The identification of 41◦C as maximizing lactate is supported by optimums previously reported. Lactate dehydrogenase, the enzyme that converts intermediate pyruvate to lactate, was found to have more than 37% higher activity at 35◦C than at 20◦C or 50◦C in the co-digestion of food waste with sludge [15]. Further, between 35◦C and 45◦C has been observed to have the highest rate of food waste solubilization during fermentation [4]. Therefore it is reason-able that an optimum temperature would be identified within the range of 35–55◦C tested in this experiment, and that 41◦C would balance the first and last biochemical reactions in the conversion of food waste to lactate.