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Food authenticity and quality

Adulterated foods
Now we talk about food authenticity and quality. Determining the authenticity of foods can prevent false description substitution of cheaper ingredients and adulteration as well as incorrect origin labeling. However, food adulteration reports are a growing challenge for food manufacturers because most adulteration are unknown. They are difficult to recognize using the targeted screening methods typically used in food laboratories. In order to protect consumer interests and public health, the food laboratory urgently needs methods that will screen non-targeted food samples for adulterants to provide proof of origin to food samples. Keeping adulterants out of the food chain requires robust instrumentation that can meet today’s threats while being advanced enough to address tomorrow’s challenges.
Therefore, development of technologies and methods to detect food adulteration is necessary. There are many practical difficulties in developing food authenticity methods, one of the most fundamental being the ability to find a marker that characterizes the food, one of its ingredients, the adulterants or the processing, production or geographic origin. Many advanced analytical approaches to screen for aforementioned food adulteration cases will be discussed below, focusing on methods involving vibrational spectroscopy, nuclear magnetic resonance spectroscopy, mass spectrometry, isotopic analysis, and chromatographic techniques to enable reliable food authentication.
The methodology of analytical methods can be broadly divided into four main types: chemical, physical, DNA, and proteomic based methods. Chemical methods, such as Stable Isotope Ratio analysis, have proved successful in determining the geographic origin of products or the method of production. More typical physical methods, such as microscopy, are being used to identify mechanically separated meat and to screen for wheat and rice adulteration. DNA based methods have proved to be well-suited to spaces identification like meat, fish and fruit. Some of these DNA methods have been transferred to simpler platforms known as “lab on a chip” which has been extended to more than 100 species, including canned fish, rice, orange juice, wheat, and potatoes.
More recently proteomic methods have been used to look at complex and highly processed meat products and identify peptide markets for meats species in highly degraded samples. The first message I will introduce is vibrational spectroscopy. Reliable analytical tools must be available along the food chain to verify the nature of food. Typically several factors drive technique selection including method detection limits simple preparation cost and throughput. Such tools should permit rapid nondestructive and inexpensive analysis. The various techniques available for testing food authenticity include ultraviolet near infrared mid-infrared and Raman spectroscopy methods. All of these are routinely used to control both raw materials and finished food products for specific production standards.
Vibrational spectroscopy is the collected term used to describe two analytical techniques infrared and Raman spectroscopy. These techniques measure molecular vibrations either by the absorption of light quanta or the inelastic scattering of photons. Either method generates spectral signature profiles called fingerprints that are reproducible and distinct for different raw materials as well as adulterants. Vibrational spectroscopic techniques have significant potential in the field of food authentication as they provide resolution of unique chemical information allowing rapid monitoring of subtle compositional changes to help detect potential ingredient tampering. The complex spectrum reflects the total biochemical composition from food constituents. The first test is tea. Tea is the most consumed beverage in the world. The principal importance of tea is due to its health benefits.
Many substances have been used to adulterated tea but the most common kind is color. Therefore, NIR and MIR spectroscopy has been used to determine quality and to classify varieties of tea. The next item is rice. Rice is one of the most produced and consumed cereals worldwide. VIS and NIR spectral data is the powerful tool to determine composition or classify rice according to geographical origin. Hyper spectral imaging was also reported to be effective in rice of authentication studies. The next item is milk products. Milk adulteration by addition of water sugar whey or high solid contents could bring economic problems and health concerns.
MIR and NIR have been used to determine the typical spectral profiles of milk and dairy products, to use as a tool for monitoring the authenticity of these products.
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Introduction to Nutrition and Food Safety

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