Enhanced strawberry preservation using H. pluvialis residue-based films

• Published in: Food and bioproducts processing Vol. 153; pp. 418 - 429
• Main Authors: Yao, Liuchun, Chen, Zhipeng, Huang, Liangliang, Xian, Feng, Gao, Jing
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2025
• Subjects: Chitosan; Food packaging; Haematococcus pluvialis; Residue; Strawberry preservation; Food packaging; Chitosan; Films; Residue; Haematococcus pluvialis; Strawberry preservation
• ISSN: 0960-3085
• DOI: 10.1016/j.fbp.2025.07.013

Novel films composed of Haematococcus pluvialis residue (HPR), chitosan (CS), citric acid (CA), glycerol (GL), and calcium chloride (CaCl₂) were developed to improve strawberry preservation. The rheological, structural, and functional properties of film-forming aqueous solutions (CS/CA, CS/CA/GL, CS/CA/GL/Ca, CS/CA/GL/Ca/HPR) were analyzed. It revealed HPR-induced shear-thinning behavior (η = 2260 Pa·s) and enhanced rigidity (G'' = 750.51 Pa at 100 rad/s) via hydrogen bonding and Ca²⁺ crosslinking. FTIR and UV–vis spectra confirmed molecular interactions between carboxyl groups of HPR and amino residues of CS. The films with 0.6 % HPR exhibited superior mechanical strength (tensile strength: 12.16 MPa; elongation at break: 135.36 %), reduced water vapor permeability (1.14 × 10−10gm⁻¹s⁻¹Pa⁻¹), and antioxidant activity (73.16 % DPPH scavenging) than CS film. Antibacterial efficacy against S. aureus and E. coli peaked at 0.8 % HPR. The weight loss of strawberry was reduced by using the HPR film (13.08 % vs. control: 29.5 %), retained ascorbic acid (19.98 mg/100 g vs. control: 6.75 mg/100 g). The shelf life of strawberries was extended by 30 days, which is 15 days longer than that of those wrapped with polyethylene film. The polysaccharides, astaxanthin, and algal proteins in HPR improved barrier properties, oxidative stability, and microbial resistance. These results highlight the potential of HPR films as sustainable, multifunctional packaging to extend fruit shelf life. [Display omitted] •H. pluvialis residue (HPR)-based films were prepared.•Mechanical strength, antioxidant activity, and antibacterial efficiency of the film were higher than chitosan film.•The HPR films extended the shelf-life of the strawberry to 30 days at 4 ℃.•The biofilms presented an innovative alternative for active food packaging.