages of entomophagy (eating insects) is said to be the great nutritional composition. Many sources report that insects (generally) have better nutritional characteristics than traditional protein sources. In our research, we aim to give a complete picture of the nutritional profile of insects using a multicriteria optimization method, sum of ranking differences. The materials we used are published results of different authors from the past few years. The proximate analysis tells that insects generally have a better nutritional profile than other meats. The situation is a bit different in the case of mineral content; hence some vegetables have excellent mineral sources but waxworm larvae were ranked in the first three. Additionally, waxworm larvae have the most similar amino acid pattern to the FAO recommendation for adults. Earthworm, house cricket, and mealworm larvae showed the most promising vitamin content; however, huge differences were observed between the developmental stages of insects. A detailed analysis of these differences on the example of mealworms showed that adults may present a better option from the nutritional point of view. Same measurements conducted by different authors on the same species show considerable differences; hence the comparison of the results of different publications is dubious and should be handled with care. Based on our results, insects have a promising nutritional profile and may become part of many food products in the future. Present status of knowledge allows to conclude; which insect is best suitable for human consumption.     

Insect tea,a wonderful work in the Chinese tea culture

Insect tea, listed in the “Compendium of Materia Medica” by Li Shizhen, is not only a traditional drink for the ethnic minority in southwest China, but also one of China's traditional export commodities. Insect tea is made of the feces of insects that feed on plants, and characterized by minimal dose, enjoyable tea flavor, few tea-residues, and superb transparency. Insect tea has been used to clear summer heat, protect the spleen and stomach, and facilitate digestion. Modern research has suggested that insect tea is safe and nutritional, and it has blood lipid lowering, antihypertensive and hypoglycemic effects. At present, due to the household production of insect tea, there are a variety of species of tea-producing insects and feeding plants. In the present review, we summarized the types, civilian applications, nutritional value, pharmacological activity and safety of insect tea, in an effort to provide scientific knowledge for future study.     

食用菌菌丝体的营养品质及其在肉制品中的应用

肉类及肉制品是人类日常饮食中获取营养物质的主要来源, 食用营养和健康的肉制品已成为人们健康饮食的消费观念。然而, 由于肉制品供应难以满足全球人口快速增长的需求、过量摄入红肉可能导致的健康隐患以及肉类生产对环境造成的负面影响等问题, 新型肉类替代品的出现为消费者提供了更多的选择。其中, 食用菌在我国具有悠久的食用历史, 其菌丝体的营养成分与子实体相近, 且栽培消耗的资源少。因此, 将食用菌菌丝体应用于肉制品中极具开发潜力。本文结合近年的研究成果, 主要介绍了当前典型工业栽培食用菌(双孢菇、香菇、平菇、金针菇)菌丝的性质特点和营养价值, 重点综述了食用菌菌丝蛋白的生产加工技术及其在肉制品中的应用, 并分析了目前食用菌菌丝体在肉制品中应用的阻碍因素, 为食用菌菌丝体肉制品的研发提供理论基础。