Food Analysis Technique - Assignment Example

Microbiology, Food Analysis Technique (College) Food Analysis Techniques Food analysis is the study, development and application of different analytical techniques by characterization of food constituents to ensure food safety and quality. This analysis of food involves critical examination of the composition of food, its structure, its physiochemical properties and human responses towards its composition. The various analytical methods used are relevant for quality control, nutritional labeling, research and development of new food products or improvement of existing ones and most importantly for food safety. This paper will focus on the modern analytical techniques used in food analysis to ensure food safety. Food safety is indispensable as it affects the health of consumers and it would be injurious to the manufacturers’ credibility if their products are found to be harmful or toxic. Unsafe food products refer to those that may have harmful microorganisms, for example bacteria or fungi, toxic chemicals like pesticides or herbicides or any foreign matter like metal, wood or plastic. Food safety is ensured using different analytical techniques that are discussed below. This techniques selected are ensured to be accurate, have great precision (reproducibility and repeatability), sensitivity and practicability under normal laboratory conditions. They are usually classified according to their working principle. Spectroscopic techniques is one of the food analysis techniques used. This techniques include mass spectrometry, infrared, nuclear magnetic resonance and atomic spectroscopy. This techniques are founded on the principle that molecules and atoms are able to interact with electromagnetic radiation. They provide information through detection of wavelength or frequency in the emitted or absorbed energy spectrum. These techniques are efficient in food analysis because they give direct measurement of food, are fast, do not use toxic solvents or reactants, can detect several compounds simultaneously and are not destructive or non-invasive. Spectroscopic techniques provide information about food properties like its molecular composition, structure dynamics and interactions. To understand how these spectroscopic techniques work, a better understanding of distribution of energy in atoms and molecules, characteristic of electromagnetic radiation and the interaction electromagnetic radiation with these molecules and atoms is required. Molecular species contain a unique set of energy levels depending on its molecular and atomic structure. Electromagnetic waves are particles of energy moving through space and these waves consist of oscillating electric and magnetic fields. The electromagnetic waves propagate through the food material and the atoms and molecules absorb energy and move to their excited state. These energy is then emitted since the molecules exist in this state for a short time. Spectroscopic technique works by depending on the energetic transitions involved (electronic, vibration and nuclear), the nature of radiative process (absorption or emission) and the nature of the food matrix (absorbing or non-absorbing). These factors determine the wavelength of electromagnetic radiation used which is measured by the analytical instruments being used. Nowadays, the most used spectroscopic technique used is infrared. This technique is relevant because it is able to identify transgenics which may have health effects. For instance, a genetically modified potato may have excessive levels of naturally occurring toxins which will cause poisoning to consumers. It is also important in measuring bioactive compounds in foods. Bioactive compounds are non-essential to human beings, however some of them like flavonoids have been found to influence the effect of drugs. Tandem mass spectrometry is important in identification and quantification of analytes mainly contaminants and analysis of pesticides and their metabolites in water and food matrices. For instance pesticides applied on vegetable or fruits affect the neurological system such as memory loss, reduced visual ability and loss of co-ordination when exposed to human beings through the skin or ingestion. Hyphenated techniques is another analytical technique for food analysis. (Malik, Blasco and Picó, 2010) state that this technique combines at least two analytical techniques for instance liquid chromatography coupled to tandem spectrometry or mass spectrometry. There are a wide variety of application of this technique in food analysis. For instance this technique enables analyzing of antimicrobial residues in food of animal origin. This is important because beef, for instance may have several residues like toxic metals such as lead, cadmium and mercury, pesticides, arsenics or polychlorinated biphenyls. This substances are harmful when exposed to consumers. This technique also enables identification of food allergens and clenbuterol residues in food. (Brambilla 1997) conducted a study about whether clenbuterol residues in the veal liver cause human poisoning. Their findings were that clenbuterol caused headaches, tremors and tachycardia in human beings. Other hyphenated techniques such as gas chromatography coupled with mass spectrometry or electrophoresis coupled with mass spectrometry were useful in identifying food contaminants. Biological techniques is also an analytical technique used in analysis of food. They employ living organisms, enzymes, antibodies or DNA to analyze food. (Xu and Ying, 2011) elucidate that DNA and molecular based techniques have enabled detection of salmonella in food and the microbial composition in different foods. This is relevant because salmonella ingestion will cause diseases like gastroenteritis, food poisoning and typhoid fever. Other microbial organisms will also cause infection to human beings. Biosensors is another example of biological techniques which is composed of biological recognition elements such as enzymes, microbes and antibodies coupled with physical or chemical transducers. This analytical technique converts chemical signals into an electrical response. Biosensors are able to detect toxins, antimicrobial residues and pesticides in food. Some foods contain chemicals and highly processed ingredients that are toxic to human beings. For instance hydrogenated vegetable oils are toxic because of Trans fats. Other developments under these technique is the use of peptide nucleic acid (PNA) based technologies to analyze drug residues in food and food products and to characterize food allergens. Microarray technique is a technique that allows expansion of the DNA significantly in terms of number of DNA that can be analyzed simultaneously. It is used in food analysis by enabling microbial analysis of pathogens in food substances in a single array assay. It is relevant because it detects infectious microbial pathogens in food so that they can be eliminated and ensure the food product is safe. Histology is another analytical technique useful in food analysis. This technique is uses a microscope to observe the morphology of a tissue. Environmental toxins and veterinary drugs have an effect on the morphology of a tissue and this can be observed under the microscope. This technique is relevant as it enables detection environmental contaminants, antimicrobial residues and mycotoxins in foods such as some edible mushrooms. Food omics is a new discipline that is also an analytical technique for food analysis. It is the study of compound profiling and biomarker detection through application of advanced “omics” technologies that incorporate mass spectrometry based measurements. This technique is relevant as it enables detection of mycotoxins in foods. Reference List Brambilla, G. (1997). Food poisoning following consumption of clenbuterol-treated veal in Italy. JAMA: The Journal of the American Medical Association, 278(8), pp.635b-635. Malik, A., Blasco, C. and Picó, Y. (2010). Liquid chromatography–mass spectrometry in food safety. Journal of Chromatography A, 1217(25), pp.4018-4040. Xu, X. and Ying, Y. (2011). Microbial Biosensors for Environmental Monitoring and Food Analysis. Food Reviews International, 27(3), pp.300-329. Read More