Fig. 3 shows the results of yield opti-mization in terms of VS destroyed. The maximum yield observed was 0.6 g lactate produced per gram VS destroyed at 150 g VS L−1.The yield consistently decreased as loading rate increased there-after. Previous experiments with a pure culture of L. plantarum, anorganism identified to dominate food waste fermentations, foundan optimum yield at 5% reducing sugars [10,12,20]. Similarly, aloading of 150 g VS L−1was shown to contain 6% reducing sugarsin subsequent batches of this work supporting the optimization ofyield at this loading rate