Industry & Materials
Sterilised spices and reliable curing salts
The problem
Spices and other natural seasonings carried bacteria, moulds and insect eggs into cured meat, and curing salts broke down before they could act evenly.
The innovation
A vacuum chamber that drew ethylene oxide through spices to sterilise them cold, and a flash-drying process that combined curing salts into a single crystal so they acted in the right order.
How it worked
Vacuum opens the plant material; the gas penetrates and kills organisms; the vacuum then removes the residue. Flash-drying encases the slower-acting salt inside the faster one.
Why it mattered
Longer, safer shelf life across the processed-food industry, and a sterilisation approach later adapted for medical supplies.
The legacy
Hall's patents in preservation, antioxidants and protein hydrolysates shaped the industrial food chemistry that supermarkets assume.
You use this today
Cured meats, packaged seasonings and shelf-stable fats.
Sources
Granted patents of Lloyd A. Hall, sterilisation and curing series
Primary recordLloyd Hall inductee record
Institutional record
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