Autenticação de cafés solúveis usando fingerprints espectrais UV-VIS e NIR

Abstract

Instant coffee, like any other food product, is subject to deterioration over time, which leads to changes in flavor, aroma, and texture. Additionally, the decaffeination process can also affect their overall sensory characteristics and shelf life. In this work, UV-VIS spectroscopy (for analysis of diluted instant coffee) and NIR spectroscopy (for direct non-destructive analysis of the powder, using a portable device) were employed to authenticate the shelf life and decaffeination process of soluble coffee samples using Data-Driven Soft Independent Modeling of Class Analogy (DD-SIMCA). In the first authentication study regarding shelf life, a total of 201 samples were used, while in the second authentication study concerning the decaffeination process, a total of 148 samples were used. For both authentication approaches, the best results were achieved with sensitivities ranging from 95.0 to 97.1% in the training set, while sensitivities and specificities between 96.2 and 100% were obtained in the test set. Considering the UV-VIS data in both studies, the best results were obtained using the Standard Normal Variate (SNV) as a preprocessing technique. Meanwhile, for NIR data, the first and second derivatives of Savitzky-Golay with a second-order polynomial and a 21-point window led to the best results for the first and second studies, respectively. As a result, by authenticating instant coffee samples in terms of shelf life and the decaffeination process, manufacturers can ensure that consumers are enjoying a product with freshness and quality. Therefore, the proposed methodology can contribute to consumer safety, enhance brand reputation, ensure regulatory compliance, and improve production and distribution efficiency. Additionally, it can assist in stock management planning, reduce waste, and minimize financial losses, benefiting both manufacturers and the environment, and contributing to sustainable practices.