The role of conching in chocolate flavor development: A review

Abstract

Chocolate is an indulgent product whose consumption is mostly motivated by its alluring sensory properties. Among them, flavor stands as the key driver for consumer preference and purchase intention. Flavor is a complex multimodal perception whose discrimination depends mostly on the retronasal aromas associated with the presence of odor-active compounds in the matrix. The development of chocolate flavor relies on several factors, ranging from intrinsic properties of raw materials to formulation and processing conditions. As the last step of liquid chocolate manufacture, conching develops proper fluidity/texture and finetunes flavor, by means of intensive mixing and continuous heating of chocolate mass for several hours. Time and temperature are the main parameters determining the extent of conching effects upon flavor, despite factors such as ventilation, energy input onto chocolate mass, and configuration of conching machine being also relevant to some of the physicochemical mechanisms involved in flavor modification. Overall, conching impacts chocolate flavor by either changing the concentration of key odor-active compounds or modifying their distribution throughout the matrix, affecting their binding to other components and, ultimately, their rate of release during ingestion. The present review aims to gather evidence on the physicochemical transformations promoted by conching responsible for flavor enhancement and overall sensory quality of chocolates.

Toward Unified Flavor Quantitation in Cocoa-Based Products

“…As a result, individual concentrations could be quantified and not only the sum of both or three, which was often done in previous work. A 1:3 ratio for 2-and 3-methylbutanoic acid could be found as stated in the literature in chocolate, 22 with concentrations of 14− 5800 μg/kg determined for both analytes. The aldehydes 2and 3-methylbutanal could be detected at concentrations between 24 and 3500 μg/kg, and the odor-active compounds butanoic and hexanoic acid were present at concentrations of 95−2479 and 986−2951 μg/kg, respectively; comparatively low levels of 2−83 μg/kg were found for nonanal.…”

Can Chocolate Be Classified as an Ultra-Processed Food? A Short Review on Processing and Health Aspects to Help Answer This Question

“…This phase is related to the final form of chocolate making, comprising the following steps: Mixing cocoa products with sugar, milk, or other ingredients according to chocolate type and formulation and the ensuing processing steps for obtaining the solid chocolate bar; After mixing, the liquid chocolate paste is refined to further reduce particle sizes, ensuring flowability and adequate sensory properties. During refining, temperatures can reach 60 °C because of viscous dissipation, but cooling is applied to reduce the temperatures so that adequate viscosity is maintained throughout the process [ 14 ]; The chocolate is then conched, which is a stirring operation at temperatures above 50 °C for a few hours to remove undesirable volatile compounds to reduce acidity and further develop flavor as well as viscosity and texture [ 41 ]. Conching is crucial in chocolate processing for the development of sensory and quality characteristics [ 42 ]; The chocolate undergoes tempering to promote adequate fat crystallization in cocoa butter’s most thermodynamically stable form [ 16 , 39 ].…”

Spatial Distribution of Cocoa Quality: Relationship between Physicochemical, Functional and Sensory Attributes of Clones from Southern Colombia

“…Another important feature highlighted by Alvarez et al [48] is the observation of an inverse or negative relationship between herbal and nutty flavor. This means that the higher the herbal attribute, the lower the nutty flavor, which could be explained by the relationship that exists between the herbal and the bad or low fermentation of the grain, since it is characterized by a green or fresh grass flavor, contrasting with what could be the development of the nutty flavor [90,91].…”