## 2 Results and Discussion
### Cooking Properties  
Cooking quality is an important attribute affecting consumer acceptance. The cooking properties of the investigated pasta products are shown in Table 2. In terms of optimal cooking time (OCT) and cooking losses, C and B5 pasta were very similar. Pasta B2.5 had significantly shorter OCT and higher values of cooking loss. A decreasing trend was observed in terms of water absorption; however, the differences were not statistically significant. Control pasta had a significantly lower swelling index (SI) compared to BLP- fortified pasta.  
In this study, the OCT varied between 3.0 and 3.6 min, which is a relatively small range. Incorporation of BLP resulted in a reduction in OCT, which can be explained by the high water absorption index of freeze-dried BLP [27]. Significant changes were observed only in pasta B2.5, probably due to higher moisture content and, consequently, faster rehydration. Similar results were observed by [PERSON] et al. [11], who reported that pasta fortified with onion skin powder had a shorter OCT compared to control pasta. [PERSON] et al. [3] reported that the OCT of fresh pasta enriched with concentrations of broccoli up to 30% varied between 2.5 and 4.5 min, which is a wider range than that observed in this study. Water absorption also decreased with the addition of BLP, although the differences were not statistically significant. This could be attributed to shorter cooking times, which can reduce the water absorption of pasta [11].  
\begin{table}
\begin{tabular}{c c c c} \hline \hline  & **C** & **B2.5** & **B5** \\ \hline Semolina [g] & 400.0 & 400.0 & 400.0 \\ Water [g] & 140.0 & 140.0 & 140.0 \\ Olive oil [g] & 15.0 & 15.0 & 15.0 \\ Salt [g] & 2.0 & 2.0 & 2.0 \\ BLP [g] & 0.0 & 10.0 & 20.0 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Formulations of control and fortified pasta. C (control pasta); B2.5 pasta fortified with 2.5% broccoli leaf powder; B5 (pasta fortified with 5% broccoli leaf powder).  
Another parameter defining cooking properties analysed in this study is cooking loss. Cooking loss represents the amount of solid material lost in the cooking water and is one of the most important parameters determining the quality of pasta [10]. In this study, the highest cooking loss was observed for B2.5 pasta, whereas control and B5 had significantly lower cooking losses. Importantly, none of the experimental pasta exceeded the technologically acceptable limit of 8% [10], indicating that incorporation of BLP into pasta does not decrease the quality of pasta. [PERSON] et al. [11] reported that cooking losses remained below 8% for pasta fortified with 2.5%, 5% and 7.5% onion by-product. These findings suggest that adding vegetable by-products in these concentrations might be a good option to enrich pasta products with vegetables without compromising pasta quality. In contrast, the incorporation of fruit by-products, namely 5% mango peel powder, resulted in cooking losses of more than 8%, which could result from the high sugar content in mango peel powder itself [28].  
SI of pasta is a good indicator of the integrity of the protein matrix, which restricts water penetration and depends on competition between the starch and protein for water absorption [5; 6]. In this study, pasta C had the lowest SI among all analysed pasta. The addition of BLP did not inhibit the swelling of the starch granules, but it seems that BLP contributed to the formation of a protein network, which increased the supply of water for swelling and gelatinisation of starch granules. A previous study showed that the incorporation of protein into the pasta formulation resulted in a reduction in SI [6]. On the other hand, some studies reported a significant increase in the SI with increased concentrations of dietary fibre [29]. Although the content of dietary fibre was not evaluated in this work, based on the results of a previous study reporting high content of dietary fibre in broccoli leaves [27], it can be assumed that it could also affect the SI of experimental pasta.