3.4. Total phenolic content
The response surfaces representing ultrasounds effect on total
phenolic content (TPC) of whole tomato are shown in Fig. 3 and
described by Eq. (4) (Table 4). Ultrasounds treatment power level
(PL) and time (t), as well as storage period (Sp) have a significant
effect (P < 0.05) on whole fresh tomato TPC.
From the data plot analysis, it can be stated that ultrasounds
performed at the range of 40–100% and for more than 4 min
promote higher content of phenolic compounds (>28 mg GAE
100 g1
) (Fig. 3A). Treatments with higher power level and shorted
period of time revealed a drastic reduction of phenolic compounds
(14%). Lower power level for long periods of time treatments