Variations in the transfer of radiocesium (~(137)Cs) and radiostrontium (~(90)Sr) from milk to cheese

摘要

This study aimed to compare the transfer of 2 man-made radionuclides, radiocesium (~(137)Cs) and radiostrontium (~(90)Sr), from cow milk to whey and cheese in 3 different types of French cheese production with rennet coagulation. Most of the ~(137)Cs was present in the aqueous phase and became concentrated in the whey. For ~(137)Cs transfer to whey, the processing factor (Pf; i.e., the ratio of the activity concentrations) ranged between 0.86 and 1.30 (n = 12). The food processing retention factor (Fr), calculated using the processing efficiency, ranged between 0.85 and 1.19 (n = 9). No statistical difference of Pf and Fr to whey is identified for ~(137)Cs and the cheese products. The Pf calculated for ~(90)Sr transfer to cheese ranged between 3.95 and 12.16, with significant differences depending on the type of cheese. In addition, a linear correlation is observed between ~(90)Sr Pf to cheese and the Ca level in the cheese (r~2 = 0.57). Thus, the Pf is enhanced in hard cheeses that are enriched in calcium. This is confirmed by nearly constant Fr values, ranging between 0.66 and 0.83.