不同食品加工方式对食物过敏原蛋白的影响

食物过敏是一个全球化的公共卫生和食品安全问题,通过食品加工来消除或减轻食物过敏原蛋白的致敏性,一直是食品科学领域的研究热点。文章介绍了3种热加工技术(湿热加工、干热加工、微波加工)和6种非热加工技术(超高压技术、超声波技术、低温等离子体技术、辐照技术、微生物发酵技术和酶交联技术)对食物过敏原蛋白致敏性的影响,期望为研发低致敏性或脱敏食品提供一定的借鉴和参考,以破解食物过敏人群膳食受限的困扰。     

热处理对食物致敏性的影响及其体外细胞学评价

综述了热加工处理对典型食物过敏原致敏性的影响,重点介绍了体外细胞学评价方法在评价食物过敏原致敏性变化方面的一些研究进展。人们生活方式和环境的改变,以及日常食物丰富所致过敏诱发因素的增加,食物过敏发生比例大幅提高,食品过敏问题已成为目前国内外食品安全研究的热点之一。食品热加工可以改变食物过敏原的蛋白表位结构、聚合特性以及过敏原诱发淋巴细胞释放细胞因子的特性。由于食品基质、配料和处理过程的差异,加工过程中食品致敏性的变化尚无普遍规律可循。通过对典型食物过敏原的分离纯化、分子鉴定,可以追踪过敏原组分在食物加工过程中的改变规律。目前过敏效应分子IgE抗体的水平变化常常被作为致敏性评价的指标,酶联免疫分析和免疫印迹试验是常用的测定手段。然而,对于过敏反应阶段由IgE抗体与效应细胞上FcεR受体之间的结合引发系列炎症反应的部分,则无法通过这些方法进行判断。全面评价食物过敏原的致敏效应不但需要监测IgE抗体水平,也需要监测效应细胞致敏程度,以及释放的细胞因子水平。     

蟹类水产品过敏原及其致敏性消减技术研究进展

蟹类是我国重要的经济水产品,也是诱发过敏反应的主要食物之一。因此,了解蟹类水产品过敏原种类及抗原表位,探究有效的蟹类致敏性消减技术等极为迫切。阐明蟹类水产品过敏原及其抗原表位是消减其致敏性的重要前提,概述了国内外分离鉴定的蟹类水产品过敏原,包括原肌球蛋白、精氨酸激酶、肌质钙结合蛋白、磷酸丙糖异构酶、细丝蛋白c等;总结了利用生物信息学技术、噬菌体展示技术、一珠一化合物技术等定位分析蟹类水产品过敏原的线性表位和构象表位概况。比较了辐照技术、超声技术、美拉德反应技术、酶法交联技术、微生物发酵技术等现代加工处理方法,或修饰过敏原抗原表位或破坏过敏原蛋白质结构,从而消减蟹类水产品过敏原致敏性。着重分析了蟹类水产品过敏原的未来研究趋势,提出蟹类水产品过敏原结构与致敏性的构效关系解析是该领域的研究难点;对比了物理法、化学法、生物法在蟹类水产品致敏性消减方面的优缺点,提出未来重点发展复合加工处理方式,以便更大程度地降低过敏原致敏性,从而为低致敏性的蟹类食品或生物制品的开发提供技术依据。     

加工对食物过敏蛋白致敏性影响的研究进展

食物过敏已成为世界关注的重大公共卫生和食品安全问题。文章综述近年来国内外有关加工处理(热加工和非热加工)对食物过敏蛋白致敏性的影响:加工方式、处理强度等均会影响过敏蛋白的分子特性,从而导致其或增敏、或脱敏、或不变;加工虽不能完全消除过敏原的致敏潜力,但可通过加工方式和加工参数的选择使其致敏潜力最小化。通过选择合适的食品加工方式控制食物过敏原,在不改变食物营养价值的条件下,获得脱敏性食物,满足食物易敏人群的正常饮食需求,为消费者提供安全食品,是现代食品工业的重要任务之一。     

酶改性对食物蛋白过敏原性的影响

酶法改性蛋白技术主要包括酶水解和酶交联方法,它可以改变蛋白质的结构和功能特性,已广泛用于食品加工。酶水解,包括胃蛋白酶、胰蛋白酶、木瓜蛋白酶、碱性蛋白酶、糜蛋白酶,可以水解食物蛋白表面的过敏原表位,从而降低其过敏原性;酶交联,包括转谷酰胺酶、过氧化物酶、多酚氧化酶等,可以通过交联反应促使过敏原蛋白聚合而使其过敏原表位包裹在内部,因而也可以降低食物的过敏原性。总之,酶改性是降低食物蛋白过敏原性的一种有效方法,值得深入研究。     

芝麻过敏原及其致敏性消减技术研究进展

芝麻是新的“8大类”过敏食物之一,芝麻过敏反应由于其潜在危害性及其日益上升的发病率而越来越引起全世界的普遍重视,因此研究芝麻致敏性消减技术在保障食品安全方面具有重要意义。概述了芝麻主要过敏原(Ses i 1～Ses i 7)的结构和免疫特性,及其致敏性消减技术原理和研究进展;已报道的芝麻过敏原有7种,属于2S白蛋白、7S类豌豆球蛋白、油质蛋白和11S球蛋白,其中11S球蛋白和2S白蛋白是主要的过敏原蛋白。利用热加工技术消减芝麻致敏性,主要通过煮沸、微波、烘焙等工艺引起过敏原的解聚、变性进而破坏致敏表位;高压、辐照、发酵、酶解等非热加工技术通过氢键、疏水键等化学键的变化、多肽链的断裂引起蛋白结构变化,从而掩盖或直接降解致敏表位。另外,结合其他食品过敏原,对芝麻过敏原的潜在消减技术,包括脉冲电场、冷等离子体、超声波、脉冲光、糖基化改性和复合加工技术等进行了阐述分析。未来需要进一步研究芝麻不同过敏原的致敏表位、不同加工工艺对过敏原结构及致敏性影响、开展血清学、细胞和动物模型等致敏性评价等,以明确芝麻致敏性消减的主要机制,以期为生产低敏或脱敏芝麻产品奠定理论依据与科学指导。     

热加工与非热加工技术对水产品致敏性的影响研究进展

我国作为水产养殖和消费总量第一大国,水产品引发的过敏问题越来越受到关注,近些年来,因食用水产品而导致的过敏事件日益增多。该研究综述了近年来热加工技术（蒸、煮、高温压力）、非热加工技术（超高压、低温等离子体、超声波和辐照）以及两种加工技术联用对水产品过敏原消减的研究,指出热加工技术主要通过使蛋白质变性来消减过敏原的致敏性,非热加工技术则通过掩盖或破坏过敏原抗原表位来消减过敏原致敏性,为低致敏性水产品开发提供了重要基础和技术参考。不断探究过敏原诱导过敏反应发生的机理,加快推进低致敏性水产品加工技术在实际生产中的应用,有利于控制和降低水产品过敏所带来的风险。     

基于生物酶解法的牛乳蛋白脱敏技术研究进展

牛乳是婴幼儿主要食物蛋白来源,但也是引起食物过敏的八大类食物之一,研究生产低致敏乳制品对牛乳过敏者具有重要意义.目前,生物酶法是研发低致敏乳制品的主要技术途径.本文详细列举了牛乳过敏蛋白及其能够被识别的致敏表位,介绍了应用生物酶法处理得到低抗原性牛乳蛋白水解产物的技术及其作用效果,并提出了一些对后续研究的思考,为低致敏...     

甲壳类水产食物致敏原及其分子结构的研究进展

甲壳类水产品是亚洲地区最主要的致敏食物。食物过敏主要由摄入的食品致敏原引起,而食物致敏原的结构不仅与抗原表位的形成有关,也决定了其在食品加工和体内消化过程的稳定性。本文针对甲壳类水产品,首先阐述了甲壳类水产食物过敏及致敏原的研究进展;进一步对甲壳类水产食物致敏原的分子结构及其与致敏性的构效关系展开论述,并基于此提出了致敏原脱敏策略。目前已鉴定的甲壳类水产食物致敏原大部分属于肌动蛋白结合蛋白、磷酸原激酶和EF手型钙离子结合蛋白3个家族。针对不同蛋白质家族致敏原的结构特点,通过食品加工技术消减致敏性或利用分子生物学手段获得低致敏性衍生物都是防控食物过敏的重要途径。但甲壳类水产食物致敏原的结构信息有待完善,其与致敏性的构效关系也仍是未来致敏原研究的重要方向。本文综合阐述了甲壳类水产食物致敏原结构特性及其与致敏性的构效关系,以期为甲壳类水产食物致敏原的系统研究和食品脱敏方法的建立提供思路。     

水产品过敏原消减技术研究进展

水产品因其营养丰富,越来越受消费者喜爱。近年来,随着水产品产量和消费量逐年增加,水产品引发的食物过敏也日益增多,已经成为一个食品安全问题。随着食品加工技术及生物技术的提高,人们对过敏原性质的研究及过敏原分离纯化方法不断深入,利用食品加工技术降低食物过敏原致敏性越来越受到大家的关注。低致敏性食品是水产品开发的一个重要方向,很多研究学者对如何降低水产品致敏性进行了深入的研究。本文对水产品过敏原消减技术研究进展进行了概述,简单介绍了水产品过敏的现状及主要过敏原,详细介绍了最常用的5种消除方法,分析了低致敏水产品的发展趋势,以期为低致敏性食品开发提供理论指导。     

Altering allergenicity of cow's milk by food processing for applications in infant formula

Cow's milk-based infant formulas have a long tradition in infant nutrition, although some infants are unable to use them due to presence of several known allergens. Various processing methods have been identified capable of reducing cow's milk protein allergenicity including thermal and non-thermal methods and their combinations. Heat treatment and enzymatic hydrolysis have been in production of hypoallergenic infant formulas. However, modulation of allergenic epitopes depends on the extent of heat treatment applied, which consequently may also reduce a nutritional value of these proteins. In addition, enzymatic hydrolysis may not target allergenic epitopes thus allergenicity may persist; however released peptides may have detrimental impact on taste and functional properties of final products. Modulation of allergenicity of milk proteins appears to require a concerted effort to minimize detrimental effects as clinical studies conducted on commercial hypoallergenic formulas demonstrated persistence of allergic symptoms. This article covers traditional and novel processing methods and their impact on reduction of cow's milk allergenicity in milk-based infant formulas.     

致敏大豆蛋白P34及其清除方法的研究进展

大豆作为"八大"过敏食品之一,其过敏患者数量约占食物过敏总人数的25%。如何降低大豆产品的致敏性,保证消费者的安全,已经成为食品安全领域一个热议的话题。大豆中含有多种致敏因子,如Gly-m Bd 30K蛋白、Gly-m Bd 28K蛋白和Gly-m Bd 28K蛋白等。其中Gly-m Bd 30K蛋白作为致敏性最强的过敏原,能被65%的大豆过敏患者血清识别,在几种过敏蛋白中占着较突出的地位。本文综述了Gly-m Bd 30K蛋白的抗原表位、去除方法的研究现状。其中,酶法处理、超高压法、挤压膨化法等降低大豆致敏性的研究已取得了一定的成果,这为进一步提高大豆及其制品的品质质量,保证其在食品工业和畜牧业方面的安全利用提供了科学参考。     

Advanced DNA- and Protein-based Methods for the Detection and Investigation of Food Allergens

Currently, food allergies are an important health concern worldwide. The presence of undeclared allergenic ingredients or the presence of traces of allergens due to contamination during food processing poses a great health risk to sensitized individuals. Therefore, reliable analytical methods are required to detect and identify allergenic ingredients in food products. The present review addresses the recent developments regarding the application of DNA- and protein-based methods for the detection of allergenic ingredients in foods. The fitness-for-purpose of reviewed methodology will be discussed, and future trends will be highlighted. Special attention will be given to the evaluation of the potential of newly developed and promising technologies that can improve the detection and identification of allergenic ingredients in foods, such as the use of biosensors and/or nanomaterials to improve detection limits, specificity, ease of use, or to reduce the time of analysis. Such rapid food allergen test methods are required to facilitate the reliable detection of allergenic ingredients by control laboratories, to give the food industry the means to easily determine whether its product has been subjected to cross-contamination and, simultaneously, to identify how and when this cross-contamination occurred.     

基于蛋白质和DNA的食品过敏原检测技术的研究进展

目前,食品过敏问题已成为全球性的健康问题。在食品加工过程中产生的食品过敏成分或微量过敏原对敏感机体都是巨大的健康威胁。因此,可靠的分析方法是鉴别和检测食品中过敏成分所必需的。该文综述了基于蛋白质和脱氧核糖核酸(DNA)的食品过敏原检测技术的应用及发展,并展望了其未来发展趋势。     

High hydrostatic pressure assisted enzymatic hydrolysis of whey proteins

Whey proteins, due to their high nutritional value, are generally hydrolyzed to reduce the allergenicity and used as ingredients in many special products, such as infant formulae, geriatric products, highly energetic supplements or dietetic foods or in foods produced to prevent nutrition related diseases, like food intolerances and allergies.The aim of this work was to assess the applicability of innovative technologies, such as high hydrostatic pressure (HHP) processes, to assist the enzymatic hydrolysis of target proteins, namely whey protein concentrate (WPC-80), in order to modify their antigenicity. Experiments were carried out to verify the effectiveness of HHP technology to accelerate whey protein hydrolysis reaction with selected enzymes (α-chymotrypsin, bromelain), and to affect the protein allergenic power. To this purpose, different HHP treatments were carried out at several pressure levels (100, 200, 300 and 400 MPa) and the untreated whey protein samples were used as control. A defined enzyme/substrate ratio of 1/10 w/w was used in the experiments, while the treatment time was changed from 0 to 30 min (0, 5, 15, or 30 min).The experimental data demonstrated that High Hydrostatic Pressure (HHP) induced WPC-80 unfolding at the highest value of the pressure applied (400 MPa) as indicated by the higher exposure of free sulfhydryl groups. When HHP was used in combination with enzymatic hydrolysis, the degree of hydrolysis increased not only with the pressure level applied but also with the processing time. These results suggested that, even if the exposure of hidden epitopes upon protein unfolding increased the antigenicity of whey proteins, further peptide bonds cleavage also took place after hydrolysis. This effect could modify whey proteins antigenic sequences, and thus their antigenic power.     

Hydrolysis under high hydrostatic pressure as a means to reduce the binding of beta-lactoglobulin to immunoglobulin E from human sera

Cows' milk allergy is the most frequent food allergy in children, and beta-lactoglobulin (beta-Lg) is a major allergen. Milk-based hypoallergenic ingredients are manufactured by enzymatic hydrolysis, a process that could be improved by the application of high-pressure treatments. This study showed that the treatment of beta-Lg dissolved in buffer with chymotrypsin and trypsin under high pressure for relatively short times accelerated proteolysis by leading to a rapid removal of the intact protein. The rapid proteolysis of the beta-Lg substrate under pressure led to the production, in 20 min, of hydrolysates with lower immunoglobulin (Ig) G binding than those produced in 8 h (chymotrypsin) or 48 h (trypsin) at atmospheric pressure. However, those hydrolysates retained some residual IgE-binding properties that could be traced to the preferential release, during the initial stages of proteolysis, of peptides containing IgE epitopes, such as (Val-41-Lys-60), (Leu-149-Ile-162), and (Ser-21-Arg-40). The formation of these fragments was favored when proteolysis was conducted under high pressure due to the preferential hydrolysis of Arg-40 and Arg-148 by trypsin, and Tyr-42 and Leu-149 by chymotrypsin, all located at the dimer interface of beta-Lg or very close to it. Although our results do not support that trypsin and chymotrypsin under high pressure selectively address the allergenic regions of beta-Lg, it is possible to select the conditions that quickly produce hydrolysates with reduced potential allergenicity that could be used in hypoallergenic foods.     

Peanut Allergy: Characteristics and Approaches for Mitigation

Peanut allergy has garnered significant attention because of the high sensitization rate, increase in allergy, and severity of the reaction. Sufficiently reliable therapies and efficient mitigating techniques to combat peanut allergy are still lacking. Current management relies on avoiding peanuts and nuts and seeds with homologous proteins, although adverse events mostly occur with accidental ingestion. There is a need for hypoallergenic peanut products to protect sensitized individuals and perhaps serve as immunotherapeutic products. Alongside traditional practices of thermal and chemical treatment, novel processing approaches such as high‐pressure processing, pulsed ultraviolet light, high‐intensity ultrasound, irradiation, and pulsed electric field have been performed toward reducing the immunoreactivity of peanut. Covalent and noncovalent chemical modifications to proteins also have the tendency to alter peanut allergenicity. Enzymatic hydrolysis seems to be the most advantageous technique in diminishing the allergenic potential of peanut. Furthermore, the combined processing approach (hurdle technologies) such as enzymatic hydrolysis followed by, or in conjunction with, roasting, high pressure and heat, ultrasound with enzymatic treatment, or germination have shown a significant reduction of peanut immunoreactivity and may emerge as useful techniques in reducing the allergenicity of peanut and other foods. This study represents our current knowledge about the alterations in allergenic properties of peanut via different processing mechanisms as well as evaluating its future potential, geographical based data on increasing sensitization, clinical relevance, eliciting dose, and current management of peanut allergy. Furthermore, the molecular characteristics and clinical relevance of peanut allergens have been discussed.     

Modulation of milk immunogenicity by thermal processing

Bovine milk proteins, apart from provision of essential amino acids, impact on the human immune system. Heat treatments applied in processing of bovine milk directly influence milk protein structure and changes in associated epitopes, altering the immunogenic and antigenic potential of milk proteins, and thus modulating the human immune system in different ways. The severity of some processing technologies impact on important minor proteins that may exert immunomodulatory properties, in such a way as to prevent occurrence of allergies. In this review, heat-induced modifications of milk protein structure, associated changes in epitopes, alteration of immunomodulatory properties of milk and their effects on immunogenic and antigenic potential of milk proteins are discussed. Thermal processing in the dairy industry could be further optimised in a way to preserve and utilise the favourable immunomodulatory properties of milk, in addition to ensuring food safety, eventually making the final dairy product both hygienic and hypoallergenic.