One goal of Sapers' research is to increase the effectiveness of the commercial materials by adding combinations of either acids and detergents or alkaline materials and surfactants. By themselves, these treatments are not a major improvement on chlorine, but do increase in effectiveness when heated to 120 . A treatment showing even more promise is adding hydrogen peroxide to some of the commercial formulations and then heating the mixture. This treatment comes close to the five-log kill step likely to be included in the upcoming FDA regulations. Buchanan has found that E. coli which infiltrate the apple's flesh cannot be killed by any known washing method.
Temperature makes a difference, too.
If apples are warm and water containing E. coli is cold, the bacteria can penetrate the apple, possibly through the blossom end, and reach the core. At that point, nothing will kill the bacteria except pasteurization. Buchanan is looking at how bacterial resistance is induced by stress. When bacteria are exposed to acid or to heat, it can be induced to become more resistant to other traumas in the future. At Cornell, the focus is to determine how the bacteria get into the fruit and exploring alternate processing methods for the production of safe cider.