# Influence of Plant-Based Structuring Ingredients on Physicochemical Properties of Whey Ice Creams
## 3 Results and Discussion
### Rheological Characteristics  
The viscosity of ice cream is a crucial factor in achieving the desired consistency of the final product. An increase in the ice cream viscosity hinders the ice crystal growth rate during recrystallization [43]. It depends on the solid content, especially fat, and the distribution of substances within the protein-carbohydrate matrix. Investigating the dynamics of viscosity changes in ice cream mixes under varying intensities of a disruptive force allows for a better understanding of the specificities of the freezing process. During this phase, the structuring of mixes is significantly diminished, but is partially restored after the formation of ice cream portions, thereby influencing the final quality of the product. Figure 1 displays the whey-based ice cream viscosities. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Sample No.**} & **Total Solid** & **Protein** & **Fat** \\  & **(\%)** & **(\%)** & **(\%)** \\ \hline
1. & \(24.05\pm 0.53\) a & \(0.75\pm 0.01\) a & \(0.51\pm 0.01\) a \\
2. & \(24.81\pm 0.28\) a & \(0.79\pm 0.01\) a & \(0.52\pm 0.01\) a \\
3. & \(24.57\pm 0.55\) a & \(0.76\pm 0.02\) a & \(0.51\pm 0.01\) a \\
4. & \(29.53\pm 0.40\) a & \(2.41\pm 0.09\) b & \(0.55\pm 0.02\) a \\
5. & \(31.02\pm 0.51\) c & \(3.23\pm 0.12\) a & \(0.55\pm 0.01\) a \\
6. & \(29.38\pm 0.46\) a & \(2.39\pm 0.05\) b & \(0.59\pm 0.02\) a \\
7. & \(31.16\pm 0.11\) c & \(3.18\pm 0.13\) c & \(0.54\pm 0.02\) a \\
8. & \(29.32\pm 0.59\) a & \(2.30\pm 0.07\) a & \(0.58\pm 0.01\) a \\
9. & \(30.95\pm 0.52\) b & \(3.28\pm 0.04\) c & \(0.61\pm 0.01\) a \\ \hline \hline \end{tabular} a–c—mean values denoted by different letters in the column differ significantly at \(p\leq 0.05\).  
\end{table} 
Table 2: Chemical composition of ice cream mixes. Figure 1 shows that the control ice cream had a low viscosity, which can be attributed to its relatively low solid content (Table 2). The addition of \(\beta\)-glucan, either from oat or yeast, to the control mix resulted in a notable increase in the viscosity of the resulting ice creams (sample 2-3). This is a common characteristic of water-soluble polysaccharides, attributed to the restricted mobility of their molecules [44]. The highest viscosity value was achieved with the combination of 0.4% Vianoks C45 + 3% WPC + 10% beet (sample 4). This outcome may be related to the structural changes resulting from the formation of metal complexes between Mn\({}^{2+}\) ions in enriched whey and pectin substances in beet puree [45]. Thus, the higher viscosity of the beet ice cream, among the samples containing vegetable purees, may be attributed to the larger pectin content in beet compared to that in zucchini and broccoli [46]. It is interesting to note that yeast-derived \(\beta\)-glucan ice cream (sample 3) also exhibited a substantial viscosity increase. Although scientists primarily consider this polysaccharide as a biofortifier [47], these results suggest that it is also an effective thickener and stabilizer. [PERSON] and [PERSON] [48] proved that \(\beta\)-glucan from baker's yeast plays a pivotal role in structuring low-fat yoghurt mixes, providing the desired viscosity and influencing the product's taste. Compared to oat \(\beta\)-glucan, which is known for its pseudoplastic behavior in dairy systems and can lead to excessive product density [7], yeast-derived \(\beta\)-glucan forms a gel network with moderate strength. These unique properties make yeast-derived \(\beta\)-glucan particularly intriguing for further exploration in ice cream production, especially concerning the freezing process where the mix becomes saturated with air. The lowest viscosity values were obtained for the zucchini ice creams (samples 8, 9), suggesting its limited ability to form structures. Finally, increasing the protein complex content to 4.5% led to a decrease in viscosity for all ice creams.