Gluten
Background:
Gluten is the main group of proteins in grains and consists of prolamins (in wheat: gliadin) and glutelins (in wheat: glutenins) occurring in the same ratio. Due to its physicochemical characteristics, gluten is used in food products as a binder. Coeliac disease is an autoimmune disorder of the small intestine. It is caused by a reaction to gliadin and the only effective treatment is a lifelong gluten-free diet. Due to Codex Standard 118-1979, “gluten-free” products must comply with gluten levels (including prolamin fractions from wheat, rye, barley and oats) below 20 mg/kg (ppm) and “foods specially processed to reduce gluten content” must comply with levels between 20 and 100 mg/kg (ppm).
This analysis is intended to confirm the absence of Gluten in food, rinse waters and swab samples.
Method
AOAC 061403 Romer Labs AgraStrip Gluten G12
Apparatus
Romer Labs AgraStrip
Turn Around Time
Same Day for Swabs
5 to 10 Business Days for Product
Sample Required – Swab
5cm x 5cm (25 cm2) or 10cm x 10 cm (100 cm2)
Sample Required – Product
0.2 grams of a representative sample
Sample Required – Rinse Water
0.5 mL Rinse Water
Type of Test
Lateral Flow Device; Test Strip
Reportable Units
Product: ppm = mg/L
Swabs: µg/cm2
detection limit – swab
Lower Detection Limit: 4 µg/25 cm2 or 1 µg/100cm2 Gluten
detection limit – Product
Lower Detection Limit: 5ppm, 10ppm, or 20ppm Gluten
detection limit – Rinse water
Lower Detection Limit: 0.35 ppm (35 ppb) Gluten
Analysis Description:
Immunological rapid test in lateral flow format for the detection of Gluten in food, rinse waters and swab samples (environmental samples). The test kit uses a new monoclonal antibody called G12 that specifically recognizes the pathogenic fragment of the gliadin protein present in gluten. This fragment is called 33-mer and triggers the auto-immune reaction in coeliac patients. The extracted sample is transferred to an incubation vial that contains specific ready-to-use antibodies. During the test, if the sampel contains Gluten, the sample reacts with a coloured conjugate (anti-gliadin 33mer monoclonal antibody-red-coloured microsphere) which forms a complex with the reagent on the strip. This complex spreads along the membrane by capillary action and is therefore detected by the test strip.
Notes:
This assay is not appropriate for food products which are known to contain Gluten. If the sample contains more than 1% (10,000 ppm) Soy, the assay will be overwhelmed and give a false-negative result.
Sampling:
Consideration must be taken that the food may contain an uneven distribution of Gluten (spot contamination). It is important to provide a representative portion of food as only a small amount of material is tested.
