The effect of a nano-biosensor based on ZnO nanoparticles and peroxidase enzyme on microbial, chemical and sensory characteristics in red meat during storage at ۴ °C

The escalating demand for fresh, safe, and minimally processed meat products has driven innovations in food packaging technologies, particularly in the realm of smart and active systems capable of real-time quality monitoring and preservation. This study was designed to evaluate the efficacy of a novel nano-biosensor composed of zinc oxide (ZnO) nanoparticles immobilized with peroxidase enzyme on polyethylene films for application in minced red meat packaging under refrigerated conditions. The biosensor was engineered to serve dual purposes: inhibiting microbial proliferation through the inherent antimicrobial properties of ZnO and providing visible colorimetric indicators of spoilage progression via enzymatic reactions to volatile amines and oxidative byproducts. Fresh bovine minced meat samples were divided into control (conventional polyethylene packaging) and treatment (polyethylene integrated with the nano-biosensor) groups, vacuum-packaged, and stored at ۴±۰.۵ °C for ۱۰ days. Comprehensive analyses were conducted at ۰, ۳, ۵, ۷, and ۱۰ days to assess microbial, physicochemical, and sensory quality parameters. Total viable count (TVC), psychrotrophic bacterial count, Enterobacteriaceae, lactic acid bacteria, pH, thiobarbituric acid reactive substances (TBARS) as malondialdehyde (MDA) equivalents, color stability (L*, a*, b*), drip loss, and sensory attributes (color, odor, texture, overall acceptability) were monitored. The nano-biosensor exhibited progressive color shifts from pale yellow to deep orange-red correlating with spoilage thresholds, enabling consumer-readable freshness indication without instrumentation. Microbiologically, the treatment group maintained TVC below ۷ log CFU/g throughout storage, compared to the control exceeding this limit by day ۷. Psychrotrophic and Enterobacteriaceae counts were suppressed by ۱.۵-۲.۰ log cycles in biosensor-packaged samples. Lipid oxidation was markedly reduced, with MDA levels ۳۸-۴۵% lower in the treatment group by day ۱۰. The pH rise was decelerated, remaining below ۶.۰ versus ۶.۴ in controls. Instrumental color analysis revealed superior retention of redness (a* value) and reduced metmyoglobin formation in treated samples. Sensory panel scores indicated significantly higher acceptability for odor and overall quality in the biosensor group, with no off-flavor development until day ۱۰. The biosensor's antimicrobial mechanism is attributed to ZnO-induced reactive oxygen species generation and membrane disruption, while peroxidase facilitated sensitive detection of biogenic amines. These integrated effects extended the marketable shelf life from ۵-۶ days (control) to ۹-۱۰ days (treatment). The technology aligns with clean-label trends, requiring no synthetic preservatives, and offers scalability for industrial adoption. This research establishes the ZnO-peroxidase nano-biosensor as a multifunctional platform for enhancing meat safety, reducing food waste, and empowering consumers with intuitive quality cues, thereby bridging environmental health concerns in meat processing with advanced food preservation strategies.

کلیدواژه ها:

Nano-biosensor ، Zinc oxide nanoparticles ، Peroxidase enzyme ، Minced red meat ، Smart packaging ، Microbial control ، Lipid oxidation ، Colorimetric indicator ، Refrigerated storage ، Shelf life extension ، Food safety ، Sensory quality