3. Lactic Acid Bacteria

Because whey contains naturally high counts of LAB (in this case 10<sup>7</sup> cfu·g<sup>−</sup>1), which could induce a higher bacterial load into the product, we investigated the evolution of LAB counts in all treatments throughout cold storage time, and results are presented in Figure 7c. As can be seen, although on day 1 there was a significant difference between LAB counts in all treatments, from day 3 onward, the presence of live LAB from fermented whey did not confer a significant difference (*p* > 0.05) when compared to chlorine and water treatments. This type of bacteria is normally present in MP vegetables in loads from 2 to 6 log cfu·g−<sup>1</sup> (Figure 7c; at day 0, our reference sample was around 3.5 log cfu·g<sup>−</sup>1), so LAB counts ended up being similar in all treatments tested, meaning that the introduction of LAB from whey would not pose any noticeable difference to the final product. Furthermore, it has been shown that the presence of these LAB could have a positive antimicrobial effect in lettuce and apple

taste [35]. Additionally, the presence of lactic acid, antibacterial peptides, and low pH are contributive factors for the inhibitory effects of whey [53–55].
