53 / 2021-10-14 18:13:21

Evaluation of Water-Injected Meat with T2 distribution of SE sequence and DWI sequence by MRI

MRI,water-injected meat,Food safety,SE sequence,SE-FID sequence,DWI sequence,T2 mapping,ADC

Aim and Objectives: Red meat is a common food in people's daily life and its quality affects people’s health directly.  Water-injected meat is the raw meat which is injected with certain amount of water before or after slaughtering to increase the weight. The higher the content of water is, the faster the growth of microorganisms. Therefore, it is crucial to find a fast and nondestructive method to evaluate the water-inject meat. This study aims to use MRI to evaluate whether the meat is injected with water and the water injection rate.



Materials and Methods: The meat used in this project is lean pork without lipid tissue and the MRI machine is the clinical 1.5T MRI scanner (XGY Magicscan-1.5, Ningbo, China). Two MRI methods are used in this project. One is based on T2 distribution of the sample scanned by SE (spin-echo) sequence and SE-FID sequence (SE sequence without Phase and frequency encoding) with different TE from 20ms to 80ms. The other method uses ADC (apparent diffusion coefficient) as the index to show the difference between the meat with and without water injection measured by DWI sequence.



Results and Discussion: Figure 1 displays the comparison of T2 mapping between meat without(a) and with injection of water by SE sequence. It shows that T2 can be used to evaluate the water-injected meat. Table 1 is the T2 distribution (T2>70ms) of red meat by SE sequence, and the evaluation criterion is 3.3%. Table 2 is the T2 distribution(58ms58ms for SE-FID sequence (y= 9.233x-9.751 for 1.056

Conclusion: For the water-injected meat detection based on T2 distribution, the SE-FID sequence is more suitable than the SE sequence. The relationship between T2 relaxation time distribution and water injection rate is linear which could be used to determine whether the meat is injected by water and the specific water injection rate. However, this method relatively slow (within 2 mins for each sample) and is insensitive to the low injection rate. While the DWI method could distinguish the water-injected meat even the water injection rate is low with faster speed (about 20 seconds). 



Figures

     

FIG. 1. T2 mapping of meat (a) without injection, (b) with 10% injection by SE sequence.

 

Sample	T2>70ms			Practical injection rate
	Without injection		10% injection
1	0.76%		8.62%	9.35%
2	1.70%		18.39%	8.95%
3	1.66%		5.2%	3.66%
4	1.44%		6.3%	0.95%
Evaluation Criterion		3.3 %

Table. 1. T2 distribution of red meat by SE sequence

 

Sample	58ms			Practical injection rate
	Without injection		10% injection
1	8.41%		43.09%	5.77%
2	16.31%		60.02%	7.82%
3	10.85%		68.87%	8.02%
4	9.65%		31.67%	6.5%
Evaluation Criterion		24.0 %

 Table. 2. T2 distribution of red meat by SE-FID sequence





Figure 2. The correlation between real injection rate and proportion of T2>58ms for SE-FID sequence

 

Designed injection rate	Sample	First slice	Second slice	Third slice	Average ADC	Real injection rate
0%	1	1.030	1.095	1.030	1.051	0%
	2	1.069	1.157	1.372	1.199	0%
	3	1.264	1.372	1.642	1.426	0%
	4	1.497	1.488	1.499	1.495	0%
10%	1	1.563	1.587	1.639	1.596	3.11%
	2	1.768	2.030	2.222	2.007	3.74%
	3	1.610	1.709	1.659	1.659	3.12%
	4	1.686	1.793	1.836	1.771	3.10%

Table. 3. The ADC value of sample by DWI sequence.



References:

[1]      J. Xu, Q. Lin, F. Yang, Z. Zheng, and Z. Ai, "Study of the method of water-injected meat identifying based on low-field nuclear magnetic resonance," vol. 108, ed, 2018, p. 42053.

[2]      Y. Leng, Y. Sun, X. Wang, J. Hou, X. Bai, and M. Wang, "A method to detect water-injected pork based on bioelectrical impedance technique," Journal of Food Measurement and Characterization, vol. 13, no. 2, pp. 1341-1348, 2019, doi: 10.1007/s11694-019-00049-z.

[3]      Ni Zecheng. “The reasons and countermeasures for water-injected meat,” Journal of Agricultural Sciences 2016,37 (4): 89-92.

[4]      S. Gai et al., “Application of low field nuclear magnetic resonance technology in the quality and safety analysis and detection of meat,” Journal of Food Safety and Quality, vol. 9, no. 20, pp. 5294-5300, 2018.10. (in Chinese)

*Corresponding Author: Chengbo Wang, Tel: 0574-88180000-9894, E-mail: Chengbo.Wang@Nottingham.edu.cn;