Impact of eBeam processing on raw milk

Despite containing relatively high numbers of microorganisms, including pathogens, the consumption of raw milk is on the rise in the United States. A study published in the Journal of Food Science explores the effects of electron beam processing on the nutrient profile and sensory attributes of raw milk. Electron beam (eBeam) processing is a nonthermal pasteurization food processing technology.

The researchers exposed raw milk samples to eBeam doses of 1 and 2 kGy, since previous studies had shown that 2 kGy is suitable for raw milk pasteurization. The untreated and eBeam-treated raw milk samples were analyzed to detect changes in lactose, vitamin B2, vitamin B12, and calcium concentrations. They also investigated the possible breakdown of casein and whey proteins and lipid oxidation along with the formation of volatile aroma compounds.

The researchers found that even though vitamin B2 showed a 31.6% decrease in concentration, the B2 content in eBeam-pasteurized raw milk met all the U.S. Dept. of Agriculture (USDA) nutritional guidelines. Even though there were no indications of lipid oxidation after the 2-kGy eBeam treatment, there was lipid oxidation (58%) after seven days of refrigerated storage. However, based on the GC-olfactory analysis, the lipid oxidation did not necessarily result in the development of a wide variety of off-odors.

The researchers concluded that the results “suggest that eBeam pasteurization of raw milk does not adversely affect nutrient levels.” While some off-odors were detected, the researchers believe “it would be worthwhile to evaluate whether incremental eBeam dosing would further reduce the chances of any off-odors occurring.”

Abstract