Report on the 17th inter-laboratory comparison organised by the European Union Reference Laboratory for Polycyclic Aromatic Hydrocarbons: Four marker PAHs in cocoa products

This report presents the results of the seventeenth inter-laboratory comparison (ILC) organised by the European Union Reference Laboratory for Polycyclic Aromatic Hydrocarbons (EURL PAH) on the determination of the four EU marker PAHs, benz[a]anthracene (BAA), benzo[a]pyrene (BAP), benzo[b]fluoranthene (BBF) and chrysene (CHR) in cocoa products. It was conducted under ISO 17043 accreditation. Both officially nominated National Reference Laboratories (NRLs) and official food control laboratories (OCLs) of the EU Member States were admitted as participants. In agreement with National Reference Laboratories, the test material used in this exercise was milk chocolate and cocoa powder. Participants also received a solution of PAHs in solvent of their choice (either toluene or acetonitrile) with disclosed content for the verification of their instrument calibration. . The participants were free to choose the method of analysis.. Reference values were used to benchmark the results reported by participants. The performance of the participating laboratories in the determination of the target PAHs in smoked meat was expressed by z-scores. Satisfactory performance with regard to z-scores was assigned to about 77% of the reported results.JRC.D.5-Standards for Food Bioscienc

Cocoa polyphenols and inflammatory markers of cardiovascular disease

Epidemiological studies have demonstrated the beneficial effect of plant-derived food intake in reducing the risk of cardiovascular disease (CVD). The potential bioactivity of cocoa and its polyphenolic components in modulating cardiovascular health is now being studied worldwide and continues to grow at a rapid pace. In fact, the high polyphenol content of cocoa is of particular interest from the nutritional and pharmacological viewpoints. Cocoa polyphenols are shown to possess a range of cardiovascular-protective properties, and can play a meaningful role through modulating different inflammatory markers involved in atherosclerosis. Accumulated evidence on related anti-inflammatory effects of cocoa polyphenols is summarized in the present review

Optimization of bitterness in chocolate through roasting with analysis of related changes in important bitter compounds

Chocolate is made from the fermented, dried, and roasted seeds of the Theobroma cacao tree, an important agricultural food crop which contains bioactive flavonoid polyphenols with beneficial health effects. Such effects include improvement of antioxidant status, positive impacts on cardiovascular health and endocrine system function, association with cancer prevention, LDL cholesterol reduction, and reduction of obesity and related conditions. However, products which have the highest levels of cacao flavonoids of all eating-chocolate, such as high-cacao-percentage dark chocolate, are known to be quite bitter, a taste modality that is not readily appreciated by humans. Though the complex causes of bitterness in cacao are still not completely understood, it has long been known that the methylxanthines theobromine and caffeine impart bitterness, as do certain flavan-3-ols, sometimes called catechins, which are a class of the aforementioned healthy bioactive polyphenolic flavonoids, also found in tea. Yet, what else is known of bitterness in cacao is sparse and even contradictory. Work on cacao bitterness has described the importance of cyclic dipeptides called 2,5-diketopiperazines (DKPs), while suggesting some form of interaction between theobromine and DKPs as well. Yet these earlier assertions have only been confirmed with mixed results by others, in part due to the incredible complexity of bitterness in roasted cacao, which has been said to require further sensory evaluation. More recent work on bitterness in cacao suggested for the first time that a DKP called cyclo(Pro-Val) is the most important bitter compound. However, even while seeming to confirm the importance of previously known important bitter compound classes, this research was based upon only a single cacao sample from a single origin of cacao, and with an undefined roasting treatment, even though previous work had noted that differences in DKP formation are dependent upon roast profile. Additionally, sensory work was based in part on recombinants of bitter compounds in aqueous solution, allowing for potentially biased estimation of the contribution of the different compounds to finished chocolate bitterness, since the varying kinetics of dissolution of the diverse bitter compounds from low-moisture, high-fat cacao matrix into saliva were not considered, nor were interactions with aroma compounds present in chocolate. Therefore, much was still to be learned about the variation in bitter-compound composition in cacao and related sensory characteristics, within and between different cacao origins and across different roast profiles. This fact, combined with a growing desire for healthy, functional versions of foods such as chocolate makes research into the impact of cacao roasting on consumer perceptions of bitterness and overall liking in chocolate, and the underlying chemical changes, all the more timely. This research project has resulted in findings covering a significant range of chocolate topics. First of all, a new efficient method for extraction and analysis of important bitter compounds in cacao and chocolate was developed. A custom response-surface methodology (RSM)-based design for the roasting treatments, with emphasis on I-optimality for minimizing prediction variance,was created. Chemical and sensory analysis of the roasted chocolate treatments were carried out, followed by in-depth data analysis and interpretation in the context of current chocolate science. Specifically, the aqueous 70% N,N-Dimethylformamide solvent system and HPLC method developed for fast and efficient extraction, followed by analysis, of important bitter compounds from three different chemical classes (i.e., methylxanthines, flavan-3-ols, and 2,5-diketopiperazines) simultaneously, functioned successfully, resulting in acceptable standard curves,% RSD values, and% recovery values. As for quantitative chemical findings, our work generally supports previous studies as regards changes in chemical concentrations during roasting. However, even with the large number of roasting treatments (i.e. 24, or 8 for each of 3 origins) across a reasonably large experimental region, we did not confirm the presence of concentrations of cyclo(Pro-Val) similar to that of previous research. As for sensory evaluation findings, we discovered that reduction of bitterness, sourness, and astringency are all correlated with increased liking in our chocolates. We also noted that consumers appear to have a preference for increased cocoa intensity. Roast profiles that minimize and maximize these characteristics respectively can vary by origin, but temperature and time combinations such as 20 minutes/171[degrees]C, 80 minutes/135[degrees]C, and 54 minutes/151[degrees]C were generally effective, whereas, raw and lightly roasted treatments (i.e., 0 minutes at 24[degrees]C, 11 minutes at 105[degrees]C, or 55 minutes at 64[degrees]C) were not, resulting in the lowest liking ratings. As with any complex food system, caveats do exist. Additions of sugar, salt, and other ingredients would likely introduce significant effects relevant to overall sensory characteristics and consumer liking, and intensity of various other aroma profiles not yet analyzed could do the same (e.g., floral, fruity, nutty). One additional sensory finding is that we can now say that perception of chocolate aroma is likely to play a large role in the perception of taste modalities (i.e., bitterness, sourness, sweetness), and astringency, as well as liking in chocolate. Finally, regarding the relationship of bitter chemical concentrations in the treatments, and consumer bitterness perception thereof, while the analysis is somewhat complicated by the stability of theobromine and caffeine during roasting, we can say that we have little evidence to suggest that theobromine concentration is strongly correlated to bitterness in chocolate. There is far more evidence that caffeine may play a role in the increase of bitterness in cacao, though the magnitude of its importance is not yet known, and to better understand the impact of both theobromine and caffeine, study of many more origins will be required. As for epicatechin and procyanidin B2, as already known, they are quite well correlated, and of all the chemicals we studied, they were, as a pair, the most correlated with changes in bitterness in our data across all treatments, including all three origins. Given that epicatechin has previously been shown to be a more important contributor to bitterness than higher molecular weight procyanidins (e.g., procyanidin B2), the overall importance of epicatechin could be the greatest of all the compounds that we studied. In contrast, catechin and cyclo(Pro-Val), do not appear to be particularly important for changes in bitterness. More specifically, we have found no evidence supporting the claim that the DKP cyclo(Pro-Val) is the most important bitter compound in cacao or chocolate. This does raise additional questions about the importance of diketopiperazines (DKPs) as a class as they relate to bitterness in chocolate.Includes bibliographical references (pages 353-374)

Expression of multidisciplinary flavour science : proceedings of the 12th Weurman Symposium

The 12th Weurman Flavour Research Symposium contributed 177 lectures and posters to the wealth of flavor knowledge; these were presented in eight sessions: biology, retention and release, psychophysics, quality, thermal generation, bioflavors, impact molecules, and analytics. Emerging topics were discussed in three workshops dealing with flavor and health, in vivo flavor research, and flavor metabolomics. It has been an excellent forum for passionate exchange of recent results obtained in traditional and emerging fields of flavor research. The symposium allowed coverage of the broad diversity of flavor-related topics: comprising odor and taste; applying targeted and holistic approaches; using sensorial, chemical, biological, physical, and chemometric techniques; as well as considering nutrition and health aspects

A New Age for Quercus spp. Fruits: Review on Nutritional and Phytochemical Composition and Related Biological Activities of Acorns

The current global food system must adapt to the expected growth of world population (about 9 billion individuals by 2050). This adaptation will probably include an increased consumption of edible wild foods, due to their richness in micronutrients and bioactive compounds, besides providing a cost-effective and sustainable way of improving caloric food security. A striking example of such natural matrices is the Quercus genus, which has the additional advantage of being widespread throughout the Northern Hemisphere. In a traditional sense, Quercus fruits (acorns) were mainly used in animal feeding, despite their potentially important role on the rural economy. But this preconception is changing. In fact, their nutritional value, high contents in phytochemical compounds, biological activity (such as antioxidant, anticarcinogenic, and cardioprotective properties) and use in the treatment of specific diseases (such as atherosclerosis, diabetes, or Alzheimer's disease) have raised the interest in integrating acorns into the human diet. Accordingly, this comprehensive overview was designed to provide an evidence-based review of the literature, with the objective to achieve useful conclusions regarding the nutritional properties, methodologies of extraction, identification, and characterization of a wide variety of bioactive compounds and scientifically validated bioactivities in Quercus species worldwide. The industrial by-products from acorn oil extraction or flour production are also included. Data regarding the analytical techniques, individual compounds, and their bioactivities, are organized in tables. The reported data are discussed and directions for further investigations are suggested, highlighting the use of acorns in food, nutraceutical, and pharmaceutical applications.The authors are grateful for the financial support (UID/QUI/ 50006/2013-POCI/01/0145/FEDER/007265) from FCT/ MEC through national funds and cofinanced by FEDER, under the Partnership Agreement PT2020. J.C.M. Barreira thanks FCT, POPH-QREN, and FSE for his grant (SFRH/BPD/72802/ 2010). The authors thank Telma Oliveira for drawing the acorn sketch depicted in Figure 1.info:eu-repo/semantics/publishedVersio

Expression of multidisciplinary flavour science : proceedings of the 12th Weurman Symposium

The 12th Weurman Flavour Research Symposium contributed 177 lectures and posters to the wealth of flavor knowledge; these were presented in eight sessions: biology, retention and release, psychophysics, quality, thermal generation, bioflavors, impact molecules, and analytics. Emerging topics were discussed in three workshops dealing with flavor and health, in vivo flavor research, and flavor metabolomics. It has been an excellent forum for passionate exchange of recent results obtained in traditional and emerging fields of flavor research. The symposium allowed coverage of the broad diversity of flavor-related topics: comprising odor and taste; applying targeted and holistic approaches; using sensorial, chemical, biological, physical, and chemometric techniques; as well as considering nutrition and health aspects

α-Dicarbonyl compounds trapping ability and antiglycative effect of high-molecular-weight brewer's spent grain melanoidins

Polyphenols participate in the Maillard reaction pathways scavenging α-dicarbonyl compounds (DCs) and contributing to the mitigation of carbonyl burden through dietary exposure/routes. The current study demonstrated the effectiveness of high-molecular-weight brewer's spent grain melanoidins (HMW-BSGM) in reacting with DCs in an in vitro model system. HMW-BSGM (4 mg/mL) quenched more than 95% of glyoxal and methylglyoxal, and more than 80% of 2,3-butanedione after a 7-day incubation at 37 °C. Among tested polyphenols, sinapic acid showed the highest trapping capacity with inhibition rates of 33.1, 49.1 and 49.3% for glyoxal, methylglyoxal and 2,3-butanedione because of hydroxyalkylation reaction as revealed by liquid chromatography high-resolution tandem mass spectrometry experiments. The formation of free fluorescent AGEs was substantially hindered (79.3%) by HMW-BSGM (4 mg/mL). These findings corroborate the hypothesis that the accumulation of polyphenols in melanoidins skeleton can hinder undesired effects and potentially harmful reactions involving α-dicarbonyl compounds