Valorization of cacao pulp to produce functional drink with electrolyte potential using membrane technology

Abstract

In this study, the production of fresh and fermented cacao water is investigated. The impact of fermentation and membrane-based sterilization on the chemical and physical properties of the cacao water are evaluated. Fresh cacao water contains higher levels of phenolic compounds compared to coconut water, offering superior antioxidant properties despite the lower pH and mineral concentration. The investigation into the fermentation process highlights the role of sucrose as a substrate for microbial metabolism in Saccharomyces cerevisiae , resulting in distinct fermentation dynamics. The observed changes include reduced pH, color shifts due to the Maillard reaction, and an enhancement of phenolic and antioxidant concentrations through the breakdown and formation of bioactive compounds. Microfiltration of the fresh and fermented cocoa water effectively eliminates microorganisms, despite reducing antioxidant and phenolic content due to the membrane retention. Membrane fouling is noted due to the adhesion of polysaccharides, proteins, and polyphenols to membrane surfaces. The sterilized-fermented cacao water exhibits a significantly extended shelf life during storage, which is 7.27 days at 25 °C and 58.84 days at 13 °C. This extended shelf life for the fermented sample is attributed to a lower pH and higher phenolic content, which inhibit microbial growth. Analysis of microbial growth, pH, and total dissolved solids during storage indicates accelerated degradation of the cacao water with increasing storage temperature.