## 3 Results and Discussion
### Techno-Functional Properties of Insect Powders  
Water and oil holding capacities are important techno-functional properties related to a powder's ability to retain water and oil molecules [56]. These properties are crucial in determining the powder's potential use in food applications. It could be expected that the increased surface area from the finer particles produced by IR-CD would lead to a higher WHC. However, no significant differences in WHC were observed among the black soldier fly powders, as shown in Figure 3. It can be assumed that thermal and mechanical stresses associated with the IR-CD drying could have induced protein denaturation. Often, denatured or partially denatured conformations are prone to aggregate formation because they expose the protein's hydrophobic core to solvent [67], which can limit water absorption despite an increased surface area. Moreover, the OHC for CD powder was significantly lower than the IR-CD sample. Differences in OHC between powders processed by CD and IR-CD method may be influenced by surface properties. The greater fragmentation of the IR-CD sample may affect the OHC by increasing the number of oil-holding sites.  
Various values of WHC and OHC for edible insect powders have been reported [68; 4; 69]. For example, studies on the yellow mealworm (_Tenebrio molitor_) and house cricket (_Acheta domesticus_) powders showed WHC values of 1.62 g/g and 1.76 g/g, respectively, while the OHC values were 1.58 g/g and 1.42 g/g [70]. Comparing these values with the results obtained for black soldier fly larvae powders, it can be observed that both WHC and OHC were slightly lower. Although WHC remained unchanged, the OHC was impacted, which suggests that the drying methods may have selectively altered the functional properties of the powder. A high WHC improves texture and moisture retention in food products, enhancing their sensory properties and consumer acceptability. Insect powders with elevated WHC are particularly suitable for applications in soups, sauces, and bakery formulations, where moisture retention is crucial for product stability and quality [4]. Similarly, a high oil-holding capacity OHC plays a key role in flavor retention and mouthfeel by facilitating the binding of oils, which are carriers for lipophilic flavor compounds. Insect powders exhibiting high OHC are well-suited for incorporation into meat analogs, baked goods, and emulsified products [27]. Differences in WHC and OHC between insect  
Figure 3: The water-holding capacity (WHC) and oil-holding capacity (OHC) of black soldier fly powders processed by convective (CD) and infrared convective (IR–CD) drying methods. The same letters above columns (small letters for WHC, capital letters for OHC) indicate no differences between the mean values (\(t\)-test, \(p<0.05\)).  
powders may result from protein, fat, and chitin content. Insect powders are recognized for their high protein content, which is important in determining their WHC and OHC. For example, house cricket and yellow mealworm powders contain approximately 66% protein [71]. The solubility of proteins and their amino acid profiles also influence these properties, with house cricket protein being limited in tryptophan and yellow mealworm protein in lysine. Additionally, the lipid composition of insect powders varies, affecting their ability to retain oil. House cricket powder has a higher lipid content (16.1%) than yellow mealworm powder (13.7%) [71], which generally enhances OHC by increasing the capacity to bind and retain oil. Furthermore, chitin, a key structural component in insects, impacts WHC and OHC. Fractions rich in chitin tend to have lower emulsification capacity than protein fractions, suggesting that chitin may reduce the powder's ability to retain water and oil [72]. However, specific structural properties of chitin, such as its degree of deacetylation, can also influence these functional characteristics [71].