## 3 Results and Discussion  
### Production Rate of Spinning  
The different blends of the spinning solutions, each having a different protein content between 0.05 and 0.2 g/mL respectively, are further referred to as A, B, C, and D (Table 1). To compare the yield of the different spinning solutions, the production rates during spinning were measured by stopping the time and subsequently weighing the produced fibers. The production rates of the different blends with their ratios are listed in Table 1. The significantly highest production rate was achieved with blend B (5.78 \(\pm\) 0.4 g/h), whereas at the highest protein content (blend D), the production rate significantly decreased to 2.77 \(\pm\) 0.5 g/h. The comparison of the production rates of the blends B, C, and D shows that the production rate decreased with increasing protein content. Blend A shows a production rate of 3.42 \(\pm\) 0.17 g/h.  
An attempt was also made to spin a fifth solution, varying only in the protein content, which was set to 0.25 g/mL. The maltodextrin concentrations were the same as for the other blends. At this protein concentration, the dispersion was impossible to spin because too much foam formed overnight, which was probably caused by the high protein content of the spinning solution.  
In some instances, the production rates showed high standard deviations. This could be explained by the fact that during the spinning process the temperature and the RH could not be kept completely constant. Temperature and humidity influence the spinnability and duration of the spinning process and therefore the productivity [31]. High ambient temperatures and low RH lead to rapid evaporation of the solvent, which was why the solution could not be spun for the desired length of time. The viscosity of the spinning solution can also influence the spinnability and production rate. [PERSON] et al. found that as the protein concentration of the spinning solution increases, high viscosity inhibits spinnability [32]. The formation of Taylor cones is retarded and thus the spinning process is delayed [33]. This might be a possible explanation for the decreasing yield with higher protein contents.  
The spinning solution of blend A was visibly less viscous than the others. This may have caused the solution to drip from the spinneret roll during the spinning process which would explain the low production rate. The biopolymer solution should have a concentration high enough to cause biopolymer entanglement to allow the formation of the fibers [32]. In a recent study, an entanglement concentration between 0.21 and 0.29 g/mL was analyzed and for electrospinning three times higher concentration of the maltodextrin DE2 (0.8 g/mL) was applied [22]. The polymer chain entanglements within the jets prevent them from breaking up during spinning. If the polymer concentration is too low, no chain overlaps can form [18; 22]. At low viscosity, the degree of entanglement in the solution is too low and the resulting polymer jets are not very strong which causes them to easily break, thus interrupting the spinning process [33].  
[PERSON] et al. reported that in needle spinning, the mass rate of fiber production of the single jet lies typically between 0.1 and 1.0 g/h, but with needleless spinning producing several jets at the same time, much higher fiber yields can be obtained [34] which corresponds with the present results shown in Table 1.