Advancing Sustainable Innovations in Mulberry Vinegar Production: A Critical Review on Non-Thermal Pre-Processing Technologies

Mulberry is renowned for its medicinal properties and bioactive compounds, yet its high moisture content renders it highly perishable and challenging to transport over long distances. This inherent limitation to its shelf life poses sustainability challenges due to potential food waste and the increased carbon footprint associated with transportation. To address this issue sustainably, mulberry vinegar emerges as a biotechnological solution. Utilizing a fermented mixture of crushed mulberries, sugar, and mixed acid, transforms the highly perishable raw material into a more stable product. However, conventional methods of mulberry vinegar production often involve heat-intensive processing, which poses environmental concerns and energy inefficiencies. Recognizing the need for sustainable practices, this review delves into alternative non-thermal technologies (NTTs) that can revolutionize mulberry vinegar production. These technologies, such as ultrasonication, ultra-high-pressure homogenization, pulsed light treatments, enzyme-assisted pretreatment, and membrane filtration, offer eco-friendly alternatives by eliminating the need for excessive heat. NTTs enhance energy efficiency and sustainability in mulberry vinegar production by deactivating the microbes and extending the shelf life, thereby enhancing product stability and quality without using thermal methods. Ultrasonication, for example, plays a pivotal role in improving bioactive compound extraction, contributing to the overall quality enhancement of mulberry juice. Enzyme-assisted pretreatment, specifically with Pectinex Ultra SP-L and Viscozyme L, not only enhances juice quality, but also holds promise for sustainable vinegar production. Furthermore, ultra-high-pressure homogenization and pulsed light treatments positively influence mulberry processing, offering additional sustainable alternatives. Membrane filtration, especially ultrafiltration, not only enhances the phenolic content, but also contributes to stability in mulberry juice, showcasing potential benefits for vinegar production. In conclusion, exploring these NTTs represents a transformative shift from traditional heat treatment methods in mulberry food processing. By providing energy efficient, environmentally friendly, and high-quality alternatives, this review offers valuable insights into sustainable practices, particularly in mulberry vinegar production, thereby contributing to a more sustainable future for the mulberry food industry.