Table 3.

Effect of aging time in the ketones content, expressed as quantifier area units (AU × 10³/g), of donkey meat steaks aged for 14 days under vacuum conditions (n = 10 samples for each aging time).

			Ageing Time (Days)
Volatile Compound	m/z	LRI	1	3	6	9	14	SEM	p-Value
2,3-Butanedione	43	592	203.73	165.32	145.96	94.94	123.05	39.25	0.586
2-Butanone	72	596	61.77	47.36	69.32	103.30	56.65	2.36	0.096
2-Pentanone	86	720	19.67	16.61	16.78	14.93	16.86	1.90	0.568
3-Pentanone	57	736	77.94	86.39	87.04	46.35	83.31	1445.53	0.447
2,3-Pentanedione	100	739	76.16 a	161.23 b	137.75 a,b	99.43 a,b	149.03 a,b	20.34	0.011
Acetoin	45	787	1735.75	1540.13	1392.70	790.07	436.27	7.06	0.149
2-Hexanone	58	863	52.48 a	38.46 a,b	19.55 b	27.82 a,b	26.74 a,b	0.80	0.016
3-Heptanone	57	960	22.90	32.27	31.33	30.30	34.04	7.75	0.607
2-Heptanone	58	967	1055.89	1285.42	648.08	943.32	1023.91	9.22	0.239
4-Cyclopentene-1,3-dione	96	1003	39.23	71.76	65.49	56.37	50.62	545.25	0.175
4-Hexen-3-one, 5-methyl-	83	1047	54.19	39.88	25.56	29.30	34.18	3.23	0.148
Butyrolactone	42	1049	87.11	61.90	78.59	84.56	79.82	2.10	0.346
2(5H)-Furanone	55	1053	259.73	129.48	80.36	265.89	50.97	91.23	0.282
3-Octen-2-one	55	1111	48.42	70.55	37.78	42.52	73.75	4.79	0.083
3-Octanone, 2-methyl-	43	1141	32.40 a	62.72 a,b	45.55 a,b	34.68 a,b	64.55 b	3.62	0.012
2-Nonanone, 3-(hydroxymethyl)-	43	1146	15.27	17.35	19.34	22.43	17.61	4.39	0.404
Total Ketones			4210.12	2888.86	1347.94	2342.08	913.27	38.21	0.080

Different letters in the same line show statistical differences (^a,b: p < 0.01). SEM: standard error of mean; m/z: Quantifier ion; LRI: Lineal Retention Index calculated for DB-624 capillary column (J&W scientific: 30 m × 0.25 mm id, 1.4 µm film thickness) installed on a gas chromatograph equipped with a mass selective detector. LRI: linear retention index in agreement with literature for the same chromatographic column [25,34,43].