M. Elvira López-Caballero

Edible Films and Coatings: Fundamentals and Applications

Edible films and coatings : fundamentals and applications , Edible films and coatings : fundamentals and applications , کتابخانه مرکزی دانشگاه علوم پزشکی تهران

Bioaccessibility and antimicrobial properties of a shrimp demineralization extract blended with chitosan as wrapping material in ready-to-eat raw salmon

A shrimp extract (SME) obtained from the mild-acid demineralization treatment of shrimp shells to produce chitosan was collected. It was mainly composed of fat (≈73%), protein (≈19%), and ash (≈9%) and contained considerable amounts of calcium (≈1.9 g/100 g), astaxanthin (≈30 mg/100 g) and unsaturated fatty acids (≈27% MUFA, ≈39% PUFA). The SME was used in combination with chitosan for wrapping raw salmon to produce a ready-to-eat product enriched in calcium. No significant changes in hardness were found, as compared to the unwrapped salmon. Estimated intakes of bioaccessible calcium increased significantly by 3.6-fold, whereas intake of bioaccessible fat was reduced by 15%. SFA were the main fatty acid group reduced (≈80%), whereas MUFA and PUFA were only reduced by ≈20% each. Total viable counts, pseudomonads, enterobacteria, and specific fish spoilers were reduced by 2-4 log CFU/g in wrapped sample during the chilled storage period (19 days).

Anti-Inflammatory, Antioxidant, and Antimicrobial Effects of Underutilized Fish Protein Hydrolysate

ABSTRACT Antimicrobial, anti-inflammatory, and antioxidant activities of protein hydrolysates from Argentine croaker (Umbrina canosai) protein isolate (CPI) or Argentine croaker myofibrillar protein with different degrees of hydrolysis (DH: 10–20%) prepared using Alcalase or Protamex were determined. Results showed that an increase in the DH resulted in higher content of hydrophobic and aromatic amino acids (AAAs) and in a decrease in molecular weight (MW) distribution for all hydrolysates obtained. Furthermore, the enzyme and raw material used influenced the amino acid content and MW determined. Hydrolysates from CPI with a 20% DH by Alcalase had higher 2,2ʹ-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging activity, metal chelation, and ferric-reducing antioxidant power (p < 0.05). All hydrolysate samples decreased the pro-inflammatory capacity. In all the evaluated microorganisms, only seven were inhibited, most being Gram-positive. Alcalase was found to exert a considerable influence on antibacterial activity. These hydrolysates are an alternative as natural antimicrobials, anti-inflammatory, and antioxidant compounds.