Optimisation of Ultra-High Temperature Processing Parameters for Extended Shelf Life Palm Wine in Lagos State

Palm wine is one of Nigeria's most significant traditional beverages, produced from the sap of oil palm and raphia palm trees, but its extremely short shelf life of less than 24 hours under ambient conditions severely limits its commercial distribution potential. Ultra-high temperature processing offers a pathway to extending the shelf life of palm wine while preserving key sensory characteristics. This study optimises ultra-high temperature processing parameters for palm wine collected from tapping sites in Badagry, Lagos State, South West Nigeria, targeting an extended shelf life product that retains acceptable sensory quality. Process variables investigated include treatment temperature (130 to 150 degrees Celsius), holding time (2 to 10 seconds), and pre-treatment carbon dioxide infusion pressure (0.5 to 1.5 bar). Response variables include microbial inactivation, alcohol retention, total sugar content, total phenolic content, antioxidant activity, colour, aroma profile by gas chromatography-mass spectrometry, and overall sensory acceptability. The lethal rate F-value was calculated for targeted microbial load reduction. Results showed that treatment at 135 degrees Celsius for 4 seconds achieved a 5-log reduction in viable microorganisms while retaining 91 percent of initial alcohol content and acceptable sensory scores from 35 habitual palm wine consumers. Total phenolic content was reduced by only 11 percent under optimal conditions. The study draws on recent thermal processing optimisation literature for traditional fermented beverages. Findings provide a processing basis for commercialisation of shelf-stable palm wine. Keywords: palm wine, ultra-high temperature processing, shelf life, thermal processing, Lagos State