Carboxy Methyl Cellulose, Xanthan Gum, and Carrageenan Coatings Reduced Fat Uptake, Protein Oxidation, and Improved Functionality in Deep-Fried Fish Strips: An Application of the Multiobjective Optimization (MOO) Approach.

In this study, a multiobjective optimization (MOO) approach was utilized for effective decision-making when several variables were changing simultaneously during frying. Carboxy methyl cellulose (CMC), xanthan gum, and carrageenan coatings in different concentrations (0.25-1.50%, w/v) were applied on fish strips to reduce the oil uptake and protein oxidation during frying. The pickup of the strips increased significantly (p < 0.05) with increasing concentration. The CMC was effective in oil uptake reduction and protein oxidation, as revealed by the lower carbonyl and sulfhydryl contents in the fried strip. The hardness and chewiness of the coated fish strips were found to be declined significantly (p < 0.05) with increasing coating concentrations. The moisture, lipid, toughness, hardness, cutting force, oiliness, sulfhydryl content (all min), oil uptake reduction, and carbonyl content (both max) were considered as multiple criteria for the MOO technique, and fried strips coated with 1% CMC, followed by 0.75% xanthan gum and 0.75% carrageenan, emerged as the best optimal coating.

Valorisation of pineapple peel waste as natural surimi gel enhancer and its optimization in Nile tilapia (Oreochromis niloticus) surimi gels.

This investigation explored the preparation of surimi gel enhancer from pineapple peel waste, hugely generated by industries and spreading serious environment pollutions. The peel extracted with 100% ethanol had higher bioactive and antioxidant attributes, which was subsequently fortified in tilapia surimi at levels of 0.20%-1.20%, w/w to improve its physiochemical, textural, protein structural and sensorial properties. Our finding demonstrated that surimi gels enriched with 0.80% ethanolic pineapple peel extract (PAPE) exhibited significant (p<0.05) improvement in water holding capacity, breaking force, gel strength, and other textural properties and sensory attributes. Furthermore, the surimi gels fortified with 0.80% PAPE exhibited the elevated levels of hydrogen and hydrophobic interactions, while sulfhydryl and free amino acid contents demonstrated a contrasting trend. The FTIR spectra displayed that the incorporation of PAPE influenced the secondary structure of the protein, as evidenced by shifts in the α-helix to ß-sheet peaks. In addition, 0.80% PAPE added gels displayed a compact, uniform, and organized microstructure, featuring small cavities. In summary, the fortification of tilapia surimi gels with 0.80% PAPE could improve gelling and other technological properties with higher sensory scores. This study offers an effective approach to utilize the pineapple peel as a gel enhancer additive for the development of functional surimi and surimi-based products enriched with bioactive compounds.

Manipulation of protein structure and bonding pattern to improve the gelling and textural quality of surimi gels from silver carp: incorporation of mosambi (Citrus limetta) peel extract.

BACKGROUND: This investigation focused on the use of mosambi peel extract (MPE) fortification (at 0% to 1.50%, w/w) in silver carp surimi to improve the gelling, textural, and other physicochemical properties of the surimi. RESULTS: The peels were extracted in ethanol (40-100% concentrations, v/v) and water. It was found that 100% ethanol had significantly (P < 0.05) higher yield and total phenolic, flavonoid, and tannin content. The fortification of MPE at optimum level (0.75%) improved the breaking force (55.1%) and gel strength (89.9%) significantly (P < 0.05) in comparison with 0% MPE gel samples. Moreover, 0.75% MPE-fortified gels had higher hydrogen and hydrophobic bonds, higher water-holding capacity, and lower sulfhydryl groups and free amino groups. The myosin heavy chain (MHC) bands in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) disappeared completely in the MPE-fortified gels. Fortification with MPE affected the secondary structures of protein as shifting of peaks was observed in Fourier-transform infrared (FTIR) spectra. Scanning electron microscopy (SEM) images showed relatively organized finer and denser gel networks in MPE-treated gels. CONCLUSION: The surimi gels fortified with 0.75% MPE demonstrated improved gelling properties, with an overall higher acceptability than the unfortified gels (0% MPE). The fortified gels also became enriched with bioactive polyphenols, which are generally not present in surimi. This study provides an efficient way to utilize mosambi peel to develop functional surimi and surimi-based products with improved gel ability. © 2023 Society of Chemical Industry.

Effects of Pineapple Peel Ethanolic Extract on the Physicochemical and Textural Properties of Surimi Prepared from Silver Carp (Hypophthalmichthys molitrix).

The effects of ethanolic pineapple peel extract (PPE) powder at various concentrations (0-1.50%, w/w) on the gelling properties of silver carp surimi were investigated. The pineapple peel extract produced with 0-100% ethanol, revealed that 100% ethanol had the highest bioactive properties. Surimi gels with added PPE powder demonstrated improved gel strength (504.13 ± 11.78 g.cm) and breaking force (511.64 ± 11.80 g) up to 1% PPE addition; however, as PPE concentration increased beyond 1%, the gel strength decreased. Similarly, with the addition of 1% PPE powder, more hydrophobic bonds and fewer sulfhydryl groups and free amino groups were seen. However, the gels with PPE powder added showed a slight reduction in the whiteness of the surimi gels. FTIR analysis indicated that the fortification with PPE powder brought about the secondary structure of myofibrillar proteins; peaks shifted to the ß-sheet region (PPE gels) from the α-helix region (control). SEM analysis indicated that the gel with 1% PPE powder had a relatively organized, finer and denser gel architecture. Overall results suggested that the addition of PPE powder up to 1% to the surimi gels enhanced the gelling properties as well as the microstructure of the surimi.