Lactic acid is a versatile chemical with a wide range of industrial applications, including food additives as well as the production of biodegradable plastics, pharmaceuticals and cosmetics. LA can be produced through carbohydrate fermentation using various microorganisms, including lactic acid bacteria (LAB). However, the high production cost of commercial fermentation media for lactic acid raises concerns among researchers. Consequently, there is a demand for research to develop new, more affordable, and sustainable fermentation media. Utilizing underutilized agro-industrial wastes from Malaysia, particularly in the coconut, oil palm, rice, and sugarcane processing industries, offers several advantages. These include biomass reuse, cost-effective production of valuable chemicals, and agricultural waste reduction. This review discusses the potential of underutilized Malaysian agro-industrial waste from the coconut, oil palm, rice and sugarcane processing industries as sustainable carbon sources for LA production. The topics covered encompass the chemical and nutritional composition of the wastes, their potential for lactic acid fermentation with specific microorganisms, factors influencing lactic acid production, and potential applications. Additionally, this review also highlights the challenges and opportunities associated with reutilizing agricultural waste for lactic acid production.

Electrolyzed water (EW) shows great potential as a green and economical sanitation solution for the food industry. However, only limited studies have investigated the optimum electrolysis parameters and the bactericidal effect of acidic electrolyzed water (AcEW) and alkaline electrolyzed water (AlEW). Here, the Box–Behnken experimental design was used to identify the optimum parameters. The tests were conducted with different types of electrodes, electrical voltages, electrolysis times, and NaCl concentrations. There were no obvious differences observed in the physico-chemical properties of EW when different electrodes were used. However, stainless steel was chosen as it meets most of the selection criteria. The best-optimized conditions for AcEW were at 11.39 V, 0.65 wt.% NaCl, and 7.23 min, while the best-optimized conditions for AlEW were at 10.32 V, 0.6 wt.% NaCl, and 7.49 min. The performance of the optimum EW (AcEW and AlEW) compared with commercial cleaning detergents for the food industry was then evaluated. The bactericidal activity of AcEW and AlEW was examined against Escherichia coli ATCC 10536 at different temperatures (30 °C and 50 °C) for 30 s. The results show that both AcEW and AlEW have the ability to reduce the Escherichia coli to non-detectable levels (less than 2 log CFU/mL).