Résumé :
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Magnetic resonance imaging (MRI) has been used to survey the structure of a range of chocolate products, including tablet, straightline and countline products: typically two dimensional MRI at 2 Tesla gives 50 X 50 mm spatial resolution for a 3 mm thick slice in 8 mins. High signal intensity and excellent image contrast is obtained for nuts or other fat fillings; however, dried fruits and biscuit both show a low signal intensity Quantitative MRI of the bars provides diverse measurement of the MRI parameters M-0, T-1, T-2. Although the image contrast from T-1 variations is small that from T-2 is substantial. Thus, whereas chocolate has T-2 values in the range 9 to 17 ms, the T-2 values for nuts and fat fillings are high (> 40 ms), and consequently the)? show with high intensity in spin echo sequences with echo time (TE) = 6 ms.
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