Exploring gelatin from Black Bengal and Native Deccani Goat skin: Specialty meat breeds of India

Abstract

The study was conducted to characterize gelatin extracted from the skins of Black Bengal Goat (BBG) and Native Deccani Goat (NDG) under hot-air and freeze-drying conditions. The findings revealed higher (p < 0.05) gelatin yield, gel clarity, hydroxyproline content, lightness scores, and instrumental texture properties especially hardness for BBG samples. Freeze-drying yielded superior (p < 0.05) gel strength (453.72 ± 0.49 g vs. 437.56 ± 0.06 g) and viscosity (30.70 ± 0.28 cP vs. 15.73 ± 0.35 cP) relative to hot-air dried samples. Scanning electron microstructure of gelatin gels revealed greater intertwinement of protein strands with compact, corrugated sheet-like appearance without any voids in BBG samples. The FTIR analysis exhibited Amide I peaks for all the samples at 1623–1625.5 cm⁻¹ frequency indicating greater stability of triple helical structure of gelatin, whereas Amide II peaks were observed at 1540.22 cm⁻¹ for freeze dried samples which denotes the significant presence of α-helical structures. The MALDI-TOF MS analysis of SDS-PAGE protein bands revealed the presence of collagen type I-α1 as a predominant chain in both NDG and BBG, however few specific peptides originating from collagen type XXII-α1 and Collagen α-1(III) chain were exclusively observed in BBG only. A species-specific peptide R.GETGPAGPAGPIGPVGAR.G (m/z, 1560.83) with a potential to authenticate goat skin gelatin was deciphered in both NDG and BBG. Current study has demonstrated the superior quality and functionalities of Black Bengal goat skin gelatin and may serve as a potential alternative to commercially available beef and pork skin gelatin.