Effects of ozone treatment to milk and whey concentrates on degradation of antibiotics and aflatoxin and physicochemical and microbiological characteristics

Effects of gaseous ozone treatment on the mite pest control and qualitative properties during ripening storage of pecorino cheese

BACKGROUND

Ripened cheeses, such as pecorino, are susceptible to mites and molds contamination on the crust area that must be removed before the product can be marketed. This study investigates the effectiveness of gaseous ozone treatment in the control of microbiological and mite growth without negatively affecting product quality.

RESULTS

Cheese samples were treated with gaseous ozone at 200 and 300 ppb for 8 h per day (overnight) for 150 days in storage rooms under controlled conditions (12 °C and 85% relative humidity). The results showed that ozone at 200 ppb limits the growth of mites starting from 25 days of storage and significantly reduced bacteria, molds, and yeasts counts starting from 75 days of storage. Concerning the physicochemical and qualitative parameters evaluated during ripening (weight loss, moisture content, dry weight, ash, fat, protein, total nitrogen, color, non-destructive firmness), no significant differences were shown between the control samples and ozone treatment at 200 ppb. Sensory analysis (consumer test) also showed no specific defects with the ozone-treated samples. It was observed that the ozone treatment at 300 ppb had limited microbiological growth and no alteration of sensory aspects but did not have the same positive impact on some aspects of overall quality, compared with ozone treatment at 200 ppb.

CONCLUSION

The use of gaseous ozone treatments during ripening of pecorino cheese can potentially offer an excellent solution for the control of mite growth, while preserving the quality and sensory characteristics of the product. For this reason, this technique could be very useful for commercial purposes. © 2022 Society of Chemical Industry.

The Use of Ozone Technology: An Eco-Friendly Method for the Sanitization of the Dairy Supply Chain

The dairy field has considerable economic relevance in the agri-food system, but also has the need to develop new 'green' supply chain actions to ensure that sustainable products are in line with consumer requirements. In recent years, the dairy farming industry has generally improved in terms of equipment and product performance, but innovation must be linked to traditional product specifications. During cheese ripening, the storage areas and the direct contact of the cheese with the wood must be carefully managed because the proliferation of contaminating microorganisms, parasites, and insects increases significantly and product quality quickly declines, notably from a sensory level. The use of ozone (as gas or as ozonated water) can be effective for sanitizing air, water, and surfaces in contact with food, and its use can also be extended to the treatment of waste and process water. Ozone is easily generated and is eco-sustainable as it tends to disappear in a short time, leaving no residues of ozone. However, its oxidation potential can lead to the peroxidation of cheese polyunsaturated fatty acids. In this review we intend to investigate the use of ozone in the dairy sector, selecting the studies that have been most relevant over the last years.

Removal of antibiotics from milk via ozonation in a vortex reactor

Antibiotics (ABX) residues occur frequently in milk, causing considerable wastage of medicated milk and serious economic losses, and making the issue a burden for the dairy industry. Improper disposal of medicated milk harms dairy production, animal welfare, and the environment. This work studies the use of ozonation in a vortex reactor for removing ceftiofur hydrochloride (CEF), sulfamonomethoxine sodium (SMM), marbofloxacin (MAR) and oxytetracycline (OTC) from milk. In terms of residual concentration, O₃ efficiency and the degradation kinetics of the various O₃-involving processes in the vortex reactor, ABX removal via ozonation is better using stronger vortexing, which induces hydrodynamic cavitation. CEF undergoes the fastest degradation, followed by SMM, MAR, and OTC. High ABX hydrophobicity favors ABX degradation via ozonation, O₃/H₂O₂, and O₃/Na₂S₂O₈. ABX oxidation by ^•OH at the O₃ gas-bubble/milk interface is the principle degradation pathway, except for MAR. ABX degradation follows pseudo-first-order kinetics and is affected by initial ABX concentration, O₃ concentration/flow rate, reaction temperature, and milk components to varying degrees. Under optimal ozonation conditions, ABX residues meet the maximum limits as set by the European Commission and no antimicrobial activity was observed. The decontaminated milk was therefore suggested to be reused as calf food, animal feed, organic fertilizer, etc.