# Impact of Coconut Copra Byproducts Incorporation on Granola Quality Characteristics
## 2 Materials and Methods
### Water/Oil Absorption, Foaming and Emulsifying Capacity and Stability Characteristics  
Blends were prepared by combining coconut powder and banana flour in specific proportions to serve as granola ingredients. The tested ratios included 100% coconut powder (CC), a 1:1 ratio of coconut powder to banana flour (CC50/50 BF), and a 3:1 ratio of coconut powder to banana flour (CC75/25 BF). These formulations were selected to evaluate the functional properties of the individual components and their combinations.  
The techno-functional characteristics of the coconut copra (CC) and banana flour (BF) blends were analyzed to evaluate the water holding capacity (WHC), water absorption capacity (WAC), oil absorption capacity (OAC), hydrophilic-lipophilic index (HLI), water absorption index (WAI), water solubility index (WSI), and swelling power (SP). The WAC, OAC, and HLI were determined using a modified method previously described by [PERSON] et al. (2018) [18], with slight modifications. Specifically, 3 g of the blend was combined with 30 mL of distilled water (for the WAC) or rapeseed oil (for the OAC) in centrifuge tubes. After vortexing (30 s, [PERSON], Schwabach, Germany), the samples were centrifuged at 3000\(\times\)\(g\) (Thermo Fisher Scientific, Waltham, MA, USA), and the supernatants were decanted. Residual liquid was removed by heating tubes at 50 \({}^{\circ}\)C in an oven (Vindon Scientific, Rochdale, UK). The WAC and OAC values were expressed as g liquid/g dry samples. The HLI was calculated as the WAC/OAC ratio.  
The WAI, WSI, and SP were analyzed following the procedure described by [PERSON] et al. (2020) [19], with slight modifications. Each 3 g sample was dispersed in 30 mL of distilled water, placed in pre-weighed centrifuge tubes, and heated to 90 \({}^{\circ}\)C for 10 min in a water bath (MLL147, AJL Electronics, Krakow, Poland). Post-heating, the samples were cooled to room temperature, centrifuged at 3000\(\times\)\(g\) for 10 min, and the sediment was weighed. Supernatants were transferred to pre-weighed Petri dishes, dried at 110 \({}^{\circ}\)C for 24 h (SML, Zalmed, Lomianki, Poland), and analyzed to determine solid content. The WAI (g water/g dry solid), WSI (g water/100 g dry solid), and SP (g water/g dry solid) were calculated using established formulas [19].  
As previously described [17], foam capacity and stability (FC, FS) and emulsifying activity and stability (EA, ES) were evaluated. Briefly, the blend (1 g) was dispersed in  
Figure 1: Constituent parts of coconut fruit (_Cocos nucifera_).  
distilled water (50 mL) in a graduated cylinder, tapped, and shaken vertically by hand for 5 min. The initial and final volumes were noted, and the difference was expressed as the FC [mL/g DM]. The sample was left undisturbed for 1 h, and the final volume was recorded. The foam stability was calculated as [%] according to the following equation:  
\[\text{FS}\left[\%\right]=\text{(V1H/Vinitial)}\times 100 \tag{1}\]  
Emulsifying activity and stability (EA, ES) were measured by combining the sample with water and oil, homogenizing the mixture, and assessing the emulsion volume after centrifugation. Stability was further confirmed by reheating and allowing the emulsion to settle.