Table 3.

Mean values and standard deviation of the volatile organic compound content for the four specimens of olive oil samples during storage.

Storage Time (Months)	FIL-HHP			FIL			HHP			CON			p F	p HP	p T	p F × T	p F × HP	p HP × T
	0.5	1	6	0.5	1	6	0.5	1	6	0.5	1	6
Sum of C5 compounds	1.7 ± 0.3	1.6 ± 0.3	1.6 ± 0.4	1.8 ± 0.3	1.5 ± 0.4	1.6 ± 0.4	1.5 ± 0.3	1.2 ± 0.1	1.2 ± 0.1	1.4 ± 0.0	1.5 ± 0.1	2.4 ± 1.4	ns	ns	ns	ns	Ns	ns
Sum of C6 compounds	33.7 ± 7.1	33.8 ± 3.7	25.9 ± 2.5	35.0 ± 9.2	32.5 ± 3.1	22.9 ± 0.9	30.2 ± 5.8	29.8 ± 2.5	22.8 ± 2.5	34.1 ± 4.2	29.4 ± 7.5	21.7 ± 4.2	ns	ns	*	ns	Ns	ns
E-2-hexenal	30.2 ± 5.2 ax	30.6 ± 5.7 ax	22.6 ± 6.7 bx	31.4 ± 8.7 ax	29.3 ± 11.6ax	19.7 ± 2.3 bx	26.9 ± 3.1 ay	27.1 ± 3.1 ay	20.3 ± 8.8 by	27.5 ± 2.3 ay	19.8 ± 2.0 ay	13.1 ± 0.4 by	**	ns	***	ns	Ns	ns
Sum of microbial metabolite compounds	9.8 ± 2.6	8.3 ± 0.9	8.7 ± 0.6	9.7 ± 2.4	7.4 ± 1.1	9.2 ± 0.9	8.8 ± 2.0	6.6 ± 0.5	8.2 ± 0.5	7.6 ± 0.9	19.2 ± 9.5	35.2 ± 10.2	ns	ns	ns	ns	*	ns
Sum of C7, C8, C9 and C10 compounds	1.7 ± 0.1	1.7 ± 0.2	2.2 ± 0.3	1.4 ± 0.1	1.6 ± 0.2	2.2 ± 0.2	1.2 ± 0.1	1.7 ± 0.1	1.9 ± 0.1	4.2 ± 2.1	1.9 ± 0.1	1.8 ± 0.1	**	**	ns	ns	**	ns

*, ** and *** indicate significant differences by 3-way ANOVA at p < 0.05, p < 0.01 and p < 0.001, respectively, for the treatments (F = filtration; HP = high pressure), the storage time (T) and their interaction; different letters (i.e., a, b, c for the three storage times; x, y for filtered and unfiltered samples) indicate a statistically significant difference of the main effects with the Tukey HSD post hoc test (p < 0.05), while the significant interactions are discussed in the main text. ns = not significant. CON = veiled and not HHP-treated oil samples; HHP = veiled and HHP-treated oil samples; FIL = filtered and not HHP-treated oil samples; F-HHP = filtered and HHP-treated oil samples. All concentrations are expressed in mg/kg. Number of replicates = 4.