Author(s): Teixeira, Raquel ; Ribas, Tânia C. F. ; Almeida, André ; Pintado, Manuela ; Rangel, António O. S. S.
Date: 2025
Persistent ID: http://hdl.handle.net/10400.14/55671
Origin: Veritati - Repositório Institucional da Universidade Católica Portuguesa
The growing interest in protein hydrolysates highlights the need for fast and reliable analytical methods to assess their nutritional and functional properties. Total protein quantification is a key parameter for characterizing by-products, monitoring hydrolysis processes, and evaluating hydrolysates. In this work, a sustainable flow-based spectrophotometric method was developed and optimized using the Biuret method [1]. The flow injection analysis (FIA) system employs a double injection strategy in a continuous stream, significantly reducing reagent consumption compared to the conventional procedure, with a 75% decrease in Biuret reagent and an 83% reduction in sodium hydroxide, while maintaining analytical accuracy (Figure 1). Optimization of flow and chemical parameters enabled robust performance across different matrices used during enzymatic hydrolysis. The dynamic range of the method was 0.100 results were in agreement with those obtained with the reference method (<10% deviation). Additionally, the herein proposed method reduced the analysis time from 30 to 3 minutes per sample (triplicate). The proposed protocol offers a faster, greener, and reliable tool for the food industry, supporting sustainability in quality control and nutritional evaluation.
