Efeitos do tratamento UV-C em grãos estocados de malte de trigo escuro

Abstract

Being the beer the third most consumed beverage in the world, its ingredients of their production deserve special attention. In order to be transformed into beer, the cereal grain needs to go through the malting process, with wheat being one of the most used cereals due to its high carbohydrate content. In its storage, it can occur the appearance of pests and its treatment is carried out with pesticides sometimes used in concentrations above the limit. Under these conditions, UV-C radiation presents as an alternative to the treatment of malt grains in their storage. Thus, this work aimed to evaluate the effect of UV-C treatment on the Plodia interpunctella insect by using 2 18W Phillips ™ germicidal lamps with a majority wavelength of 254 nm. Physicochemical and microbiological effects on treated malt were evaluated in comparison to the raw sample, and results were submitted to ANOVA (Tukey, p<0.05). The three treatments performed at distances of 8cm, 16cm and 30cm from the light source were satisfactory in inhibiting the insect’s pupae. The titratable acidity, moisture content, soluble solids and colorimetry were determined. The pH ranged between 5.52 and 5.61. The titratable acidity showed a significant difference ranging from 0.65 to 1.69. The moisture content ranged from 7.72% to 8.21%. Soluble solids varied from 25.31º to 25.43º Brix. The colorimetry showed a variation from 39.38 to 41.46 in the L* parameter, 8.62 to 11.80 in the a* parameter and 17.32 to 19.96 in the b* parameter. As for the microbiological analyses, there was a significant difference between the treatments and the control, showing that Treatments 2 and 3 (distances of 8cm and 16cm from the light source) are more effective in reducing fungal infection, with an average infection content of 6.67%.