Discrimination of Free-Range and Caged Eggs by Chemometrics Analysis of the Elemental Profiles of Eggshell

Table 3

Analytical results of 16 elements in free-range and caged eggshells.

Elements	Average levels (SD) (μg/g)		DL^a (μg/g)
	Free-range	Caged
Zn	1.72 (0.39)	2.33 (0.51)	0.05
Pb	1.04 (0.27)	2.16 (0.19)	0.09
Cd	0^b	0.34 (0.08)	0.03
Co	0.22 (0.04)	0.32 (0.09)	0.03
Ni	0.44 (0.12)	0.59 (0.10)	0.05
Fe	2.1 (0.6)	3.2 (1.0)	0.04
Mn	0.67 (0.13)	1.01 (0.31)	0.07
Cr	0.71 (0.28)	2.32 (1.03)	0.02
Mg	6042 (2106)	5363 (1849)	0.08
Cu	1.56 (0.31)	2.13 (0.55)	0.07
Se	4.22 (1.68)	2.18 (1.01)	0.04
Ca	366310 (46778)	342560 (35458)	0.08
Al	71.9 (6.5)	88.5 (11.7)	0.10
Sr	120.4 (24.8)	171.3 (44.6)	0.02
Na	2156 (388)	3016 (612)	0.33
K	1850 (302)	2305 (226)	0.76

^aThe detection limit was related to the 3σ signal, where σ was estimated from 11 repeated measurements of the blank. ^bNondetected.