Rheological and functional characterization of gelatin and fat extracted from chicken skin for application in food technology

Abstract

Chicken skin is a major byproduct of the poultry industry. This study was undertaken to extract and characterize fat and gelatin from chicken skin. To do this, the chicken skin was wet‐rendered at different temperature–time combinations and the yield and properties of the extracted gelatin and fat were determined. Gelatin and fat were recovered at yield ranges of 0.74%–2.03% and 24.01%–27.91%, respectively. The time and the interaction of time–temperature had a positive effect on gelatin yield (p < .05); however, the fat yield was not affected by the extraction condition. Protein, ash, and hydroxyproline content of gelatin and unsaponifiables and free fatty acids contents, peroxide value, and induction period of oxidation of the fat were affected by the extraction condition. Functional and rheological analyses showed chicken skin gelatin gel/solution had a higher bloom value, viscosity, foaming capacity, storage and loss moduli, and melting and gelling points than the commercial bovine gelatin. Oleic (42.13%), palmitic (24.6%), and linoleic (17.53%) acids were the main fatty acids of chicken skin fat. The storage modulus of chicken skin fat was higher than the loss modulus up to 31°C; however, because of a low slip melting point (22.74°C) and solid fat content, it was fluid at room temperature. The findings of this research can be useful in the development of processes for the extraction and application of chicken skin gelatin and fat.

Textural, rheological, and structural properties of turkey and chicken gelatins from mechanical deboning residues

“…Chicken gelatin possesses favorable sensory properties because gelatin that melts at higher temperatures provides better mouthfeel (Sinthusamran et al., 2014 ). The amounts of proline and hydroxyproline, differences in molecular weight, and the relative content of α‐ and β‐chain components influence the thermal behavior of gelatins significantly (Abuibaid et al., 2020 ; Mohammadnezhad & Farmani, 2022 ). As the ratio of these amino acids increases, the melting and gelling temperatures also increase.…”

Enzyme‐assisted extraction of chicken skin protein hydrolysates and fat: Degree of hydrolysis affects the physicochemical and functional properties

“…This balanced fatty acid composition makes chicken fat ideal for use in food processing technology, especially in the formulation of soft‐tub margarine and Vanaspati (Naderi et al, 2016). Gelatin obtained from chicken skin has shown to have a higher bloom value than the bovine gelatin and can be extracted from chicken skin at a rate of 16%‐ dry basis (Mohammadnezhad & Farmani, 2022; Sarbon et al, 2013). Moreover, chicken skin gelatin has a higher viscosity and fat binding capacity, and better foaming properties than mammalian gelatins (Mohammadnezhad & Farmani, 2022; Mrázek et al, 2019).…”

“…Gelatin obtained from chicken skin has shown to have a higher bloom value than the bovine gelatin and can be extracted from chicken skin at a rate of 16%‐ dry basis (Mohammadnezhad & Farmani, 2022; Sarbon et al, 2013). Moreover, chicken skin gelatin has a higher viscosity and fat binding capacity, and better foaming properties than mammalian gelatins (Mohammadnezhad & Farmani, 2022; Mrázek et al, 2019). Protein hydrolysates obtained from chicken skin proteins play several functions in food and biological systems.…”