Impact of Preharvest and Postharvest on Color Changes during Convective Drying of Mangoes.

Alioune Diop,Nafissatou Diop Ndiaye,Frédéric Chiroleu,Christian Mertz,Marc Chillet,Jean-Michel Méot,Mady Cissé,Mathieu Léchaudel

doi:10.3390/foods10030490

Abstract

The purpose of this study was to evaluate the impact of the harvest stage, ripening conditions and maturity on color changes of cv. ‘Cogshall’ and cv. ‘Kent’ variety mangoes during drying. A total of four harvests were undertaken, and the fruits were ripened at 20 and 35 °C for five different ripening times at each temperature. At each ripening time, mangoes were dried at 60 °C/30% RH/1.5 m/s for 5 h. A wide physico-chemical and color variability of fresh and dry pulp was created. The relationships according to the L*, H* and C* coordinates were established using mixed covariance regression models in relation to the above pre- and postharvest (preprocess) parameters. According to the L* coordinate results, browning during drying was not affected by the preprocess parameters. However, dried slices from mangoes ripened at 35 °C exhibited better retention of the initial chroma, and had a greater decrease in hue than dried slices from mangoes ripened at 20 °C. However, fresh mango color, successfully managed by the pre- and postharvest conditions, had more impact on dried mango color than the studied parameters. The preprocess parameters were effective levers for improving fresh mango color, and consequently dried mango color.

Highlights

Drying represents one of the most common unit operations in the agri-food industry, for product stabilization
Our data confirm the results found by Léchaudel and Joas [47], which demonstrate that the Cogshall variety mangoes harvested before 115 days after blooming (DAB corresponding to the green-mature stage) have a total soluble solids content of less than 10
The maximum Brix values after ripening were attained by mangoes harvested at later maturity stages (Batches 2 and 4)

Summary

Introduction

Drying represents one of the most common unit operations in the agri-food industry, for product stabilization. It greatly reduces the weight of the products, lowers water activity and slows microbe growth, as well as chemical and bio-chemical reactions. Color is generally the top purchase criterion for fruit [10], and for dried mangoes [11] in particular. Without any added sugar or sulfites, are regarded as more dietetic and having a stronger taste [11]. Browning causes a color change in the mango slices from yellow-orange to brown-black, and when over-developed leads to rejection by consumers

Objectives

Results

Conclusion