As reviewed in previous chapters, new plant varieties that are potential food sources are being developed with recombinant DNA technologies (Harlander 1991; Kessler et al. 1992; Olempska-Beer et al. 1993). On the basis of these techniques, specific genetic modifications that could not have been accomplished through traditional breeding techniques have been achieved, including the expression of proteins into plants from other species. Several potential foods that have been derived from these new plant varieties by recombinant DNA technologies and are either commercially available or approaching commercial introduction (Table 1). Because genes governing these new traits code for proteins that are ordinarily not present in that plant, there is concern about the effects of the transferred proteins on individuals ingesting them (Harlander 1991; Kessler et al. 1992; Olempska-Beer et al. 1993). A major concern is the potential of these transferred proteins as food allergens (Kessler et al. 1992; Olempska-Beer et al. 1993).