Recent advances in alleviating food allergenicity through fermentation

Proteomic characterization of peanut flour fermented by Rhizopus oryzae

Fermentation alters the protein content and composition of foods. To characterize fungal catabolism of peanut proteins, defatted peanut flour was fermented by Rhizopus oryzae (R. oryzae) for up to 48 h and evaluated by SDS-PAGE, mass spectrometry, and antibody binding. A clear change in peanut protein migration was observed by SDS-PAGE after 16 h of fermentation. Mass spectrometric analysis indicated changes in allergen peptides and R. oryzae proteins. Several low molecular weight allergen fragments produced during fermentation were identified by mass spectrometry. Immunoassays using anti-peanut allergen antibodies demonstrated reduced allergen content as early as 16 h of fermentation. However, ELISA with peanut allergic IgE indicated only slightly reduced allergen binding even after 48 h. These results indicate that while R. oryzae fermentation efficiently metabolizes peanut allergens, significant IgE binding remains in lower molecular mass peptides, and therefore R. oryzae fermented peanut products would not be safe for peanut allergic individuals.

Recent advance in sesame allergens: Influence of food processing and their detection methods

Sesame (Sesamum indicum L.) is a valuable oilseed crop with numerous nutritional benefits containing a diverse range of bioactive compounds. However, sesame is also considered an allergenic food that triggers various mild to severe adverse reactions (e.g., anaphylaxis). Strict dietary avoidance of sesame components is the best option to protect the sensitized consumers. Sesame or sesame-derived foods are always consumed after certain food processing operations, which would cause a considerable impact on the structure of sesame proteins, changing their sensitization capacity and detectability. In the review, the molecular structure properties, and immunological characteristics of the sesame allergens were described. Meanwhile, the influence of food processing techniques on sesame proteins and the relevant detection techniques used for the sesame allergens quantification are also emphasized critically. Hopefully, this review could provide valuable insight into the development and management for the new "Big Eight" sesame allergen in food industry.

Bacteriocin production by lactic acid bacteria using ice cream co-product as the fermentation substrate

Ice cream manufacture commonly results in the accumulation of wasted product that contains valuable food-grade quality components, including fat, carbohydrates, and protein. Methods have been developed for recovering the fat from this waste stream, but this results in the generation of a co-product rich in fermentable carbohydrates. This study aimed to investigate the potential for using this co-product as a fermentation substrate for production of antimicrobial peptides, called bacteriocins, by dairy starter cultures. Results showed that Streptococcus thermophilus B59671 and Lactococcus lactis 11454 produced the broad-spectrum bacteriocins thermophilin 110 and nisin, respectively, when the fermentation substrate was melted ice cream, or a co-product generated by a modified butter churning technique. Bacteriocin production varied depending on the brand and variety of vanilla ice cream used in this study. When an alternate enzyme-assisted fat extraction technique was used, S. thermophilus metabolism was impaired within the resulting co-product, and thermophilin 110 production was not observed. Lactococcus lactis was still able to grow in this co-product, but antimicrobial activity was not observed. Results from this study suggest the co-product generated when using the churning technique is a better choice to use as a base medium for future studies to optimize bacteriocin production.

Lactic acid bacteria modulate the gastrointestinal digestive behavior of soy glycinin and correlation with its immunoreactivity: a peptidomic study

Lactic acid bacterial fermentation helps reduce the immunoreactivity of soy protein. Nevertheless, the effect of lactic acid bacterial fermentation on a particular soy allergen and the consequent dynamic change of epitopes during gastrointestinal digestion are unclear. In this study, soy glycinin was isolated and an in vitro dynamic gastrointestinal model was established to investigate the dynamic change in the immunoreactivity and peptide profile of unfermented (UG) and fermented glycinin (FG) digestates. The results demonstrated that the FG intestinal digestate had a lower antigenicity (0.08%-0.12%) and IgE-binding capacity (1.49%-3.61%) towards glycinin at the early (I-5) and middle (I-30) stages of gastrointestinal digestion, especially those prepared at 2% (w/v) protein concentration. Peptidomic analysis showed that the glycinin subunits G1 and G2 were the preferred ones to release the most abundant peptides, whereas G2, G4, and G5 had an elevated epitope-cleavage rate in FG at stages I-5 and I-30. Three-dimensional modeling revealed that fermentation-induced differential degradation epitopes in gastrointestinal digestion were predominantly located in the α-helix and β-sheet structures. They were closely correlated with the reduced immunoreactivity of soy glycinin.

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.

Modulation of soy protein immunoreactivity by different matrix structures of lactic acid bacterium-induced soy protein gels: Epitope destruction during in vitro gastroduodenal digestion and absorption

Soy allergy is a common health problem. Food structure may change the gastroduodenal digestion and absorption of soy proteins, thus leading to the modulation of the immunoreactivity of soy proteins. In this study, lactic acid bacterium (LAB)-fermented soy protein isolates (FSPIs) were prepared at four concentrations (0.2 %-5.0 %, w/v) to present various matrix structures (nongel, NG; weak gel, WG; medium gel, MG; and firm gel, FG) and subjected to in vitro dynamic gastroduodenal digestion model. The results of sandwich enzyme-linked immunosorbent and human serum IgE binding capacity assays demonstrated that FSPI gels, especially the FSPI-MG/WG digestates obtained at the early and medium stages of duodenal digestion (D-5 and D-30), possessed greater potency in immunoreactivity reduction than FSPI-NG and reduced to 1.9 %-68.3 %. The transepithelial transport study revealed that the immunoreactivity of FSPI-MG/WG D-5 and D-30 digestates decreased through the stimulation of interferon-γ production and the induction of dominant Th1/Th2 differentiation. Peptidomics and bioinformatics analyses illustrated that compared with FSPI-NG, the FSPI-gel structure promoted the epitope degradation of the major allergens glycinin G2/G5, β-conglycinin α/β subunit, P34, lectin, trypsin inhibitor, and basic 7S globulin. Spatial structure analysis showed that FSPI-gel elicited an overall promotion in the degradation of allergen epitopes located in interior and exterior regions and was dominated by α-helix and β-sheet secondary structures, whereas FSPI-MG/WG promoted the degradation of epitopes located in the interior region of glycinin/β-conglycinin and exterior region of P34/basic 7S globulin. This study suggested that the FSPI-gel structure is a promising food matrix for decreasing the allergenic potential of allergenic epitopes during gastroduodenal digestion and provided basic information on the production of hypoallergenic soy products.

Allergen Stability in Food Allergy: A Clinician's Perspective

PURPOSE OF REVIEW

The globally rising food allergy prevalence is associated with the urgent need for new disease prevention methods, efficient treatment, and reliable risk assessment methods for characterization of food allergens. Due to inter-individual variations in the digestive system, food allergens are degraded to a different extent in each person. Food processing also influences allergen digestion.

RECENT FINDINGS

In this review, we provide an overview of the digestive system with focus on relevance for food allergy. Main food proteins causing allergic reactions are evaluated, and the combined role of food processing and digestion for allergen stability is highlighted. Finally, clinical implications of this knowledge are discussed. Recent literature shows that allergen digestibility is dependent on food processing, digestive conditions, and food matrix. Digestion affects proteins allergenicity. It is currently not possible to predict the immunogenicity of allergens solely based on protein stability.

The Differences in Protein Degradation and Sensitization Reduction of Mangoes between Juices and Pieces Fermentation

Given the allergic reaction caused by mangoes, nonthermal food technologies for allergenicity reduction are urgently desired. This study aimed to assess the impact of kombucha fermentation on the allergenicity of mangoes. The total proteins, soluble proteins, peptides, amino acid nitrogen, the SDS-PAGE profiles of the protein extracts, and immunoreactivity of the sediment and supernatant were measured in two fermentation systems (juices and pieces fermentation). Throughout the fermentation, the pH decreased from about 4.6 to about 3.6, and the dissolved oxygen reduced about 50% on average. However, the protein degradation and sensitization reduction of mangoes were different between the two fermentation systems. In juices fermentation, there was a drop in proteins and peptides but an increase in amino acids, due to the conversion of proteins and peptides into amino acids both in the supernatant and sediment. The allergenicity decreased both in the solid and liquid phases of juices fermentation. In pieces fermentation, proteins and peptides were decreased in the solid phase but increased in the liquid phase. This was due to the fact that proteins and peptides were partly transported into the culture liquid, resulting in a decrease of allergenicity in fruit pieces and an increase in culture liquid. The principal component analysis results showed that the fermentation type had significant effects on the protein degradation and sensitization reduction, while mango variety had no significant effect. These results demonstrate that kombucha fermentation can reduce the allergenicity of mangoes, and it is more effective in juices fermentation than in pieces fermentation. The present study provides a theoretical basis for developing hypoallergenic mango products.

Recent advances in selective allergies to mammalian milk proteins not associated with Cow's Milk Proteins Allergy

Cow's milk proteins allergy (CMA) is an atypical immune system response to cow's milk and dairy products. It's one of the most common food allergies in children affecting 8% of the total pediatric population pediatric population. This comprehensive review examines recent studies in CMA, especially regarding mammalian milk allergies such as goat's, sheep's, buffalo's, camel's, mare's and donkey's milk allergies in order to increase awareness of these selective allergies and to reduce allergy risks for those who have them. The consumption of other mammalian milk types is not recommended because of the significant homology between milk proteins from cow, sheep, goat and buffalo resulting in clinical cross-reactivity. However, camel's, mare's or donkey's milk may be tolerated by some allergic patients. Selective mammalian milk allergies are unusual and rare disorders characterized by severe symptoms including angio-oedema, urticaria, respiratory manifestations and anaphylaxis. Based on the reported allergic cases, cheese products including Ricotta, Romano, Pecorino and Mozzarella, are considered as the most common source of allergens especially in goat's, sheep's and buffalo's milk allergies, while the major allergens in donkey's and mare's milk seems to be whey proteins including lysozyme, α-lactalbumin and β-lactogloblin due to the low casein/whey proteins ratio in equine's milk.

Conventional solid-state fermentation impacts the white lupin proteome reducing the abundance of allergenic peptides

The demand for high-quality and sustainable protein sources is on the rise. Lupin is an emerging plant-based source of protein with health-enhancing properties; however, the allergenic potential of lupins limits their widespread adoption in food products. A combination of discovery and targeted quantitative proteome measurements was used to investigate the impact of solid-state fermentation induced by Rhizopus oligosporus on the proteome composition and allergenic protein abundances of white lupin seed. In total, 1,241 proteins were uniquely identified in the fermented sample. Moreover, the effectiveness of the solid-state fermentation in reducing the abundance of the tryptic peptides derived from white lupin allergens was demonstrated. Comparably, a greater decrease was noted for the major white lupin allergen based on β-conglutin peptide abundances. Hence, conventional solid-state fermentation processing can be beneficial for reducing the potential allergenicity of lupin-based foods. This finding will open new avenues for unlocking the potential of this under-utilised legume.

Two Pediatric Cases of Food Protein-Induced Enterocolitis Syndrome to Soy Eaten as an Infant Food

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy that can be caused not only by infant formula but also by infant food. Herein, we report two pediatric cases of FPIES to solid soy foods, such as tofu. The patients presented with repetitive vomiting after eating the trigger food as infant food. Although both cases promptly recovered following the cessation of the trigger food, one case required rapid intravenous hydration for compensated shock. Both cases were diagnosed with FPIES to soy based on the typical presentation and parental interviews regarding food exposure. One case had a positive response to an oral food challenge for tofu, and both cases were negative for soy-specific IgE. One of our cases did not develop FPIES from fermented soy products despite having soy-triggered FPIES. The fermentation process may reduce the allergenicity of soy, but further evidence is required to confirm this hypothesis. There are various trigger foods for solid food FPIES (SFF), and these differ among countries. Solid food FPIES to soy is more common in Japan than in other countries due to the frequent use of tofu in infant food. Increased international awareness of the possibility of tofu-triggered FPIES may be warranted due to the rising global use of tofu in infant food.

Peanut Allergenicity: An Insight into Its Mitigation Using Thermomechanical Processing

Peanuts are the seeds of a legume crop grown for nuts and oil production. Peanut allergy has gained significant attention as a public health issue due to its increasing prevalence, high rate of sensitization, severity of the corresponding allergic symptoms, cross-reactivity with other food allergens, and lifelong persistence. Given the importance of peanuts in several sectors, and taking into consideration the criticality of their high allergic potential, strategies aiming at mitigating their allergenicity are urgently needed. In this regard, most of the processing methods used to treat peanuts are categorized as either thermal or thermomechanical techniques. The purpose of this review is to provide the reader with an updated outlook of the peanut’s allergens, their mechanisms of action, the processing methods as applied to whole peanuts, as well as a critical insight on their impact on the allergenicity. The methods discussed include boiling, roasting/baking, microwaving, ultrasonication, frying, and high-pressure steaming/autoclaving. Their effectiveness in alleviating the allergenicity, and their capacity in preserving the structural integrity of the treated peanuts, were thoroughly explored. Research data on this matter may open further perspectives for future relevant investigation ultimately aiming at producing hypoallergenic peanuts.

Raw milk kefir: microbiota, bioactive peptides, and immune modulation

This study aims to characterize the microbiota and peptidomic composition of raw milk kefir, and to address the potential anti-allergic effects of raw milk kefir using validated research models for food allergy. Raw milk kefir was produced after incubation with a defined freeze-dried starter culture. Kefir was sampled during fermentation at seven time intervals. For comparison, kefir was also prepared from heat-treated milk. Peptide compositions were determined for the raw and heated milk, and kefir end products made from these milks. In a murine food allergy model, the two kefir end products were investigated for their allergy modulating effects. In both kefirs, we identified amplicon sequence variants identical to those in the starter culture, matching the bacteria Lactococcus lactis, Streptococcus thermophilus, Leuconostoc and the yeast Debaryomyces. In raw milk kefir, additional sequence variants of Lactococcus lactis and the yeasts Pichia and Galactomyces could be identified, which were absent in heated milk kefir. Analysis of peptide compositions in both kefirs indicated that the number and intensity of peptides drastically increased after fermentation. Heating of the milk negatively affected the diversity of the peptide composition in kefir. Only raw milk kefir suppressed the acute allergic skin response to the food allergen ovalbumin in sensitised mice. These effects coincided with differences in the T-cell compartment, with lower percentages of activated Th1 cells and IFNg production after treatment with kefir made from heated milk. The results of this study indicate specific properties of raw milk kefir that may contribute to its additional health benefits.

Alteration of the allergenicity of cow's milk proteins using different food processing modifications

Milk is an essential source of protein for infants and young children. At the same time, cow's milk is also one of the most common allergenic foods causing food allergies in children. Recently, cow's milk allergy (CMA) has become a common public health issue worldwide. Modern food processing technologies have been developed to reduce the allergenicity of milk proteins and improve the quality of life of patients with CMA. In this review, we summarize the main allergens in cow's milk, and introduce the recent findings on CMA responses. Moreover, the reduced effects and underlying mechanisms of different food processing techniques (such as heating, high pressure, γ-ray irradiation, ultrasound irradiation, hydrolysis, glycosylation, etc.) on the allergenicity of cow's milk proteins, and the application of processed cow's milk in clinical studies, are discussed. In addition, we describe the changes of nutritional value in cow's milk treated by different food processing technologies. This review provides an in-depth understanding of the allergenicity reduction of cow's milk proteins by various food processing techniques.

Crustacean shellfish allergens: influence of food processing and their detection strategies

Despite the increasing popularity of crustacean shellfish among consumers due to their rich nutrients, they can induce a serious allergic response, sometimes even life-threatening. In the past decades, a variety of crustacean allergens have been identified to facilitate the diagnosis and management of crustacean allergies. Although food processing techniques can ease the risk of crustacean shellfish allergy, no available processing methods to tackle crustacean allergies thoroughly. Strict dietary avoidance of crustacean shellfish and its component is the best option for the protection of sensitized individuals, which should rely on the compliance of food labeling and, as such, on their verification by sensitive, reliable, and accurate detection techniques. In this present review, the physiochemical properties, structure aspects, and immunological characteristics of the major crustacean allergens have been described and discussed. Subsequently, the current research progresses on how various processing techniques cause the alterations and modifications in crustacean allergens to produce hypoallergenic crustacean food products were summarized and discussed. Particularly, various analytical methodologies employed in crustacean shellfish allergen detection, and the effect of food processing and matrix on these techniques, are also herein emphasized for the appropriate selection of analytical detection tools to safeguard consumers safety.

Gastrointestinal fate of food allergens and its relationship with allergenicity

Food allergens are closely related to their gastrointestinal digestion fate, but the changes in food allergens during digestion and related mechanisms are quite complicated. This review presents in detail digestion models for predicting allergenicity, the fates of food allergens in oral, gastric and duodenal digestion, and the applications of digestomics in mapping IgE-binding epitopes of digestion-resistant peptides. Moreover, this review highlights the structure-activity relationships of food allergens during gastrointestinal digestion. Digestion-labile allergens may share common structural characteristics, such as high flexibility, rendering them easier to be hydrolyzed into small fragments with decreased or eliminated allergenicity. In contrast, the presence of disulfide bonds, tightly wound α-helical structures, or hydrophobic domains in food allergens helps them resist gastrointestinal digestion, stabilizing IgE-binding epitopes, thus maintaining their sensitization. In rare cases, digestion leads to increased allergenicity due to exposure of new epitopes. Finally, the action of the food matrix and processing on the digestion and allergenicity of food allergens as well as the underlying mechanisms was overviewed. The food matrix can directly act on the allergen by forming complexes or new epitopes to affect its gastrointestinal digestibility and thereby alter its allergenicity or indirectly affect the allergenicity by competing for enzymatic cleavage or influencing gastrointestinal pH and microbial flora. Several processing techniques attenuate the allergenicity of food proteins by altering their conformation to improve susceptibility to degradation by digestive enzymes. Given the complexity of food components, the food itself rather than a single allergen should be used to obtain more accurate data for allergenicity assessment. PRACTICAL APPLICATION: The review article will help to understand the relationship between food protein digestion and allergenicity, and may provide fundamental information for evaluating and reducing the allergenicity of food proteins.

Fermented Food in Asthma and Respiratory Allergies—Chance or Failure?

In the last few decades, a dramatic increase in the global prevalence of allergic diseases and asthma was observed. It was hypothesized that diet may be an important immunomodulatory factor influencing susceptibility to allergic diseases. Fermented food, a natural source of living microorganisms and bioactive compounds, has been demonstrated to possess health-promoting potentials and seems to be a promising strategy to reduce the risk of various immune-related diseases, such as allergic diseases and asthma. The exact mechanisms by which allergic diseases and asthma can be alleviated or prevented by fermented food are not well understood; however, its potential to exert an effect through modulating the immune response and influencing the gut microbiota has been recently studied. In this review, we provide the current knowledge on the role of diet, including fermented foods, in preventing or treating allergic diseases and asthma.

Detection of Allergenic Proteins in Foodstuffs: Advantages of the Innovative Multiplex Allergen Microarray-Based Immunoassay Compared to Conventional Methods

Several factors can affect the allergen content and profile of a specific food, including processing procedures often leading to a decrease in allergenicity, although no change, or even an increase, have also been reported. Evaluation of the effectiveness of a processing procedure requires the availability of reliable methodologies to assess the variation in molecules able to induce allergic reactions in the analyzed food. Conventional and innovative strategies and methodologies can be exploited to identify allergenic proteins in foodstuffs. However, depending on the specific purposes, different methods can be used. In this review, we have critically reviewed the advantages of an innovative method, the multiplex allergen microarray-based immunoassay, in the detection of allergens in foodstuffs. In particular, we have analyzed some studies reporting the exploitation of an IgE-binding inhibition assay on multiplex allergen biochips, which has not yet been reviewed in the available literature. Unlike the others, this methodology enables the identification of many allergenic proteins, some of which are still unknown, which are recognized by IgE from allergic patients, with a single test. The examined literature suggests that the inhibition test associated with the multiplex allergen immunoassay is a promising methodology exploitable for the detection of IgE-binding proteins in food samples.

A Combined Proteomic and Metabolomic Strategy for Allergens Characterization in Natural and Fermented Brassica napus Bee Pollen

Bee pollen is consumed for its nutritional and pharmacological benefits, but it also contains hazardous allergens which have not been identified. Here, we identified two potential allergens, glutaredoxin and oleosin-B2, in Brassica napus bee pollen using mass spectrometry-based proteomics analyses, and used bioinformatics to predict their antigenic epitopes. Comparison of fermented (by Saccharomyces cerevisiae) and unfermented bee pollen samples indicated that glutaredoxin and oleosin-B2 contents were significantly decreased following fermentation, while the contents of their major constituent oligopeptides and amino acids were significantly increased based on metabolomics analyses. Immunoblot analysis indicated that the IgE-binding affinity with extracted bee pollen proteins was also significantly decreased after fermentation, suggesting a reduction in the allergenicity of fermented bee pollen. Furthermore, fermentation apparently promoted the biosynthesis of L-valine, L-isoleucine, L-tryptophan, and L-phenylalanine, as well as their precursors or intermediates. Thus, fermentation could potentially alleviate allergenicity, while also positively affecting nutritional properties of B. napus bee pollen. Our findings might provide a scientific foundation for improving the safety of bee pollen products to facilitate its wider application.

The Conformational Structural Change of Soy Glycinin via Lactic Acid Bacteria Fermentation Reduced Immunoglobulin E Reactivity

This study investigated the fermentation of isolated soy glycinin by using the Lactiplantibacillus plantarum B1-6 strain, its reduction effect on immunoglobulin E (IgE) reactivity, the relationship with protein aggregation/gelation state and conformational changes. Fermentation was performed under different glycinin concentrations (0.1%, 0.5%, 1% and 2%, w/v) and varied fermentation terminal pH levels (FT-pH) (pH 6.0, 4.5, 4.0 and 3.5). L. plantarum B1-6 showed potency in reducing immunoreactivity to 0.10–69.85%, as determined by a sandwich enzyme-linked immunosorbent assay. At a FT-pH of 6.0 and 4.5, extremely low IgE reactivity (0.1–22.32%) was observed. Fermentation resulted in a great increase (2.31–6.8-fold) in particle size and a loss of intensity in A3 and basic subunits. The conformation of glycinin was altered, as demonstrated by improved surface hydrophobicity (1.33–7.39-fold), decreased intrinsic fluorescence intensity and the α-helix structure. Among the four selected concentrations, glycinin at 1% (w/v, G-1) evolved the greatest particles during fermentation and demonstrated the lowest immunoreactivity. Principal component analysis confirmed that particle size, intrinsic fluorescence intensity, α-helix and ionic bond were closely related to immunoreactivity reduction.