Table 1.

Must characteristics in three Spanish autochthonous grapevine varieties cultivated at (1) ambient (~400 µmol mol⁻¹) CO₂ concentration (AC) and ambient temperature (AT) (ACAT); (2) AC and elevated (T + 4 °C, ET) temperature (ACET); (3) elevated CO₂ (700 µmol mol⁻¹, EC) and AT (ECAT), and (4) EC and ET (ECET). Values are means (n = 3–6). Within each parameter and grapevine variety, values followed by same letter or with absence of letters do not differ significantly (p ≥ 0.05). Significance of analysis of variance (ANOVA): *** p ≤ 0.001; ** p ≤ 0.01; * p ≤ 0.05; ns, not significant (p ≥ 0.05). T = temperature factor.

	Treatments				ANOVA
	ACAT	ACET	ECAT	ECET	CO2	T	CO2 × T
Tinto Velasco (TV)
Total soluble solids (°Brix)	20.3 a	18.1 ab	17.0 b	16.9 b	*	ns	ns
Must pH	3.95 b	4.03 ab	3.84 b	4.26 a	ns	**	ns
Titratable acidity (g L−1)	4.85 b	3.55 ab	3.05 a	2.69 c	ns	*	***
Soluble solids/Titratable acidity	4.30 b	5.20 ab	5.66 a	6.28 a	ns	*	***
Color density	2.63 a	2.57 a	2.53 ab	1.95 b	ns	ns	ns
Tonality index	0.77 c	0.92 b	0.75 c	1.28 a	***	***	***
Ambrosina (AMB)
Total soluble solids (°Brix)	20.9	20.4	20.3	21.4	ns	ns	ns
Must pH	3.93	3.76	3.82	4.03	ns	ns	ns
Titratable acidity (g L−1)	4.64	4.88	5.38	4.15	ns	ns	ns
Soluble solids/Titratable acidity	4.73	4.37	4.06	5.28	ns	ns	ns
Color density	2.22 ab	1.59 b	2.44 a	2.40 a	ns	ns	ns
Tonality index	0.78 b	1.14 a	0.74 b	0.84 b	*	**	*
Pasera (PAS)
Total soluble solids (°Brix)	21.0 a	21.7 a	22.9 a	22.2 a	ns	ns	ns
Must pH	3.91 b	4.24 a	4.00 ab	4.21 a	ns	**	ns
Titratable acidity (g L−1)	3.94 a	4.18 a	4.88 a	4.68 a	ns	ns	ns
Soluble solids/Titratable acidity	5.46 a	5.36 a	4.76 a	5.09 a	ns	ns	ns
Color density	2.46 a	2.24 a	2.18 a	2.34 a	ns	ns	ns
Tonality index	0.77 b	0.90 a	0.80 ab	0.90 a	ns	**	ns