Application of gamma irradiation for inhibition of food allergy

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.

Effect of Gamma Irradiation on the PLA-Based Blends and Biocomposites Containing Rosemary Ethanolic Extract and Chitosan

The irradiation of polymeric materials with ionizing radiation (γ-rays, X-rays, accelerated electrons, ion beams, etc.) may lead to disproportion, hydrogen abstraction, arrangements, degradation, and/or the formation of new bonds. The purpose of this paper is to evaluate the effect of gamma irradiation on some new poly(lactic acid) (PLA)-based blends and biocomposites, which is crucial when they are used for food packaging or medical purposes. The polymeric blends and biocomposites based on PLA and rosemary ethanolic extract (R) and poly(ethylene glycol) (PEG) (20 wt%) plasticized PLA, chitosan (CS) (3–6 wt%) and R (0.5 wt%) biocomposites were subjected to gamma irradiation treatment using three low γ-doses of 10, 20, and 30 kGy. The effect of irradiation was evaluated by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), thermogravimetry (TG), chemiluminescence method (CL), migration studies, and antibacterial activity tests. It was found that in comparison with neat PLA, the gamma irradiation in the oxidative conditions of the PLA-based blends and biocomposites, causes modifications in the structure, morphology, and thermal properties of the materials depending on irradiation dose and the presence of natural additives such as rosemary and chitosan. It was established that under a gamma-irradiation treatment with dose of 10–20 kGy, the PLA materials showed minor changes in structure and properties being suitable for application in packaging and in addition after irradiation with such doses their antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Salmonella typhimurium is improved.

Evaluation of antigenicity and nutritional properties of enzymatically hydrolyzed cow milk

While enzymatic hydrolysis is an effective method for lowering the antigenicity of cow milk (CM), research regarding the antigenicity and nutritional traits of CM hydrolysate is limited. Here, we evaluated the protein content, amino acid composition, sensory traits, color, flow behavior, and antigenicity of CM following enzymatic hydrolysis. The results showed that enzymatic hydrolysis increased the degree of hydrolysis, destroyed allergenic proteins, including casein, β-lactoglobulin, and ɑ-lactalbumin, and significantly increased the content of free amino acids and nutritional quality. In particular, the antigenicity of CM was significantly reduced from 44.05 to 86.55% (P < 0.5). Simultaneously, the taste, color, and flow behavior of CM were altered, the sweetness and richness intensity decreased significantly (P < 0.5), and astringency and bitterness were produced. A slightly darker and more yellow color was observed in CM hydrolysate. In addition, apparent viscosity decreased and shear stress significantly increased with increasing shear rate intensity. The results will provide a solid theoretical foundation for the development of high-quality hypoallergenic dairy products.

Food irradiation: a promising technology to produce hypoallergenic food with high quality

The increasing incidence of food allergy cases is a public health problem of global concern. Producing hypoallergenic foods with high quality, low cost, and eco-friendly is a new trend for the food industry in the coming decades. Food irradiation, a non-thermal food processing technology, is a powerful tool to reduce the allergenicity with the above advantages. This review presents a summary of recent studies about food irradiation to reduce the allergenicity of food, including shellfish, soy, peanut, milk, tree nut, egg, wheat and fish. Principles of food irradiation, including mechanisms of allergenicity-reduction, irradiation types and characteristics, are discussed. Specific effects of food irradiation are also evaluated, involving microbial decontamination, improvement or preservation of nutritional value, harmful substances reduction of food products. Furthermore, the advantages, disadvantages and limitations of food irradiation are analyzed. It is concluded that food irradiation is a safety tool to reduce the allergenicity of food effectively, with high nutritional value and long shelf-life, making it a competitive alternative technology to traditional techniques such as heating treatments. Of note, a combination of irradiation with additional processing may be a trend for food irradiation.

A Systematic Review of Food Allergy: Nanobiosensor and Food Allergen Detection

Several individuals will experience accidental exposure to an allergen. In this sense, the industry has invested in the processes of removing allergenic compounds in food. However, accidental exposure to allergenic proteins can result from allergenic substances not specified on labels. Analysis of allergenic foods is involved in methods based on immunological, genetic, and mass spectrometry. The traditional methods have some limitations, such as high cost. In recent years, biosensor and nanoparticles combined have emerged as sensitive, selective, low-cost, and time-consuming techniques that can replace classic techniques. Nevertheless, each nanomaterial has shown a different potential to specific allergens or classes. This review used Preferred Reporting Items for Systematic Reviews and the Meta-Analysis guidelines (PRISMA) to approach these issues. A total of 104 articles were retrieved from a standardized search on three databases (PubMed, Scopus and Web of Science). The systematic review article is organized by the category of allergen detection and nanoparticle detection. This review addresses the relevant biosensors and nanoparticles as gold, carbon, graphene, quantum dots to allergen protein detection. Among the selected articles it was possible to notice a greater potential application on the allergic proteins Ah, in peanuts and gold nanoparticle-base as a biosensor. We envision that in our review, the association between biosensor and nanoparticles has shown promise in the analysis of allergenic proteins present in different food samples.

Effects of gamma irradiation on tropomyosin allergen, proximate composition and mineral elements in giant freshwater prawn (Macrobrachium rosenbergii)

Effects of food irradiation on allergen and nutritional composition of giant freshwater prawn are not well documented. Thus, this study aimed to investigate the effects of gamma irradiation on tropomyosin allergen, proximate composition, and mineral elements in Macrobrachium rosenbergii. In this study, prawn was peeled, cut into small pieces, vacuum packaged and gamma irradiated at 0, 5, 7, 10 and 15 kGy with a dose rate of 0.5 kGy/h using cobalt-60 as the source, subsequently determined the level of tropomyosin, proximate composition and mineral elements respectively. The results showed that band density of tropomyosin irradiated at 10 and 15 kGy is markedly decreased. Proximate analysis revealed that moisture, protein, and carbohydrate content were significantly different as compared with non-irradiated prawn. Meanwhile, gamma irradiated M. rosenbergii at 15 kGy was observed to be significantly higher in nickel and zinc than the non-irradiated prawn. The findings provide a new information that food irradiation may affect the tropomyosin allergen, proximate composition and mineral elements of the prawn.

Characterization of the potential allergenicity of irradiated bovine α-lactalbumin in a BALB/c mouse model

Bovine α-lactalbumin (ALA) is a known food allergen present in milk to induce anaphylaxis. A previous study demonstrated that irradiated ALA (iALA) decreased the IgE-binding properties and weakened the degranulation capacity of basophils in vitro. The present study aimed to further assess the potential allergenicity of iALA in vivo in a BALB/c mouse model. The mice (n = 10/group) were intragastrically sensitized and orally challenged with either iALA or ALA using cholera toxin as adjuvant. In contrast to the ALA group, the iALA group did not show anaphylactic shock symptoms. A tendency toward decreased serum allergen-specific IgG/IgG₁/IgE levels, plasma histamine levels and mast cell protease-1 (mMCP-1) concentrations in the iALA group were also observed, accompanied by a decrease in Th2-related cytokine levels and an increase of IFN-γ production in spleen cell cultures. Moreover, the peritoneal mast cell surface expression of FcεRI and peripheral blood basophil CD200R⁺ expression were decreased by 64.3% and 35.19%, respectively. Conversely, the percentage of CD4⁺CD25⁺Foxp3⁺ regulatory T cells increased in the iALA group. All of these findings indicated that iALA induces a shift toward the Th1 response, which ultimately reduces its potential allergenicity.

Potential allergenicity response to structural modification of irradiated bovine α-lactalbumin

Bovine α-lactalbumin (α-La) is a major food allergen found in milk and is characterized by high conformational stability because of its four disulfide bridges and being calcium bound.

Effect of gamma irradiation on mistletoe (Viscum album) lectin-mediated toxicity and immunomodulatory activity

This study evaluated the effect of gamma irradiation on the reduction of the toxicity of mistletoe lectin using both in vitro and in vivo models. To extract the lectin from mistletoe, an (NH4)2SO4 precipitation method was employed and the precipitant purified using a Sepharose 4B column to obtain the pure lectin fraction. Purified lectin was then gamma-irradiated at doses of 0, 5, 10, 15, and 20 kGy, or heated at 100 °C for 30 min. Toxic effects of non-irradiated, irradiated, and heat-treated lectins were tested using hemagglutination assays, cytotoxicity assays, hepatotoxicity, and a mouse survival test and immunological response was tested using cytokine production activity. Hemagglutination of lectin was remarkably decreased (P < 0.05) by irradiation at doses exceeding 10 kGy and with heat treatment. However, lectin irradiated with 5 kGy maintained its hemagglutination activity. The cytotoxicity of lectin was decreased by irradiation at doses over 5 kGy and with heat treatment. In experiments using mouse model, glutamate oxaloacetate transaminase (GOT) and glutamic pyruvic transaminase (GPT) levels were decreased in the group treated with the 5 kGy irradiated and heat-treated lectins as compared to the intact lectin, and it was also shown that 5 kGy irradiated and heat-treated lectins did not cause damage in liver tissue or mortality. In the result of immunological response, tumor necrosis factor (TNF-α) and interleukin (IL-6) levels were significantly (P < 0.05) increased in the 5 kGy gamma-irradiated lectin treated group. These results indicate that 5 kGy irradiated lectin still maintained the immunological response with reduction of toxicity. Therefore, gamma-irradiation may be an effective method for reducing the toxicity of lectin maintaining the immune response.

A review on the beneficial aspects of food processing

The manuscript reviews beneficial aspects of food processing with main focus on cooking/heat treatment, including other food-processing techniques (e.g. fermentation). Benefits of thermal processing include inactivation of food-borne pathogens, natural toxins or other detrimental constituents, prolongation of shelf-life, improved digestibility and bioavailability of nutrients, improved palatability, taste, texture and flavour and enhanced functional properties, including augmented antioxidants and other defense reactivity or increased antimicrobial effectiveness. Thermal processing can bring some unintentional undesired consequences, such as losses of certain nutrients, formation of toxic compounds (acrylamide, furan or acrolein), or of compounds with negative effects on flavour perception, texture or colour. Heat treatment of foods needs to be optimized in order to promote beneficial effects and to counteract, to the best possible, undesired effects. This may be achieved more effectively/sustainably by consistent fine-tuning of technological processes rather than within ordinary household cooking conditions. The most important identified points for further study are information on processed foods to be considered in epidemiological work, databases should be built to estimate the intake of compounds from processed foods, translation of in-vitro results to in-vivo relevance for human health should be worked on, thermal and non-thermal processes should be optimized by application of kinetic principles.

Microbial population, physicochemical quality, and allergenicity of molluscs and shrimp treated with cobalt-60 gamma radiation

Frozen molluscs (squid, octopuses, and cuttlefish) and crustaceans (shrimp) were irradiated using a cobalt-60 gamma source, at different doses, in order to investigate the effects of gamma radiation on their microbial population, organoleptic characteristics, lipid profile, and tropomyosin content. Irradiation of shrimp and squid with either 2.5 or 4.7 kGy reduced mesophilic bacteria contamination to low or nondetectable levels, respectively, whereas irradiation of octopus and cuttlefish with the same doses reduced the bacterial population. Irradiation treatment had no significant (P > 0.05) effect on the total lipid content and the major detected classes of polar and neutral lipids, whereas it significantly (P < 0.05) increased the contents of neutral lipids in octopus mantle and in shrimp muscle and cephalothorax samples. The total fatty acid content and the omega-3: omega-6 fatty acid ration was not affected. A dose-dependent significant (P < 0.05) decrease in the ratio of polyunsaturated fatty acids:saturated fatty acids was observed. With the increase in radiation dose, redness (a) and yellowness (b) values showed a variation, whereas the lightness (L) value was significantly (P < 0.05) decreased in mollusc mantles and shrimp muscle and increased in shrimp cephalothorax. The total of color changes ( delta E) increased (P < 0.05) as the dose increased. Significant (P < 0.05) changes in textural properties were observed with radiation treatment in octopus tentacles and in squid and cuttlefish mantle. The amount of tropomyosin, which is the major mollusc and crustacean allergen in the irradiated organisms, was reduced by gamma radiation, depending on the dose.

Effect of high intensity ultrasound on the allergenicity of shrimp

The tropomyosin fraction of shrimp proteins is potentially responsible for allergic reaction in individuals with genetic predisposition to allergy. However, there are no efficient and safe methods to reduce its allergenicity. High intensity ultrasound is known to change the structure of proteins. This study is aimed at assessing high intensity ultrasound's effect on the allergenicity of shrimp allergen. Shrimp and purified shrimp allergen were treated with high intensity ultrasound for 30-180 min. Extracts of treated samples were analyzed by enzyme-linked immunosorbent assay (ELISA) with pool serum of shrimp allergy patients and polyclonal anti-allergen antibodies and by immunoblotting after polyacrylamide gel electrophoresis. Shrimp treated with high intensity ultrasound showed a decrease in allergenicity measured with ELISA. A linear relationship between the immune response induced by treated shrimp allergen and the applied treatment time was observed. The decrease in allergenicity was confirmed by immunoblot assays with shrimp allergic patients serum. Allergenicity of shrimp allergen extracted from treated shrimp was higher than that of purified shrimp allergen with the same treatment time. Gel-filtration HPLC was applied for analysis of shrimp allergen after treatment with high intensity ultrasound. Some fractions were appeared with increasing treatment time. The results suggested that high intensity ultrasound could be used to reduce the allergenicity of shrimp.

Change of an egg allergen in a white layer cake containing gamma-irradiated egg white

This study was conducted to evaluate the reduction of an egg allergen in a cake containing gamma-irradiated egg white. A white layer cake was manufactured by a commercial formula with 10- or 20-kGy-irradiated egg white. Enzyme-linked immunosorbent assays (ELISAs) with immunoglobulin (Ig) E from egg-allergic patients and with rabbit anti-ovalbumin IgG were used to identify and quantify ovalbumin (OVA) in the samples. Concentrations of native OVA detected by IgE and IgG in the control were 432.88 and 375.46 microg/g sample, respectively. However, native OVA in samples with 10- and 20-kGy-irradiated egg white was detected at low concentrations (14.27 and 8.78 microg/g, respectively) by IgE (P < 0.05); IgG recognized OVA more often in 10- and 20-kGy samples than in controls. Conformational cleavage of OVA by irradiation could explain the IgG result. The results appear to suggest that irradiating egg white might reduce its allergenicity, which could be used in the production of baked goods of reduced allergenicity.