3.2. Colour
The analysis of the response surface showed that storage period
(Sp, days) had a significant effect (P < 0.05) on colour changes of
tomato fruits, mainly on a⁄ colour parameter.
The response surfaces representing ultrasounds effect on whole
tomato colour (a⁄
) are shown in Fig. 1 and described by Eq. (2)
(Table 4). The range of power levels lower than 40% and higher
than 70% conducted to green colour stability and fruits ripening
delay. The lower a⁄ values observed in all US treated samples during
the first 8 days of storage at 10 C, demonstrate that tomato
fruits treated with ultrasounds present better storage stability.
The US-treated samples with a period of time lower than 6 min