Enzyme immunoassay for the quantitative determination of Mustard in food.
Background: Mustard belongs to the Brassica plants. With about 30-35% the fraction of proteins in mustard seed is very high. Some of these proteins are known for being allergenic, such as Sin a 1 and Bra j 1. These proteins are predominantly heat resistant making them stable to different production processes. In addition to brown mustard (Brassica juncea) and black mustard (Brassica nigra) primarily yellow mustard (Sinapsis alba) is used as an ingredient in many foods and food preparations. For mustard allergic persons hidden mustard allergens in food are a critical problem. Already very low amounts of mustard can cause allergic reactions, which may lead to anaphylactic shock in severe cases. Because of this, mustard allergic persons must strictly avoid the consumption of mustard or mustard containing food. Cross-contamination, mostly in consequence of the production process, is often noticed. The sausage production process is a representative ex-ample. This explains why in many cases the existence of mustard residues in food cannot be excluded. For this reason sensitive detection systems for mustard residues in foodstuffs are required.
The Mustard ELISA represents a highly sensitive detection system for yellow mustard and is particularly capable of the quantification of residues in sausage, dressings, soups, cheese and mixed herbs. Due to high cross-reactivity the test is also suitable for the detection of brown mustard and black mustard.
Description: The Mustard quantitative test is based on the principle of the enzyme linked immunosorbent assay. An antibody directed against mustard proteins is bound on the surface of a microtiter plate. Mustard containing samples or standards are given into the wells of the microtiter plate. After 20 minutes incubation at room temperature, the wells are washed with diluted washing solution to remove unbound material. A peroxidase conjugated second antibody directed against mustard proteins is given into the wells and after 20 minutes of incubation the plate is washed again. A substrate solution is added and incubated for 20 minutes, resulting in the development of a blue colour. The colour development is inhibited by the addition of a stop solution, and the colour turns yellow. The yellow colour is measured photometrically at 450 nm. The concentration of mustard is directly proportional to the colour intensity of the test sample.
- The kit contains reagents for 96 determinations;
- Microtiter plate consisting of 12 strips with 8 breakable wells;
- Mustard Standards: 0, 2, 6, 20, 60 ppm;
- ELISA reader at 450 nm;
- Standard range: 2 - 60 ppm;
- Sensitivity analytical: 1 ppm.