A study on AFLATOXIN content in black scented rice in India

Abstract

Black rice is a range of rice types of the species oryza sativa L. It is also known as purple rice, some of which are glutinous rice. Varieties include Indonesian black rice and Thai jasmine black rice. Black rice is known as chak-hao in Manipur which is an Indian state on the eastern border with Myanmar, where desserts made from black rice are served at major feasts. Black rice is a source of iron, vitamin E, and antioxidants (more than in blueberries). The bran hull (outermost layer) of black rice contains one of the highest levels of anthocyanins found in food, which helps in fighting against heart disease, cancer and associated diseases. The grain has similar amount of fiber to brown rice and, like brown rice, has a mild, nutty taste. It  has a deep black color and when cooked, it usually turns purple. Its dark purple color is primarily a product of its anthocyanin content, which is higher by weight than that of other colored grains. It is very useful when making porridge, dessert, traditional Chinese black rice cake, bread, and noodles. Black scented rice also known as Chakhao Amubi is a type of glutinous rice. It is indigenous to northeastern regions of India. It is also called Gold rice as the rice can be exported to countries where there is high demand of sticky rice and fetch foreign exchange. Rice is largely cultivated in subtropical environments which are characteristically warm and humid. After harvesting, it is generally dried and under inappropriate storage conditions, rice is considered as an appropriate substrate for fungal growth. Rice is often contaminated with mycotoxins such as aflatoxins. The temperatures and moisture conditions prevailing during storage promote aflatoxin production resulting in annual losses of useful food bioresources such as rice and thus affecting the economy of rice producing countries. The aflatoxins are a group of chemically similar toxic fungal metabolites (mycotoxins) produced by certain moulds of the genus Aspergillus growing on a number of raw food commodities. Aflatoxins are highly toxic compounds and can cause both acute and chronic toxicity in humans and many other animals. The aflatoxins consist of about 20 similar compounds belonging to a group called the difuranocoumarins, but only four are naturally found in foods. These are aflatoxins B1, B2, G1 and G2. Aflatoxin B1 is the most commonly found in food and also the most toxic and classified by the International Agency for Research on Cancer (IARC) as 1^st class carcinogen. To control the contamination of Aflatoxin in Black Scented Rice, the Rice to be free  from Aflatoxin contamination or contain the permissible limit of same. The objectives of this study was to determine the concentrations of  Aflatoxin B1 in Black scented rice collected from Gauwahti and Shillong i.e North east part of India and also to assess whether the black scented rice  were safe for human consumption. The aflaoxin in Black Scented Rice has been analysed using HPTLC. Out of 87 samples of black scented rice analysed for Aflatoxin, 85 samples were found to be free from Aflatoxin i.e  Below detection limit.  Only two samples showed aflatoxin content of 21.581 ppb and 22.989 ppb respectively. As per FSSAI, the maximum permissible limit for Aflatoxin is 30 ppb. The study showed that the Black scented rice samples collected from North-Eastern regions of India were safe for human consumption.