Abstract:
Dairy products are an important source of many nutrients and micronutrients in the diets of children and adults both. Considerably large amount of milk-based sweetmeats, produced in Rajshahi metropolitan city (area about 100 km²) in Bangladesh, are being consumed regularly by the city dwellers. An attempt was made to investigate the physical quality, as well as the level of Ca and several trace elements e.g. Zn, Cu, Pb, Cd, Cr, Co, Mn, and As, for some common and popular indigenous local sweetmeats. Most of the analyses are done by Atomic absorption spectrophotometer, in which detection limits were obtained from fractional ppb (0.51 ppb for Arsenic) to as high as 71 ppb (for Lead). To justify the quality of products, the levels of the measured elements and other physical parameters were compared with the data from fresh milks and referred values for similar materials. Usually, levels of each mineral are expressed in terms of fresh weight of two selected milk-based sweet items considered here as a standard serving in a meal.
The levels of Ca and Cu were found more or less justifiable in relation with its level in liquid milk equivalent. However, amounts of Zn and Co, two important micronutrients, were found significantly lower in all sweetmeats compared to the certified reference values. On the contrary, Cr, Pb, Cd and As contents were found considerably higher, and interestingly the levels of As and Pb were well above of any other standard permissible limits.
A tentative conclusion was made that milk-based consumables are possibly adulterated with some inferior ingredients which would be the sources of those higher levels of toxic metals, and its consequences in public health are addressed in relation with scanty amount of per capita health expenditure of the country. Eventually, it is also assumed that chemists could put an important role in this direction by analyzing regularly more and more liquid milk and milk-based food items in their routine analysis by setting a well-equipped analytical laboratory, so that they can assure the standards of any consumables for the people of the country.
Description:
This thesis is Submitted to the Department of Chemistry, University of Rajshahi, Rajshahi, Bangladesh for The Degree of Doctor of Philosophy (PhD)