Fig. 1. Sample
1—10 are the laser operating points

Fig. 2. LIBS experimental setup

Fig. 3. LIBS spectra of pork muscle and fat
(a): Muscle; (b): Fat

Fig. 4. LIBS spectra of different parts of pork
(a): Hind leg; (b): Streaky pork; (c): Tenderloin;(d): Plum blossom; (e): Front leg

Fig. 5. Distribution of element intensity ratio for different parts of pork
(a): I_{Al 422 nm}/I_{Ca 393 nm}; (b): I_{Mg 280 nm}/I_{Ca 393 nm};(c): I_{K 770 nm}/I_{Ca 393 nm}; (d): I_{Na 589 nm}/I_{Ca 393 nm}

Fig. 6. Spectral principal component scores of 5 types of pork