Species specific detection of adulteration of water buffalo milk with cow milk using high resolution melting analysis
Date
2015
Authors
Musetti, James, author
Stone, Martha, advisor
Bunning, Marisa, advisor
Hyatt, Doreene, committee member
Journal Title
Journal ISSN
Volume Title
Abstract
Economically motivated adulteration, a subset category of food fraud, was defined in 2009 by the Food & Drug Administration (FDA) as "the fraudulent, intentional substitution or addition of a substance in a product for the purpose of increasing the apparent value of the product or reducing the cost of its production," and can often encompass effects of public safety through the unknown addition of allergens, toxins, and hygienic risks (Wheatley & Spink, 2013). According to the FDA database which tracks scholarly records of adulterated foods, dairy products are the second most reported adulterated food products (Moore, Spink, & Lipp, 2012). Water buffalo milk represents the second most produced milk worldwide and higher value dairy raw products make it subject to economically motivated adulteration by means of dilution with cow milk (Bonfatti, Giantin, Rostellato, Dacasto, & Carnier, 2013). It is of interest to consumers, manufacturers and governing bodies to have a simple, fast, accurate, and sensitive method to detect adulteration in water buffalo milk. Several methods have been developed to detect species adulteration in dairy products including immunological, chromatography, and molecular methods (Mayer, 2005). In this investigation a real-time PCR assay was developed to specifically detect and relatively quantify cow milk adulteration in water buffalo milk utilizing high resolution melting analysis. A duplex real-time PCR reaction was performed targeting mitochondrial DNA in both species of interest and the resulting amplified products were analyzed after a melt cycle was performed. Results indicated that the assay was specific, efficient, and validated the use of real-time PCR for analysis. The use of high resolution melting analysis allowed for the discrimination of dilution of water buffalo milk with cow milk down to 0.1%. This study indicates the feasibility of real-time PCR and high resolution melting analysis in the detection of adulteration in dairy products.