AbstractUnderstanding the temperature profile of different packaging materials would be useful for selecting appropriate packaging material for in‐bottle pasteurization. The temperature profile of polypropylene, polyethylene (PE), and polyethylene terephthalate bottles was investigated using COMSOL Multiphysics software to understand the temperature–time correlation with thermal treatments. PE bottles exhibited the least temperature difference between cold and hot spots. Optimization of thermal treatment processing parameters such as temperature (80–95°C) and treatment time (5–15 min) for inactivation of enzymes, namely polyphenol oxidase (PPO) and peroxidase (POD), in tender coconut water (TCW) was performed to the extent its shelf life. The quality parameters of heat‐treated TCW such as pH, total soluble solids (TSS), titratable acidity (TA), turbidity, phenolic content, PPO, POD, and sensory evaluation were analyzed. The multiple linear regression models were developed for each quality parameter using a central composite design (CCD). The optimized treatment conditions were 84°C temperature and 5 min treatment time with the desirability of 0.926. The responses recorded were pH = 5.4, TSS = 5.52, turbidity = 7.1 NTU, TA = 0.06% of malic acid, relative PPO = 0.099, relative POD = 0.093, phenolic content = 44.712 mg gallic acid equivalent/L, and overall acceptability score = 8.Practical ApplicationsUnderstanding the temperature profile of different packaging materials during pasteurization or sterilization is imperative to select the suitable packaging material, and also it would be helpful for designing the heating system. Tender coconut water (TCW) is the most popular natural drink in Asian countries. However, the pasteurization conditions are yet to be optimized to preserve TCW without affecting its bioactive and functional components. The current practice followed for in‐bottle sterilization of TCW is polyethylene terephthalate (PET). This is due to PET being cheaper and readily available than other packaging materials. However, the quality of the TCW could affect PET due to improper heat distribution which can lead to damage of bioactive components. The present study has optimized the suitable pasteurization conditions and packaging material for bottling and marketing TCW. The findings of the present study will boost the market potential of the tender coconut processing industries.