Table 6
Effect of HPP on color in birch sap during storage at 5 and 10℃

Sample1)	Storage period (day)	Hunter's parameter
		L (lightness)	a (redness)	b (yellowness)	ΔE
		C-5	1	99.70±0.022)^c3)	-0.15±0.04^a	0.79±0.02^a	-
7	99.63±0.02^b		-0.03±0.02^b	0.83±0.05^a	0.14
13	99.49±0.02^a		0.13±0.02^c	1.56±0.01^b	0.85
H-5	1	99.34±0.01^bcd	-0.03±0.02^ab	1.13±0.02^a	-
	7	99.32±0.03^abc	-0.03±0.02^ab	1.14±0.02^a	0.03
	13	99.29±0.06^abc	-0.04±0.01^a	1.15±0.03^ab	0.06
	18	99.28±0.03^abc	0.00±0.01^b	1.20±0.02^bc	0.1
	24	99.26±0.05^abc	-0.03±0.02^ab	1.15±0.02^ab	0.09
	30	99.22±0.11^a	-0.03±0.01^ab	1.20±0.03^bc	0.14
	36	99.37±0.04^cd	-0.01±0.02^ab	1.23±0.06^cd	0.11
	42	99.43±0.08^d	-0.01±0.02^ab	1.22±0.03^c	0.13
	45	99.25±0.07^ab	-0.01±0.03^ab	1.28±0.04^d	0.18
C-10	1	99.75±0.03^2)c3)	-0.13±0.03^a	0.61±0.03^a	-
	4	99.69±0.01^c	-0.06±0.01^b	0.83±0.02^b	0.24
	8	99.26±0.04^b	0.14±0.03^c	1.67±0.01^c	1.2
	13	98.70±0.18^a	0.30±0.02^d	2.22±0.01^d	1.97
H-10	1	99.26±0.05^ab	-0.03±0.02^ab	1.18±0.06^a	-
	4	99.19±0.05^a	-0.04±0.01^ab	1.19±0.01^a	0.07
	8	99.20±0.05^a	-0.05±0.02^a	1.15±0.02^a	0.07
	13	99.33±0.08^bc	-0.03±0.02^ab	1.08±0.03^a	0.12
	16	99.37±0.06^c	-0.02±0.03^abc	1.12±0.10^a	0.13
	21	99.32±0.06^bc	0.01±0.02^bc	1.07±0.04^a	0.13
	24	99.36±0.05^bc	0.03±0.04^c	1.04±0.03^a	0.18
	28	99.27±0.03^abc	-0.02±0.06^d	1.36±0.16^b	0.26

C-5, non-treated birch sap during storage at 5℃; H-5, birch sap treated with 550 MPa pressure for 120 sec during storage at 5℃; C-10, non-treated birch sap during storage at 10℃; H-10, birch sap treated with 550 MPa pressure for 120 sec during storage at 10℃.
Values are means±SD of triplicate determinations.
Different superscripts within the each column (storage temperature groups) indicate significant differences (p<0.05).