*3.1. Pasta Processing*

The addition of β-glucans, vital gluten, and xanthan gum affected the extrusion process of the pasta. The increasing content of β-glucans in the enriched pasta resulted in higher pressure values, compared to the control sample (Table 1). The dough was pushed through a dye under diminished pressure from 8.5 MPa for the control pasta to 13 MPa (BG0, BG5, BG10) and 13.5 MPa (BG15, BG20). The addition of gluten and xanthan gum caused a significant reduction in the efficiency of the pasta extruder. The formation of a strong gluten matrix caused by the addition of vital gluten and xanthan gum limited the flow rate of the dough through the forming holes in the die and thus reduced the extruder's efficiency. Additionally, the high water absorption of xanthan gum and gluten changed the consistency of the dough. It became harder and less plastic. The increase in the β-glucan content increased the plasticity of the dough. The relatively high content of soluble fiber and fat in this raw material made it difficult to build a strong protein-starch matrix in the dough. The flow rate of the dough through the holes in the matrix increased and, consequently, the extruder's performance increased. Pasta samples (uncooked and cooked) obtained in this study are shown in Figure 1.

**Figure 1.** Uncooked and cooked pasta samples. CON—control sample; BG—β-glucans.

### *3.2. Chemical Analysis*

The chemical composition of the raw materials and pasta samples is reported in Table 2. The high content of protein in semolina was responsible for the creation of the strong protein-starch matrix in pasta, which determined the cooking and product quality parameters [22]. In the case of pasta fortified with high-fiber raw materials, weakening of the gluten network and deterioration of cooking quality parameters were most often noted [17,49]. Therefore, vital wheat gluten was used in the β-glucan-fortified pasta samples. The addition of vital wheat gluten, which contained up to 71% protein, caused an increase in the protein content in the sample BG0 and in all samples with β-glucans, compared to the control sample. The addition of β-glucans significantly (*p* ≤ 0.05) affected the

chemical composition of the pasta. This raw material contained less protein than durum semolina; therefore, increasing the share of β-glucans from 0 to 20% at the expense of semolina led to a decrease in protein content. In addition, xanthan gum was added, which next to β-glucans was a good source of soluble dietary fiber [50]. At the same time, many studies have shown that a small addition of this component had a positive effect on the texture and sensory quality of cooked pasta [36–38,40,41]. As demonstrated by results presented by other authors, the addition of soluble dietary fiber (e.g., xanthan gum, guar gum) meant that, after hydration, non-starch polysaccharides surrounded the protein-starch network, reducing the loss of dry matter [38]. Along with the increase in β-glucans, the ash and fat content increased proportionally. The increase in the ash content resulted from the inclusion of the high-fiber raw materials (e.g., xanthan gum, β-glucans) in the product. The fat content was already high in the β-glucan preparation (Table 2). Both lipids and minerals had a positive effect on the cooking quality of pasta, increasing the stability of the starch-protein matrix [27]. Along with the increase in the share of β-glucans in the pasta, a significant (*p* ≤ 0.05) increase in the content of total fiber (TDF) and its soluble fraction (SDF) was noted. The values of TDF and SDF in the BG20 sample were more than four times and six times higher than the control sample, respectively. It should be emphasized that the addition of xanthan gum and gluten also caused a significant (*p* ≤ 0.05) increase in dietary fiber content in pasta. Enrichment of the product with β-glucans reinforced these trends. The addition of β-glucans caused a decrease in the share of digestible carbohydrates, which combined with a simultaneous increase in the content of the soluble fiber fraction, which could probably have an impact on reducing the glycemic index of pasta. Soluble fiber (β-glucans) competed with starch granules for water availability and reduced swelling and gelation of starch. As a result, its digestibility and availability decreased [28]. The glycemic index of the product was mainly influenced by the soluble fraction of dietary fiber. It increased the viscosity of the chyme, hindered the access of amylolytic enzymes to starch, reduced the dynamics of starch digestion, and created a sticky film on the intestinal surface impeding glucose absorption into the bloodstream. What is more, fiber stimulated the production of short-chain fatty acids (SCFA) that formed as a result of bacterial fermentation in the large intestine. These acids absorbed by colonocytes through the portal vein entered the liver, where they regulated the metabolism of fatty acids and cholesterol. Propionic acid was of particular importance, as it inhibited the synthesis of fatty acids that reached the bloodstream and regulated adipocytokines (adipokines), i.e., proteins responsible for *inter alia*, glycemic homeostasis, and lipidemia [10].
