Commercially available kerupuk (Indonesian traditional crackers) are typically high in fat and low in protein, making them nutritionally imbalanced and categorized as junk food. This study aims to develop a protein-source and fat free traditional crackers through egg white powder (EWP) substitution and application of alternative frying methods. The substitution of EWP in was selected at a 20% level based on preliminary test ranging from 0% to 40% and the alternative frying methods were deep frying (control), air frying, sand frying, and microwaving. The developed traditional crackers was characterized with pH value between 7.20 and 7.34; water activity (a w) between 0.41 and 0.42; protein and fat levels respectively ranging from 18.26% to 18.73% and 0.19%-0.41%, meeting the claims as a protein source and fat free product according to Indonesian Food and Drug Authority (BPOM). SEM analysis showed that microwave cooking and deep-frying produced traditional crackers with highly porous structures with large pores. FTIR analysis indicated that deep-fried traditional crackers showed intense peaks at 2930-2850 cm-1 (C-H stretching) and 1743 cm-1 (C = O ester carbonyl stretching), indicating high oil absorption, whereas alternative frying methods showed lower intensities of these lipid-associated peaks. Traditional crackers produced had a pH value ranging from 7.20 to 7.34 and water activity (a w) between 0.41 and 0.42. Microwave emerged as the optimal alternative frying technique, with the highest expansion rate (185.63%), crispness (37.58 mm), and brightness (L* = 92.88).
Wardana et al. (Sun,) studied this question.