## 3 Results
### Physical Properties of Corn-Based Crisps Supplemented with Fruits
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Fruit** & **Screw Speed** & **EI [-]** & **BD [kg/m\({}^{3}\)]** & **WAI [g/g]** & **WSI [\%]** \\ \hline \multirow{4}{*}{5} & 80 & 3.48 \(\pm\) 0.07 & 58.31 \(\pm\) 0.21 & 5.57 \(\pm\) 0.01 & 18.10 \(\pm\) 1.35 \\  & 100 & 3.85 \(\pm\) 0.03 & 53.65 \(\pm\) 0.15 & 5.55 \(\pm\) 0.07 & 19.05 \(\pm\) 0.67 \\  & 120 & 3.78 \(\pm\) 0.07 & 49.10 \(\pm\) 0.37 & 5.41 \(\pm\) 0.05 & 20.00 \(\pm\) 1.17 \\ \hline \multirow{4}{*}{10} & 80 & 3.05 \(\pm\) 0.05 & 93.22 \(\pm\) 0.48 & 5.19 \(\pm\) 0.12 & 16.19 \(\pm\) 2.69 \\  & 100 & 2.75 \(\pm\) 0.03 & 99.44 \(\pm\) 0.26 & 4.94 \(\pm\) 0.06 & 16.67 \(\pm\) 0.67 \\  & 120 & 2.82 \(\pm\) 0.13 & 79.41 \(\pm\) 0.48 & 4.90 \(\pm\) 0.19 & 17.14 \(\pm\) 1.17 \\ \hline \multirow{4}{*}{15} & 80 & 1.80 \(\pm\) 0.04 & 188.84 \(\pm\) 0.68 & 3.61 \(\pm\) 0.03 & 18.10 \(\pm\) 1.35 \\  & 100 & 1.81 \(\pm\) 0.03 & 180.59 \(\pm\) 0.30 & 3.56 \(\pm\) 0.04 & 17.62 \(\pm\) 1.78 \\  & 120 & 1.76 \(\pm\) 0.06 & 184.82 \(\pm\) 0.37 & 3.41 \(\pm\) 0.01 & 17.14 \(\pm\) 0.00 \\ \hline \multirow{4}{*}{20} & 80 & 1.58 \(\pm\) 0.02 & 206.79 \(\pm\) 1.47 & 2.78 \(\pm\) 0.02 & 20.95 \(\pm\) 0.67 \\  & 100 & 1.55 \(\pm\) 0.06 & 189.33 \(\pm\) 1.28 & 2.76 \(\pm\) 0.00 & 20.00 \(\pm\) 0.00 \\ \cline{1-1}  & 120 & 1.54 \(\pm\) 0.03 & 188.73 \(\pm\) 0.51 & 2.61 \(\pm\) 0.02 & 19.52 \(\pm\) 0.67 \\ \hline \end{tabular} El—expansion index; BD—bulk density; WAI—water absorption index; WSI—water solubility index; results are presented as mean \(\pm\) standard deviation.  
\end{table} 
Table 4: Physical properties of corn-based crisps supplemented with white mulberry powder. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Fruit** & **Screw Speed** & **EI [-]** & **BD [kg/m\({}^{3}\)]** & **WAI [g/g]** & **WSI [\%]** \\ \hline \multirow{4}{*}{5} & 80 & 3.93 \(\pm\) 0.03 & 48.34 \(\pm\) 0.56 & 5.73 \(\pm\) 0.04 & 18.10 \(\pm\) 1.78 \\  & 100 & 4.14 \(\pm\) 0.26 & 43.86 \(\pm\) 0.20 & 5.58 \(\pm\) 0.02 & 20.48 \(\pm\) 0.67 \\  & 120 & 3.85 \(\pm\) 0.24 & 45.56 \(\pm\Application of dried apple caused limitation of crisps expansion and lowered BD (Table 3) due to fibers and pectins replacing the starch in the recipe. Lowering the expansion was more significant with increasing apple powder addition. When 20% of dry apples were added, EI decreased to around 70%, as compared to control crisps. Limited expansion also significantly affected the bulk density of the supplemented crisps. BD was similar to control at only 5% of apple powder supplementation. Higher amounts increased mass of the same volume of product because it became less aerated and formed a denser structure. Maximum bulk density was 261.06 kg/m\({}^{3}\) if 20% of apple powder was used. Screw speed had only a slight effect, confirming the statistical analysis of the weak effect of screw speed on the tested physical properties (Table 2). WAI and WSI values were lowered if apple powder content increased in the recipe (Table 3), and water absorption of samples with 5% of apple powder alone was slightly higher than the control. This may be the effect of limiting the starch content in recipes, especially with high levels of additive, and thus replacing starch by the pectins and fiber present in dry apples [19]. These results confirm the lower ability to absorb water [29], but the effect can be considered positive as it results in lower solubility of components into liquids such as water or milk. Hence, the addition of powdered apple in amount from 10 to 20% may be desired for extruded breakfast cereals instead of crisps, as the product will not lose extrudates components into the applied milk, juice or yoghurt. Table 4 present the results of physical properties of crisps supplemented with white mulberry powder. A similar range of expansion index values were found in snacks with white mulberry addition (Table 4) as if apple powder (Table 3) was used.