Emerging Technologies for Processing and Preservation of Coconut Inflorescence Sap

Coconut inflorescence sap or neera is an abundant source of nutrient-rich compounds and a highly perishable drink. Owing to the inclusion of native microbiota, it is very prone to fermentation. Neera harvesting is reportedly more economical for farmers as it generates a high income compared to harvesting coconuts alone. The density of nutrients and the time involved in the neera extraction process make the sap vulnerable to natural fermentation in the presence of an active bacterial population. For this reason, the pooling of unfermented hygienic sap is tricky. The processing and preservation of neera is done mainly by inactivating the microbes and retarding the fermentation process. Neera ferments in 2–3 h when stored at room temperature and in 3 days of refrigerated storage. Traditionally, neera was processed using physical, chemical, biological, and thermal methods to prolong its shelf life. The existing neera preservation techniques, such as pasteurization, centrifugation and deodorization, ultrafiltration, and the addition of chemical additives, have certain potential disadvantages, including unfavorable quality changes. In this regard, nonthermal techniques such as ozone processing, pascalization (HPP—High Pressure Processing), pulsed electric field (PEF), light treatment (UV treatment and pulsed light), and cold plasma (CP), are emerging as an alternative for the neera preservation. The application of nonthermal techniques and chemical preservatives in the arrest of neera microbial contamination may contribute to improved accessibility for consumers and economic possibilities. This chapter emphasizes the emerging techniques involved in neera processing and discusses the issues encountered in prolonging its shelf life.