## 3 Results and Discussion
#### 3.1.2 Reducing Sugars and Antioxidant Characteristics
As a result, the prepared and tested mixtures of these two raw materials, such as luffa powder and tapioca flour, present significant potential as a raw material for the preparation of functional products with significant antioxidant properties. The strong broad band, at ca. 3280 cm\({}^{-1}\) in the _Luffa cylindrica_ seed press cake and its blends with cassava flours (Figure 4), correspond to the free hydroxyl groups' stretching \(\upsilon\)(OH) mode and those involved in the intra- and inter-molecular hydrogen bonds (HB). The spectra show several distinct absorption regions characterizing the samples' molecular composition. The FT-IR/ATR analysis suggests a medium lipid content in the seed press cake and flour blends. This is evidenced by sharp bands of medium intensity at the following wavenumbers: 3008 \(\
u\)(=C-H)/cis, 1744 (\(\
u\)(C=O)), 1456 (\(\delta\)(CH)/CH2), 1414 (\(\rho\)(=CH)/cis), 1149 (\(\
u\)(C-O), \(\delta\)(CH-2)), 707 (\(\rho\)(-(CH2)n-), and \(\rho\)(C=C)/-, cis) cm\({}^{-1}\)[56]. The intense vibration at 1638 and 1536 cm\({}^{-1}\) can be attributed to the amide I (\(\
u\)(C=O), \(\delta\)(N-H)) and II (\(\delta\)(N-H), \(\
u\)(C-N)) bonds from the protein compounds [57]. This indicates the cake's high protein content and the blends' beneficial fortification. The characteristic symmetrical and asymmetrical -C-O-C vibrations for carbohydrates in the 1100-900 cm\({}^{-1}\) range are observed [56]. Adding more of the cakes to the flour has a positive effect on the nutritional properties of the mixture, i.e., it increases the concentration of proteins and unsaturated fats at the expense of starch. The FTIR spectra present the molecular fingerprints of _L. cylindrica_ seed press cake powder and its blends with cassava flour at different ratios: E1 (50/50%), E2 (30/70%), and E3 (70/30%). This reveals the characteristic functional groups and their interactions across the 4000-600 cm\({}^{-1}\) spectral range. In the high-frequency region (3500-3000 cm\({}^{-1}\)), all samples exhibit a broad absorption band centered at approximately 3280 cm\({}^{-1}\), corresponding to O-H stretching vibrations from hydroxyl groups involved in intra- and intermolecular hydrogen bonding. The pure _L. cylindrica_ seed press cake (L) shows a relatively sharp and intense peak, while the blends  
Figure 4: The FT-IR/ATR spectra of _Luffa cylindrica_ seed press cake powder (L) and its blends with cassava flours (E1, E2 and E3). (E1, E2, E3) display broader bands with varying intensities, indicating different degrees of hydrogen bonding networks between the seed press cake and cassava flour components. The region between 2800-3000 cm\({}^{-1}\) shows distinct peaks at 2925 and 2854 cm\({}^{-1}\), attributed to the asymmetric and symmetric C-H stretching vibrations of methylene (CH\({}_{2}\)) groups. These peaks appear most prominently in pure _L. cylindrica_ seed press cake, suggesting a higher lipid content, with the peak intensity decreasing in the blends proportionally to the seed press cake content. A significant peak at 1744 cm\({}^{-1}\) is observed across all samples, corresponding to the C=O stretching vibrations of ester groups, likely from residual oil or lipid components in the seed press cake. The intensity of this peak is highest in pure seed press cake and decreases systematically in the blends (E3 \(>\) E1 \(>\) E2), correlating with the seed press cake content. The prominent bands at 1638 and 1536 cm\({}^{-1}\) can be attributed to amide I and amide II vibrations, respectively, indicating substantial protein content in the seed press cake. These peaks show C=O stretching and N-H bending vibrations characteristic of protein secondary structures. The intensity of these protein-related peaks decreases with the reduced seed press cake content in the blends. The fingerprint region (1500-900 cm\({}^{-1}\)) reveals complex overlapping peaks characteristic of carbohydrate structures.