Milk allergen detection

Other applications involve detection of adulteration of dairy products with soy, pea, and wheat proteins (Haasnoot et al., 2001), presence of asrcasein in milk (the detection threshold for this protein was 0.87pg/mL) (Muller-Renaud et al., 2005), [3-casein in milk and cheese (Muller-Renard et al., 2004), and detection of peanut allergenic proteins (the detection threshold for this protein was 0.7 pg/mL) (Mohammed et al., 2001). 

Monaci, L., Tregoat, V., Van Hengel, A.J., and Anklam, E. 2006. Milk allergens, their characteristic and their detection in food. A review. Eur Food Res Technol 223 149-179. 

Naturally, plant ingredients are not the only source of food and drinks. Actually, in advanced developed countries, food from animal source is dominating where milk and meat represent the most concrete examples of drink and food, respectively. Nevertheless, the prevalence of specific applications, such as protein components useful for human health, stimulates the development of plant consumption. As a counterpart, plants also contain threatening protein components (toxins and allergens) that require attention for an improved food security therefore, there is a need of detecting low-abundance proteins (the deep proteome) from plant tissues as schematically illustrated in Figure 1. It is within this context that this chapter purposely limits the discussion to plant proteomics. The description about the situation of low-abundance animal-derived food proteomics has been made by the same authors in various other documents (3-6). 

Exposure to Asteraceous plants may also result in the development of contact dermatitis. One Serbian study has indicated that it is not unusual to detect sensitization to chamomile (Chamomilla recutita), arnica (Arnica montana), tansy (Tanacetum vulgare), and feverfew (Tanacetum parthenium) (Jovanovic et al., 2004). Contact dermatitis, along with asthma and rhinitis, may also accompany occupational exposure to chamomile (Rudzki et al., 2003) and contact dermatitis to feverfew (Hausen, 1981). Similarly, chamomile in cosmetic products can also be a cause of dermatitis (Paulsen, 2002 Rycroft, 2003). Because chamomile-containing products, particularly in shampoos and other OTC products, are so widespread, the linkage to these types of adverse events are likely underreported. Also, use of royal jelly, a thick mixture of honey, pollen, and their allergens, has been associated with several cases of bronchospasm, and topical application of concentrated forms of bee pollen (propalis) to contact dermatitis (Perharic, 1993). Milk thistle has also been known to cause urticaria (De Smet, 2004). 

In clinical diagnosis of sensitivity to allergens in food, the two methods used most frequently are the skin prick test (SPT) and the radioallergosorbent test (RAST). These tests have been used reliably for the diagnosis of allergy to peas, codfish, peanuts, egg white, wheat and wheat flour but were only partly reliable in detecting allergy to cow s milk, sardines, and white bea ns ( ). 

Depending on the food matrix, multiplex DNA can show some discrepancies in the detection of different allergenic targets, due to differential efficiency of the amplification process. This issue has been shown in the case of the determination of the hazelnut allergen isoforms Cor a 1.03 and Cor a 1.04 in some matrices, including dark chocolate, soy milk, lecithin supplement, and snack muesli (Bettazzi et al., 2008). For this reason, multiplex assays must be evaluated carefully during and after development, to reduce inconsistent results. 

Hohensinner V, Maier I, Pittner F (2007). A gold cluster-linked immunosorbent assay optical near-field biosensor chip for the detection of allergenic beta-lactoglobuUn in processed milk matrices. J. Biotechnol, 130(4) 385-388. 

Basically all natural contaminants, such as food allergens or adulterating agents such as cow s milk in other species milk, can be detected by antibody-based applications as well as by alternative DNA-based assays. However, artificially synthesized components can only be determined by the use of immunoassays, since they have no DNA associated with their production. Refer to Chapter 9 for further information on DNA-based assays for food allergens. 

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