Biosensors as Novel Platforms for Detection of Food Pathogens and Allergens

Luminescent Aptamer-Based Bioassays for Sensitive Detection of Food Allergens

The presence of hidden allergens in food products, often due to unintended contamination along the food supply chain (production, transformation, processing, and transport), has raised the urgent need for rapid and reliable analytical methods for detecting trace levels of such species in food products. Indeed, food allergens represent a high-risk factor for allergic subjects due to potentially life-threatening adverse reactions. Portable biosensors based on immunoassays have already been developed as rapid, sensitive, selective, and low-cost analytical platforms that can replace analyses with traditional bench-top instrumentation. Recently, aptamers have attracted great interest as alternative biorecognition molecules for bioassays, since they can bind a variety of targets with high specificity and selectivity, and they enable the development of assays exploiting a variety of transduction and detection technologies. In particular, aptasensors based on luminescence detection have been proposed, taking advantage of the development of ultrasensitive tracers and enhancers. This review aims to summarize and discuss recent efforts in the field of food allergen analysis using aptamer-based bioassays with luminescence detection.

Silver Cluster Interactions with Tyrosine: Towards Amino Acid Detection

Tyrosine (Tyr) is involved in the synthesis of neurotransmitters, catecholamines, thyroid hormones, etc. Multiple pathologies are associated with impaired Tyr metabolism. Silver nanoclusters (Ag NCs) can be applied for colorimetric, fluorescent, and surface-enhanced Raman spectroscopy (SERS) detection of Tyr. However, one should understand the theoretical basics of interactions between Tyr and Ag NCs. Thereby, we calculated the binding energy (Eb) between Tyr and Agnq (n = 1-8; q = 0-2) NCs using the density functional theory (DFT) to find the most stable complexes. Since Ag NCs are synthesized on Tyr in an aqueous solution at pH 12.5, we studied Tyr-1, semiquinone (SemiQ-1), and Tyr-2. Ag32+ and Ag5+ had the highest Eb. The absorption spectrum of Tyr-2 significantly red-shifts with the attachment of Ag32+, which is prospective for colorimetric Tyr detection. Ag32+ interacts with all functional groups of SemiQ-1 (phenolate, amino group, and carboxylate), which makes detection of Tyr possible due to band emergence at 1324 cm-1 in the vibrational spectrum. The ground state charge transfer between Ag and carboxylate determines the band emergence at 1661 cm-1 in the Raman spectrum of the SemiQ-1-Ag32+ complex. Thus, the prospects of Tyr detection using silver nanoclusters were demonstrated.

Novel Nondestructive Biosensors for the Food Industry

An increasing number of foodborne outbreaks, growing consumer desire for healthier products, and surging numbers of food allergy cases necessitate strict handling and screening of foods at every step of the food supply chain. Current standard procedures for detecting food toxins, contaminants, allergens, and pathogens require costly analytical devices, skilled technicians, and long sample preparation times. These challenges can be overcome with the use of biosensors because they provide accurate, rapid, selective, qualitative, and quantitative detection of analytes. Their ease of use, low-cost production, portability, and nondestructive measurement techniques also enable on-site detection of analytes. For this reason, biosensors find many applications in food safety and quality assessments. The detection mechanisms of biosensors can be varied with the use of different transducers, such as optical, electrochemical, or mechanical. These options provide a more appropriate selection of the biosensors for the intended use. In this review, recent studies focusing on the fabrication of biosensors for food safety or food quality purposes are summarized. To differentiate the detection mechanisms, the review is divided into sections based on the transducer type used.

Emerging graphene-based sensors for the detection of food adulterants and toxicants - A review

The detection of food adulterants and toxicants can prevent a large variety of adverse health conditions for the global population. Through the process of rapid sensing enabled by deploying novel and robust sensors, the food industry can assist in the detection of adulterants and toxicants at trace levels. Sensor platforms which exploit graphene-based nanomaterials satisfy this requirement due to outstanding electrical, optical and thermal properties. The materials' facile conjugation with linkers and biomolecules along with the option for further enhancement using nanoparticles results in highly sensitive and selective sensing characteristics. This review highlights novel applications of graphene derivatives for detection covering three important approaches; optical, electrical (field-effect) and electrochemical sensing. Suitable graphene-based sensors for portable devices as point-of-need platforms are also presented. The future scope of these sensors is discussed to showcase how these emerging techniques will disrupt the food detection sector for years to come.

Freshness Monitoring of Packaged Vegetables

Smart packaging is an emerging technology that has a great potential in solving conventional food packaging problems and in meeting the evolving packaged vegetables market needs. The advantages of using such a system lies in extending the shelf life of products, ensuring the safety and the compliance of these packages while reducing the food waste; hence, lessening the negative environmental impacts. Many new concepts were developed to serve this purpose, especially in the meat and fish industry with less focus on fruits and vegetables. However, making use of these evolving technologies in packaging of vegetables will yield in many positive outcomes. In this review, we discuss the new technologies and approaches used, or have the potential to be used, in smart packaging of vegetables. We describe the technical aspects and the commercial applications of the techniques used to monitor the quality and the freshness of vegetables. Factors affecting the freshness and the spoilage of vegetables are summarized. Then, some of the technologies used in smart packaging such as sensors, indicators, and data carriers that are integrated with sensors, to monitor and provide a dynamic output about the quality and safety of the packaged produce are discussed. Comparison between various intelligent systems is provided followed by a brief review of active packaging systems. Finally, challenges, legal aspects, and limitations facing this smart packaging industry are discussed together with outlook and future improvements.

An Overview of the Applications of Nanomaterials and Nanodevices in the Food Industry

The efficient progress in nanotechnology has transformed many aspects of food science and the food industry with enhanced investment and market share. Recent advances in nanomaterials and nanodevices such as nanosensors, nano-emulsions, nanopesticides or nanocapsules are intended to bring about innovative applications in the food industry. In this review, the current applications of nanotechnology for packaging, processing, and the enhancement of the nutritional value and shelf life of foods are targeted. In addition, the functionality and applicability of food-related nanotechnologies are also highlighted and critically discussed in order to provide an insight into the development and evaluation of the safety of nanotechnology in the food industry.

Food packaging and nanotechnology: safeguarding consumer health and safety

Purpose

Nanotechnology as an emerging area if adequately harnessed could revolutionise food packaging and food processing industry worldwide. Although several benefits of nano-materials or particles in food packaging have been suggested, potential risks and health hazards of nano-materials or particles are possible as a result of migration of their particles into food materials. The purpose of this review therefore assessed nanotechnology and its applications in food packaging, consumer acceptability of nano-packaged foods and potential hazards and safety issues in nano-packaged foods.

Design/methodology/approach

This review takes a critical assessment of previous literature on nanotechnology and its impact on food packaging, consumer health and safety.

Findings

Applications of nanotechnology in food packaging could be divided into three main divisions: improved packaging, which involves mixing nano-materials into polymers matrix to improve temperature, humidity and gas barrier resistance of the packaging materials. Active packaging deals with direct interaction between nano-materials used for packaging and the food to protect it as anti-microbial or oxygen or ultra violet scavengers. Smart packaging could be used to sense biochemical or microbial changes in foods, as well as a tracker for food safety, to prevent food counterfeit and adulteration. The review also discussed bio-based food packaging which is biodegradable. Bio-based packaging could serve as veritable alternative to conventional packaging which is non-degradable plastic polymers which are not environmental friendly and could pose a threat to the environment. However, bio-based packaging could reduce material waste, elongate shelf life and enhance food quality. However, several challenges are envisaged in the use of nano-materials in food packaging due to knowledge gaps, possible interaction with food products and possible health risks that could result from the nano-materials used for food packaging.

Originality/value

The increase in growth and utilisation of nanotechnology signifies wide use of nano-materials especially in the food sector with arrays of potential benefits in the areas of food safety and quality, micronutrients and bioactive ingredients delivery, food processing and in packaging Active studies are being carried out to develop innovative packages such as smart, intelligent and active food packaging to enhance effective and efficient packaging, as well as balanced environmental issues. This review looks at the future of nano-packaged foodsvis-à-visthe roles played by stakeholders such as governments, regulatory agencies and manufacturers in looking into consumer health and safety issues related to the application of nano-materials in food packaging.

Prospects of using nanotechnology for food preservation, safety, and security

The rapid development of nanotechnology has transformed many domains of food science, especially those that involve the processing, packaging, storage, transportation, functionality, and other safety aspects of food. A wide range of nanostructured materials (NSMs), from inorganic metal, metal oxides, and their nanocomposites to nano-organic materials with bioactive agents, has been applied to the food industry. Despite the huge benefits nanotechnology has to offer, there are emerging concerns regarding the use of nanotechnology, as the accumulation of NSMs in human bodies and in the environment can cause several health and safety hazards. Therefore, safety and health concerns as well as regulatory policies must be considered while manufacturing, processing, intelligently and actively packaging, and consuming nano-processed food products. This review aims to provide a basic understanding regarding the applications of nanotechnology in the food packaging and processing industries and to identify the future prospects and potential risks associated with the use of NSMs.

Biosensors for rapid and sensitive detection of Staphylococcus aureus in food

Foodborne illness outbreaks caused by the consumption of food contaminated with harmful bacteria has drastically increased in the past decades. Therefore, detection of harmful bacteria in the food has become an important factor for the recognition and prevention of problems associated with food safety and public health. Staphylococcus aureus is one of the most commonly isolated foodborne pathogen and it is considered as a major cause of foodborne illnesses worldwide. A number of different methods have been developed for the detection and identification of S. aureus in food samples. However, some of these methods are laborious and time-consuming and are not suitable for on-site applications. Therefore, it is highly important to develop rapid and more approachable detection methods. In the last decade, biosensors have gained popularity as an attractive alternative method and now considered as one of most rapid and on-site applicable methods. An overview of the biosensor based methods used for the detection of S. aureus is presented herein. This review focuses on the state-of-the-art biosensor methods towards the detection and quantification of S. aureus, and discusses the most commonly used biosensor methods based on the transducing mode, such as electrochemical, optical, and mass-based biosensors.

Ensuring food safety using aptamer based assays: Electroanalytical approach

Aptamers, are being increasingly employed as favorable receptors for constructing highly sensitive biosensors, for their remarkable affinities towards certain targets including a wide scope of biological or chemical substances, and their superiority over other biologic receptors. The selectivity and affinity of the aptamers have been integrated with the wise design of the assay, applying suitable modifications, such as nanomaterials on the electrode surface, employing oligonucleotide-specific amplification strategies or, their combinations. After successful performance of the electrochemical aptasensors for biomedical applications, the food sector with its direct implication for human health, which demands rapid and sensitive and economic analytical solutions for determination of health threatening contaminants in all stages of production process, is the next field of research for developing efficient electrochemical aptasensors. The aim of this review is to categorize and introduce food hazards and summarize the recent electrochemical aptasensors that have been developed to address these contaminants.

Nanotechnology in food science: Functionality, applicability, and safety assessment

Rapid development of nanotechnology is expected to transform many areas of food science and food industry with increasing investment and market share. In this article, current applications of nanotechnology in food systems are briefly reviewed. Functionality and applicability of food-related nanotechnology are highlighted in order to provide a comprehensive view on the development and safety assessment of nanotechnology in the food industry. While food nanotechnology offers great potential benefits, there are emerging concerns arising from its novel physicochemical properties. Therefore, the safety concerns and regulatory policies on its manufacturing, processing, packaging, and consumption are briefly addressed. At the end of this article, the perspectives of nanotechnology in active and intelligent packaging applications are highlighted.

Robust and direct electrochemical sensing of arsenic using zirconia nanocubes

The presence of heavy metal ions in the environment and in food items can severely harm human health.