Effect of organic acid on recovery yields and characteristics of rohu (Labeo rohita) protein isolates extracted using pH shift processing

Abstract

BACKGROUND Proteins recovery using hydrochloric acid (HCl) in acid‐aided solubilization could cause greater loss in its functionality over alkali‐aided solubilization. Moreover, using HCl in edible foods is also a health concern. Replacing HCl with organic acids for acid‐aided solubilization could address these problems. The aim was to study the effect of organic acid (glacial acetic acid) as a replacement for HCl during pH shift processing on the characteristics and functionality of rohu (Labeo rohita) protein isolates. Rohu proteins were obtained by solubilizing at pH 3.0 and pH 11.0 using glacial acetic acid and sodium hydroxide (10 mol L−1). RESULTS Results showed that solubilization at pH 11.0 gave higher protein yields (766.8 ± 2.4 g kg−1) compared to solubilization at pH 3.0 (735.7 ± 7.1 g kg−1) (P < 0.05). Isolates from acid‐aided solubilization had higher whiteness and total pigment content over isolates obtained by alkali‐aided solubilization. Rohu isolates recovered by alkaline solubilization showed higher water and oil holding capacity, gel strength, folding scores, foaming and emulsion capacity than acid processed isolates (P < 0.05). Solubilization of rohu proteins using glacial acetic acid produced isolates with low breaking force (149.0 g), low storage modulus (G′) values and low folding test score (1.0) over the alkaline isolates (P < 0.05). CONCLUSION Results indicated that, recovering rohu proteins using organic acid (glacial acetic acid) could produce isolates with poor functional properties, while using the organic acid to precipitate the proteins solubilized by alkali‐aided processing could produce proteins with better yields and functionality. © 2019 Society of Chemical Industry

Utilization of pangas protein isolates and by‐products in fish sausages: Effect on quality attributes and acceptability

“…Several studies reported the application of acid-and alkali-based extraction process for extracting proteins from fish, fish waste, and by-products (Baraiya et al, 2020;Nolsφe et al, 2007;Surasani, Tyagi, et al, 2017;Surasani, 2018, Surasani, Mandal, et al, 2018Surasani, Raju, et al, 2019;Surasani, Raju, Shafiq, & Baraiya, 2020).…”

“…Several studies reported the application of acid‐ and alkali‐based extraction process for extracting proteins from fish, fish waste, and by‐products (Baraiya et al, 2020; Nolsφe et al, 2007; Surasani, Tyagi, et al, 2017; Surasani, 2018, Surasani, Mandal, et al, 2018; Surasani, Raju, et al, 2019; Surasani, Raju, Shafiq, & Baraiya, 2020). Only a few reports are available on utilization of recovered proteins and by‐products from fish processing waste for human edible purpose (Shaviklo, 2008; Singh et al, 2021; Surasani, 2017; Surasani et al, 2022; Surasani, Raju, Shafiq, Chandra, & Lakshmisha, 2020; Surasani, Raju, & Singh, 2021; Surasani, Raju, Singh, & Joshi, 2021; Surasani, Singh, et al, 2019), which necessitates the further research in this area.…”