## 3 Results and Discussion
### Evaluation of Colourimetric Properties  
The freshly prepared smoothie sample had a pinkish colour. Overall, the samples exhibited minimal change in colour due to treatment and storage (Table 3). As a result of the treatments, on day 0, there was a slight increase in L*, while a* slightly decreased and b* slightly increased. However, samples stored for 14 days showed a slight decrease in lightness factor and a slight increase in a* value when control samples were compared to the treated ones. [PERSON] et al. (2016) also observed a similar trend in L* for strawberries during 4-6 weeks of storage. The treated samples demonstrated a reduction in their a* values in comparison to the control. The treated samples exhibited a decrease of 10.18% and 14.80% in a* values, respectively, compared to the control. The loss of red colour in the samples is attributed to residual enzyme activity, which causes enzymatic browning of phenolic compounds. [PERSON] et al. [56] found a similar trend for the a* parameter in a fruit smoothie treated at 350 and 450 MPa. The order of the treatments did not have a significant effect on the colour of the samples. The same conclusion was drawn in our previous study of strawberry puree samples that applied higher treatment levels of HHP and mild heat treatment [57]. A comparison between the fresh samples and those stored for 14 days revealed significant differences in almost all cases, with the exception of the light factor L*. The only exceptions were the b* and C* values of the fresh control and stored controls and the chromium values of the fresh and stored 250 MPa-60 \({}^{\circ}\)C treated samples. A comparison of the fresh samples revealed no significant differences in L* and chromium values. However, for the remaining parameters, the control sample differed significantly from the treated sample. When comparing the samples stored for 14 days, no significant differences were observed between the samples with respect to the L* and b* factors. However, in all other cases, the control sample demonstrated significant differences from the treated samples. Additionally, the two samples treated in different orders also showed differences, particularly with regard to the a* and hue angle. A comparison of the colour of the samples can be made on the basis of the measured colour factors and the colour difference (\(\Delta\)E*). Table 4 presents the calculated \(\Delta\)E* values, which were calculated in relation to both the control sample and each other. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & **Control,** & **60 \({}^{\circ}\)C-250 MPa,** & **250 MPa-60 \({}^{\circ}\)C,** & **Control,** & **60 \({}^{\circ}\)C-250 MPa,** & **250 MPa-60 \({}^{\circ}\)C,** \\  & **Fresh** & **Fresh** & **Fresh** & **14 th Day** & **14 th Day** & **14 th Day** \\ \hline Control, & & 2.18 & 2.42 & 1.57 & 1.04 & 0.93 \\ fresh & noticeable & noticeable & noticeable & noticeable & barely noticeable & noticeably \\
60 \({}^{\circ}\)C-250 MPa, & & & 0.35 & 1.08 & 2.20 & 1.80 \\ fresh & & & & 0.36 & 1.33 & noticeable & noticeable \\
250 MPa-60 \({}^{\circ}\)C, & & & & barely & 2.34 & 1.99 \\ fresh & & & & noticeable & noticeable & noticeable \\ Control, & & & & & 2.06 & 1.71 \\
14 th day & & & & & noticeable & noticeable \\
60 \({}^{\circ}\)C-250 MPa, & & & & & 0.50 \\
14 th day & & & & & barely \\
250 MPa-60 \({}^{\circ}\)C, & & & & & noticeable \\
14 th day & & & & & & noticeable \\ \hline \hline \end{tabular}
\end{table} 
Table 4: \(\Delta\)E* colour difference values and its relationship between visual perception in the case of smoothie samples.