High Hydrostatic Pressure-Assisted Enzymatic Hydrolysis Affect Mealworm Allergenic Proteins

Unlocking the Potential of Insect-Based Proteins: Sustainable Solutions for Global Food Security and Nutrition

The present review highlights the potential of insect-based proteins to address the growing need for sustainable and secure food systems. The key findings suggest that edible insects offer a viable and environmentally friendly alternative to traditional livestock, requiring significantly less land, water, and feed while emitting lower levels of greenhouse gases. Insect farming can also reduce waste and recycle nutrients, supporting circular economy models. Nutritionally, insects provide high-quality protein, essential amino acids, and beneficial fats, making them valuable to human diets. Despite these benefits, this review emphasizes the need for comprehensive regulatory frameworks to ensure food safety, manage potential allergenicity, and mitigate contamination risks from pathogens and environmental toxins. Additionally, developing innovative processing technologies can enhance the palatability and marketability of insect-based products, promoting consumer acceptance. This review concludes that with appropriate regulatory support and technological advancements, insect-based proteins have the potential to significantly contribute to global food security and sustainability efforts.

Insects as Valuable Sources of Protein and Peptides: Production, Functional Properties, and Challenges

As the global population approaches 10 billion by 2050, the critical need to ensure food security becomes increasingly pronounced. In response to the urgent problems posed by global population growth, our study adds to the growing body of knowledge in the field of alternative proteins, entomophagy, insect-based bioactive proteolysates, and peptides. It also provides novel insights with essential outcomes for guaranteeing a safe and sustainable food supply in the face of rising global population demands. These results offer insightful information to researchers and policymakers tackling the intricate relationship between population expansion and food supplies. Unfortunately, conventional agricultural practices are proving insufficient in meeting these demands. Pursuing alternative proteins and eco-friendly food production methods has gained urgency, embracing plant-based proteins, cultivated meat, fermentation, and precision agriculture. In this context, insect farming emerges as a promising strategy to upcycle agri-food waste into nutritious protein and fat, meeting diverse nutritional needs sustainably. A thorough analysis was conducted to evaluate the viability of insect farming, investigate insect nutrition, and review the techniques and functional properties of protein isolation. A review of peptide generation from insects was conducted, covering issues related to hydrolysate production, protein extraction, and peptide identification. The study addresses the nutritional value and global entomophagy habits to elucidate the potential of insects as sources of peptides and protein. This inquiry covers protein and hydrolysate production, highlighting techniques and bioactive peptides. Functional properties of insect proteins' solubility, emulsification, foaming, gelation, water-holding, and oil absorption are investigated. Furthermore, sensory aspects of insect-fortified foods as well as challenges, including Halal and Kosher considerations, are explored across applications. Our review underscores insects' promise as sustainable protein and peptide contributors, offering recommendations for further research to unlock their full potential.

Analysis and Comparison of Proteomics of Placental Proteins from Cows Using Different Proteases

Newly found biochemical characteristics of the placenta can provide new insights for further studies on the possible markers of physiological/pathological pregnancy or the function of the placenta. We compared the proteome of the dairy cow placenta after enzymatic hydrolysis by three different proteases using a label-free mass spectrometry approach. In total, 541, 136, and 86 proteins were identified in the trypsin group (TRY), pepsin group (PEP), and papain group (PAP). By comparing the proteome of the PAP and TRY, PEP and TRY, and PEP and PAP groups, 432, 421, and 136 differentially expressed proteins were identified, respectively. We compared the up-regulated DEPs and down-regulated DEPs of each comparison group. The results show that the proteins identified by papain were mostly derived from the extracellular matrix and collagen, and were enriched in the relaxin signaling pathway and AGE-RAGE signaling pathway in diabetic complications; pepsin digestion was able to identify more muscle-related proteins, which were enriched in the lysosome, platelet activation, cardiac muscle contraction, the bacterial invasion of epithelial cells, and small cell lung cancer; trypsin mainly enzymatically degraded the extracellular matrix, blood particles, and cell-surface proteins that were enriched in arginine and proline metabolism, olfactory transduction proteasome, protein processing in the endoplasmic reticulum, pyruvate metabolism, and arrhythmogenic right ventricular cardiomyopathy (ARVC). In summary, these results provide insights into the discovery of the physiological functions of dairy cow placenta and the selection of proteases in dairy cow placenta proteomics.

Optimization of Water Lentil (Duckweed) Leaf Protein Purification: Identification, Structure, and Foaming Properties

Water lentil, commonly known as duckweed, is an aquatic plant with great agronomic potential, as it can double its biomass in less than 24 h and contains up to 45% leaf proteins on a dry matter basis. However, extracting proteins from leaves is an arduous process due to the complexity of the matrix, which limits their uses in the food industry. In this study, water lentil protein extraction by solubilization was maximized using response surface methodology. By heating at 80 °C at pH 11 with a water lentil powder concentration of 2% or 4% for 2 h, up to 77.8% of total proteins were solubilized. Then, by precipitating the solubilized proteins at pH 4, a protein purity of 57.6% combined with a total protein yield of 60.0% was achieved. To the best of our knowledge, this is the highest leaf protein extraction yield reported in the literature with such protein purity. Proteomics analyses showed that the protein concentrate was composed of around 85.0% RubisCO, and protein structure analyses using ATR-FTIR and DSC were linked to a high protein solubility in water at pH 7. Moreover, a 1.5% protein solution of the protein concentrate at pH 7 showed excellent foaming properties compared to a 10.3% protein egg white solution. It had a superior foaming capacity (194% vs. 122%, respectively) for the same foaming stability after 60 min, which confirms water lentil proteins' potential for human nutrition and food formulation.

Assessment of the Efficiency of Technological Processes to Modify Whey Protein Antigenicity

Whey is a by-product that represents a cheap source of protein with a high nutritional value, often used to improve food quality. When used as a raw material to produce hypoallergenic infant formulas (HIF), a processing step able to decrease the allergenic potential is required to guarantee their safe use for this purpose. In the present paper, thermal treatments, high hydrostatic pressure (HHP), and enzymatic hydrolysis (EH) were assessed to decrease the antigenicity of whey protein solutions (WPC). For monitoring purposes, a competitive ELISA method, able to detect the major and most allergenic whey protein β-lactoglobulin (BLG), was developed as a first step to evaluate the efficiency of the processes. Results showed that EH together with HHP was the most effective combination to reduce WPC antigenicity. The evaluation method proved useful to monitor the processes and to be employed in the quality control of the final product, to guarantee the efficiency, and in protein antigenicity reduction.

Emerging Protein Sources for Food Production and Human Nutrition

It is estimated that by 2050, the world’s population will be up to 9 billion [...]

The Review of Cooking, Drying, and Green Extraction Methods on General Nutritional Properties of Mealworms and Locusts

The processing of edible insects as an alternative source of nutrition may be a key driver in the development of a sustainable food and feed system. This review will study two industrial types of insects-mealworms and locusts-and summarize evidence related to the impact of processing on their micro- and macronutritional characteristics. The focus will be on their potential use as food for human consumption as opposed to animal feed. Literature has indicated that these two insects have the potential to provide protein and fat qualities comparable to or better than traditional mammalian sources. For example, mealworms-the larval form of the yellow mealworm beetlepossess a higher fat content, while adult locusts are rich in fibers, especially chitin. However, due to the different matrix and nutrient compositions, the processing of mealworms or locusts at a commercial scale needs to be tailored to minimize nutritional loss and maximize cost efficiency. The stages of preprocessing, cooking, drying, and extraction are the most critical control points for nutritional preservation. Thermal cooking applications such as microwave technology have demonstrated promising results, but the generation of heat may contribute to a certain nutritional loss. In an industrial context, drying using freeze dry is the preferred choice due to its uniformity, but it can be costly while increasing lipid peroxidation. During the extraction of nutrients, the use of green emerging technologies such as high hydrostatic pressure, pulsed electric field, and ultrasound may provide an alternative method to enhance nutrient preservation.

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Transformation of Seafood Side-Streams and Residuals into Valuable Products

Seafood processing creates enormous amounts of side-streams. This review deals with the use of seafood side-streams for transformation into valuable products and identifies suitable approaches for making use of it for different purposes. Starting at the stage of catching fish to its selling point, many of the fish parts, such as head, skin, tail, fillet cut-offs, and the viscera, are wasted. These parts are rich in proteins, enzymes, healthy fatty acids such as monounsaturated and polyunsaturated ones, gelatin, and collagen. The valuable biochemical composition makes it worth discussing paths through which seafood side-streams can be turned into valuable products. Drawbacks, as well as challenges of different aquacultures, demonstrate the importance of using the various side-streams to produce valuable compounds to improve economic performance efficiency and sustainability of aquaculture. In this review, conventional and novel utilization approaches, as well as a combination of both, have been identified, which will lead to the development of sustainable production chains and the emergence of new bio-based products in the future.

Impact of holder, high temperature short time and high hydrostatic pressure pasteurization methods on protein structure and aggregation in a human milk protein concentrate

This work evaluated the impact of high temperature short time (HTST, 72 °C, 15 s), high hydrostatic pressure (HHP, 400-600 MPa at 5 and 10 min) and Holder pasteurization (HoP, 62.5 °C, 30 min) on protein profile and aggregation in a human milk protein concentrate (HMPC). The structural changes induced in milk proteins were investigated in HMPC as well as in sedimentable and non-sedimentable fractions recovered after ultracentrifugation. The results showed that heat treatments induced more protein denaturation and aggregation than did HHP treatments. Indeed, heat-induced protein aggregates observed in HMPC and the sedimentable fraction were mainly composed of lactoferrin and α-lactalbumin. More specifically, the concentration of lactoferrin in HMPC decreased by 86% after HTST and HoP whereas no effect was observed after HHP treatment. These results show the potential of HHP processing as a pasteurization method for HMPC since it minimizes the impact on protein structure, which generally correlates to protein quality and bioactivity.

Effect of High Hydrostatic Pressure Intensity on Structural Modifications in Mealworm (Tenebrio molitor) Proteins

Processing edible insects into protein extracts may improve consumer acceptability. However, a better understanding of the effects of food processing on the proteins is needed to facilitate their incorporation into food matrices. In this study, soluble proteins from Tenebrio molitor (10% w/v) were pressurized using high hydrostatic pressure (HHP) at 70–600 MPa for 5 min and compared to a non-pressurized control (0.1 MPa). Protein structural modifications were evaluated using turbidity measurement, particle-size distribution, intrinsic fluorescence, surface hydrophobicity, gel electrophoresis coupled with mass spectrometry, and transmission electron microscopy (TEM). The observed decrease in fluorescence intensity, shift in the maximum emission wavelength, and increase in surface hydrophobicity reflected the unfolding of mealworm proteins. The formation of large protein aggregates consisting mainly of hexamerin 2 and ⍺-amylase were confirmed by protein profiles on gel electrophoresis, dynamic light scattering, and TEM analysis. The typical aggregate shape and network observed by TEM after pressurization indicated the potential involvement of myosin and actin in aggregate formation, and these were detected by mass spectrometry. For the first time, the identification of mealworm proteins involved in protein aggregation phenomena under HHP was documented. This work is the first step in understanding the mealworm protein–protein interactions necessary for the development of innovative insect-based ingredients in food formulations.

Revisiting Non-Thermal Food Processing and Preservation Methods-Action Mechanisms, Pros and Cons: A Technological Update (2016-2021)

The push for non-thermal food processing methods has emerged due to the challenges associated with thermal food processing methods, for instance, high operational costs and alteration of food nutrient components. Non-thermal food processing involves methods where the food materials receive microbiological inactivation without or with little direct application of heat. Besides being well established in scientific literature, research into non-thermal food processing technologies are constantly on the rise as applied to a wide range of food products. Due to such remarkable progress by scientists and researchers, there is need for continuous synthesis of relevant scientific literature for the benefit of all actors in the agro-food value chain, most importantly the food processors, and to supplement existing information. This review, therefore, aimed to provide a technological update on some selected non-thermal food processing methods specifically focused on their operational mechanisms, their effectiveness in preserving various kinds of foods, as revealed by their pros (merits) and cons (demerits). Specifically, pulsed electric field, pulsed light, ultraviolet radiation, high-pressure processing, non-thermal (cold) plasma, ozone treatment, ionizing radiation, and ultrasound were considered. What defines these techniques, their ability to exhibit limited changes in the sensory attributes of food, retain the food nutrient contents, ensure food safety, extend shelf-life, and being eco-friendly were highlighted. Rationalizing the process mechanisms about these specific non-thermal technologies alongside consumer education can help raise awareness prior to any design considerations, improvement of cost-effectiveness, and scaling-up their capacity for industrial-level applications.

Chemical Composition, Nutrient Quality and Acceptability of Edible Insects Are Affected by Species, Developmental Stage, Gender, Diet, and Processing Method

Edible insects have been considered as either nutritious food itemsper se, or as wholesome ingredients to various dishes and components of traditional subsistence. Protein, fat, mineral and vitamin contents in insects generally satisfy the requirements of healthy food, although there is considerable variation associated with insect species, collection site, processing method, insect life stage, rearing technology and insect feed. A comparison of available data(based on dry weight) showed that processing can improve the nutrient content, taste, flavour, appearance and palatability of insects, but that there are additional factors, which can impact the content and composition of insect species that have been recommended for consumption by humans. This review focuses on factors that have received little attention in connection with the task to improve acceptability or choice of edible insects and suggests ways to guarantee food security in countries where deficiencies in protein and minerals are an acute and perpetual problem. This review is meant to assist the food industry to select the most suitable species as well as processing methods for insect-based food products.

Induced Changes in Aroma Compounds of Foods Treated with High Hydrostatic Pressure: A Review

Since conventional thermal processing can have detrimental consequences on aroma compounds, non-thermal technologies such as high hydrostatic pressure (HHP) have been explored. HHP may alter the weak chemical bonds of enzymes. These changes can modify the secondary, tertiary, and quaternary structures of key enzymes in the production of aroma compounds. This can result in either an increase or decrease in their content, along with reactions or physical processes associated with a reduction of molecular volume. This article provides a comprehensive review of HHP treatment's effects on the content of lipid-derived aroma compounds, aldehydes, alcohols, ketones, esters, lactones, terpenes, and phenols, on various food matrices of vegetable and animal origin. The content of aldehydes and ketones in food samples increased when subjected to HHP, while the content of alcohols and phenols decreased, probably due to oxidative processes. Both ester and lactone concentrations appeared to decline due to hydrolysis reactions. There is no clear tendency regarding terpenes concentration when subjected to HHP treatments. Because of the various effects of HHP on aroma compounds, an area of opportunity arises to carry out future studies that allow optimizing and controlling the effect.

Effects of Hexane on Protein Profile, Solubility and Foaming Properties of Defatted Proteins Extracted from Tenebrio molitor Larvae

Inclusion of edible insects in human diets is increasingly promoted as a sustainable source of proteins with high nutritional value. While consumer acceptability remains the main challenge to their integration into Western food culture, the use of edible insects as meal and protein concentrate could decrease neophobia. The defatting of edible insects, mostly done with hexane, is the first step in producing protein ingredients. However, its impact on protein profiles and techno-functionality is still unclear. Consequently, this study compares the protein profiles of hexane-defatted and non-hexane-defatted yellow mealworm (Tenebrio molitor) meals and protein extracts, and evaluates the impact of hexane on protein solubility and foaming properties. Results showed that profiles for major proteins were similar between hexane-defatted and non-defatted samples, however some specific content differences (e.g., hexamerin 2) were observed and characterized using proteomic tools. Protein solubility was markedly lower for T. molitor meals compared to protein extracts. A large increase in the foaming capacity was observed for defatted fractions, whereas foam stability decreased similarly in all fractions. Consequently, although the hexane-defatting step was largely studied to produce edible insect protein ingredients, it is necessary to precisely understand its impact on their techno-functional properties for the development of food formulations.

Recent Trends in Pretreatment of Food before Freeze-Drying

Drying is among the most important processes and the most energy-consuming techniques in the food industry. Dried food has many applications and extended shelf life. Unlike the majority of conventional drying methods, lyophilization, also known as freeze-drying (FD), involves freezing the food, usually under low pressure, and removing water by ice sublimation. Freeze-dried materials are especially recommended for the production of spices, coffee, dried snacks from fruits and vegetables and food for military or space shuttles, as well as for the preparation of food powders and microencapsulation of food ingredients. Although the FD process allows obtaining dried products of the highest quality, it is very energy- and time consuming. Thus, different methods of pretreatment are used for not only accelerating the drying process but also retaining the physical properties and bioactive compounds in the lyophilized food. This article reviews the influence of various pretreatment methods such as size reduction, blanching, osmotic dehydration and application of pulsed electric field, high hydrostatic pressure or ultrasound on the physicochemical properties of freeze-dried food and drying rate.

Functionality of Cricket and Mealworm Hydrolysates Generated after Pretreatment of Meals with High Hydrostatic Pressures

The low consumer acceptance to entomophagy in Western society remains the strongest barrier of this practice, despite these numerous advantages. More positively, it was demonstrated that the attractiveness of edible insects can be enhanced by the use of insect ingredients. Currently, insect ingredients are mainly used as filler agents due to their poor functional properties. Nevertheless, new research on insect ingredient functionalities is emerging to overcome these issues. Recently, high hydrostatic pressure processing has been used to improve the functional properties of proteins. The study described here evaluates the functional properties of two commercial insect meals (Gryllodes sigillatus and Tenebrio molitor) and their respective hydrolysates generated by Alcalase®, conventionally and after pressurization pretreatment of the insect meals. Regardless of the insect species and treatments, water binding capacity, foaming and gelation properties did not improve after enzymatic hydrolysis. The low emulsion properties after enzymatic hydrolysis were due to rapid instability of emulsion. The pretreatment of mealworm meal with pressurization probably induced protein denaturation and aggregation phenomena which lowered the degree of hydrolysis. As expected, enzymatic digestion (with and without pressurization) increased the solubility, reaching values close to 100%. The pretreatment of mealworm meal with pressure further improved its solubility compared to control hydrolysate, while pressurization pretreatment decreased the solubility of cricket meal. These results may be related to the impact of pressurization on protein structure and therefore to the generation of different peptide compositions and profiles. The oil binding capacity also improved after enzymatic hydrolysis, but further for pressure-treated mealworm hydrolysate. Despite the moderate effect of pretreatment by high hydrostatic pressures, insect protein hydrolysates demonstrated interesting functional properties which could potentially facilitate their use in the food industry.