Irradiation of hot peppers to improve their hygienic quality

Irradiation of hot peppers (Capsicum) was carried out in a facility with a double plaque 60Co source. The dose distribution was reasonably uniform and symmetrical, with a Dmax:Dmin ratio of 1.266. Bacteriological examination showed that the total number of microorganisms was reduced by several orders of magnitude and that the majority of moulds and coliforms was killed by a medium dose of 5 kGy, with no loss of capsaicin content. The variation in concentration of free radicals measured by electron spin resonance in the irradiated and the non-irradiated hot peppers did not deviate from the same order of magnitude, ranging from 2.4x1014 to 4.0x1014 spin quantum number per gram. However, the concentration increased with dose, reaching a peak at 8 kGy. The life-span of the free radicals appeared to increase after irradiation. No insect larvae or spoiled hot peppers were found after irradiation and 9 months of storage under ambient conditions. The organoleptic properties remained unchanged; consequently, the peppers received good evaluation from the consumers. It is thus evident that the irradiated, dried hot peppers are of good quality, are acceptable to a wide variety of consumers and meet international trade standards, and that the technology will be of social and economic benefit to the province. (author). 12 refs, 4 figs, 3 tabs