The brief video shows and explains the chemistry behind the browning of lemon juice upon heating, thereby revealing a secret message.

 

Sources

Vitamin C – wie ein Apfel nicht (so schnell) braun wird, Agnes-Pockels-SchülerInnen-Labor, TU Braunschweig, Germany, 2017. (accessed November 18, 2023)

Sonali S. Bharate, Sandip B. Bharate, Non-enzymatic browning in citrus juice: chemical markers, their detection and ways to improve product quality, J. Food Sci. Technol. 2014, 51(10),  2271–2288. https://doi.org/10.1007/s13197-012-0718-8

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