Centrifugation, Storage, and Filtration of Olive Oil in an Oil Mill: Effect on the Quality and Content of Minority Compounds

Table 1

Quality parameters and sensory characteristics for the oil samples before and after vertical centrifugation, storage, and filtration.

	Decanter exit	Centrifuge exit/beginning of storage	Unfiltered/end of storage	Filtered
Acidity (%)	0.186 ± 0.001^a	0.148 ± 0.001^b	0.122 ± 0.004^c	0.111 ± 0.002^d
Peroxide I. (mEq·O2/kg)	3.07 ± 0.07^d	3.38 ± 0.13^c	4.45 ± 0.03^b	5.00 ± 0.04^a
K232	1.33 ± 0.08^a	1.27 ± 0.19^a	1.46 ± 0.03^a	1.35 ± 0.04^a
K270	0.13 ± 0.01^a	0.12 ± 0.02^a,b	0.106 ± 0.002^b,c	0.096 ± 0.006^c
Chlorophylls (mg/kg)	35.18 ± 1.47^a	32.51 ± 0.90^a	26.41 ± 0.73^b	13.78 ± 0.18^c
Carotenoids (mg/kg)	14.17 ± 0.62^a	13.08 ± 1.06^a,b	12.24 ± 0.32^b	7.73 ± 0.05^c
Total HPLC phenols (mg/kg)	438.37 ± 3.23^a	338.14 ± 3.99^b	224.75 ± 5.47^c	221.40 ± 3.49^c
DPPH (µmol/kg)	1359.83 ± 19.54^a	992.07 ± 8.52^b	221.09 ± 21.56^c	213.71 ± 11.84^c
Total LOX volatiles (mg/kg)	9.82 ± 0.26^b	8.93 ± 0.43^b	11.73 ± 0.88^a	11.02 ± 0.37^a
Fruitiness	6.4 ± 0.6^a	6.0 ± 0.3^a,b	5.8 ± 0.1^b	5.6 ± 0.9^b
Bitterness	3.5 ± 0.3^a,b	3.6 ± 0.3^a	3.2 ± 0.3^b,c	2.9 ± 0.2^c
Pungency	4.1 ± 0.1^a	4.3 ± 0.2^a	3.9 ± 0.1^a,b	3.6 ± 0.4^b

Values are expressed as mean ± SD; (a, b, c, d) indicate Fisher’s least significant differences (LSD), with statistically significant differences at 95% confidence level.