ABSTRACT
Fish by-products are excellent sources of collagen. Acid-soluble collagen (ASC) derived from a mixed by-product of different fish species was hydrolyzed to obtain peptide fractions and evaluate their biological and functional activities. All fractions obtained (F1: ≥30, F2: 10-30, F3: 5-10, F4: 1-5, and F5: ≤1kDa) exhibited antioxidant activity at concentrations of 5, 10, and 15 mg/mL. However, F5 registered the highest reducing power (absorbance 0.366) and hydroxyl-radical-scavenging activity (91%) at 15 mg/mL; whereas the highest DPPH scavenging activity (81%) was also detected in F5 at 5 mg/mL. The solubility of F1, F2, and F3 was ≥ 95% at pH 7. The highest foaming capacity (78%), foaming stability (60%), and emulsion stability index (42 min) were registered for F1. However, the highest emulsifying activity index (130 m2/g) was for F3. These results place collagen obtained from a mixed by-product of different fish species as a potential biotechnological alternative for the industry.
Subject(s)
Antioxidants/pharmacology , Collagen/chemistry , Fish Products , Fish Proteins/chemistry , Peptides/chemistry , Peptides/pharmacology , Amino Acids/analysis , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Antioxidants/chemistry , Emulsifying Agents/chemistry , Fish Proteins/pharmacology , Free Radical Scavengers/chemistry , Hydrogen-Ion Concentration , Hydrolysis , Hydroxyl Radical/chemistry , Protein Hydrolysates/chemistry , SolubilityABSTRACT
The objective of this study was to evaluate the efficacy of propolis extract (PE) to reduce lipid oxidation and microbial growth on beef patties during refrigerated storage. Beef patties were manufactured by incorporating PE in 4 different treatments: (1) Control (no PE addition); (2) commercial propolis 1 (2% w/w; CP1); (3) commercial propolis 2 (2% w/w; CP2); and (4) noncommercial propolis (2% w/w; NCP). Raw patties were wrapped with polyvinyl chloride and stored at 2 °C for 8 d. Total phenolic content (TPC), free-radical scavenging activity (FRS), and polyphenolic content of the PE were evaluated using high-performance liquid chromatography (HPLC). Lipid oxidation (thiobarbituric acid-reactive substances (TBARS), conjugated dienes (CnDs), metmyoglobin (MetMb%), pH variation, and color (L*, a*, b*, C*, and h*), and microbial growth (mesophilic and psychrotrophic bacteria) of patty samples were measured. NCP treatment demonstrated the highest FRS (64.8% at 100 µg/mL), which correlated with TPC and the presence of polyphenolic compounds. Lipid oxidation (78.54%, TBARS; 45.53%, CnD; 58.57%, MetMb) and microbial mesophilic and psychrotrophic growth (19.75 and 27.03%, respectively) values were reduced by NCP treatment in refrigerated samples after 8 d. These results indicate that PE has great potential as a natural antioxidant and antimicrobial additive to extend the shelf life of beef patties.
