Antioxidant Activity and Multi-Elemental Analysis of Dark Chocolate

Leveraging infrared spectroscopy for cocoa content prediction: A dual approach with Kohonen neural network and multivariate modeling

People of all ages enjoy chocolate, and its popularity is attributed to its pleasant taste and aroma, as well as its associated health benefits. Produced through both artisanal and industrial processes, which involve harvesting, selecting, fermenting, roasting and grinding cocoa beans, chocolate has a diverse chemical composition. It contains stimulants for the central nervous system, including caffeine and theobromine, and antioxidants and flavonoids, some of which are associated with promoting cardiovascular health, circulatory function, alertness, and attention. This study aimed to use NIR spectroscopy to determine whether this technique can effectively quantify the percentage of cocoa present in commercial chocolates. In the exploratory analysis of the NIR spectra, conducted in the range of 900-1600 nm, it was observed that the cocoa percentage in the samples correlated most strongly with chemical groups exhibiting absorbance in the range of 900-1400 nm. Principal Component Analysis (PCA) exhibited good discriminatory ability between samples with different cocoa percentages. Kohonen neural networks have also been proven effective in processing high-dimensional nonlinear data and complementing PCA analysis in pattern recognition. Additionally, Principal Component Regression (PCR) was performed to evaluate the predictive capability of cocoa percentage based on NIR spectra, yielding an R2 value of 0.84. The study demonstrates that integrating the NIR spectra with PCA/PCR and KNN enables cocoa percentage identification, making it a valuable tool for chocolate quality control and authenticity assurance.

Impact of Chocolate Cadmium on Vulnerable Populations in Serbia

Chocolate is one of the most popular and widely consumed confectionery products. However, elevated cadmium (Cd) content in this commodity threatens food safety and human health. It is crucial to monitor the presence of Cd in chocolate and to evaluate its associated health risks. This study assessed the Cd levels in milk and dark chocolates from the Serbian market (n = 155). Cadmium concentrations varied between 0.010 and 0.29 mg/kg. The obtained values were used to evaluate the hazard quotient (HQ) and cancer risk (CR). The estimated weekly intakes (EWIs) were below the tolerable limits for all samples. However, in some samples, the EWI reached 60.9% and 63.5% of the tolerable limit for toddlers and other children, respectively. No health risk was found based on the HQ. On the other hand, based on CR values, all chocolate products can be classified as posing a moderate risk. The Monte Carlo simulation indicated that toddlers and other children were more exposed to non-carcinogenic risk, whereas vegetarians, adults, pregnant women, and other children were more exposed to cancer risk. Sensitivity analysis indicates that body weight, exposure frequency, and ingestion rate are the most influential factors for non-cancer and cancer health risks.

Characterization of dark chocolates based on polyphenolic profiles and antioxidant activity

Dark chocolates were characterized according to geographical origin, cocoa variety, and cocoa content using the methylxanthine and polyphenolic composition and antioxidant activity as the data. The main study objective was to uncover sample patterns and identify possible markers of quality, variety, or origin to deal with authentication or fraud detection issues. In the study, a set of 26 dark chocolates from different varieties (e.g., Criollo, Forastero, and Trinitario) harvested in Africa, America, and Asia was analyzed. The optimized sample treatment consisted of defatting the chocolate (1 g of sample with 5 mL of cyclohexane for 15 min, three times) and then extracting the analytes by sonication with methanol/water 60:40 (v:v) for 15 min. The filtered extracts were analyzed by reversed-phase high-performance liquid chromatography with UV and spectrophotometric methods (Folin-Ciocalteu, ferric reducing antioxidant power, and aluminum methods) to determine individual phenolics and overall indexes of antioxidant and flavonoid content. Results from this chocolate set indicated that American samples are richer than African counterparts in alkaloids and phenolics (e.g., 1.7 vs. 1.1 mg g-1 caffeine and 14.5 vs. 12.5 mg g-1 total flavanols, respectively). Regarding cocoa varieties, Criollo cocoa was richer in bioactive compounds and antioxidant capacity (e.g., 16, 15, and 12 mg g-1 total flavanols for Criollo, Forastero, and Trinitario, respectively). These results indicate that the analytes resulted in potential descriptors of varietal or geographical attributes.

Chocolate microstructure: A comprehensive review

Chocolate is a food with complex microstructure properties. In this study, chocolate surface and internal microstructures are discussed considering final product quality and stability. In addition, the effects of the solids and continuous phase components and the interactions between them, and also process effects on the microstructure were reviewed. Irregularities in the internal microstructure affect the surface and cause problems such as unstable cocoa butter crystals, a whitish, streaky appearance, chewy especially fat bloom in this layer and in general, a low quality and sensory in final product. Optimization of the particle size and cooling conditions of the solids is required to modify the surface topography for roughness and pores morphology. Reducing surface porosity can increase fat bloom resistance. For this purpose, reducing surface hydrophobicity by considering proteins with di-sulfide bonds and their concentrations and the use of different bulk sweeteners should be taken into consideration. The morphology of the surface microstructure may be used for product characterization as well as to investigate the environmental conditions exposed during processing and storage. It should be noted that chocolate has a three-phase microstructural system, considering the air present in the gaps at the interface. The importance of the third phase for continuous phase mobility is critical. Additionally, this phase affects behavior in the oral cavity due to melting and release of volatile components.

A clinical trial of the effects of cocoa rich chocolate on depression and sleep quality in menopausal women

In this triple-blind, randomized clinical trial, 60 menopausal women between the ages of 45 and 65 were randomized to receive 78% dark chocolate (12 g/day) or milk chocolate (12 g/day) for eight weeks. The primary outcome was depression scores. Secondary outcomes included sleep quality and anthropometric indices. ANCOVA with baseline adjustment showed that the mean depression score after the intervention in the group receiving dark chocolate was significantly reduced compared to the milk chocolate group (mean difference: -2.3; 95% confidence interval: -3.9 to -0.8; p = 0.003; Cohen's d = -0.54). However, no statistically significant difference in the overall sleep quality score and its subdomains was observed between the two groups after the intervention (p > 0.05). Furthermore, after the intervention, there was no statistically significant difference between the two groups in terms of anthropometric indices, including weight (p = 0.075), BMI (p = 0.137), waist circumference (p = 0.463), and hip circumference (p = 0.114). The study suggests that consuming 78% dark chocolate for eight weeks may contribute to improvements in depression scores, but it does not appear to improve sleep quality or anthropometric indices.Trial registration: IRCT20220926056046N1; December 2022.

Development of Novel Honey- and Oat-Based Cocoa Beverages-A Comprehensive Analysis of the Impact of Drying Temperature and Mixture Composition on Physical, Chemical and Sensory Properties

This research aimed to assess the influence of drying temperature (50, 60 and 70 °C), honey/oat flour ratio (60:40, 50:50 and 40:60) and cocoa contents (5, 6.25 and 7.5 g/100 g) on the physical (color, moisture content, bulk density, flowability (Hausner ratio, Carr index), dispersibility, solubility, and particle size), chemical (total dissolved solids, conductivity, pH, amount of sugar, color, total polyphenolic content, and antioxidant activity), and sensory properties (powder appearance, color, odor; and beverage appearance, color, odor, sweetness, bitterness, taste, texture) of a newly developed cocoa powder mixture in which honey was used as a sweetener and oat flour as a filler. Also, a further aim of this study was to optimize the composition of the mixture based on chemical, physical and sensory properties. Based on the optimization results, the highest total polyphenolic content and antioxidant activity were achieved at 70 °C with a honey/oat ratio of 50% and a cocoa content of 7.5 g. Drying temperature has a significant effect on powder odor and beverage odor, as well as on beverage bitterness, while the honey/oat flour ratio has a significant effect on color, with primarily values L* and a*. The cocoa contents mostly affect total polyphenolic content and antioxidant activity.

Enrichment of White Chocolate with Microencapsulated β-Carotene: Impact on Quality Characteristics and β-Carotene Stability during Storage

This study developed functional white chocolate enriched with free (WC-F) and encapsulated β-carotene using whey protein isolate (WPI) and pullulan (PUL) blends through spray drying (WC-SP), freeze drying (WC-LP), and coaxial electrospinning (WC-EL). The thermal properties, rheological properties, hardness, and color of the chocolates were evaluated, and the stability of β-carotene was monitored over 4 months at 25 °C. No significant differences were found in melting profile temperatures among samples; however, WC-LP and WC-EL exhibited higher melting energies (30.88 J/g and 16.00 J/g) compared to the control (12.42 J/g). WC-F and WC-SP showed rheological behaviors similar to those of the control, while WC-LP and WC-EL displayed altered flow characteristics. Hardness was unaffected in WC-F and WC-SP (7.77 N/mm2 and 9.36 N/mm2), increased slightly in WC-LP (10.28 N/mm2), and decreased significantly in WC-EL (5.89 N/mm2). Over storage, melting point, rheological parameters, and hardness increased slightly, while color parameters decreased. β-carotene degradation followed a first-order reaction model, with degradation rate constants (k) of 0.0066 day-1 for WC-SP, 0.0094 day-1 for WC-LP, and 0.0080 day-1 for WC-EL, compared to 0.0164 day-1 for WC-F. WC-SP provided the best β-carotene retention, extending the half-life period by 2 times compared to WC-F (126.04 days vs. 61.95 days). Practical implications: The findings suggest that WC-SP, with its superior β-carotene stability, is particularly suitable for the development of functional confectionery products with extended shelf life, offering potential benefits in industrial applications where product stability is crucial. Future research directions: Further studies could explore the incorporation of additional bioactive compounds in white chocolate using similar encapsulation methods, as well as consumer acceptance and sensory evaluation of these enriched products.

A new method based on extraction induced by emulsion breaking for determination of Co and Ni in chocolate bars by graphite furnace atomic absorption spectrometry

This paper describes a new experimental configuration of extraction induced by emulsion breaking method to extract and determine Ni and Co in chocolate bars by graphite furnace atomic absorption spectrometry. At optimized conditions, the sample (0.08 g) was mixed with 4 mL of extractant solution (4% m/v Triton X-100 and 10% v/v HNO3) in a plastic syringe to form a solid-oil-water emulsion. Then, emulsion breaking was assisted by membrane filtration. The total extraction procedure took approximately 1 min, in opposition to 25 (centrifugation) and 50 min (heating). Extraction yields ranged from 94.8 to 114.3% for Co and from 85.9 to 108.4% for Ni. The limits of detection and quantification were, respectively, 24.73 and 82.45 μg Kg-1 for Co and 49.05 and 163.5 μg Kg-1 for Ni. Recoveries ranged from 92.1 (Ni) to 105.4% (Co).

Recent Advances in the Determination of Major and Trace Elements in Plants Using Inductively Coupled Plasma Optical Emission Spectrometry

Interest in measuring major and trace elements in plants has increased in recent years because of growing concerns about the elements' contribution to daily intakes or the health risks posed by ingesting vegetables contaminated by potentially toxic elements. The recent advances in using inductively coupled plasma atomic emission spectrometry (ICP-OES) to measure major and trace elements in plant samples are reviewed in the present work. The sample preparation before instrumental determination and the main advantages and limitations of ICP-OES are described. New trends in element extraction in liquid solutions using fewer toxic solvents and microextractions are observed in recently published literature. Even though ICP-OES is a well-established and routine technique, recent innovations to increase its performance have been found. Validated methods are needed to ensure the obtaining of reliable results. Much research has focused on assessing principal figures of merit, such as limits of detection, quantification, selectivity, working ranges, precision in terms of repeatability and reproducibility, and accuracy through spiked samples or certified reference materials analysis. According to the published literature, the ICP-OES technique, 50 years after the release of the first commercially available equipment, remains a powerful and highly recommended tool for element determination on a wide range of concentrations.

Modulation of Oxidative Stress and Glycemic Control in Diabetic Wistar Rats: The Therapeutic Potential of Theobroma cacao and Camellia sinensis Diets

  Background Diabetes mellitus is a complex metabolic disorder characterized by oxidative stress and impaired glycemic control. This study investigates the therapeutic potential of Theobroma cacao and Camellia sinensis diets in diabetic Wistar rats and assesses their impact on oxidative stress markers and blood glucose levels. Methods  In this experiment, eight groups of six male Wistar rats (n = 12.5%), aged 8 to 12 weeks, were carefully set up to see how different treatments for diabetes and oxidative stress affected the two conditions. The random selection process was implemented to minimize any potential bias and ensure that the results of the study would be representative of the general population of Wistar rats. The groups were as follows: a nondiabetic control group (NDC) served as the baseline, while diabetes was induced in the alloxan monohydrate group (150 mg/kg). Another group was given the standard drug metformin (M, 100 mg/kg), and two control groups that did not have diabetes were given extracts of Theobroma cacao (TC, 340 mg/kg) and Camellia sinensis (CS, 200 mg/kg). Three groups of diabetic rats were given a mix of these treatments. Theobroma cacao and Camellia sinensis extracts were given at set doses (TC, 340 mg/kg; CS, 200 mg/kg), along with 150 mg/kg of a drug that causes diabetes. Over a 21-day period, oxidative stress parameters such as glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione reductase (GSHrd) levels, and blood glucose were carefully measured to check for signs of oxidative stress and diabetes progression Results Considerable differences in GSH levels were noted across the groups, with the highest GSH concentration found in the group treated with the inducing drug, while the lowest GSH levels were observed in the diabetic group that was administered both Theobroma cacao and Camellia sinensis (p < 0.001). MDA levels also varied, with the diabetic group treated with Theobroma cacao having the highest MDA concentration (3.54 ± 0.29 μmol/L) and the nondiabetic control group treated with Camellia sinensis exhibiting the lowest MDA levels (1.66 ± 0.08 μmol/L; p < 0.001). SOD activity was highest in the standard drug group and lowest in the diabetic group treated with Theobroma cacao. GSH activity was notably higher in the diabetic groups that received dietary interventions (p < 0.001). Blood glucose levels showed diverse responses, with the standard drug group experiencing a substantial reduction, while the inducing drug group exhibited a consistent increase. Conclusion The study highlights the significant impact of dietary interventions with Theobroma cacao and Camellia sinensis on oxidative stress markers and blood glucose regulation in diabetic Wistar rats. These findings suggest a potential role for these dietary components in mitigating oxidative stress and improving glycemic control in diabetes, although further research is warranted to elucidate the underlying mechanisms and clinical implications.

Conching process time, sauco by-product concentration, and sacha inchi oil levels identification for the enrichment of dark chocolate

Chocolate is a widely consumed product with high levels of polyphenols; unfortunately, it is reduced during the process. Adding other components allows for counteracting the polyphenols lost during chocolate processing and reducing the content of unsaturated fatty acids, affecting its physical properties. This study identified the conching time, concentration of sauco by-products, and levels of sacha inchi oil to produce enriched dark chocolates. For this study, sauco by-products in percentages of 2, 6 and 10%, sacha inchi oil in levels of 1, 3, and 5%, and three conching times of 16, 20, and 24 h were added to 75% dark chocolates, and the process conditions were optimized through the response surface methodology (RSM). The physicochemical properties of the dark chocolates were studied, observing that the sauco by-product, sacha inchi oil, and conching time significantly affected (p < 0.05) the variables of antioxidant activity, total phenol content, rheology, hardness, and particle size. The R2 correlation of the factors declared against the variables indicated the model's reliability as it was close to 1. The results suggest that incorporating sauco by-products allows for obtaining chocolates with good chemical properties; however, high percentages of sacha inchi oil and shorter conching time cause a negative effect on the chocolate affecting the physical properties.

Current Understanding of Flavonoids in Cancer Therapy and Prevention

Cancer is a major cause of death worldwide, with multiple pathophysiological manifestations. In particular, genetic abnormalities, inflammation, bad eating habits, radiation exposure, work stress, and toxin consumption have been linked to cancer disease development and progression. Recently, natural bioactive chemicals known as polyphenols found in plants were shown to have anticancer capabilities, destroying altered or malignant cells without harming normal cells. Flavonoids have demonstrated antioxidant, antiviral, anticancer, and anti-inflammatory effects. Flavonoid type, bioavailability, and possible method of action determine these biological actions. These low-cost pharmaceutical components have significant biological activities and are beneficial for several chronic disorders, including cancer. Recent research has focused primarily on isolating, synthesizing, and studying the effects of flavonoids on human health. Here we have attempted to summarize our current knowledge of flavonoids, focusing on their mode of action to better understand their effects on cancer.

Application of HPP for the Development of a Dessert Elaborated with Casein and Cocoa for a Dysphagia Diet

In this study, the application of high-pressure processing (HPP) for optimizing the texture of a cocoa dessert rich in casein and developed for people with dysphagia was investigated. Different treatments (250 MPa/15 min; 600 MPa/5 min) and protein concentrations (10-15%) were combined and evaluated for choosing the optimum combination leading to an adequate texture. The selected formulation was a dessert containing 4% cocoa and 10% casein and subjected to 600 MPa for 5 min. It showed a high nutritional value (11.5% protein) and high antioxidant capacity, which was slightly affected by the HPP processing. The rheological and textural properties showed that HPP had a clear effect on the dessert structure. The loss tangent decreased from 2.692 to 0.165, indicating the transition from a liquid to a gel-like structure, which is in a suitable range for dysphagia foods. During storage (14 and 28 days at 4 °C), progressive significant changes in the structure of the dessert were observed. A decrease in all rheological and textural parameters occurred, except for the loss of tangent, which increased its value. In any case, at 28 days of storage, samples maintained the weak gel-like structure (0.686 loss tangent) that is acceptable for dysphagia management.

Effect of Beetroot Powder Incorporation on Functional Properties and Shelf Life of Biscuits

The demand for ready-to-use functional foods is high, which encourages manufacturers to develop new, nutritionally valuable products. As an excellent source of biologically active compounds, beetroot (Beta vulgaris L.) is considered to have highly beneficial effects on health. This research aimed to evaluate the impact of replacing spelt flour (SF) with 15%, 20% and 25% beetroot powder (BP). The physicochemical and functional properties of biscuits baked at different temperatures (150 and 170 °C) were followed at the beginning, and after 3 and 6 months of storage as standard conditions. Moisture content and water activity (aw) gave insight into the biscuits' shelf life. The value of aw from 0.35 to 0.56 indicated appropriate storability. Dietary fiber content in fresh biscuits ranged from 6.1% to 7.6%, protein from 9.2% to 8.9% and sugar from 30.6% to 35.9%. The content of betalain, total polyphenols and flavonoids, and antioxidant activity (DPPH, FRAP) increased with beetroot powder content incorporated. A slight decrease of all the mentioned parameters during the storage indicated satisfied retention of bioactive molecules. The content of prevalent phenolic compounds gallic and protocatechuic acid, identified by HPLC, decreased from 22.2-32.0 and 21.1-24.9 in fresh biscuits to 18.3-23.4 and 17.3-20.3 mg/100 g upon six months of storage, respectively. An increase of the L* and a* and a decrease of the b* coordinate values, compared with the control sample without beetroot values, was noticed as well as the expected level of their change during the storage. The obtained results indicated that biscuits enriched with beetroot powder showed a significantly improved functional, nutritional and antioxidant potential during storage.

Flavanol-Rich Cocoa Supplementation Inhibits Mitochondrial Biogenesis Triggered by Exercise

The potential role of cocoa supplementation in an exercise context remains unclear. We describe the effects of flavanol-rich cocoa supplementation during training on exercise performance and mitochondrial biogenesis. Forty-two male endurance athletes at the beginning of the training season received either 5 g of cocoa (425 mg of flavanols) or maltodextrin (control) daily for 10 weeks. Two different doses of cocoa (equivalent to 5 g and 15 g per day of cocoa for a 70 kg person) were tested in a mouse exercise training study. In the athletes, while both groups had improved exercise performance, the maximal aerobic speed increased only in the control group. A mitochondrial DNA analysis revealed that the control group responded to training by increasing the mitochondrial load whereas the cocoa group showed no increase. Oxidative stress was lower in the cocoa group than in the control group, together with lower interleukin-6 levels. In the muscle of mice receiving cocoa, we corroborated an inhibition of mitochondrial biogenesis, which might be mediated by the decrease in the expression of nuclear factor erythroid-2-related factor 2. Our study shows that supplementation with flavanol-rich cocoa during the training period inhibits mitochondrial biogenesis adaptation through the inhibition of reactive oxygen species generation without impacting exercise performance.