Decontamination of Dry Food Ingredients with “Soft-Electrons” (Low-Energy Electrons)
Electrons with energies of 300 keV or lower were defined as “soft-electrons”. Soft-electrons eradicated microorganisms residing on the surface of grains, pulses, spices and dehydrated vegetables, and reduced their microbial loads to levels lower than 10 CFU/g. Soft-electrons penetrated only into the surface of grains and did not significantly degrade starch molecules inside grains. The use of electrons with a higher energy and with a higher penetration capacity resulted in a higher thiobarbituric acid value (TBA, parameter for lipid oxidation) of brown rice. Milling of rice at a yield of 90% or 88% after exposure to electrons resulted in a TBA value of rice treated with electrons at 65 keV almost the same as that of untreated rice, indication that the milling process removed the portion of brown rice exposed to softelectrons. It is concluded that soft-electrons can decontaminate dry food ingredients with few adverse effects on the quality.