Mass Spectrometry-Based Flavor Monitoring of Peruvian Chocolate Fabrication Process

Characterization of fine-flavor cocoa in parent-hybrid combinations using metabolomics approach

Fine-flavored cocoa is generally characterized by fresh bean color and sensory characteristics. However, these methods cannot be applied to progenies/hybrids because their colors may vary depending on their parents. Additionally, sensory evaluation lacks universal quality standards, necessitating robust complementary characterization methods. This study aimed to characterize the fine-flavor cacao in parent-hybrid combinations using widely targeted Gas Chromatography-Mass Spectrometry (GC-MS) and bean phenotype analysis. Fine-flavored cacao exhibits white-bean characteristics and a lighter color than forastero. Conversely, the hybrids displayed varying percentages of fresh bean color. Caffeine and organic acids (malic acid, fumaric acid, citric acid, lactic acid, and tartaric acid) were found to correspond to the characteristics of fine-flavored cacao. Each parent-hybrid combination demonstrated distinct flavor characteristics, with the ICCRI03-hybrid emerging as a promising clone, exhibiting flavor characteristics similar to those of its female parent (fine-flavor cacao). This information on flavor characteristics will be beneficial for further fine-flavored cacao selection.

Sensory attributes of fine flavor cocoa beans and chocolate: A systematic literature review

Fine flavor cocoa (FFC) is known for its unique flavor and aroma characteristics, which vary by region. However, a comprehensive overview of the common sensory attributes used to describe FFC beans and chocolate is lacking. Therefore, a systematic review was conducted to analyze existing literature and identify the most commonly used sensory attributes to describe FFC beans and chocolate. A systematic search of the Web of Science and Scopus databases was conducted in May 2023, and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed to ensure transparency and reproducibility. This review summarizes the origins of cocoa and explores their unique flavor profiles, encompassing caramel, fruity, floral, malty, nutty, and spicy notes. Although some origins may exhibit similar unique flavors, they are often described using more specific terms. Another main finding is that although differences in sensory attributes are anticipated at each production stage, discrepancies also arise between liquor and chocolate. Interestingly, fine chocolate as the final product does not consistently retain the distinctive flavors found in the liquor. These findings emphasize the need for precise descriptors in sensory evaluation to capture flavor profiles of each origin. As such, the exploration of attributes from bean to bar holds the potential to empower FFC farmers and chocolate producers to effectively maintain quality control.

Changes in GC-MS metabolite profile, antioxidant capacity and anthocyanins content during fermentation of fine-flavor cacao beans from Ecuador

The fermentation of fine-flavor cacao beans is a key process contributing to the enhancement of organoleptic attributes and monetary benefits for cacao farmers. This work aimed to describe the dynamics of the gas chromatography-mass spectrometry (GC-MS) metabolite profile as well as the antioxidant capacity and anthocyanin contents during fermentation of fine-flavor cacao beans. Samples of Nacional x Trinitario cacao beans were obtained after 0, 24, 48, 72, 96, and 120 hours of spontaneous fermentation. Total phenolic content (TPC), ferric reducing antioxidant power (FRAP), and total anthocyanin content were measured by ultraviolet-visible (UV-Vis) spectrophotometry. Volatiles were adsorbed by headspace solid phase microextraction (HS-SPME) while other metabolites were assessed by an extraction-derivatization method followed by gas chromatography-mass spectrometry (GC-MS) detection and identification. Thirty-two aroma-active compounds were identified in the samples, including 17 fruity, and 9 floral-like volatiles as well as metabolites with caramel, chocolate, ethereal, nutty, sweet, and woody notes. Principal components analysis and Heatmap-cluster analysis of volatile metabolites grouped samples according to the fermentation time. Additionally, the total anthocyanin content declined during fermentation, and FRAP-TPC values showed a partial correlation. These results highlight the importance of fermentation for the improvement of the fine-flavor characteristics of cacao beans.

Monitoring Changes in the Volatile Profile of Ecuadorian Cocoa during Different Steps in Traditional On-Farm Processing

The present work was conducted to evaluate the volatile profile of Ecuadorian Forastero, CCN-51, ETT103 and LR14 cocoa beans during traditional fermentation in laurel wood boxes followed by a sun-drying process. Fifty-six volatiles were identified with HS-SPME-GC-MS. Aldehydes, alcohols and ketones were the compounds that mainly characterized the fresh cocoa. The main compounds formed during the anaerobic fermentation step were esters and acids, while in the aerobic fermentation step, an increase in ester-, aldehyde- and acid-type compounds was observed. Finally, after the drying step, a notable increase in the acid (i.e., acetic acid) content was the predominant trend. According to the genotypes, ETT103 presented high contents of terpenes, alcohols, aldehydes and ketones and low contents of unfavorable acid compounds. The CCN-51 and LR14 (Trinitarian) varieties stood out for their highest amounts in acids (i.e., acetic acid) at the end of primary processing. Finally, the Forastero cocoa beans were highlighted for their low acid and high trimethylpyrazine contents. According to the chemometric and Venn diagram analyses, ETT-103 was an interestingly high-aromatic-quality variety for cocoa gourmet preparations. The results also showed the need for good control of the processing steps (using prefermentative treatments, starter cultures, etc.) on Ecuadorian genotypes of Trinitarian origin.

Impact of the pre-drying process on the volatile profile of on-farm processed Ecuadorian bulk and fine-flavour cocoa varieties

Aiming to improve the quality of cocoa, preconditioning of cocoa after harvesting and before fermentation has become an on-farm processing step of great interest in recent times. The present work aimed to evaluate the influence of a pre-drying process on the volatile composition of Ecuadorian bulk (Forastero and CCN-51) and fine-flavour (ETT103 and LR14) cocoa at the end of primary processing. A total of 63 volatile compounds including aldehydes, alcohols, acids, ketones, esters, terpenes, lactones and other miscellaneous compounds were identified in cocoa samples by HS-SPME-GC-MS. The use of a pre-drying step revealed a varietal homogenization and a reduction in the fermentation time, making this preconditioning step an inexpensive and attractive option for farmers. Moreover, different varietal behaviour was observed after pre-drying, the fine-flavour varieties obtaining a clear improvement in aromatic quality with higher levels of compounds imparting positive notes.

Link between Flavor Perception and Volatile Compound Composition of Dark Chocolates Derived from Trinitario Cocoa Beans from Dominican Republic

The chemical composition of dark chocolate has a significant impact on its complex flavor profile. This study aims to investigate the relationship between the volatile chemical composition and perceived flavor of 54 dark chocolate samples made from Trinitario cocoa beans from the Dominican Republic. The samples were evaluated by a trained panel and analyzed using gas chromatography-mass spectrometry (GC-MS) to identify and quantify the volatile compounds. Predictive models based on a partial least squares regression (PLS) allowed the identification of key compounds for predicting individual sensory attributes. The models were most successful in classifying samples based on the intensity of bitterness and astringency, even though these attributes are mostly linked to non-volatile compounds. Acetaldehyde, dimethyl sulfide, and 2,3-butanediol were found to be key predictors for various sensory attributes, while propylene glycol diacetate was identified as a possible marker for red fruit aroma. The study highlights the potential of using volatile compounds to accurately predict chocolate flavor potential.

The impact of roasting on cocoa quality parameters

Roasting is an essential process in cocoa industry involving high temperatures that causes several physicochemical and microstructural changes in cocoa beans that ensure their quality and further processability. The versatility in roasting temperatures (100 - 150 °C) has attracted the attention of researchers toward the exploration of the effects of different roasting conditions on the color, proximal composition, cocoa butter quality, concentration of thermolabile compounds, formation of odor-active volatile organic compounds, generation of melanoidins, production of thermal processes contaminants in cocoa nibs, among others. Some researchers have drowned in exploring new roasting parameters (e.g., the concentration of water steam in the roasting chamber), whilst others have adapted novel heat-transfer techniques to cocoa nibs (e.g., fluidized bed roasting and microwaves). A detailed investigation of the physicochemical phenomena occurring under different cocoa roasting scenarios is lacking. Therefore, this review provides a comprehensive analysis of the state of art of cocoa roasting, identifies weak and mistaken points, presents research gaps, and gives recommendations to be considered for future cocoa studies.

Investigation of the effect of processing on the component changes of single-origin chocolate during the bean-to-bar process

Chocolate is one of the most popular sweets in the world. In recent years, the bean-to-bar process for chocolate production has attracted global attention. Bean-to-bar is a method of managing the whole production process from cocoa beans to chocolate bars, including single-origin chocolate (SOC). Many manufacturers aim to produce high-quality chocolate to maximize the flavor of cocoa beans. However, chocolate compounds are very complex due to many processes, and there are a limited number of studies on the SOC produced from the bean-to-bar process. Therefore, understanding the effects of processing is important for the growth of the chocolate industry. The objective of this study was to investigate the processing effect on the component changes of SOC during the bean-to-bar process. In this study, the component changes during the bean-to-bar process were monitored using gas chromatography/mass spectrometry (GC/MS). Then, the characteristics of SOC from five regions in Indonesia were further investigated. Lastly, the component profiles were combined with the data obtained from sensory evaluation. Our results showed that the influence of the manufacturing process was greater than that of the difference in the cocoa production area. Moreover, 1-pentanol, raffinose, and heptanoic acid were correlated with sweetness and dairy flavor, whereas glutamic acid, tartaric acid, 3-methyl-2-butanone, mannitol, and ethyl cinnamate were correlated with bitterness, astringency, and cocoa flavor, which were shown to be affected by fermentation, roasting, and sugar addition. This information might provide a basis for improving the chocolate production process and its quality related to the component profiles.

Analysis of Volatiles in Food Products

The evaluation of volatiles in food is an important aspect of food production. It gives knowledge about the quality of foods and their relationship to consumers’ choices. Alcohols, aldehydes, acids, esters, terpenes, pyrazines, and furans are the main chemical groups that are involved in aroma formation. They are products of food processing: thermal treatment, fermentation, storage, etc. Food aroma is a mixture of varied molecules. Because of this, the analysis of aroma composition can be challenging. The four main steps can be distinguished in the evaluation of the volatiles in the food matrix as follows: (1) isolation and concentration; (2) separation; (3) identification; and (4) sensory characterization. The most commonly used techniques to separate a fraction of volatiles from non-volatiles are solid-phase micro-(SPME) and stir bar sorptive extractions (SBSE). However, to study the active components of food aroma by gas chromatography with olfactometry detector (GC-O), solvent-assisted flavor evaporation (SAFE) is used. The volatiles are mostly separated on GC systems (GC or comprehensive two-dimensional GCxGC) with the support of mass spectrometry (MS, MS/MS, ToF–MS) for chemical compound identification. Besides omics techniques, the promising part could be a study of aroma using electronic nose. Therefore, the main assumptions of volatolomics are here described.