Comparison of Vacuum Treatments and Traditional Cooking Using Instrumental and Sensory Analysis

Abstract

The purpose of this work was to compare carrots with similar firmness cooked by traditional cooking and two vacuum treatments: sous-vide (SV) and cook-vide (CV). As a first step, consumers determined the preferred level of firmness for carrots cooked by traditional cooking (boiling). This level corresponded to instrumental firmness of 2.8 N in phloem tissue and 4.1 N in xylem tissue. Response surface methodology (RSM) established the pairing conditions of time (22 to 78 min) and temperature (78 to 92 °C) to study the effect of both factors on the firmness of carrots with sous-vide and cook-vide treatments. In both treatments, the instrumental firmness of phloem and xylem samples was measured and modeled. No significant differences were found in firmness values between phloem and xylem tissue of samples cooked by vacuum treatments (CV and SV). For CV treatment, firmness decreased linearly with time and temperature, while for SV treatment it followed a second-order model. Based on the model, conditions of time and temperature to achieve the preferred firmness (2.8 N) were selected for both treatments. Finally, consumers compared the sensory properties of carrots cooked by traditional cooking, sous-vide, and cook-vide with paired comparison tests evaluating three pairs of samples. Carrots cooked by cook-vide were considered less tasty than sous-vide and traditional cooking carrots. Carrots using traditional cooking were firmer than those obtained with SV and CV treatments. Carrots cooked by traditional and sous-vide treatments were preferred to cook-vide ones for the taste.