Roasting impact on the chemical and physical structure of Criollo cocoa variety (Theobroma cacao L)

Abstract

This work analyzed the effect of infrared roasting at 100, 150, and 200 C on the main physical and chemical changes of cocoa. Raw and roasted cocoa were analyzed using Brunauer-Emmett-Teller, Fourier transform infrared spectroscopy, modulated differential scanning calorimetry (MDSC), thermogravimetric analysis (TGA), SPME, and GC-MS. Using MDSC, the fusion of fat at around 35 C, and the desolvation of water and volatile compounds were identified. TGA detected loss of mass of various groups of chemical compounds, including those present pre-roasting and generated during roasting. The unroasted cocoa's total sugar content of 2.71% decreased to 0.64% when roasted at 200 C, whereas roasting at 200 C generated seven (7) pyrazines. Tetramethylpyrazine is the most abundant, reaching the highest concentration when roasted at 150 C, but decreases when roasted at 200 C, due to the high temperature. To obtain the maximum production of favorable pyrazines, the temperature must be controlled based on the quality objectives of the final product. Practical applicationsThe process of roasting cocoa is of great importance to the chocolate and derivatives industry. Knowledge of the chemical and physical changes that occur during roasting can help to optimize the operating conditions to obtain a better-quality product, in particular by conserving and developing the flavor and aroma of fine Criollo cocoa varieties. This will support the industrialization of fine cocoas, presenting an option for improving the economic and social development of marginalized countries and communities.

Chemical Composition and Thermogravimetric Behaviors of Glanded and Glandless Cottonseed Kernels

“…Similar to other seeds or nuts for food applications [ 45 , 47 , 82 , 83 , 84 , 85 ], roasting is a necessary heating process for enhanced use of cottonseed kernels as nutrient food products [ 23 ]. While roasting temperatures were reported in the range of 100 to 160 °C for various plant-based butters [ 86 ], the negligible CO 2 and CO bands (2400–2300 cm −1 ) in TG-FTIR spectra of Gd-k and Gl-k below 215 °C of the first shoulder in DTG curves ( Figure 5 ) suggested that the cottonseed kernels could be roasted in the temperature range without significant occurrence of decomposition (carbonization).…”

“…Heat treatments such as roasting and frying are frequently employed in the food processing of seeds and nuts to improve their sensory quality, digestibility, and microbiological safety [ 43 , 44 , 45 ]. Thus, TG analysis has been applied to detect the mass loss of various volatile compounds as well as appropriate roasting temperatures for heat treatments [ 44 , 46 , 47 ]. The coupling of TG with FTIR (i.e., TG-FTIR) has provided a unique capability to obtain the transient mass loss and evaluation of the volatile functional groups of a sample, which could not be obtained by the TG and FTIR individually [ 42 , 48 ].…”

Desenvolvimento e caracterização do perfil de compostos voláteis de casquinha de sorvete produzida com farinha da casca e amêndoa de manga Tommy Atkins

“…Estudos têm demonstrado que temperaturas entre 104 °C e 190 °C propiciam a perda de alguns compostos voláteis, mas também a formação de novos compostos (Diaconeasa et al, 2019;Kusçu & Bulantekin, 2016;Rojas et al, 2020). Alguns autores relatam que a perda de compostos voláteis pode ocorrer pela evaporação ou degradação durante o processo de obtenção em altas temperaturas (Bonneau et al, 2016;Oliver-Simancas et al, 2020b).…”

Theobromacacao Criollo var. Beans: Biological Properties and Chemical Profile

“…Among cocoa pure lines, Criollo is one of the varieties of high quality [ 9 ]. Thus, the aim of this work was to investigate the biological properties and the chemical composition of two different samples of Criollo var.…”