The values correspond to means ± deviations and are expressed in (g/100 g db), n = 3; \* mg/100 g db. Different letters in each row are significantly different (*p* < 0.05).

#### *3.2. Performance Parameters and Nutritional Composition*

The mass yield, protein recovery, and chemical and nutritional composition of hydrolyzed flours are shown in Table 1. HBF had higher mass yield and protein recovery than HQF (*p* < 0.05) due to their higher natural bean protein content; this agrees with the results found by Thamnarathip et al. [9]. The high protein content of hydrolyzed flours (>50%) makes them useful to be incorporated into sports foods. Soluble dietary fiber (SDF) content was significantly different (*p* < 0.05) between both hydrolyzed flours.

Na and K were the most abundant minerals in both hydrolyzed flours, both necessary for the replacement of electrolytes lost during physical training [10]. According to Xia et al. [10], minerals such as Fe, Zn, and Mg also stand out for their usefulness for an athlete's nutrition. A portion of 30 g of these hydrolyzed flours would contribute between 73% to 76% of the recommended protein dose (20–25 g) to stimulate muscle protein synthesis after exercise [1]; 12–25% of suggested fiber dietary intake (25–30 g/day); approximately 48–62% and 53–60% of Na and K RDI, respectively, for athletes.

Table 2 shows the total and free amino acid composition of hydrolyzed flours. The total essential amino acid content was 6415.13 and 11901.71 mg/100 g of HQF and HBF, respectively. The predominant essential amino acids were leucine, lysine, and valine; these results agree with Muhamyankaka et al. [2]. HBF and HQF presented high contents of branched amino acids, essential in sports nutrition to improve sports performance by reducing the appearance of fatigue. Both hydrolyzed flours are rich in glutamic acid, glutamine precursor, which is important to recover muscle glycogen deposits and avoid loss of muscle mass.




**Table 2.** *Cont.*

<sup>a</sup> Total amino acid content, <sup>b</sup> Free amino acid content, <sup>c</sup> Umami taste: Glu + Asp; Sweet taste: Ala + Arg + Ser + Thr; Bitter taste: Gly + His + Ile + Leu + Met + Phe + Val + Pro; n.d: not detected.

HBF was rich in free arginine (38.88%) and aspartic acid (18.69%), while HQF was rich in free phenylalanine (13.60%), alanine (10.80%), histidine (10.57%), and leucine (9.02%); these results are similar to those found by Laohakunjit et al. [11]. The free amino acids would significantly affect the taste characteristics of hydrolyzed flours. HBF had the highest amount of umami and sweet amino acids, whereas HQF had the highest content of bitter amino acids.

#### *3.3. Functional Properties*

Protein solubility. Figure 1 shows HBF and HQF protein solubility. HBF showed significantly higher solubility and a greater range of variation with the pH (65.10–87.54%) than HQF (*p* < 0.05). The minimum protein solubility was at pH 4 (16.22 and 33.77% for HBF and HQF, respectively). The higher protein solubility in HBF could be due to its greater exposure of polar amino acid that interacts with water through hydrogen bonding. The inconsistency between the lower DH and higher solubility in HBF could be due to the balance between hydrophilic and hydrophobic forces scores over DH.

**Figure 1.** Protein solubility of HBF () and HQF (•) as a function of pH.

Emulsifying properties. HQF presented better surfactant properties than HBF (*p* < 0.05) (Table 3). The lower EAI and ESI values in HBF could be due to the lower DH and a higher exposure of hydrophilic groups that would bind with peptides in the aqueous phase, decreasing hydrophobicity and emulsifying stability [12].


**Table 3.** Functional properties of HBF and HQF.
