Stabilization of pyrocarbonic acid diesters by finely divided solids

A process for protecting and preserving an industrial material, foodstuff or beverage, comprising:

• contacting the industrial material, foodstuff or beverage with a composition comprising
• a) one or more dialkyl pyrocarbonates selected from the group consisting of dimethyl pryrocarbonate, diethyl pyrocarbonate, and mixtures thereof;
• and
• b) boron trioxide in an amount of from 0.01 to 100,000 ppm, based on the one or more dialkyl pyrocarbonates, wherein the boron trioxide has a particle size, determined by screening, of ≦32 μm, and
• whereby chemical and/or thermal degradation reactions of the dialkyl pyrocarbonates are reduced.