# Effect of Microwave-Assisted Processing of Acorn Flour on Muffin Quality
## 3 Results and Discussion
### Effect of Microwave-Treated Acorn Flour Addition on Technological Properties of Muffins  
Microwave treatment of acorn flour significantly influenced the technological quality characteristics of wheat-acorn muffins (Table 3). The volume and crumb structure of the muffins varied according to the power and duration of microwave exposure: Short microwave treatments resulted in increased muffin volume and crumb porosity while maintaining lower firmness; however, with extended treatment times, these parameters deteriorated. Moreover, higher microwave power levels further exacerbated the decline in these quality attributes. The volume of muffins containing dry microwave-treated flour was influenced by both the duration and power of microwave treatment. Higher volumes were observed in samples baked with flour subjected to shorter processing times and lower microwave power. The highest volumes were recorded for the sample with flour microwaved for 1.0 min at 925 W (82.64 cm\({}^{3}\)) and for 0.5 min at 1295 W (79.19 cm\({}^{3}\)). Prolonging the treatment time and increasing the power resulted in a reduction in muffin volume. Notably, only the sample treated for 3.0 min at 925 W exhibited a statistically significant decrease in volume compared to the control sample (a 5.8% reduction). The remaining samples either showed no statistically significant difference or demonstrated a higher volume than the control. The volume of muffins containing wet microwave-treated flour was lower than that of muffins with dry microwave-treated flour, although it was either not statistically signifiicantly different from or higher than the control. The only sample with wet microwave-treated flour that exhibited a volume lower than the control was the sample treated for 1.0 min at 1850 W (65.33 cm\({}^{3}\), an 8.4% reduction). As observed in the dry microwave-treated flour samples, longer processing times and higher microwave power resulted in a decrease in muffin volume. The porosity of muffins containing both dry and wet microwave-treated flour followed trends similar to those observed for volume. Longer processing times and higher microwave power resulted in reduced porosity, indicating a more compact crumb structure. When comparing samples treated at the same microwave power and duration, muffins containing wet microwave-treated flour exhibited lower porosity than those containing dry microwave-treated flour. Changes in porosity were also evident in the cross-sections of the muffins (Figure 2). In addition to porosity, which is expressed as the proportion of empty spaces within the crumb structure, the size and distribution of pores also changed. In muffins with dry microwave-treated acorn flour, larger and irregularly distributed pores appeared in the crumb structure compared to the control sample, leading to the formation of empty spaces. The effect of wet microwave-treated acorn flour on the structure and porosity of the crumb was more dependent on the microwave power used, detailed as follows: At 925 W, muffins exhibited uniform porosity. Higher microwave power led to uneven porosity in the crumb, which decreased further as the power and time increased. Samples with wet microwave-treated flour at 1850 W were characterized by a moist, compact crumb. Microwave treatment of acorn flour significantly influenced the firmness of the muffin crumb. Muffins containing flour treated with lower microwave power levels and/or shorter durations exhibited lower crumb firmness compared to the control. This reduction in firmness can be attributed to the higher porosity of the crumb, which, despite its increased volume, remains delicate and prone to deformation. In contrast, muffins made with flour subjected to higher microwave power and longer durations had a denser structure and increased firmness, requiring greater force for compression.