A novel digital image method for determination of reducing sugars in aged and non-aged cachacas employing a smartphone

For the first time, a method is proposed for colorimetric determination of reducing sugars in cachaca employing digital image and a smartphone as detector. The method was based on the reduction of Cu(II) to Cu(I) by sugars and followed by the formation of a colored Cu(I)-Neocuproine complex. A calibration curve was linear from 0.1 to 15 g L-1 for glucose and fructose with limits of detection of 0.012 g L-1 and 0.010 g L-1, respectively. It was observed that the non-aged cachacas, known for having inferior flavors and aromas, had a reducing sugar content three times higher than the aged cachacas, once a common practice among producers is to add sugar to adjust sensory deficits in the final product. Furthermore, the method is simple, does not require complex technical knowledge and it could be used as a tool to check possible fraud, adulteration or non-compliance to the law.

Automated summary

A novel method using digital image and a smartphone as detector was proposed for colorimetric determination of reducing sugars in cachaca. The method is simple, does not require complex technical knowledge, and could be used as a tool to check possible fraud, adulteration, or non-compliance to the law. Additionally, it was found through experiments that non-aged cachacas have three times higher reducing sugar content compared to aged cachacas, as producers often add sugar to adjust sensory deficits in the final product.