Physicochemical Characteristics of Sodium Hydroxide (NaOH) Pretreated Chicken Head Gelatin with Variation of Soaking Time

Chicken head, an abundant pultry by-products, serve as a viable alternative source for gelatin extraction due to their high collagen content accounted for 15%, yet the study about it remains limited. This study specifically focused on optimizing the alkaline pre-treatment step, a standard method for Type B gelatin. The study aimed to analyse the effect of increasing 3% sodium hydroxide (NaOH) soaking time (18, 14, 30, and 36 hours) on the physicochemical characteristics of chicken head gelatin. Data analysis utilized One-Way Anova (α = 5%) followed by DMRT. The optimal yield (2.31%) was achieved after 24 hours of soaking. The highest gel strength was reached after 30 hours soaking (77.95 g Bloom). Viscosity increased with longer soaking times, the highest value was 10.05 mPa.s. Melting point and gel point increased as soaking time increased, the highest value (31.85oC) and (18.82oC), respectively, both was observed after 36 hours soaking. The moisture content ranged from 1.97% (lowest, at 18 hours) to 3.6% and all value were well below the maximum limit set by the SNI. However, ash content (13.43%-29.81%) exceeds the 3% minimum limit set by the SNI.