الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 117 |  |  |
| | | from | 117 | | |
Abstract
A total of 100 random samples from raw milk, kareish cheese,romano cheeseand yoghurt (25 of each), were collected from different sources and localities in Beni-Suef city to determine the level of lead, cadmium, copper and zinc in milk and milk products by using UNICAM 969 Atomic Absorption Spectrophotometer.
Also 10 samples of raw milk were collected from different markets in Beni-Suef city. All samples were prepared for manufacture of yoghurt and kareish cheese from each sample to measure the effect of manufacture of milk on concentration of heavy metal residues.
Heavy metal residues in milk and some dairy products:-
Raw milk:-
Lead concentration in raw milk ranged from 0.03 to 5.30 ppm with a mean of 1.318 ±0.267 ppm. Statistical analysis showed that 22 (88%) out of 25 raw milk samples contained lead above the permissible limit.
Cadmium concentration in raw milk ranged from 0.01 to1.94 ppm with a mean of0.463 ± 0.087 ppm. Statistical analysis revealed that 17 (68%) out of 25 raw milk samples contained cadmium above the permissible limit.
Copper concentration in raw milk ranged from 0.04 to 1.13 ppm with a mean of 0.341 ± 0.047 ppm. Statistical analysis showed that 10 (40%) out of 25 raw milk samples contained copper above the permissible limit.
Zinc concentration in raw milk ranged from 2.004 to 11.098 ppm with a mean of 5.464 ± 0.491 ppm. Statistical analysis showed that 16 (64%) out of 25 raw milk samples contained copper above the permissible limit.
The calculated daily intake of Pb, Cd, Cu and Znwere 0.264, 0.093, 0.068 and 1.093 mg per adult person from consumption of 200 ml milk per day and these representing 105.44, 132.3, 0.68 and 15.6 % of provisional ADI, respectively.
Kareish cheese:-
Lead concentration in soft cheese ranged from 0.01 to 2.02 ppm with a mean of 0.767 ± 0.128 ppm. Statistical analysis showed that 19 (76%) out of 25 soft cheese samples contained lead above the permissible limit.
Cadmium concentration in soft cheese ranged from 1.67 to 2.34 ppm with a mean of 1.905 ± 0.032 ppm. Statistical analysis revealed that all (100%) out of 25 soft cheese samples contained cadmium above the permissible limit.
Copper concentration in soft cheese ranged from 0.71 to 1.78 ppm with a mean of 1.127 ± 0.043 ppm. Statistical analysis showed that all (100%) out of 25 soft cheese samples contained copper above the permissible limit.
Zinc concentration in soft cheese ranged from 8.04 to 49.14 ppm with a mean of 14.17 ± 1.676 ppm. Statistical analysis showed that all (100%) out of 25soft cheese samples contained copper above the permissible limit.
The calculated daily intake of Pb, Cd, Cu and Znwere 0.017, 0.042, 0.025 and 0.312 mg per adult person from consumption of 22 gmkareish cheese per day and these representing 6.8, 60, 0.25 and 4.46 % of provisional ADI, respectively.
Romano cheese:-
Lead concentration in hard cheese ranged from 0.12 to 3.96 ppm with a mean of 0.961 ± 0.193 ppm. Statistical analysis showed that 21 (84%) out of 25 hard cheese samples contained lead above the permissible limit.
Cadmium concentration in hard cheese ranged from 1.02 to 1.46ppm with a mean of 1.245 ± 0.025 ppm. Statistical analysis revealed that all (100%) out of 25hard cheese samples contained cadmium above the permissible limit.
Copper concentration in hard cheese ranged from 0.30 to 3.27ppm with a mean of 1.208 ± 0.105 ppm. Statistical analysis showed that 24 (96%) out of 25hard cheese samples contained copper above the permissible limit.
Zinc concentration in hard cheese ranged from 34.49 to 52.82 ppm with a mean of 40.49 ± 0.966 ppm. Statistical analysis showed that all (100%) out of 25 hard cheese samples contained copper above the permissible limit.
The calculated daily intake of Pb, Cd, Cu and Znwere 0.021, 0.027, 0.027 and 0.891 mg per adult person from consumption of 22gmromano cheese per day and these representing 8.45, 38.57, 0.27 and 12.73% of provisional ADI, respectively.
Yoghurt-:-
Lead concentration in yoghurt ranged from 0.08 to 0.61 ppm with a mean of 0.265 ± 0.025 ppm. Statistical analysis showed that 24 (96%) out of 25 yoghurt samples contained lead above the permissible limit.
Cadmium concentration in yoghurt ranged from 0.52 to 6.05 ppm with a mean of 2.479 ± 2.418 ppm. Statistical analysis revealed that all (100%) out of 25yoghurt samples contained cadmium above the permissible limit.
Copper concentration in yoghurt ranged from 0.06 to 1.22 ppm with a mean of 0.326 ± 0.058 ppm. Statistical analysis showed that 8(32%) out of 25yoghurt samples contained copper above the permissible limit.
Zinc concentration in yoghurt ranged from 3.63 to 16.79 ppm with a mean of 5.377 ± 0.529 ppm. Statistical analysis showed that all (100%) out of 25 yoghurt samples contained copper above the permissible limit.
The calculated daily intake of Pb, Cd, Cu and Zn were 0.027, 0.248, 0.033 and 0.538 mg per adult person from consumption of 100 gm yoghurt per day and these representing 10.8, 354.29, 0.33 and 7.69 % of provisional ADI, respectively.
Effect of milk manufacturing on distribution of heavy metals in some dairy products:-
The concentration of lead in raw milk was 1.19 ppm, while in the manufactured yoghurt and kareish cheese were 1.135and 7.47 ppm, respectively.
On the other hand, cadmium concentration in raw milk was 0.05 ppm, but in yoghurt and kareish cheese were 0.06 and 0.05 ppm.
According to copper concentration in raw milk, it was 0.47 ppm but in yoghurt and kareish cheese were 0.37 and 1.79 ppm, respectively.
According to zinc concentration in raw milk, it was 3.32 ppm but in yoghurt and kareish cheese were 1.54 and 8.24 ppm, respectively.
The results declared that the level of Pb, Cu and Zn were highly significant in kareish cheese than in yoghurt.