Antimicrobial activity of tofu whey and steam blanching pea water for enhancement of shelf-life of 3D printed mashed potatoes

Abstract

Using naturally-occurring antimicrobials against the resistance of foodborne pathogens towards antibiotics and chemicals, as well as their insensitivity is a promising research field. Water extracts of legumes have been proven to inhibit microbial development due to the presence of phenolic compounds, protein-derived peptides, saponins and defensin. This study examined the antimicrobial effects of two types of legume water, such as tofu whey (TW) and steam blanching pea water (SBPW), by adding into three-dimensional (3D) printed mashed potato. Composition, moulding, microbial growth assessment and the inhibition zone analysis were conducted. TW and SBPW contained 4 g/100 ml of solid matter, consisting of protein, soluble carbohydrates, minerals and saponins. Results have shown decreased microbial spoilage and enhanced Lactobacillus growth of mashed potato formulated with legume water. Limited inhibition zone (1 mm) was present on TW saponin extract against Staphylococcus aureus and Lactobacillus spp. TW and SBPW addition to 3D printed mashed potatoes encouraged the development of probiotic bacteria, which can be applied to extend shelf-life of food products as well as to develop fermented foods.