The Authenticity of Basmati Rice – A Case Study
Basmati rice is a high-value, aromatic rice with unique eating properties grown in Northern India and Pakistan. Because of its high value, it is susceptible to adulteration with non-Basmati rice. When research commenced, 15 varieties of rice were approved as Basmati by the Indian and Pakistani authorities. DNA microsatellites were chosen as DNA markers for Basmati authenticity, and a 10-microsatellite protocol developed to identify both Basmati and non-Basmati varieties. Also, a quantitative test was developed using one of the microsatellites. This protocol was used for a UK-wide survey of the Basmati market, which showed serious levels of adulteration with non-Basmati. The DNA method was further developed, and an eight-microsatellite protocol was tested in an international ring trial. As part of the Government's programme to transfer DNA methodology to UK official control laboratories, new insertion and deletion (InDel) markers were chosen to adapt the test to a lab-on-a-chip platform. A two-stage protocol using six InDel markers was developed as a screening test, which identified groups of Basmati and non-Basmati varieties. More recently, plant breeders have produced more varieties approved as Basmati. This presents a new challenge to either upgrade the existing methodology or to find new DNA markers to authenticate all the new varieties of Basmati and the commercially available non-Basmati varieties.