Roasted Cocoa Beans Research Articles

Evaluation of Breaking and Deshelling Machine of Roasted Cocoa Beans

The manual cracking and separation of cocoa beans' husk result in low working productivity, a high percentage of broken beans, and the difficulty of separating cocoa nibs from the husk. This poses a challenge for both farmers and industrial players in cocoa bean management, leading to the development of a cocoa bean dehusking machine (desheller). This study was conducted to analyze the performance of the cocoa bean dehusking machine. The research involved motor speeds of 500, 700, and 900 rpm, combined with roasted cocoa bean grades AA, A, and B. The observed parameters included working capacity, yield, nib percentage, percentage of husk adhering to nibs, power transmission efficiency, and power requirements. The working capacity of the cocoa bean deshelling machine ranged from 17,413 to 41,481 kg/h, with yields between 73.83% and 80.83%. The nib percentage varied from 92.13% to 98.61%, while the percentage of husk adhering to nibs ranged from 1.08% to 6.92%. Power transmission efficiency was between 92.24% and 94.14%, and power requirements ranged from 601.33 to 645.33 watts. The best treatment in this study was found at a motor speed of 900 rpm with cocoa bean grade of AA. Keywords: Desheller, Nibs, Roasted cocoa beans, Shell, Yield

Chocolates Produced with Unroasted and Roasted Cocoa Beans: A Comparative Study of the Preservation of Bioactive Compounds

The aim of the present study was to evaluate the effect of roasting and cocoa mass content on the composition of chocolates. Chocolate formulations were developed (40, 50, 60 and 70% cocoa solids) using unroasted and roasted cocoa beans, and analyses were performed: physicochemical, chemical composition, antioxidant capacity, procyanidin content, total phenolic compounds, quantification of theobromine, caffeine, catechin and epicatechin by high performance liquid chromatography (HPLC) and spectroscopic profile by mid-infrared spectroscopy (MIR). The results revealed that higher values of total phenolics, epicatechin and procyanidins, were obtained in chocolates produced with unroasted cocoa beans, with a significant difference in relation to those with roasted cocoa beans. It was observed that increasing the percentage of cocoa in the formulations caused an increase in the content of bioactive compounds. The use of MIR in the differentiation of chocolate samples produced with roasted and unroasted cocoa beans obtained a positive result. This technique associated with principal component analysis (PCA) enabled the separation of chocolates according to the type of cocoa bean (roasted and unroasted) used in production, confirming its importance for a quick evaluation of the parameters.

Development and Performance Evaluation of a Cocoa Bean Sheller cum Winnower

Cocoa (Theobroma cacao L.) is a commercial plantation crop in India. It is the main raw material in the production of chocolates, cosmetics, health drinks, pharmaceuticals etc. Shelling is one of the primary unit operation and critical step in the processing of chocolate. It affects the quality of the cocoa nibs in terms of flavor and purity. The present study focuses on the development of a cocoa bean sheller cum winnower and its performance evaluation in terms of percentage of cracked and uncracked beans, shelling efficiency, capacity, cleaning efficiency and energy requirement. Roasted cocoa beans were shelled using the developed cocoa bean sheller, which were further subjected to winnowing operation using cocoa bean winnower to separate the shells from the nibs. The shelling efficiency of the developed cocoa bean sheller and cleaning efficiency of the winnower were found to be 98 % and 90.38% respectively.

Microwave Roasting as an Alternative to Convection Roasting: Sensory Analysis and Physical Characterization of Dark Chocolate.

Roasting cocoa beans by means of microwave radiations seems to be a potential alternative to convection roasting, but little is known about the impact of this method on the perceived flavor profile of the chocolate. Therefore, this research focused on revealing the flavor perception of chocolate produced with microwave roasted cocoa beans assessed by both a trained panel and chocolate consumers. Samples of 70% dark chocolate produced from cocoa beans microwave roasted at 600 W for 35 min were compared with samples of 70% dark chocolate produced from cocoa beans convectively roasted at 130 °C for 30 min. Non-significant differences (p > 0.05) in the measured physical properties, such as color, hardness, melting, and flow behavior, showed that chocolate produced from microwave roasted cocoa beans can exhibit the same physical qualities as convection roasted chocolate. Moreover, combined discriminative triangle tests, with 27 judgements in total, performed by a trained panel, showed that each type of chocolate exhibited distinctive characteristics (d'-value = 1.62). Regarding the perceived flavor, "cocoa aroma" was cited as significantly higher for the chocolate produced from microwave roasted cocoa beans (n = 112) compared to chocolate produced from convection roasted cocoa beans (n = 100) by consumers. Both preference and willingness to buy were higher, though insignificant at a 5% level, for the microwave roasted chocolate. A final potential benefit (studied in this research) of microwave roasting cocoa beans is the reduced energy consumption, which was estimated at 75%. Taking all these results together, the microwave roasting of cocoa is shown to be a promising alternative to convection roasting.

Key Aromatic Volatile Compounds from Roasted Cocoa Beans, Cocoa Liquor, and Chocolate

The characteristic aromas at each stage of chocolate processing change in quantity and quality depending on the cocoa variety, the chemical composition of the beans, the specific protein storage content, and the polysaccharides and polyphenols determining the type and quantity of the precursors formed during the fermentation and drying process, leading to the formation of specific chocolate aromas in the subsequent roasting and conching processes. Bean aroma is frequently profiled, identified, and semiquantified by headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPMEGC-MS) and by gas chromatography olfactometry (GC-O). In general, the flavors generated in chocolate processing include fruity, floral, chocolate, woody, caramel, earthy, and undesirable notes. Each processing stage contributes to or depletes the aroma compounds that may be desirable or undesirable, as discussed in this report.

Hedonic Test Analysis and Feasibility of The Selling Price of Cocoa Seed Waste Products in PT XYZ Kulon Progo, Yogyakarta

Innovative use of waste into herbal beverage products the waste treatment process starts from the stage of roasting cocoa beans, breaking the beans and peeling the skin, sorting, drying, preparation of packaging and materials, filling and mixing, giving silica gel and labelling the expiration date. The raw materials needed are cocoa bean husk, dried cardamom, and cinnamon powder. While the packaging material uses PET plastic bottle packaging. Before the product is marketed, it is necessary to conduct a feasibility analysis of the selling price. The analysis shows that the selling price of chocolate product of Rp. 15,000 is feasible because profit taking is 48% with the selling price per unit more than the cost per unit. The net profit margin of chocolate product of 32.6% means that the company is considered efficient in determining the selling price of its products and successfully controlling costs in it because the NPM figure is > 5%. Hedonic tests were also conducted to determine consumer acceptance of the product through a hedonic test of 20 panelists based on the parameters of color, aroma, taste, and packaging. The hedonic test scale 1 shows that consumers do not like it very much, a scale 2 does not like it, a scale 3 likes it, and a scale 4 likes it very much. The average level of preference for color parameters is 3.58, aroma is 3.31, taste is 3.47, and packaging is 3.84 which indicates that the panelists like these 4 parameters.

Flavor diversification of dark chocolate produced through microwave roasting of cocoa beans

The impact of microwave roasting cocoa beans on the aroma and phytochemical profile of dark chocolates (70% cocoa) was studied. Three chocolates produced from microwave roasted beans (450 W–55 min, 600 W–35 min, 900 W–20 min) were compared with a chocolate produced from convectively roasted beans (130 °C–30 min). Aroma analysis via HS-SPME-GC-MS indicated that microwave roasting of cocoa beans resulted in chocolate with a distinctive aroma profile, compared to the chocolate produced from convectively roasted beans. Increased power input seems the main inducer of elevated levels of aroma compounds. Interestingly, the impact of the four treatments on the phytochemical profile, measured via LC-HRMS, of the chocolates was rather comparable. Microwave roasting of cocoa beans was more prone to oxidation, but still within acceptable limits. The results validate that microwave roasting is a promising alternative technique that can be used effectively for chocolate production.

Proximal chemical evaluation, antioxidant content and fatty acids in fermented and dried cocoa beans, roasted cocoa beans and cocoa pulp bar (Theobroma cacao L. Criollo cultivar)

Proximal chemical evaluation, antioxidant content and fatty acids in fermented and dried cocoa beans, roasted cocoa beans and cocoa pulp bar (Theobroma cacao L. Criollo cultivar)

Comparison of Thermal Characteristics and Fatty Acids Composition in Raw and Roasted Cocoa Beans from Peru (Criollo) and Ecuador (Forastero)

The aim of this research was to complete the characteristics of cocoa beans and cocoa butter extracted from two different Theobroma cacao species: Criollo originated from Peru and Forastero originated from Ecuador, both in the version of raw (unroasted) and roasted beans. Before extraction, the cocoa beans were characterized by proximate analysis. The determination of fatty acids composition was carried out by gas chromatography (GC). The positional distribution of fatty acids in the sn-2 positions of triacylglycerols (TAGs) was also determined. The thermogravimetric analyses (TGA/DTG) were performed under the nitrogen and oxygen atmosphere of roasted and unroasted cocoa beans. The kinetic information was helpful to assess the oxidative stability of cocoa butter. The cocoa butter extracted from unroasted Forastero from Ecuador had the highest values of oxidation activation energy Ea. The melting characteristics of cocoa butter extracted from roasted Criollo species were very similar to their unroasted versions. The same trend was not observed for Forastero species. TGA and DTG were revealed to be useful tools for the analysis of whole cocoa beans and the fats extracted from these cocoa beans.

Effects of Processing Time and Temperature on Flavanol and Procyanidin, Proanthocyanidin and Antioxidant Activity of Cocoa Bean in Taiwan

Flavanol in cocoa is beneficial to cardiovascular health. This study investigated the effect of roasting conditions, temperature ranging from 110 to 150°C and time duration 15-35 min, on the level of flavanol and procyanidin (FP), total proanthocyanidin (PAC) and antioxidant activity of fermented cocoa beans in Southern Taiwan. The content of FP in unroasted and roasted cocoa bean was determined by the normal phase HPLC method and the antioxidant activity was assayed by DPPH and ABTS methods. High roasting temperature for long time decreased the content of FP and PAC in cocoa beans, where ranged from 55.30±1.95 mg (-)-epicatechin equivalents /g and 103.56±8.33mg procyanidin B1/g (at 110°C for 15 min) to 19.12±0.66 mg (-)-epicatechin equivalents /g and 51.58±0.86 mg procyanidin B1/g (at 150°C for 35 min), respectively. Meanwhile, as the roasting temperature rose, the DPPH and ABTS free radical scavenging ability of roasted cocoa bean extracts decreased gradually, varying from the maximum (IC50 = 104±2 µg/ml and 50.4±1.1mg TE/g) for unroasted bean to the minimum (IC50 = 144±4 µg/ml and 27.7±2.4 mg TE/g), and then slightly increased to IC50=134±4 µg/ml and 31.5±0.7 mg TE/g, respectively at most severe roasting treatment, showing the formation of melanoidins and polyphenols caused the synergistic effect, leading to the rise of the antioxidant activity. The first order kinetic reaction and the Arrhenius equation were applied to forecast the change of FP concentration during roasting. The activation energy of FP degradation is 11.2 kcal/mol. The obtained kinetic equation could be useful to predict the remaining amount of FP in cocoa beans under the designed experiment. The cocoa products with higher flavanol content and antioxidant activity could be possible by setting appropriate roasting conditions.

Cocoa melanoidins reduce the formation of dietary advanced glycation end-products in dairy mimicking system

The control of Maillard reaction in foods is important to preserve protein nutritional quality. In this study, we investigated the effects of melanoidins obtained from different roasted cocoa beans toward the formation of dietary advanced glycation end-products (d-AGEs) in aqueous solution of whey protein (WP) and glucose, glyoxal and methylglyoxal at 35 °C and pH 7.0. Cocoa melanoidins (4 mg/mL) were more effective to inhibit glyoxal-derived d-AGEs than methylglyoxal-derived d-AGEs, with 74.4% and 48% reduction of N-ε-carboxymethyllysine and methylglyoxal-hydroimidazolone formation in WP/glyoxal and WP/methylglyoxal system, respectively. Furthermore, protein-bound N-ε-fructosyllysine, measured through furosine, decreased down to 57.2% in presence of cocoa melanoidins in WP/glucose model system suggesting an effective control of the Maillard reaction in an early stage. These findings highlighted that cocoa melanoidins are functional ingredients able to mitigate protein glycation in dairy products during storage.

The Effects Of Acute Consumption Of A Brewed Cocoa Beverage On Endothelial Function

Previous studies have shown that the polyphenol components of cocoa can improve the health and function of blood vessels. It is currently unknown whether consuming a brewed drink made from roasted cocoa beans has the same beneficial effects on blood vessel function. PURPOSE: The purpose of this study was to assess the acute effects of consuming brewed cocoa on resting blood pressure and endothelial function using near-infrared spectroscopy (NIRS) to evaluate changes in tissue oxygen saturation (StO2) following blood vessel occlusion. METHODS: A total of 15 healthy college-aged adults participated in this study. StO2 levels were monitored continuously throughout the test using a NIRS device placed on the flexor digitorum profundus of the dominant arm. Baseline StO2 levels were measured for 5 minutes following 10 minutes of supine rest, after which blood flow to the forearm was occluded for 3 minutes using a blood pressure cuff inflated to 50mmHg above resting systolic pressure, followed by a 5-minute period of reperfusion following release of the cuff. Subjects then consumed either plain water, or the cocoa treatment (40g of roasted cocoa brewed for 10 minutes), and all testing was repeated 90 minutes later. Subjects returned to the lab on a separate day to repeat the test using the opposite beverage. RESULTS: The change from baseline was not significantly different between water (W) and cocoa (C) for resting heart rate (C= -6.6+6.5 bpm, W= -4.4+7.0 bpm; p=0.29), resting systolic blood pressure (C= 0.9+4.5 mmHg, W= -2.2+7.4 mmHg; p=0.10), resting diastolic blood pressure (C= -1.1+6.7 mmHg, W= 0.8+4.5 mmHg; p=0.39), pre-occlusion StO2 (C= 1.6+5.6 %, W= -1.9+6.9%; p=0.06), minimum StO2 during occlusion (C= -0.6+10.5 %, W= -0.7+12.8%; p=0.98), reperfusion maximum StO2 (C= 0.5+3.6 %, W= -0.8+5.0 %; p=0.40), or reperfusion rate quantified as the slope of the StO2 during the first 10 seconds of reperfusion (C= 0.1+0.4 % s-1, W= 0.06+0.4 % s-1; p=0.79). CONCLUSION: Consumption of a brewed cocoa drink does not significantly affect markers of endothelial function or blood pressure in healthy college-aged adults.

Effects of Raw and Roasted Cocoa Bean Extracts Supplementation on Intestinal Enzyme Activity, Biochemical Parameters, and Antioxidant Status in Rats Fed a High-Fat Diet.

The aim of the study was to analyze the influence of diet containing the polyphenol-rich material on intestinal enzyme activity, oxidative stress markers, lipid metabolism and antioxidant status of laboratory rats. The animals were fed high-fat diet supplemented with freeze-dried water extracts of raw and roasted cocoa beans of Forastero variety. The observed changes indicated the biological activity of polyphenols and other components of the prepared cocoa beans extracts (CBEs). The presence of raw and roasted CBEs in the diets diversified the activity of the enzymes of the cecal microflora of rats. Both CBEs beneficially affect the antioxidant status of the serum, even in relation to the control standard group. The experimental cocoa bean preparations showed no significant effect on the mass of rats’ liver, heart, and kidneys, but varied some parameters of the antioxidant status of their organisms. The raw CBE in rats fed with the high-fat diet shows a high ability to inhibit lipid peroxidation in heart and more effectively increases hepatic reduced glutathione (GSH) concentrations compared to the roasted CBE, which did not show any significant effect. Moreover, supplementation with both CBEs significantly affects the volatile fatty acids concentration in the rats’ cecum. Results of this study contribute to the evidence that dietary supplementation with raw and roasted CBEs can exert health-promoting effects, however further studies are necessary.

Volatile fingerprint of unroasted and roasted cocoa beans (Theobroma cacao L.) from different geographical origins

The aroma characterization of 58 unroasted cocoa beans from 22 different geographical origins was performed by head space solid phase micro-extraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS). Sampling is representative of the average world production (America, Africa, and Southeast Asia). Analysis of cocoa beans before and after roasting were performed to follow the aroma modification with the aim to achieve a cocoa volatile fingerprint and a discrimination model based on beans origin.A total of 57 volatiles was identified in unroasted cocoa beans, while 71 volatiles were identified in roasted cocoa beans. The compounds belong to several chemical groups including esters, alcohols, organic acids, aldehydes, ketones and pyrazines. Datasets were submitted to multivariate statistical analysis (Principal Component Analysis, PCA). Results allowed to discriminate unroasted cocoa beans based on their geographical origin: samples coming from African countries were separated from samples of American regions, whereas samples from Southeast Asia lie between the other two continents suggesting that Asian samples have intermediate characteristics between African and South American cocoa beans. PCA, applied on the corresponding roasted samples, showed that although the same roasting treatment has been applied to all the samples, the differences among the unroasted samples were also maintained in the aromatic profile after roasting.The discrimination model based on volatile fingerprint combined with chemometric tools, showed interesting potential for origin authentication of both unroasted and roasted cocoa beans.

Cocoa beans of different origins and varieties and their derived products contamination with polycyclic aromatic hydrocarbons

Levels of polycyclic aromatic hydrocarbons (PAHs) in cocoa beans of several varieties originating from different countries and their derived products from one technological line were examined. PAHs analysis was performed using HPLC–FLD/DAD and confirmed by GC–MS. Significant differences in total 19 PAHs contents between raw cocoa beans of different varieties and origins were observed. The highest sums of 19 PAHs were determined in roasted cocoa beans, cocoa mass and cocoa butter (16.69–74.15 μg kg−1 of fat). The roasting temperature of 160 °C led to PAHs formation, though not the heavy ones. Lowering temperature to 140 °C while extending the time minimized the total contamination but to a small extent. In all samples relatively low levels of total contamination were noted, with light PAHs being predominant and the sum of 4 heavy and marker PAHs much lower than the maximum legal limit. Therefore, analysed products, especially chocolate, do not threaten consumers’ health.

Water dynamics adsorption properties of dried and roasted cocoa beans (theobroma cacao L.)

ABSTRACT Water adsorption properties are necessary for determining and analyzing water sorption in dried and roasted cocoa beans during storage. Thus, this study aimed to determine the water adsorption isotherms and thermodynamic properties at temperatures of 25, 30, and 40°C and water activities between 0.10 and 0.85 using dynamic dew point method. Thirteen different models were fitted to experimental data to represent the dependence of the equilibrium moisture content. Additionally, the thermodynamic properties were determined using the best-fit isotherm model. The isotherms of dried and roasted cocoa beans showed typical behavior of products rich in soluble components, according to Brunauer-Emmett-Teller (BET) classification, which was satisfactorily modeled using the Iglesias and Chirife and Kuhn equations, respectively. The thermodynamic properties showed that the net isosteric heat of adsorption and the Gibbs free energy decreased with the equilibrium moisture content, indicating the energy changes and spontaneity during the adsorption process. The integral entropy of adsorption indicated the best conditions for product stability during storage.

5-Hydroxymethylfurfural and acrylamide content of cocoa shell treated with high voltage electrical discharge

5-hydroxymethylfurfural (5-HMF) and acrylamide, as products of Maillard's reactions, are present in roasted cocoa shell. Since the cocoa shell is increasingly being researched for use in food enrichment due to high fiber and polyphenols content, it is necessary to solve the problem of components that can be harmful to human health. We evaluated the effect of high voltage electrical discharge (HVED) on colour, moisture, 5-HMF and acrylamide content in cocoa shell obtained after roasting cocoa beans. The effects of concentration, frequency and time of cocoa shell treatment were investigated. HVED proved to be a successful method for reducing the content of acrylamide and 5-HMF. In addition, darkening of samples was observed which could mean that further reactions of those components occurred.

In Vitro Antioxidant Activity and FTIR Characterization of High-Molecular Weight Melanoidin Fractions from Different Types of Cocoa Beans.

Melanoidins from real foods and model systems have received considerable interest due to potential health benefits. However, due to the complexity of these compounds, to date, the exact structure of melanoidins and mechanism involved in their biological activity has not been fully elucidated. Thus, the aim of this study was to investigate the total phenolic content, antioxidant properties, and structural characteristics of high-molecular weight (HMW) melanoidin fractions isolated by dialysis (>12.4 kDa) from raw and roasted cocoa beans of Criollo, Forastero, and Trinitario beans cultivated in various area. In vitro antioxidant properties of all studied HMW cocoa fractions were evaluated by four different assays, namely free radical scavenging activity against DPPH• and ABTS•+ radicals, ferric reducing antioxidant power (FRAP), and metal-chelating ability. Additionally, the structure–activity relationship of isolated HMW melanoidin fractions were analyzed using attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). The results show that roasting at a temperature of 150 °C and a relative air humidity of 0.3% effectively enhances the total phenolics content and the antioxidant potential of almost all HMW cocoa melanoidin fractions. The ATR-FTIR analysis revealed that the various mechanisms of action of HMW melanoidins isolates of different types of cocoa beans related to their structural diversity. Consequently, the results clearly demonstrated that HMW cocoa fractions isolated from cocoa beans (especially those of Criollo variety) roasted at higher temperatures with the lower relative humidity of air possess high antioxidant properties in vitro.

Estimated daily intake and risk of prevailing acrylamide content of alkalized roasted cocoa beans

Abstract The consistency of the brown color, flavor and dispersability of cocoa solids is the goal of a successful Dutching process of cocoa masse. However, acrylamide, a known probable carcinogen which is one of the by-products of browning reactions, is linked to the strength of alkalis used in the Dutching process. This study used Response Surface D-optimal, 20 experimental runs to determine acrylamide content of beans after using treatment factors; temperature (110–160 °C), time (20–50 min) and K2CO3 (10–70% w/v). Subsequently, the alkalized cocoa masses were treated to obtain extracts containing acrylamide using QuEChERS method. The concentrations of the acrylamide were determined using HPLC after which the data was processed by fitting a cubic process order followed by diagnostics to remove outliers. The results yielded optimized process conditions of treatment to yield low acrylamide content, which was later validated to be 7.7 × 10−2 mg/g, at alkali concentration of 29.17% and roasting temperature - time system of 110 °C and 20 min respectively. Though the validated acrylamide content was relatively lower than what has been reported in some European markets, it was found to be still high relative to other markets. This suggest that the application of K2CO3 could hold promise of lowering acrylamide concentrations. However, after exposure studies, the validated acrylamide yielded a probable risk of ‘4 in 1000’ adults and ‘2 in 100’ young children consumers of chocolate products, which were highly unacceptable relative to the deminimis (‘1 in 1,000,000’). Thus, based on the deminimis risk, further control measures must be sought to produce safer alkalized cocoa masse.

Application of an olfactory system to detect and distinguish bitter chocolates with different percentages of cocoa

AbstractChocolate is one of the most consumed products in the world. Chocolate is a mixture of roasted cocoa beans and ultrafine particles of sugar (or without containing cocoa butter). The mixture is supplied with different percentages of cocoa in the market. In this research, the ability of an olfactory system is evaluated as a fast, nondestructive, and low‐cost method to detect bitter chocolates with different cocoa percentages. For this purpose, bitter chocolates with three different percentages of cocoa (78, 85, and 96%) were selected for evaluation. Separation rate of electronic nose (E‐nose) dataset obtained 99%, by using principal components analysis method. To assess the classification accuracy of the bitter chocolate samples, linear discriminant analysis, and support vector machine applied. The results showed that both methods were able to classify bitter chocolates of different percentages of cocoa with the highest accuracy of 100%. This research demonstrates the potential of using the olfactory system as a fast, nondestructive, low‐cost, and reliable method for distinguishing and categorizing different cocoa percentages in bitter chocolates with high precision.Practical applicationsMost researches were focused on a specific percentage of cocoa, while there are few reports on the detection of different percentages of cocoa of the same type. In our study, the linear discriminant analysis and support vector machine methods were employed to the distinguishing of various percentages of cocoa of same type (bitter chocolate), and it was observed that both methods achieved the better classification performance, which indicated the feasibility of distinguishing different percentages by E‐nose. It is well‐known that the detection of different cocoa percentages from the same type would take a long time and require developed instrumental laborites with experts, thus it is of great significance to establish a rapid nondestructive detection method for the related study in the field of the cocoa industry.