Source of variation1 Ascorbic acid Total phenolic compounds Antioxidant activity
Regression model 8,80 b 1,87ns 1,08ns 7,20b
P 21,50c 18,38 c 33,12c 16,19d
T 83,25c 54,18 c 147,19b 72,98b
t 529,04b 14,17 c 116,60b 272,24c
P2 33,80c ns 763,88b 0,25ns
T2 12,10b 18,08 c 359,49b 15,30d
t2 21,24c 23,43ns 235,81b 15,79b
PT 5,84ns ns 49,86c 0,03ns
Pt 9,12d 17,30 c 36,39c 15,87d
Tt ns ns ns 6,58ns
Lack of fit 12,23ns 15,95ns 268,74ns 8,57ns
R2 0,9164 0,51223 0,4462 0,9052
1P=pressure. T=temperature. t=time.
ap ≤ 0.01. bp ≤ 0.05. cp ≤ 0.10
Table 3: ANOVA (F value) of the quadratic model for ascorbic acid content. total phenolic compounds and antioxidant activity of the HHP treated orange juice.