Table 3.

VOCs profile of raw non-homogenised milk before and after IR treatment using different energies.

Rt	Compound	Raw Milk (n = 3)	S.D. (±)	IR60 (n = 3)	S.D. (±)	IR70 (n = 3)	S.D. (±)	IR80 (n = 3)	S.D. (±)	IR85 (n = 3)	S.D. (±)
Aldehydes
8.98	Hexanal	0.08	0.16	n.d.	-	0.32	0.63	2.90	1.39	4.21 *	1.63
Total		0.08		n.d.		0.32		2.90		4.21 *
Ketones
2.26	2-Propanone	1212.95	268.77	1405.73	328.22	1369.23 *	253.92	1553.42 *	472.97	1613.35 *	583.46
3.12	2-Butanone	282.75	47.46	268.61	103.14	263.53	67.60	284.33	99.82	282.95	86.80
13.01	2-Heptanone, 6-methyl-	0.26	0.29	0.55	0.29	0.89	0.27	2.93 *	2.00	5.01 *	3.61
13.83	2-Heptanone	0.49	0.33	0.80	0.80	0.53	0.37	0.33	0.12	0.37	0.22
14.82	Propanone, 1,1-dichloro-	0.19	0.19	0.21	0.11	0.38	0.21	1.05 *	0.80	1.77 *	1.29
17.67	3-Hydroxy-2-butanone	1.46	1.84	2.08 *	2.81	2.02 *	2.43	1.06	0.84	0.74	0.24
Total		1498.11		1677.98 *		1636.58 *		1843.13 *		1904.19 *
Sulphur compounds
1.90	Dimethyl sulphide	48.37	15.09	58.57 *	25.59	57.37 *	20.13	57.78 *	19.86	58.76 *	20.86
8.32	Dimethyl disulphide	n.d.	-	0.23	0.27	0.05	0.09	0.33	0.46	0.12	0.11
31.05	Dimethyl sulphone	10.76	6.48	10.08	5.06	14.79	2.94	13.00	4.15	26.40 *	11.63
Total		59.13		68.88 *		72.21 *		71.11 *		85.28 *

Data expressed as ng g⁻¹ SI equivalents; * indicates a significant statistical difference compared to raw milk (p < 0.05); n.d., not detected.