Ozonation of agri-food products for reducing mycotoxin contamination: challenges in grains and particulates processing.

This study evaluated differences in the efficiency of ozonation process to reduce the natural contamination of two mycotoxins, deoxynivalenol (DON) and zearalenone (ZEN), in wheat grains and particulate products. Three different products were used, each one representing a different structure and mycotoxin distribution: (1) wheat grains, with natural mycotoxin distribution inside and among the grains; (2) homemade pellets, with homogenous mycotoxin distribution; (3) ground homemade pellets, with homogeneous mycotoxin distribution, and smaller particles. The ozonation of naturally contaminated wheat grains did not reduce the concentrations of DON and ZEN. When the variability of contamination among replicates was reduced by the production of homemade pellets showed, the ozonation provides a reduction of 14% of ZEN concentration. Reducing the size of particles by grinding the homemade pellets, a reduction of DON (11%) and ZEN (31%) was observed, which was evidenced by the higher ozone consumption during the process. Therefore, some limitations of ozonation of grains and particulate products, such as particle dimensions and distribution of natural contamination of mycotoxins affect the degradation of DON and ZEN under real conditions. Because of this, further studies to evaluate the effectiveness of ozonation should also be performed in samples naturally contaminated to produce robustness results.

Evaluation of ozone technology as an alternative for degradation of free gossypol in cottonseed meal: a prospective study.

Free gossypol is a toxic compound which naturally occurs in cottonseed and its derivates, affecting animal and possibly human health. Consequently, alternatives for gossypol destruction must be evaluated. This work evaluated the emerging technology of ozone processing for free gossypol destruction in cottonseed meal. Ozonation was carried out in the actual cottonseed meal and also a model system, designed to describe the involved mode of action. The model system consisted of glass pearls beads covered with free gossypol. Ozonation was performed in two ways: as a static process, i.e., without homogenising the sample after placing them in the reactor, and also homogenising it. Ozone degraded free gossypol in all the systems, but reaching different levels. Free gossypol reduction was higher in the model system than the cottonseed meal, and higher in the homogenised processing than the static one: cottonseed meal in homogenised (56%) and static (25%); model system homogenised (98%) and static (80%). The obtained differences suggest a problem of gas penetration in the solid particles, the effect of unexposed surfaces due to contact areas, and the reaction with other organic molecules further than the target. Ozonation is a promising technique for gossypol degradation in cottonseed meal, but additional strategies are needed to optimise the ozonation process and evaluate toxicological aspects.