Recently, in Brazil, corn ethanol industries are being installed and the integration with sugar/energy-cane has been proposed, using bagasse for cogeneration and the juice to dilute the corn. However, this integration may have some limitations, such as the quality of the cane juice and potential contamination by microorganisms brought with the cane from the field. In this article, we first tested the effects of mixing energy cane juice with corn on fermentative parameters. We also assessed the effects of Lactobacilli. contamination on organic acids produced during the fermentation and fermentation parameters and proposed the use of ionizing radiation to replace antibiotics as a disinfection control method. Our results showed that mixing energy cane juice with corn does not have any negative effect on fermentation parameters, including ethanol production. The contamination with Lactobacilli. considerably increased the production of acetic, lactic, and succinic acid, reducing the pH and ethanol content from 89.2 g L⁻¹ in the sterilized treatment to 72.9 g L⁻¹ in the contaminated treatment. Therefore, for the integration between corn and cane to be applied on an industrial scale, it is essential to have effective disinfection before fermentation. Ionizing radiation (20 kGy) virtually disinfected the wort, showing itself to be a promising technology; however, an economic viability study for adopting it in the industry should be carried out.

The Very High Gravity (VHG) fermentation is a technology that can lead to a reduction in waste generation, a reduction in energy consumption and GHG emissions and several technical, economic, and environmental advantages. Having, as a limiting factor, yeast tolerance to the most diverse stressors in the fermentation medium. To overcome this limitation, the aim of the work was to verify the potential protective effect of silica ^(+A) on Saccharomyces cerevisiae (Ethanol Red^®) submitted to VHG fermentation. Initially, an adaptive test to VHG fermentation was carried out, with 5 cell recycles in musts from sugar cane syrup. Each recycle was subjected to the treatments, in quadruplicate: T1C (control) - Wort without silica supplementation; T2S100- Wort with supplementation of 100 mg L^-1 of silica and T3S300- Wort with supplementation of 300 mg L ^-1 of silica. As a result, the T3S300 treatment in the adaptive test, showed viability of 77.5 to 81.55%; biomass production from 8.1 to 10.0 g L^-1; yield from 90.0 to 95.3% and productivity from 7.3 to 10.9 mL L^-1h^-1. In conclusion, the treatment of the wort with silica ^(+A) (100 and 300 mg L^-1) has an effect protector on yeast and may present positive responses in VHG fermentations.

O Simpósio Nacional de Bioprocessos (SINAFERM) é um tradicional evento bianual que reúne profissionais com diferentes formações e que atuam nas várias etapas dos bioprocessos. Em 2015 o evento chega a sua 20ª edição.