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How Does Coffee Become Decaf?
Coffee stands apart from many foods by having a higher concentration of caffeine molecules within its cells than most food items, meaning even small doses have an impactful impact on our ability to remain alert or feel energetic. There are various methods available for extracting caffeine from coffee beans to create decaf coffee such as chemical solvents such as methylene chloride or ethyl acetate; Swiss Water Process; or supercritical carbon dioxide extraction.
Solvent-based methods involve immersing coffee beans directly in a chemical solvent like methylene chloride, ethyl or isopropyl acetate, then passing their caffeine-rich extract stream over activated carbon that displays high selectivity for caffeine – this allows coffee solubles to be separated from caffeine for reuse in future decaffeination cycles; finally, the remaining caffeine-free solution is added back to the beans to continue processing and the cycle continues.
Though the direct method is certainly efficient in producing great coffee, health concerns over its use of toxic chemicals prompted search for better decaffeination alternatives. An ideal method would remove caffeine without negatively affecting other elements of coffee such as oils and flavor compounds or leaving any residual solvent taste behind; this presents quite a challenge as caffeine molecules reside deep within bean cells.
Initial efforts at decaffeinating with organic solvents proved unsuccessful due to unwanted side effects and changes in coffee bean characteristics, prompting research for alternative techniques – with chemists playing an essential part in keeping these processes running efficiently as well as developing new ones.
Today, decaf coffee is typically produced using one of two processes – chemical solvent or Swiss Water Process. Chemical solvent is most often methylene chloride which is both synthetically manufactured and extracted from fruit ripening processes; this volatile compound evaporates readily when exposed to roasting temperatures, leaving only trace amounts behind in final cup of decaf coffee.
Organic solvents used for decaffeination work by dissolving and separating caffeine from coffee beans into its component parts; leaving only recyclable or discardable solubles behind for recycling/disposal. Following decaffeination, coffee beans must then be rinsed to eliminate methylene chloride and dry properly before being stored away for storage or sale.
The Swiss Water process offers an alternative to organic solvents and works similarly. First, green coffee beans or tea leaves soaked in water are put into a vessel filled with supercritical CO2. It acts as both gas and liquid simultaneously – penetrating into each bean’s core while dissolving caffeine molecules – before moving back out again as CO2. Finally, once decaffeinated coffee beans have been produced they can be dried, roasted and sold!