# Effect of Ultrasonic Treatment on the Quality of Pumpkin Juice Fermented by Yeast
## 3 Results
### Analysis of the Interaction Effects of Various Factors on the Sensory Evaluation of Pumpkin Juice  
The regression equation was obtained using DesignExpert-8.0.6 software, and a series of response surface plots and contour plots were drawn, as shown in Figure 1, to conduct a study on the sensory evaluation of pumpkin juice, analyzing the influence of the interaction effects of various factors on the sensory evaluation. The slope of the response surface reflects the degree of influence of each factor on the sensory evaluation value. The steeper the slope, the greater the influence of the factor on the sensory evaluation. In the interaction plot between the content of pumpkin juice and the inoculation amount of yeast (Figure 1A), the change in the slope of the response surface can be observed to determine the strength of the influence of the two on the sensory evaluation. Similarly, in the interaction plots between the content of pumpkin juice and the fermentation time (Figure 1C), and between the content of pumpkin juice and the temperature (Figure 1E), the influence magnitude of the corresponding factors can be analyzed through the slope of the response surface. The shape of the contour lines reflects the degree of interaction between the factors. Elliptical contour lines indicate an obvious interaction effect, and the closer the shape is to a circle, the less significant the interaction effect. Observe the shapes of the contour lines in the interaction plots, such as between the content of pumpkin juice and the inoculation amount of yeast (Figure 1B), between the content of pumpkin juice and the temperature (Figure 1F), and between the content of pumpkin juice and the fermentation time (Figure 1D), to determine whether the interaction effect between the factors is obvious. For example, if the contour lines are elliptical, it indicates that the interaction effect of the corresponding two factors has a greater influence on the sensory evaluation; if they are close to a circle, the interaction effect has a smaller influence. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Source of** & **Sum of** & **Degrees of** & **Mean** & **F Value** & \(p\) **Value** \\
**Variance** & **Squares** & **Freedom** & & & \\ \hline Model & 25.53 & 14 & 1.82 & 19.01 & \textless{}0.0001 \\ A & 0.19 & 1 & 019 & 1.95 & 0.1838 \\ B & 0.03 & 1 & 0.03 & 0.31 & 0.5848 \\ C & 16.33 & 1 & 16.33 & 170.29 & \textless{}0.0001 \\ D & 0.021 & 1 & 0.021 & 0.22 & 0.6483 \\ AB & \(3.553\times 10^{-15}\) & 1 & \(3.553\times 10^{-15}\) & \(3.704\times 10^{-14}\) & 1 \\ AC & 0.01 & 1 & 0.01 & 0.1 & 0.7516 \\ AD & 0.56 & 1 & 0.56 & 5.86 & 0.0296 \\ BC & 0.062 & 1 & 0.062 & 0.65 & 0.433 \\ BD & 0.022 & 1 & 0.022 & 0.23 & 0.6356 \\ CD & 0.3 & 1 & 0.3 & 3.15 & 0.0975 \\ A\({}^{2}\) & 6.58 & 1 & 6.58 & 68.64 & \textless{}0.0001 \\ B\({}^{2}\) & 0.02 & 1 & 0.02 & 0.2 & 0.658 \\ C\({}^{2}\) & 0.34 & 1 & 0.34 & 3.58 & 0.0794 \\ D\({}^{2}\) & 0.075 & 1 & 0.075 & 0.78 & 0.3916 \\ Residual & 1.34 & 14 & 0.096 & & \\ Lack of Fit & 1.13 & 10 & 0.11 & 2.13 & 0.2421 \\ Pure Error & 0.21 & 4 & 0.053 & & \\ Cor Total & 26.87 & 28 & & & \\ R\({}^{2}\) & 0.9500 & & & & \\ R\({}^{2}\)\({}_{\text{Adj}}\) & 0.9000 & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Response surface test results. 3.1 Influence of the Interaction Between the Content of Pumpkin Juice and the Temperature on the Sensory Evaluation of Pumpkin Juice  
Figure 1A shows the influence of the interaction between the content of pumpkin juice and the temperature on the sensory evaluation. When the fermentation temperature is constant, the sensory evaluation score first increases and then decreases with the increase in the content of pumpkin juice, indicating that there is a certain content of pumpkin juice at which the sensory evaluation score reaches the maximum.