Table 3. The physicochemical characteristics of single and double distilled brandy aged with oak chips for four weeks

Sample	Adjust to 25% alcohol
Sample	pH	Total acid (acetic acid, %)	Soluble solid (°Brix)	Volatile acid (acetic acid, mg/L)	Formic acid (mg/100 mL)	Acetic acid (mg/100 mL)	L^*4)	a^*	b^*	ΔE^*
20B1L¹⁾²⁾	3.59±0.01^c3)	0.04±0.00^ab	10.47±0.05^ab	404.00±5.74^c	1.89±0.68^bc	6.64±0.22^c	67.61±0.00^b	14.89±0.01ⁱ	70.32±0.02^j	77.11±0.02ⁱ
20B1M	3.57±0.03^c	0.04±0.00^bc	10.53±0.09^a	475.40±1.57^b	1.04±0.37^cd	8.36±0.51^b	62.05±0.00^h	20.68±0.00^e	72.46±0.06^e	82.53±0.05^d
20B1D	3.58±0.03^c	0.04±0.00^c	10.47±0.05^ab	401.80±5.57^c	1.55±0.02^bcd	8.99±0.11^b	61.37±0.01^j	21.68±0.02^b	73.70±0.03^c	84.15±0.02^c
20B2L	3.72±0.05^a	0.03±0.00^d	10.10±0.08^e	334.13±4.06^g	0.91±0.28^d	3.77±0.08^f	68.09±0.01^a	14.76±0.00^j	68.73±0.04^k	75.46±0.03^j
20B2M	3.65±0.02^b	0.03±0.00^d	10.17±0.05^de	386.47±1.27^d	1.99±0.70^bc	4.17±0.05^ef	64.42±0.00^e	19.51±0.00^f	71.21±0.02ⁱ	80.17±0.02^h
20B2D	3.71±0.01^ab	0.03±0.00^de	10.17±0.05^de	336.53±1.73^g	1.94±0.27^bc	4.53±0.10^ef	62.64±0.02^g	21.77±0.01^a	72.35±0.01^f	82.47±0.02^e
30B1L	3.49±0.02^d	0.04±0.00^c	10.37±0.05^bc	478.20±1.99^b	3.31±0.22^a	8.52±0.08^b	66.07±0.00^d	16.64±0.01^h	73.06±0.03^d	80.52±0.03^g
30B1M	3.43±0.01^e	0.04±0.00^a	10.37±0.05^bc	537.13±6.03^a	1.67±0.42^bcd	10.94±0.96^a	60.58±0.01^k	21.36±0.00^d	74.67±0.03^b	85.24±0.02^a
30B1D	3.50±0.03^d	0.04±0.00^ab	10.30±0.08^cd	477.73±2.38^b	2.14±0.33^b	11.59±1.13^a	61.37±0.00^j	21.43±0.00^c	74.88±0.02^a	85.11±0.02^b
30B2L	3.75±0.01^a	0.03±0.00^e	10.23±0.05^cd	357.13±1.48^e	0.81±0.20^d	4.09±0.24^ef	67.42±0.01^c	14.49±0.00^k	66.61±0.04^l	73.76±0.03^k
30B2M	3.69±0.04^ab	0.03±0.00^de	10.27±0.05^cd	392.27±3.80^d	1.93±0.59^bc	4.92±0.08^de	64.11±0.01^f	18.90±0.01^g	71.60±0.00^g	80.49±0.00^g
30B2D	3.73±0.03^a	0.03±0.00^de	10.27±0.05^cd	349.27±3.80^f	1.37±0.28^bcd	5.56±0.30^d	61.94±0.01ⁱ	21.78±0.03^a	71.34±0.04^h	81.88±0.04^f

20B1, single distillation of 20 °Brix wine; 20B2, double distillation of 20 °Brix wine; 30B1, single distillation of 30 °Brix wine; 30B2, double distillation of 30 °Brix wine.
L, light oak chip; M, medium oak chip; D, dark oak chip.
Values are mean±SD (n=3). Different superscript letters within a column indicate significant differences at p<0.05.
The L^* value represents lightness, while a^* and b^* correspond to the red-green and yellow-blue color axes, respectively, in the CIE Lab^* color space.