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BACKGROUND: Coffee roasting is one of the crucial steps in obtaining a high‐quality product as it forms the product's color and flavor characteristics. Roast control is made by visual inspection or traditional instruments such as the Agtron spectrophotometer, which can have high implementation costs. Therefore, the present study evaluated colorimetric approaches (a bench colorimeter, smartphone digital images, and a colorimetric sensor) to predict the Agtron roasting degrees of whole and ground coffee. Two calibration approaches were assessed, that is, multiple linear regression and least‐squares support vector machine. For that, 70 samples of whole and ground roasted coffees comprising the Agtron roasting range were prepared. RESULTS: The results showed that all three colorimetric acquisition types were efficient for the model building, but the bench colorimeter and the smartphone digital images generally performed with good determination coefficients and low errors as measured by external validation. For the whole bean coffee, the best model presented a determination coefficient (R2) of 0.99 and a root‐mean‐squared error (RMSE) of 1.91%, while R2 of 0.99 and RMSE of 0.87% was obtained for ground coffee, both using the colorimeter. CONCLUSION: The obtained models presented good prediction capability, as assessed by external validation and randomization tests. The obtained findings point to an alternative for coffee roasting monitoring that can lead to higher digitalization and local control of the process, even for smaller producers, due to its lower costs. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Magnetization reduction roasting is an important method for the utilization of oolitic magnetite. In this study, the magnetization reduction behavior and kinetics of oolitic hematite in gas-based roasting were systematically investigated by X-ray photoelectron spectroscopy (XPS). The results revealed that under optimal roasting conditions of 650 °C, a roasting time of 60 min, and a CO concentration of 30%, the magnetization reduction rate of the roasted product reached 44.34%. Furthermore, the weak magnetic separation concentrate presented a TFe of 58.09% and a concentrate iron recovery of 94.3%. The results of the XPS spectrum indicated that the peak area ratio (Fe2+/Fe3+) gradually increased with an increase in roasting temperature, roasting time, and CO concentration, while over-reduction occurred when the roasting temperature exceeded 750 °C. The investigation of magnetization roasting kinetics for varying particle sizes demonstrated that the magnetization reduction process is controlled by chemical reaction, with a corresponding activation energy range of 42.96 kJ/mol to 63.29 kJ/mol, indicating the particle size has little effect on the magnetization reduction of oolitic hematite. [ABSTRACT FROM AUTHOR]

Background Food allergen cross-contact during food preparation and production is one of the causes of unintentional allergen presence in packaged foods. However, little is known about allergen cross-contact in shared frying or roasting oil, which prevents the establishment of effective allergen controls and may put allergic individuals at risk. To better understand the quantity of allergen transferred to frying oil and subsequent products, an analytical method is needed for quantifying protein in oil that has been exposed to frying/roasting conditions. Objective The goal of this study was to develop a parallel reaction monitoring LC–MS/MS method to quantify the amount of cashew protein in shared roasting oil. Methods The sample preparation method was evaluated to improve protein extractability and peptide performance. Four quantitative peptides representing cashew 2S and 11S proteins were selected as targets based on their sensitivity, heat stability, and specificity. A calibration strategy was developed to quantify the amount of total cashew protein in oil. Method performance was evaluated using a heated cashew-in-oil model system. Results The method showed high recovery in oil samples spiked with 100 or 10 parts per million (ppm) total cashew protein heated at 138 or 166°C for 2–30 min. Samples (100 ppm total cashew protein) heated for 30 min had more than 90% recovery when treated at 138°C and more than 50% when heated at 166°C. Conclusion The method is fit-for-purpose for the analysis of cashew allergen cross-contact in oil. Highlights A novel MS-based method was developed that can accurately quantify the amount of cashew protein present in heated oil. [ABSTRACT FROM AUTHOR]

Coffee is one of the most consumed products worldwide. Among the varieties of this product, specialty coffee is a type of coffee that has been growing in the world market. This paper aims to assess the effects that the conditions derived from coffee roasting at different altitude levels have on the quality of the product. It was discovered that processing coffee at a higher altitude level yielded a smaller increase in bitterness. This led to a better Specialty Coffee Association (SCA) score in cupping and, consequently, to better preservation of the coffee quality. The storage time affected the aroma by associating roaster aromas with older coffees. Although the assessed origins had the same NIR spectra, differences in peak intensity lead to variations in the flavor and aroma of the coffee. Furthermore, although green beans prolong quality allowing a SCA score of 84.73 ± 2.81 after 4 months of storage, roasted coffee at higher altitudes could also maintain the quality between production and consumption (SCA score of 80.22 ± 0.91 after 2 months). Finally, this research found that the instrumental equipment helped to find minor changes in the sensorial profile, and with these changes correlated with the sensorial panel, the best conditions to preserve coffee quality were found. [ABSTRACT FROM AUTHOR]

Roasting is an important step in the pretreatment of biomass upgrading. Roasting can improve the fuel quality of biomass, reduce the O/C and H/C ratios in the biomass, and provide the biomass with a fuel quality comparable to that of lignite. Therefore, studying the structure and component evolution laws during biomass roasting treatment is important for the rational and efficient utilization of biomass. When the roasting temperature is 200–300 °C, the cellulose and hemicellulose in the biomass undergo a depolymerization reaction, releasing many monocyclic aromatic hydrocarbons with high reactivity. The proportion of monocyclic aromatic hydrocarbons in biomass roasting products can be effectively regulated by controlling the reaction temperature, residence time, catalyst, baking atmosphere, and other factors in the biomass roasting process. This paper focuses on the dissociation law of organic components in the pretreatment process of biomass roasting. [ABSTRACT FROM AUTHOR]

In the present study, three degrees of roasting (light, medium, and dark), which significantly differentiate the properties of coffee beans, were analyzed. Additionally, the effect of the roasting level on the profile of volatile and biologically active compounds, including chlorogenic acids, tocopherols, and caffeine, was determined. Light-roast coffee beans, referred to as the Cinnamon roast, were obtained at 198℃. In turn, American roast beans were obtained at 212℃ before the second crack, and dark beans classified as the Italian roast were obtained in a roasting process carried out at 228-230℃. The content of bioactive compounds in green coffee beans was determined as well. The 'Typica' cultivar of Arabica coffee originating from a plantation located at an altitude of 1680 m a.s.l. in Huehuetenango Department, Guatemala, was used in the study. The analyses showed that the different parameters of coffee bean roasting (Cinnamon, American, and Italian roast) resulted in differences in the levels of phenolic compounds, caffeine, and tocopherols. The American roast style was shown to be the most balanced type of roasting in terms of the content of bioactive compounds as well as the chemical groups and profile of volatile compounds. This roasting type also exhibited the highest intensity of emission of volatile compounds, which is expected by the consumer. The study also demonstrated that the coffee bean roasting process generated different levels of phenolic compounds, caffeine, and tocopherols. [ABSTRACT FROM AUTHOR]

Bell peppers (Capsicum annuum L.) in various stages of maturity are widely used in the diets of individuals and in the food industry; they are consumed both fresh and after thermal processing. However, every type of processing impacts the overall textural and bioactive characteristics of this plant-based food. In order to quantify the changes in the bioactive substances and color-structural characteristics that occur during selected heat treatments (contact grilling, roasting, roasting combined with microwaving, and steam cooking) of bell peppers at three maturity stages (green, yellow, and red), analyses of antioxidant activity, reducing sugar content, polyphenolic compound content, textural properties, and color coordinates in the L*a*b* system were carried out. Some of the processes used, such as contact grilling (15.43 mg GAE/g d.b.) and roasting combined with microwaving (15.24 mg GAE/g d.b.), proved to be beneficial as the total polyphenol content of green peppers (2.75 mg GAE/g d.b.) increased. The roasting (3.49 mg TE/g d.b.) and steaming (6.45 mg TE/g d.b.) methods decreased the antioxidant activity of yellow bell peppers (14.29 mg TE/g d.b.). Meanwhile, the roasting (0.88 mg Glc/g d.b.), contact-grilling (2.19 mg Glc/g d.b.), simultaneous microwaving and roasting (0.66 mg Glc/g d.b.), and steaming (1.30 mg Glc/g d.b.) methods significantly reduced the content of reducing sugars and reducing substances in red bell peppers (4.41 mg Glc/g d.b.). The studies proved that in order to preserve the antioxidant and bioactive properties of bell peppers, it is necessary to consider the use of appropriately selected heat treatments, depending on the different stages of maturity. The proper selection of adequate thermal treatment can not only increase digestibility, but also improve the bioavailability of bioactive substances from this raw material. [ABSTRACT FROM AUTHOR]

Processing with heat treatment has been reported to alter several therapeutic effects of turmeric. In Vietnamese traditional medicine, turmeric has been long used for bacterial infections, and roasting techniques are sometimes applied with this material. However, there have been no studies investigating the effects of these thermal processes on the plant's antibacterial properties. Our study was therefore performed to examine the changes that roasting produced on this material. Slices of dried turmeric were further subjected to light-roasting (80 °C in 20 min) or dark-roasting (160 °C in 20 min) processes. Broth dilution and agar-well diffusion methods were applied to examine and compare the effects of ethanol extracts obtained from non-roasted, light-roasted and dark-roasted samples, on a set of 6 gram-positive and gram-negative bacteria. In both investigations, dark-roasted turmeric was significantly less antibacterial than non-roasted and light-roasted materials, as evident by the higher values of minimum inhibitory concentrations and the smaller diameters of induced inhibitory zones. In addition, dark-roasting was also found to clearly reduce curcumin contents, total polyphenol values and antioxidant activities of the extracts. These results suggest that non-roasting or light-roasting might be more suitable for the processing of turmeric materials that are aimed to be applied for bacterial infections. [ABSTRACT FROM AUTHOR]

Summary: In this work, a novel roasting method for virgin rapeseed oil (VRO) production was proposed. The effect of infrared roasting (IR) on oxidation stability, Maillard reaction, glucosinolate degradation and volatiles of VRO was evaluated at 110–170 °C. The results showed that VROs from IR exhibited better oxidation stability (higher oxidative stability index and DPPH radical scavenging activity) of VROs than that from traditional roller roasting (TRR). This was attributed to the higher contents of tocopherols (748.78 mg kg−1) and canolol (680.69 mg kg−1) measured in IR‐VROs than tocopherols (682.15 mg kg−1) and canolol (564.28 mg kg−1) in TRR‐VROs. IR could provide a more effective thermal fracture of rapeseed, facilitating to higher releases of tocopherols and canolol. Moreover, during IR, free amino acid (from 25.60 to 15.03 mg kg−1), reducing sugars (from 7.65 to 2.04 mg kg−1) and glucosinolate (from 28.73 to 13.00 mg kg−1) were decreased more than TRR, especially at 150 °C, indicating more intense Maillard reaction and glucosinolate degradation. Hence, more nitriles/isothiocyanates (657.43 μg kg−1) and pyrazines (269.64 μg kg−1) were generated in IR‐VROs than TRR‐VROs (600.82 and 163.89 μg kg−1, respectively). From sensory analysis, the flavour profile of IR‐VRO was more than TRR‐VRO at 150 °C. IR holds the potential to produce VROs with better flavours. [ABSTRACT FROM AUTHOR]

Introduction: Barnyard millet, an ancient grain that serves as a staple food and a key component of many diets, requires processing before consumption. Roasting is a common processing method that can enhance millet palatability. However, it is important to ensure that the nutritional properties are well preserved. Hence, this study investigated the influence of roasting on the proximate composition, amino acid composition, total phenolic content (TPC) and antioxidant activity of the whole grain barnyard millet sample. Method: The roasted sample of whole grain barnyard millet was roasted in the oven at 110? for 10 minutes and used for proximate analysis and amino acid composition. Meanwhile, TPC and DPPH were performed using the ethanol extract of a roasted whole-grain barnyard millet sample. Results: This study found a significant (p<0.05) of 14.22% reduction in moisture content in roasted millet compared to non-roasted millet. The roasted millet sample showed a higher fat content (p<0.05) compared to the non-roasted millet sample, with values of 5.08±0.24% and 4.38±0.24%, respectively. The total amino acid content of the non-roasted sample was 116.76±11.31ng, while the roasted sample had a value of 123.51±0.23.22ng. In addition, the TPC and antioxidant activity were found significantly higher (p<0.05) in the roasted sample than in the non-roasted sample of whole grain barnyard millet. Conclusion: The roasting method should be considered in processing of the whole grain barnyard millet to enhance the nutrient composition and boost its functionality. [ABSTRACT FROM AUTHOR]

Nigella sativa, commonly known as the black seed, is a culinary spice therapeutic against many ailments. Common preparation practice of roasting or heating the seeds often deteriorates bioactive compounds, which can be remedied with superheated steam (SHS). With roasting temperatures of 150, 200, and 250°C and roasting times of 10, 15, and 20 min, convection and SHS roasting media were tested, and their effects on proximate analysis, antioxidant assays, and oil quality were evaluated. For proximate content, moisture significantly decreased from 9.08% in unroasted seeds to 4.18%–1.04% in roasted seeds, while fat increased to as high as 44.76% from 32.87% in unroasted seeds. Roasting only slightly increased ash content and had no significant impact on protein and carbohydrate content. SHS roasted black seeds had better DPPH (2,2‐Diphenyl‐1‐picrylhydrazyl) radical scavenging capacity (RSC) than convection roasted seeds. DPPH RSC decreased with elevated roasting time and temperature, conversely related to total phenolic content, which increased with increased roasting time and temperature. Oil of roasted seeds developed an increasingly intense brown color from an initial light, yellow, unroasted oil with better extraction efficiency in SHS roasting. For oil quality analysis, free fatty acid values were significantly lower in both roasted samples. Peroxide value was initially recorded at 84 in convection and 48 (meq O2/kg of oil) in SHS roasted samples. In contrast, p‐anisidine values were initially recorded at 28.36 in convection roasted samples compared to 23.73 in SHS roasted samples. Based on all quality analyses, SHS showed better potential in black seed quality preservation. [ABSTRACT FROM AUTHOR]

The article deals with the use of damaged cocoa beans in the cosmetics industry. The "Damaged Beans" project by Fraunhofer IVV and its Brazilian partner UNICAMP aims to identify new value creation potentials for damaged cocoa beans. Due to their lower costs and the additional active ingredients of the plant, damaged cocoa beans can be an advantage for cosmetic products. The project focuses on the effects of fermentation, drying, roasting, and pressing on the yield and properties of cocoa butter, proteins, and secondary plant substances. The goal is to develop a more efficient and cost-effective processing chain for damaged cocoa beans. [Extracted from the article]

Advanced glycation end products (AGEs) and heterocyclic amines (HAs) are two kinds of important harmful products formed simultaneously during the thermal processing of proteinaceous food. In this paper, the effect of roasting conditions on the formation of AGEs and HAs, as well as active carbonyl intermediates in common peanut (C−peanut) and high-oleic acid peanut (HO−peanut) was studied simultaneously for the first time. In general, with the increase in roasting temperature (160–200 °C) and time, the contents of AGEs, HAs and active carbonyl intermediates (i.e., glyoxal (GO) and methylglyoxal (MGO)) significantly increased in peanuts. Four kinds of HAs (i.e., AαC, DMIP, Harman and Norharman) were observed in roasted peanuts, of which Harman and Norharman accounted for about 93.0% of the total HAs content after roasting for 30 min at 200 °C. Furthermore, a correlation analysis among AGEs (i.e., Nε-(1-Carboxymethyl)-L-lysine (CML) and Nε-(1-Carboxyethyl)-L-lysine (CEL)), HAs, GO and MGO was conducted. Most of these compounds showed an excellent positive linear relationship (p ≤ 0.001) with each other. The evident increase in GO and MGO contents implied an increase in not only the content of AGEs but also HAs. However, contents of AGEs and HAs showed no significant difference between roasted HO−peanut and C−peanut. This study would provide a theoretical basis for simultaneously controlling the levels of AGEs and HAs in thermal processed peanut foods. [ABSTRACT FROM AUTHOR]

This study aimed to compare the aroma profiles of Sorbara and Spergola grapevine prunings roasted at different temperatures (120, 140, 160, 180, 200, and 240 °C). One potential application of grapevine prunings is their use as infusion chips to enhance and improve the aging processes of alcoholic beverages and vinegars. Aromatic compounds impart unique flavors and contribute to the complexity of the final products. Thermogravimetry–mass spectrometry coupled with evolved gas analysis (TGA-MS-EGA) was conducted to identify the thermal steps at which substantial changes occurred in the wood matrix. Solid-phase microextraction–gas chromatography–mass spectrometry (SPME-GC-MS) was used for the analysis of volatile compounds. Several key volatile compounds were identified, showing variations in their concentrations as a function of cultivar and roasting temperature. Furan derivatives, such as furfural, and phenolic compounds, such as guaiacol and vanillin, were the two main chemical classes of volatile compounds that predominantly defined the aroma of grapevine chips roasted above 180 °C. At lower roasting temperatures, some aldehydes, such as hexanal and terpenes, defined the aroma profiles of the samples. By repurposing waste materials, this application offers a pathway for environmentally conscious viticulture and sustainable practices within the food industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Black cumin seeds (black seed; BS) contain various bioactive compounds, such as thymoquinone (TQ). Roasting and ultrasound‐assisted enzymatic treatment (UAET) as pre‐treatments can increase the phytochemical content in the BS oil. This study aimed to investigate the effects of pre‐treatments on the TQ content and the yield of the BS oil and to profile the composition of defatted BS meal (DBSM), followed by evaluating antioxidant properties of the DBSM. RESULTS: The extraction yield of crude oil from BS was not affected by the roasting time. The highest extraction yield (47.8 ± 0.4%) was obtained with UAET cellulase‐pH 5 (enzyme concentration of 100%). Roasting decreased the TQ content of the oil, while the UAET cellulase‐pH 5 treatment with an enzyme concentration of 100% yielded the highest TQ (125.1 ± 2.7 μg mL−1). Additionally, the UAET cellulase‐pH 5 treatment increased total phenolics and flavonoids of DBSM by approximately two‐fold, compared to roasting or ultrasound treatment (UT) alone. Principal component analysis revealed that the UAET method might be more suitable for extracting BS oil with higher TQ content than roasting and UT. CONCLUSION: Compared to roasting or UT, using ultrasound along with cellulase could improve the oil yield and TQ in the oil from BS and obtain the DBSM with higher phenolics, flavonoids, and antioxidant activity. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The present study was focused on microwave (dielectric) roasting (300-600 W, 5-15 min) on the physical, textural, color, and grinding of black pepper. The microwave roasting is a volumetric heating that causes rapid removal of moisture, and internal pressure generated inside the seed tends to change the physiology and physical attributes. An increase in roasting power and time increased the geometric mean diameter (5.216 to 6.283 mm), sphericity (0.883 to 0.927), aspect ratio (0.853 to 0.914), and surface area (85.560 to 124.262 mm2) of black pepper. Whereas the significant (p < 0.05) reduction was observed in 100 grain weight (7.55 to 5.63 g), bulk density (500.97 to 251.38 kg/m3), fracturability (72.99 to 1.78 N), and hardness (63.65 to 1.61 N). Roasting led to browning, and a significant reduction was observed in the color parameters, L ∗ (22.82 to 17.76), a ∗ (2.47 to 0.56), and b ∗ (2.41 to -0.75) with a significant (p < 0.05) increase in total color difference (0.96 to 5.30). Roasting also increased the particle size distribution in grounded power, and the mean particle size increased from 121.72 to 146.14 μm. [ABSTRACT FROM AUTHOR]

This study investigates the effects of moisture content control on the characteristics, properties, and in vitro starch digestion of roasted rice powder made from natural high-resistant starch (RS) rice varieties. The results demonstrate that adjusting the moisture content before roasting significantly affects the RS content of the roasted rice powder. Among various moisture levels tested, the addition of 15% water (rice-to-water ratio of 85:15) before roasting resulted in the highest RS content, reaching 22.61%. Several key parameters of the rice samples before and after optimal moisture control were analyzed, including thermal stability, chain length distribution, volatile flavor composition, and scanning electron microscopy. Additionally, in vitro digestion properties were measured. The findings revealed that the volatile flavor compounds in the high-RS roasted rice significantly increased compared to non-roasted rice. Moreover, the thermal stability of the rice samples improved, and the chain length distribution exhibited significant changes. The water absorption and expansion properties were significantly lower in the high-RS roasted rice. Furthermore, the in vitro starch digestion of the roasted flour made from high-RS rice showed a significantly lower digestion rate compared to common rice, indicating a lower starch hydrolysis index in high-RS rice with the sbe-rs genotype. Overall, the roasting process of natural high-RS rice modifies its characteristics, increases the RS content, enhances the flavor, and results in a lower starch digestion rate compared to common rice. This study provides valuable data for the food industry to promote the application of high-RS rice varieties with mutations in the SBEIIb gene, such as Youtangdao2 (YTD2). [ABSTRACT FROM AUTHOR]

The method of roasting coffee beans was invented by the Arabs of Yemen, who then spread the method to Egypt and Turkey, and finally worldwide. This paper provides a detailed understanding of coffee beans from a chemical perspective, including discussions on identification of two coffee bean varieties--Arabica and Robusta, the chemical process of coffee roasting, and the pore structure of coffee beans. [ABSTRACT FROM AUTHOR]

As the economy recovered from the COVID-19 epidemic, the price of Li 2 CO 3 skyrocketed to the highest. Recovery of lithium from spent lithium-ion batteries (LIBs) is significant for addressing lithium shortage and environmental issues. Sulfation roasting is often accused of being unsustainable and not environmentally friendly due to the consumption of expensive sulfation reagents and emission of SO 2. Herein, a novel and green recycling process for selective separation of lithium from spent LiMn 2 O 4 (LMO) batteries was proposed based on a SO 2 emission free sulfation roasting with waste copperas. Lithium in the cathode power were selectively sulfated into soluble Li 2 SO 4 with a conversion of 99.50%, while manganese was riched as insoluble oxides. At low temperature (e.g. 400 °C), LMO were difficult to be sulfated due to the limited sulfation ability of SO 4 2- and mass transfer. When the roasting temperature reached 700 °C, SO 2 was produced and the generated SO 2 reacted in situ with the LMO to form Li 2 SO 4 and MnSO 4 , preventing SO 2 emissions into the atmosphere. As temperature continued to increase, the MnSO 4 acted as a sulfation reagent and sulfated the unreacted LMO. All the sulfur was immigrated in Li 2 SO 4 , rather than being emitted as SO 2. [Display omitted] [ABSTRACT FROM AUTHOR]

Roasting is considered the commonest processing method applied to foods, it affects both phytochemicals and sensory attributes. In the present study, the effect of varying roasting parameters on sensory attributes was determined, as well as scavenging property against free radicals (DPPH) and polyphenolic content (TPC and TFC) of whole peanut kernels. Whole peanut kernels were roasted at different temperatures (130-150 °C) with various durations (5-20 min). Finding revealed that peanuts roasted at 130, 140, and 150 °C for 15, 10, and 5 min, respectively, received significantly the highest (p<0.05) sensory scores in all the parameters investigated. Therefore, they were selected for TPC, TFC, and DPPH assays. All three assays were found to increase during roasting compared to the unroasted counterpart. Peanuts that were roasted at 140 °C for 10 min, had the highest total phenolic contents of 67.26 ± 1.77 mg GAE/g while those roasted at 150 °C for 5 contained the highest TFC of 12.91 ± 0.56 mg QE/g. The highest DPPH radical scavenging activity was detected in the sample roasted at 140 °C for 10 min with an IC50 value of 417.44 μg/mL. Roasting significantly affected the bioactive contents as well as the scavenging activity of the whole peanut. [ABSTRACT FROM AUTHOR]

It is well-known that the mining industry in Chile and the world is searching for eco-friendly, highly efficient mineral treatments. This is because the content of toxic elements such as arsenic, antimony, and bismuth have increased in the copper concentrates in the last years. This trend has affected the market of this metal, as well as increased the potential of producing solid wastes that represent a threat to the environment. In this paper, a review on the fundamentals of the current treatments aimed at removing arsenic, antimony, and bismuth from copper concentrates under roasting conditions is presented. The literature survey included the research conducted from 2000 until now and is focused on the different types of roasting of copper concentrates reported in the literature. A summary of the experimental conditions and major findings of each work is discussed. Depending on the type of roasting, the behavior of arsenic, antimony, and bismuth species during the experiments is analyzed. [ABSTRACT FROM AUTHOR]

• Roasting tests of all-solid-state lithium-ion batteries (ASS-LIBs) were performed. • The chemical speciation changes of the ASS-LIBs caused by roasting were determined. • The metals showed complicated reaction paths owing to O 2 , S, P, and C coexistence. • The roasting parameters need to be accurately controlled for high metal recovery. All-solid-state lithium-ion batteries (ASS-LIBs) are expected to replace current liquid-based LIBs in the near future owing to their high energy density and improved safety. It would be preferable if ASS-LIBs could be recycled by the current recycling processes used for liquid-based LIBs, but this possibility remains to be determined. Here, we subjected an ASS-LIB test cell containing an argyrodite-type solid electrolyte (Li 6 PS 5 Cl) and nickel–manganese–cobalt-type active material (Li(Ni 0.5 Mn 0.3 Co 0.2)O 2) to roasting, a treatment process commonly used for recycling of the valuable metals from liquid-based LIBs, and investigated the changes in chemical speciation. Roasting was performed at various temperatures (350–900 °C), for various times (60–360 min), and under various oxygen fugacity (air or O 2) conditions. The chemical speciation of each metal element after roasting was determined by sequential elemental leaching tests and X-ray diffraction analysis. Li formed sulfates or phosphates over a wide temperature range. Ni and Co followed very complicated reaction paths owing to coexistence of S, P, and C, and they formed sulfides, phosphates, and complex oxides. The optimum conditions for minimizing formation of insoluble compounds, such as complex oxides, were a roasting temperature of 450–500 °C and a roasting time of 120 min. The results indicated that although ASS-LIBs can be treated by the same roasting processes as those used for current liquid-based LIBs, the optimal roasting conditions have narrow ranges. Thus, careful process control will be needed to achieve high extraction percentages of the valuable metals from ASS-LIBs. [ABSTRACT FROM AUTHOR]

Oven roasting (OR) could induce hierarchical structural changes in starch, which is fundamental for altering the pasting and hydration properties of cereal flour. OR makes proteins denatured and peptide chains unraveled or rearranged. OR could alter compositions of cereal lipids and minerals. Although OR may degrade phenolics, their release from bound forms is predominant when mild/moderate conditions are exerted. Hence, some OR‐modified cereals even exhibit many physiological functions, such as anti‐diabetic and anti‐inflammatory activity. Furthermore, these minor components interplay with starch/protein via physical entrapment, non‐covalent interactions, or cross‐linking. The structural changes and interactions modulate functionalities of OR‐modified cereal flour, its dough/batter property, and related staple food quality. Compared with hydrothermal or high‐pressure thermal treatments, proper OR even induces greater enhancement in technological quality and bioactive compounds release. Given the simple operation and low cost, it is worth utilizing OR for the development of sensory‐appealing healthy staple foods. [ABSTRACT FROM AUTHOR]

The present research aimed to evaluate the effects of roasting and microwave thermal processes along with pH change on the amount of residues of three commonly used antibiotics, enrofloxacin, oxytetracycline and sulfadiazine in chicken meat. For this purpose, first the three antibiotics were added to the chicken meat samples in amounts 4 times the remaining limit. Meat samples containing residues of each antibiotic were subjected to roasting (at 200 °C for 30 minutes) and microwave (at 100 °C for 3 minutes) treatments at pH 5.8 and 4.8. Then, the residual amount of each of the antibiotics was investigated by high -performance liquid chromatography (HPLC) along with colorimetry and evaluation of cooking loss. The results showed that both treatments were able to significantly reduce the amount of antibiotic residues, but both processes were more effective at pH 4.8 than 5.8 (P<0.05). The highest amount of reduction of antibiotic residue at pH 4.8 in both microwave and roasting treatments was observed in oxytetracycline residue with 76.2 and 72.4% respectively. Roasting and microwave treatments decreased L* index, but a* index decreased in roasting and increased in microwave, and b* index increased in microwave, but there was no significant change in roasting. Also, the amount of cooking loss in roasting in the range of 58 to 71% was more than that of microwave in the range of 48 to 62% (P<0.05). Finally, microwave treatment can be introduced along with reducing the pH of chicken meat to 4.8 as the best treatment to reduce antibiotic residues. [ABSTRACT FROM AUTHOR]

Recently, processed foods have become an important part of human eating habits. However, several processing techniques, such as dehulling and roasting, are applied to raw foods. Roasting is a thermal process that depends on temperature and time and improves the extraction yield of oil by generating pores in the oilseed cell walls. Sesame (Sesamum indicum L.) is an annual plant belonging to Pedaliaceae and is considered to be one of the oldest oil crops. Nowadays, the cultivation of this plant is economically important in several countries. This review clarifies the botanical characteristics and nutritional importance of sesame seeds, reviews their phytochemical composition, and discusses the effects of dehulling and roasting on their nutritional quality. S. indicum, which is known to contain several classes of bioactive compounds, including fatty acids, phenolic compounds, amino acids, and lignans, has been reported to possess a wide range of biological activities such as antioxidant, anti-inflammatory, anticancer, antimicrobial, and cardioprotective activity; however, processing such as dehulling eliminates undesirable chemical constituents while roasting provides the best chemical composition at moderate temperatures. [ABSTRACT FROM AUTHOR]

Roasted carob powder is produced from the pulp of carob fruit (Ceratonia siliqua L.). In this study, the roasting process was optimized using a central composite design of the response surface methodology in order to maximize the product quality and minimize processing temperature (100–160 °C) and time (5–60 min). Analysis of variance qualified the effect of roasting with different types of models: first, linear models for dry matter, glucose, and ABTS scavenging activity; then, correlative models for proteins, total dietary fibers (TDF), and polyphenols; and last, quadratic models for total flavonoids, flavonols, and DPPH scavenging activity (all significant at p < 0.05). The process increased the antioxidant activity, TDF, and total polyphenol contents, while the concentration of the other components decreased. The optimal conditions for carob roasting were 100 °C for 37.32 min. [ABSTRACT FROM AUTHOR]

Summary: This current work presents a meta‐analysis to determine coffee bean specifications [types (Arabica and Robusta), roasting degree (light, medium and dark), roasting condition (time and temperature) and geographical origins by countries (Brazil, India and Thailand)] with the highest antioxidant activity. A total of 12 articles and 189 data points were employed for meta‐analysis of subgroups. The results showed that the Arabica coffee bean was reported to have the highest antioxidant activity as assessed by ferric reducing antioxidant power (FRAP) and 2,2‐azinobis‐3 ethyl benzothiazoline‐6‐sulfonic acid (ABTS). In addition, the light roasting degree of coffee beans produced the highest antioxidant activity as assessed by FRAP and 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH). Roasting degree is a better parameter to obtain coffee beans with higher antioxidant activity compared to roasting conditions. Coffee from Brazil and India was found to have higher antioxidant activity compared with coffee from Thailand. This study concludes that Arabica coffee beans from Brazil or India with a light roasting degree are expected to have high antioxidant activity. [ABSTRACT FROM AUTHOR]

The Italian espresso coffee is a very popular drink worldwide. Roasting of coffee grains represents a key step in the development of the beverage characteristics and aroma. A coffee blend (80% Coffea arabica and 20% canephora) of a well-known Italian coffee firm underwent 3 roasting conditions (standard with end temperature of 216 °C, below standard with end temperature of 206 °C and over standard with end temperature of 223 °C) to study the effects of processing conditions on the chemical composition of the coffee powder and on the chemical and sensory characteristics of the espresso beverage. Proximate composition, polar and semi-polar metabolome (amino acids and aliphatic acids), chlorogenic acids, and volatile organic compounds were determined in the powder and beverage by means of standard methods, HPLC-ESI(±)-HRMS, HPLC–PDA/ESI–MS and HS-SPME/GC–MS respectively. Changes induced in the powder and beverage by roasting conditions are described with heatmaps and correlation networks between polar metabolites and sensory characteristics of the espresso beverage are reported. The concentration of chlorogenic acids is inversely proportional to the roasting temperature and the lower is the roasting temperature, the higher is the acid taste in the espresso. Some volatile organic compounds might be analytical markers of the strength of the roasting process. Cream and body of drink are increased as roasting temperature increases. [ABSTRACT FROM AUTHOR]

Background: The Himalayan Echinochloa frumentacea (barnyard millet) is believed to be a nutritionally rich crop but remains underutilized. It is generally used after removing its seed coat (SC) through dehulling, and for making some food items, it is roasted before cooking. Such pre‐cooking processes, such as dehulling, roasting, and then cooking affect the nutraceutical potential of raw grains and food items prepared. Results: The effects of processing techniques are determined in terms of variation in proximate properties, antinutrients, phytochemicals, and antioxidants. The processing methods significantly (p < 0.05) affected the nutraceutical potential of the processed form of barnyard millet. While comparing the nutritional properties of raw and dehulled barnyard millet, it was found that the SCs are nutritionally very rich, which are generally either discarded or become part of cattle feed. Vitamin C, E, alkaloids, and oxalate content were found to decrease after roasting. Cooking had decreased the carbohydrate, fat, vitamin C, vitamin E, alkaloid, oxalate, and iron content in both food types in comparison to the pre‐cooking stage of the millet samples, while tannin content was found to have increased. Conclusion: In this work, the variation in the nutritional parameters and phytochemicals of barnyard millet was studied during the processing steps, such as dehulling, roasting, and cooking. Roasting had shown a lesser impact on the selected nutritional properties of uncoated seeds, while cooking had changed some of the nutritional properties. The SC was also found to be nutritious, so it needs to be explored further for its efficient utilization. [ABSTRACT FROM AUTHOR]

This investigation is aimed at elucidating the effects of roasting degree and extraction method on coffee beverages prepared with beans from Asia. According to the results with the improvement of the roasting degree, a decrease in titratable acidity, total phenolic compounds, the concentrations of chlorogenic acid and trigonelline, and total antioxidant capacity was observed. Cold coffee beverages showed higher total sugar and trigonelline. The volatile components, such as pyridine, furan-2-yl-methyl acetate, 2-furanemethanol, and 5-methylfurfural, were also affected by roasting degree and extraction methods. Cold brew coffee exhibited higher intensities of enzymatic flavor and sweetness. Furthermore, the principal component analysis revealed a distinct difference in coffee characterization in roasting degree in cold coffee brews than in hot ones. The results indicate that roasting degree affects physicochemical and sensory properties more than extraction temperature. Additionally, there were significant differences in coffee characteristics between cold and hot brew coffee. [ABSTRACT FROM AUTHOR]

Plant-based protein has been increasingly demanded as a sustainable protein source. Sea lettuce (Ulva lactuca) is one of the potential sources as plant protein due to its high protein content. During processing, the sea lettuce is exposed to heat which might affect its nutrition, particularly the protein quality. This study aimed to evaluate two different cooking processes on the nutritional quality of the sea lettuce based on the proximate and protein quality analyses. The samples were raw, roasted, and boiled-roasted sea lettuce. All treatment using temperature 100°C. The protein quality was assessed by in-vitro protein digestibility, solubility, and amino acid profiles. The result showed that boiling treatment followed by roasting treatment had significantly higher protein content, amino acid score and essential amino acid index, and predicted-protein efficiency ratio compared with the value of roasting treatment only. It resulted in protein content of 18.87% (dry basis), amino acid score of 37.96%, essential amino acid index of 79.41% and predicted-protein efficiency ratio of 2.58. Therefore, boiling followed with roasting process is recommended to maintain the nutrition quality of sea lettuce. [ABSTRACT FROM AUTHOR]

Chocolate is a highly appreciated food that develops its characteristic flavors in large part during the roasting of cacao beans. Many functional classes have been noted for their importance to chocolate flavor, including volatile organic sulfur compounds (VSCs). Despite this, the effect of roasting on the concentration of VSCs has never been thoroughly assessed. Here, we studied the effects of roasting temperature, time, and cacao origin on the formation of VSCs. Twenty-seven 100% chocolate samples made from cacao from three different origins and roasted according to an I-optimal experimental design were analyzed by comprehensive gas chromatography with sulfur-selective detection (GCxGC-SCD). For two compounds, dimethyl disulfide and dimethyl trisulfide, the effects of roasting time, roasting temperature, and cacao origin were modelled using response surface methodology and semi-quantified relative concentration. Overall, roasting increased the number of sulfur-containing volatiles present in chocolate, with a total of 28 detected, far more than previously thought. Increased roasting time and especially roasting temperature were found to significantly increase the concentration of VSCs (p < 0.05), while cacao origin effects were only seen for dimethyl disulfide (p < 0.05). The identity of most VSCs remains tentative, and more research is needed to unravel the impact of these volatiles on flavor perception in chocolate. [ABSTRACT FROM AUTHOR]

Arsenious and sulphur-bearing micro-disseminated gold ore is a kind of typical refractory Carlin-Type. The gold in Carlin-Type gold ore grains is distributed finely, existing as invisible or submicroscopic gold, encapsulated in arsenopyrite and pyrite. The technical difficulty of treatment Carlin-Type gold ore lies in how to release the fine gold wrapped in pyrite and arsenopyrite. In this study, the oxidation roasting pre-treatment technique was used to treat the Carlin-Type gold ore. This included a two-stage roasting process: the arsenic was removed in the first roasting process, and the sulphur was removed in the second roasting process. The thermodynamic of the roasting process was analyzed, and the mineral phase evolution of the roasting process was investigated by using XRD, SEM and EDS. Finally, the influence of sodium cyanide dosage and leaching time on leaching efficiency was investigated. The results suggest that for the first roasting temperature at 550 °C, and the second roasting at temperature 700 °C with air flow 2.5 L/min, the sodium cyanide dosage is 1.75 kg/t and leaching time is 27 h; a good leaching efficiency is obtained with 83.85%. [ABSTRACT FROM AUTHOR]

Summary: Food fortification with whole or de‐hulled pulse flours is a challenge since food products usually have inferior structure and sensory characteristics. In this study, wheat flour was substituted with whole or de‐hulled pea flour (20 wt%) processed under pre‐treatments of microwave and roasting to prepare novel Chinese steamed bread (CSB), respectively, and the effect on pasting property of the dough, and its influence on physical quality, sensory attributes, and nutritional profile (amino acids, dietary fibre, and mineral micronutrients) of the resulting CSB was investigated. The addition of pretreated pea flour increased the peak, retraction and final viscosity of the dough and increased the specific volume and decreased the hardness of the final product due to the enhanced pasting characteristics, compared to the control. Microwave and roasting presented different patterns affecting gas cell structure, amino acid composition, dietary fibre content, and essential minerals, depending to a large extent on the milling fraction. Among all the treatments, microwave‐treated de‐hulled pea flour was more effective in modifying the cellular structure, improving amino acid composition and dietary fibre content of the resultant CSBs. This study offers useful knowledge for creating functional CSB that satisfies the needs for both sensory appeal and nutritional balance. [ABSTRACT FROM AUTHOR]