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

Abstract

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.

Bovine Milk Allergens: A Comprehensive Review

“…Biosensors are considered emerging tools for allergen detection, since they are fast, repeatable, and highly sensitive approaches with great potential for full automation. In brief, biosensors are based on the direct recognition of a biological interaction between a receptor (antibody or probes) and a target molecule (protein or DNA) by means of a transducer that produces a measurable signal (Schubert‐Ullrich and others ; Prado and others ; Costa and others ). Several studies have been performed using SPR immunosensors to detect milk allergens in different food matrices, reaching sensitivities of 1 ng/L to 0.12 mg/mL (Indyk and Filonzi ; Hiep and others ; Indyk ; Billakanti and others ; Raz and others ).…”

“…There are 2 main approaches for allergen detection, quantification, and characterization: the bottom‐up approach, where proteins are digested with enzymes, such as trypsin, prior to MS analysis; and the top‐down approach, where the whole proteins are fragmented directly inside the mass spectrometer, avoiding the variable step of protein digestion. The bottom‐up approach is the most commonly used due to the current limited performance of top‐down‐based instruments (Prado and others ).…”

“…Food processing alters the extractability and solubility of allergenic or other marker proteins, which can compromise the good performance of the MS‐based method. However, the advantages of high accuracy, specificity, and multitarget analysis, make the MS‐platforms more widely used for allergen analysis than the classical immunochemical assays (Prado and others ).…”

“…DNA targets might be genes that encode allergenic proteins or other specific sequences, therefore they are considered as indirect markers of the presence of an allergenic ingredient. Most of the published works using DNA‐based methods consist of the amplification of the initial target DNA sequences by PCR with the use of specific primers, responsible for conferring a high specificity level to the assays (Mafra and others ; Prado and others ). The main approaches used for allergen detection are end point PCR, multiplex PCR, real‐time PCR, and PCR‐ELISA, but recently new promising advances have gained much interest, such as real‐time PCR coupled to high‐resolution melting (HRM) analysis, single‐tube nested real‐time PCR, DNA arrays, and genosensors.…”

Nano-Biosensing Platforms for Detection of Cow’s Milk Allergens: An Overview

“…The low concentration of allergens and also food matrices can be a problematic challenge in front of their detection. Most applied analytical approaches for milk allergens detection are: Protein-based methods and DNA-based methods [35,36]. These approaches differentiate in terms of the type of marker used for the allergen detection.…”