# Hybrid Heat Products: Incorporation of White Bean Flour in Lean Pork Burgers
## 3 Results and Discussion
### Physicochemical Properties

Table 2: Regression coefficients of the proposed model for the variables: process yield, texture variables (hardness, cohesiveness, springiness, chewiness, resilience), and color parameters (L* and b*) expressed in terms of the coded level of the bean flour (BF) and water/bean flour ratio (W/BF) in the BF-burgers. Statistical significance of the models (P), lack of fit, and “adequate precision” coefficient, are also included. As can be seen in the coefficients in Table 2, the behavior of hardness and cohesiveness was controlled both by the main effects of the W/BF ratio and BF content and also by the interaction between them, with coefficients higher in magnitude for hardness. Therefore, hardness and cohesiveness response surfaces showed similar trends concerning the ingre  
Figure 1: Contour plots of the variation of **(a)** process yield (g/100 g); **(b)** hardness (N); **(c)** cohesiveness; **(d)** springiness; **(e)** chewiness (N); **(f)** resilience; **(g)** lightness (L*); **(h)** yellowness (b*), as a function of bean flour (BF) level (g/100 g) and water/bean flour ratio (W/BF) of BF-burgers. Darker colors indicate lower values of the modeled responses. dient levels (Figure 1b,c): the 3D surfaces plot showed that both parameters decreased as BF level increased, with a more noticeable effect when the W/BF ratio became larger. This effect was previously observed when different pulse flours were used in pork burgers [18]. These results were consistent with studies that had shown that some meat substitutes resulted in minced meat products with better texture characteristics because they were dissolved in the meat protein matrix, absorbed water, and resulted in softener products [26; 27]. In this sense, [PERSON] et al. [28] attributed the softening of beef burgers to the rapid hydration of the lentil flour particles with low density. When analyzing the different BF-burgers, a very good positive correlation was observed between pork meat content and hardness (R\({}^{2}\) = 0.85). However, when evaluating the hardness of the C-B, a drastic reduction in its value was observed that did not fit to previous regression for the other burgers (Figure 2a). The spatial arrangement of the fibers is of utmost importance for the textural behavior of the meat. Minced meat is constituted by disintegrated muscle bundles and fibers of different sizes. These components are arbitrarily scattered in the matrix together with cracks between them, and are held together by the extracted myofibrillar mass [24]. Thus, the differences between BF-B and C-B hardness could be attributed to a structural change in the matrix. It could be inferred that the BF components would be interacting with the meat proteins, reinforcing the meat gel. A similar result was obtained by [PERSON] et al. [29], who found significantly higher values of hardness when pigeon pea flour was added to sausages, and [PERSON] et al. [30], who reported that the addition of fiber increased the hardness in comparison to controls with only meat. On the other hand, the cohesiveness of the C-B showed a higher value than those observed in BF-B (Figure 2b). This could imply that although the interaction between the meat proteins and the flour components could increase the hardness, it would reduce the tighter connections that occurred among meat particles, leading to a less dense and uniform structure, decreasing the burger's cohesiveness [31]. Similar results were found with rice bran fiber that significantly decreased the cohesiveness of a meat system [32] and with quinoa seed flour in goat meat nuggets [33]. Concerning chewiness, springiness, and resilience, linear models were fitted (Table 2). The three parameters were negatively correlated with BF level and W/BF ratio, but among them, chewiness showed a larger dependence on both factors. Regarding color parameters, lightness (L*) was dominated by the BF level, the W/BF ratio, and also the interaction between them, while for the yellowness (b*), the interaction was not significant.