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

Table 2

Individual content of volatile compounds before and after vertical centrifugation, storage, and filtration processes, expressed in mg/kg

	Decanter exit	Centrifuge exit/beginning of storage	Unfiltered/end of storage	Filtered
LOX pathway
Hexanal	0.42 ± 0.01^b	0.40 ± 0.01^b	0.56 ± 0.02^a	0.55 ± 0.02^a
Hexan-1-ol	0.38 ± 0.02^b	0.36 ± 0.02^b	0.64 ± 0.06^a	0.61 ± 0.02^a
(E)-2-hexenal	3.25 ± 0.03^a	2.90 ± 0.11^b	3.27 ± 0.22^a	3.13 ± 0.05^a,b
(E)-2-hexen-1-ol	0.24 ± 0.01^b	0.23 ± 0.02^b	0.62 ± 0.01^a	0.65 ± 0.02^a
(Z)-3-hexen-1-ol	1.80 ± 0.04^b	1.61 ± 0.11^b	2.33 ± 0.21^a	2.16 ± 0.06^a
(Z)-3-hexenyl acetate	2.33 ± 0.16^b	2.25 ± 0.10^b	3.07 ± 0.35^a	2.44 ± 0.08^b
1-penten-3-ol	0.28 ± 0.00^a,b	0.23 ± 0.03^b,c	0.21 ± 0.004^c	0.32 ± 0.07^a
1-penten-3-one	0.65 ± 0.02^c	0.56 ± 0.04^b	0.62 ± 0.01^b	0.71 ± 0.02^a
(Z)-2-penten-1-ol	0.45 ± 0.01^a	0.39 ± 0.04^b	0.41 ± 001^a,b	0.46 ± 0.02^a
Sugar fermentation
Ethanol	8.31 ± 0.17^a	3.88 ± 0.09^c	4.70 ± 0.07^c	6.27 ± 0.18^b
Acetic acid	0.64 ± 0.09^b	0.53 ± 0.07^c	0.77 ± 0.04^a	0.55 ± 0.01^b,c
Other compounds
(E)-2-pentenal	0.28 ± 0.01^b,c	0.25 ± 0.03^c	0.29 ± 0.004^b	0.34 ± 0.02^a
Pentan-3-one	0.34 ± 0.01^b	0.31 ± 0.02^c	0.35 ± 0.01^b	0.41 ± 0.01^a
Nonanal	1.96 ± 0.05^c	1.75 ± 0.12^d	2.39 ± 0.05^b	2.63 ± 0.12^a

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.