## 3 Results and Discussion
### The Techno-Functional Properties of Proteins
#### 3.2.4 Particle Size Distribution  
Since droplet size and dispersion influence possible coalescence processes, they rank among the most significant features of emulsions. Therefore, they can be utilized as a stand-in for stability [33]. The application of HIU promotes changes in the \(d_{3,2}\), \(d_{4,3}\), and the PDI; for the modified proteins, the most important reduction in the indexes' values were acquired at 1080 W and 15 min, contributing to a monomodal distribution (Figure 2). The potential flocculation or coalescence of an emulsion can be determined by using the \(d_{4,3}\) index, owing to its sensitivity to determine the presence of larger droplets; high values suggest a more unstable emulsion [34,35]. On the other hand, the \(d_{3,2}\), which indicates the mean diameter at which most of the particles fall, is inversely proportional to the specific surface area of droplets [34]. The increment in the PDI could be related to the pressure in the microbubbles caused by cavitation phenomena, as this value increases as the system heterogeneity also does [36]. From the standpoint of thermodynamics, small droplets and low values of the mentioned parameters favor the system's stability [33]. The acoustic field  
Figure 2: Particle size distribution of manufactured emulsion with leaf jackfruit protein treated by high-intensity ultrasound (60, 840, and 1080 W for 10, 15, and 20 min). created by HIU waves separates the dispersed from the continuous phase. Additionally, the pressure variations caused by the cavitation compress microbubbles into micro- or nano-sized droplets, reducing the possibility of destabilizing the processes of cream production and coalescence in the system [36; 37]. In addition to this, it was previously reported that the concentration of particles also plays a vital role in the emulsion stability. In dilute emulsions, smaller particles enhance stability against droplet coalescence, whereas larger particles can improve droplet stability at high-volume fractions of the dispersed phase. This suggests that the dynamics of droplet interactions differ significantly in concentrated emulsions compared to dilute systems [38]. Surfactants, such as Tween 80, are used to stabilize the droplets during emulsification and, thus, prevent the coalescence of the droplets [39]. The particle size distribution also can be affected by the molecular weight (Mw) distribution of modified proteins from jackfruit leaf. As the duration of the HIU treatment increases, the Mw distribution of jackfruit leaf protein hydrolysates could shift to a small size. Significative reductions in the Mw by HIU have been reported in modified proteins from egg white (from 124.24 to 60.52 nm, after 15 min of treatment at 800 W, 20 kHz, and an amplitude of 30%) [40; 41]; sunflower protein isolates (from 114.6 to 93.6 nm, after 30 min of treatment at 500 W, 20 kHz, and an amplitude of 25%) [42]; and in sesame protein isolates (after 6 min of treatment 20 kHz and at a 95% amplitude) [43]. These results may be linked to the acoustic cavitation effects generated by the US, which disrupt the protein structure [44]. The changes in Mw distribution are closely related to the functional properties of the modified proteins. For instance, an increased sonication time has been associated with the enhanced solubility and emulsifying properties of the modified proteins. This is because smaller modified proteins generally exhibit better solubility, hence they can stabilize emulsions more effectively than larger protein aggregates [1]. Another key factor is the concentration of the polymers in the emulsion. It has been demonstrated that the application of US (200 W for 30 s) in double emulsions based on poly (lactic acid) (60, 90, 120, and 150 mg) and pilocarping (24, 36, 48, and 60 mg) helps to obtain a homogeneous particle size distribution. However, as the concentration of the polymers increased, the shell thickness increased from 10 to 99 nm, reducing the encapsulation efficiency from 93 to 52%.