New study analyzes microbial quality of plant-based meat alternatives

A recent study published in the Journal of Consumer Protection and Food Safety investigated the microbial quality of 10 commercially available plant-based ground 'meat' products in northern Germany. The researchers assessed the bacterial presence in these products, made from various plant proteins such as soy, pea, oat, and wheat, at the end of their shelf life.

While the study found no traces of the harmful bacteria Listeria monocytogenes, other Listeria species were present. This highlights the importance of proper refrigeration for these products, as plant-based alternatives, despite generally having lower initial bacterial loads than traditional meat, are not sterile and require proper storage to prevent microbial growth.

The study also points out potential challenges in ensuring complete microbial safety in these products. The high protein content, water activity, and slightly acidic pH of plant-based meat analogs make them susceptible to spoilage by various microorganisms under certain storage conditions.

Although the production process involves a heating step like extrusion, the study identified low levels of bacteria like Enterobacteriaceae, Enterococci, presumptive Bacillus cereus, Listeria spp., and Staphylococcus aureus.

Spore-forming bacteria, such as Bacillus cereus and Clostridium perfringens, pose a particular concern. These bacteria, present in the raw materials, might survive the heating process and germinate later in the product, contributing to the total bacterial count. The study suggests further investigation to assess the potential risks associated with spore-forming bacteria surviving food processing.

The study also emphasizes the importance of proper hygiene during processing, as the detected Listeria and Staphylococcus aureus likely stem from recontamination after the heating step. This is especially crucial as consumers cannot easily judge the cooking adequacy of these products due to the absence of a color change, unlike traditional meat.

The findings of this study highlight the need for further research on ensuring the safety of plant-based meat alternatives, particularly regarding the potential risks associated with spore-forming bacteria and maintaining hygiene throughout the production process.