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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]

In this study, the effect of steaming and roasting treatment on the physicochemical and functional properties of walnut kernel at 95°C for different time (15, 20, and 30 min) was investigated. Steaming and roasting treatments significantly increased the enthalpy change for protein denaturation, in‐vitro digestibility, viscosity, storage modulus (G′) and loss modulus (G″) (p < 0.05), the order from high to low was steaming (7.11–8.69 J g−1; the gastric and intestinal digestion: 1.21%–17.83% and 1.51%–27.31%, respectively; 134.04–450.49 Pa s; 214.28–1047.14 and 61.72–196.09 Pa) > roasting (6.24–7.07 J g−1; the gastric and intestinal digestion: 1.26–15.42% and 1.21–22.37% a, respectively; 16.92–86.07 Pa s; 6.58–209.85 and 3.08–67.14) > untreated (4.53 J g−1; the gastric and intestinal digestion: 0.24%–4.18% and 1.00–7.58%, respectively; 17.06 Pa s; 5.78 and 1.79 Pa). All samples contained the essential amino acids, the amino acid score of samples by steaming was the highest. In addition, the protein of walnut kernel after heating treatment contained more α‐helix and random coil structures compared to the untreated sample, while β‐sheet and β‐turns structures decreased. Moreover, the thermal treatment could cause the changes of the water/oil holding capacity, foaming and emulsifying properties of walnut kernel flour. When there were differences between the results of steaming and roasting samples, it was concluded that the water played an important role in steaming. These results suggested that the thermal treatment as an effective approach could improve the physico‐chemical, structural and functional properties of walnut kernel and be potentially applied in the food processing. [ABSTRACT FROM AUTHOR]

Effects of hot air circulation roasting temperature on cashew nut sensory and aroma profiles were assessed in this study. Optimal roasting at 130°C for 20 min yielded a uniform, glossy appearance and rapid water loss. Sensory and electronic nose (E‐nose) analyses indicated enhanced sweet, milky, and fatty aromas. Gas chromatography–mass spectrometry identified more than 180 volatile compounds. Roasting at 150°C for 20 min produced a burnt aroma, with a decrease in alkenes and aromatic hydrocarbons and an increase in alkanes, acids, ketones, and pyrazines. Principal component analysis distinguished between 130 and 150°C roasting samples, and key volatile compounds included phenylethanol, 1‐octen‐3‐ol, naphthalene, (−)‐alpha pinene, trans caryophyllene, 2,5‐dimethylpyrazine, 2‐methylbutyr‐aldehyde, heptaldehyde, 2,3,5‐trimethylpyrazine, and n‐octanol. Compared to traditional roasting, hot air circulation roasting offers efficiency, convenience, energy savings, and environmental benefits. Practical applications: Cashew nuts are esteemed as a nutritious treat mainly due to their profound taste and elevated nutrient content. This research explored the influence of applying hot air circulation during the roasting procedure on various aspects of physical and chemical properties, flavor, and energy consumption. By establishing a systematic theoretical model of the process, this work can effectively manipulate the roasting parameters to attain an optimal flavor profile desirable for cashew nuts. Moreover, the efficiency of this novel approach outperforms conventional techniques, offering substantial energy cost savings, and showcasing its virtues of high efficacy, eco‐friendliness, and environmental preservation. The investigation revealed that utilizing hot air circulation leads to cashew nuts possessing a superior gustatory sensation and nutritional profile. Therefore, it can safely be stated that hot air circulation roasting could serve as an exemplary methodology for household nut manufacturing, thereby warranting further consideration of this innovative technique in private nut production. [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]

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]

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]

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]

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]

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]

This study was conducted to assess the effect of two thermal treatments, viz. roasting and pan frying (deep frying), on nutritional profile, aflatoxin, and capsaicin content in green chilies. Green chilies were subjected to roasting and frying to reduce the aflatoxin contamination, besides retaining their pungency and nutritional profile. Reversed‐phase HPLC was employed to determine the levels of aflatoxins B1, B2, G1, and G2 in thermally treated and control samples. The proximate compositions of roasted and fried chili samples were significantly (p ≤.05) different from raw chili (control), except ash content. Vitamin A levels decreased significantly (p ≤.05) during roasting and were undetected in fried chili samples. Likewise, vitamin C was undetected in both roasted and fried chili samples. Significantly decreasing (p ≤.05) trends were noticed in capsaicinoids viz. capsaicin and dihydrocapsaicin contents including Scoville Heat Units (SHU) during roasting and frying. However, retention of capsaicinoids was higher in roasted chilies (730.00 ± 4.90 mg/kg) than fried samples (502.56 ± 5.10 mg/kg). The levels of all the four major aflatoxins (AFs)‐ AFB1, AFB2, AFG1, and AFG2 recorded in control were much higher than the limits prescribed by the European Union for spices. Both thermal treatments (roasting and frying) employed proved to be effective in reducing aflatoxins like AFB2, AFG1, and AFG2 in chilies to below the prescribed limits, while as the level of AFB1 was reduced below the limits by only the frying method. This study therefore indicated the substantial impact of frying on aflatoxins. [ABSTRACT FROM AUTHOR]

Summary: Chickpea is gaining importance as a sustainable plant‐based protein source due to its high protein content and protein bioavailability. Malting and roasting, the traditional processing techniques, can be used to improve the protein quality of chickpea. The effect of two processing techniques on the water‐soluble albumin fraction, salt‐soluble globulin fraction, alcohol‐soluble prolamin fraction, and alkali‐soluble glutelin fraction was studied. Globulin content decreased from 45.85% to 37.08%, whereas the albumin fraction was found to increase from 4.16% to 7.08%, after 6 days of germination. It was observed that malting and roasting resulted in significant changes in the protein quality parameters and decrease in anti‐nutritional factors. Tannin content reduced by 53.18% and 40.44%, and the trypsin inhibitor activity reduced by 14.91% and 34.59% after malting and roasting, respectively. The protein efficiency ratio, biological value, and nutritional index improved due to malting and roasting. The biological value of raw chickpea protein was found to be 74.97%, and it increased to 81.89% and 79.27% on malting and roasting, respectively, and protein digestibility values were also increased. Microstructural and diffraction patterns of chickpea flours were examined. Amino acid scores for infants and adults were calculated, and sulphur‐containing amino acids were found to be the limiting amino acids in chickpea. [ABSTRACT FROM AUTHOR]

BACKGROUND: Chili is hygroscopic and needs a fast‐drying method before feeding into pulverizers. The far‐infrared radiation (FIR) roasting technique provides various benefits, such as higher drying rates within a short duration, reduction of mycotoxins, and improvement in the textural quality of agricultural produce. In addition, thin‐layer modeling supports understanding the drying kinetics of agricultural produce. Therefore, the objective of this research was to study the thin‐layer drying characteristics and color of whole chili pod and its components (i.e. seeds, pedicel, and placenta) of sun‐dried chili during FIR roasting. The samples were dried at 7.76 μm (100 °C), 6.12 μm (200 °C), 5.056 μm (300 °C), and 4.30 μm (400 °C) by exposing them to FIR in a single layer and the drying kinetics were studied using the Midilli model. Further, the color variation during FIR roasting was studied. RESULTS: FIR roasting of chili pods and their components (i.e. seeds, pedicel, and placenta) shows a falling rate drying period at each wavelength. The moisture content decreased with decreasing FIR wavelength. The ∆E values for pods, pedicel, and placenta were increased during FIR roasting. The Midilli model results in R2 and root‐mean‐square error value ranges of 0.7563–1.000 and 5 × 10−8–0.1238 respectively for the current study. The Midilli model at 300 °C shows that the FIR has minor variation compared with other FIR temperatures. CONCLUSION: FIR technology can be implemented to roast chili pods and their components (i.e. seeds, pedicel, and placenta) within a short period. Further, the application of FIR for roasting purposes desirably increases the color variation. The Midilli model can effectively describe the drying kinetics of the chili pods and their components during FIR roasting. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Phenolic compounds present in coffee beans could generate flavor and bring benefits to health. This study aimed to evaluate the impacts of commercial roasting levels (light, medium, and dark) on phenolic content and antioxidant potential of Arabica coffee beans (Coffea arabica) comprehensively via antioxidant assays. The phenolic compounds in roasted samples were characterized via liquid chromatography–electrospray ionization quadrupole time‐of‐flight mass spectrometry (LC‐ESI‐QTOF‐MS/MS). Furthermore, the coffee volatile compounds were identified and semi‐quantified by headspace/gas chromatography–mass spectrometry (HS‐SPME‐GC‐MS). Generally, for phenolic and antioxidant potential estimation, light roasted samples exhibited the highest TPC (free: 23.97 ± 0.60 mg GAE/g; bound: 19.32 ± 1.29 mg GAE/g), DPPH, and FRAP. The medium roasted beans performed the second high in all assays but the highest ABTS+ radicals scavenging capacity (free: 102.37 ± 8.10 mg TE/g; bound: 69.51 ± 4.20 mg TE/g). Totally, 23 phenolic compounds were tentatively characterized through LC‐ESI‐QTOF‐MS/MS, which is mainly adopted by 15 phenolic acid and 5 other polyphenols. The majority of phenolic compounds were detected in the medium roasted samples, followed by the light. Regarding GC‐MS, a total of 20 volatile compounds were identified and semi‐quantified which exhibited the highest in the dark followed by the medium. Overall, this study confirmed that phenolic compounds in coffee beans would be reduced with intensive roasting, whereas their antioxidant capacity could be maintained or improved. Commercial medium roasted coffee beans exhibit relatively better nutritional value and organoleptic properties. Our results could narrow down previous conflicts and be practical evidence for coffee manufacturing in food industries. [ABSTRACT FROM AUTHOR]

Particulate composites based on poly(lactic acid) (PLA) and poly(butylene succinate) (PBS) biopolymers have been formulated. Silver skin (SSK), the by‐product derived from the roasting of coffee beans, has been milled to micrometric size and added up to a 30 wt% of loading, without any previous treatment. The dynamic mechanical properties of the composites have been investigated, as well as the stability toward UV and IR radiation. The filler improves some mechanical properties such as the elastic modulus (E′) mostly in PBS. Photoaging experiments demonstrate that SSK, due to its polyphenols content and antioxidant activity, is able to protect both PLA and PBS from UV degradation, highlighting an added value of SSK waste‐based composites. [ABSTRACT FROM AUTHOR]

The effects of different processing methods on proximate composition, total phenolic content, antioxidant activity, lipid oxidation, and mineral contents of sunflower seeds produced in Far North Region of Cameroon were evaluated. Mean moisture, ash, lipid, protein, fiber, and carbohydrate contents of raw sunflower seeds were 6.60%, 2.55%, 44.65%, 20.17%, 4.08%, and 21.25%, respectively. The changes in moisture, ash (excepted in boiled samples), lipid, protein, fiber, and carbohydrate (excepted in roasted samples) were found to be significant for all cooking methods. Ash and lipid contents of samples roasted at 120°C were found to be significant when compared with other cooking methods. Antioxidant activity increased with treatment. After processing, the acid, peroxide, and thiobarbituric acid values increased significantly, whereas iodine value decreased. The roasting process improved the induction time, and samples roasted at 120°C were found to have the highest induction time (2.29 ± 0.09 hr). Raw sunflower seeds were good sources of potassium (K), magnesium (Mg), calcium (Ca), iron (Fe), zinc (Zn), and manganese (Mn). Increase in contents of Ca, Mg, Zn, Cu, and Fe was observed during processing. Roasting compared with boiling appeared to be the best cooking method of sunflower seeds concerning nutrient content, antioxidant stability, and lipid stability. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare pistachio (Pistacia vera L.) kernel volatile compounds (VCs) of "Siirt", "Uzun" and "Kirmizi" cultivars grown in Turkey, and also to determine the effects of traditional and industrial in‐shell roasting. The VCs were analyzed by using solid phase microextraction and gas chromatography–mass spectrometry. Regardless of cultivar, a total of 36, 55, and 65 VCs were identified in raw, industrial and traditional roasted pistachios, respectively. Limonene was the major terpene and the most important volatile compound in "Siirt" and α‐pinene in raw "Kirmizi" and "Uzun" but α‐terpinolene in their roasted counterparts. The heterocyclic and phenolic compounds reached a maximum in all three cultivars in traditional roasting compared to industrial roasting. Discriminant analysis based on volatile compounds classified the pistachios according to the roasting methods rather than cultivars. "Kirmizi" may be the most promising cultivar for traditional roasting regarding its highest pyrazine content. Practical Applications: The main object of the present study was to determine and compare volatile compounds (VCs) in three different pistachio (Pistacia vera L.) cultivars ("Siirt", "Uzun" and "Kirmizi") that are raw (not roasted), industrial and traditional roasted in‐shell. They are the main cultivars grown in Turkey. VCs from kernels were analyzed by using solid phase micro‐extraction and gas chromatography–mass spectrometry. VC profile and its abundance were dependent on both roasting methods and cultivar. Pyrrole, pyrazine and furan compounds were emerged by the roasting process. Pyrroles were higher than pyrazines in industrial roasting, with exception of "Kirmizi" but pyrazines were the highest heterocyclic compounds in traditional one, even being the dominant VC group in "Siirt" and "Kirmizi". Roasting process was a crucial factor for pyrazines, pyrroles, furans, phenolic compounds and also terpenes in "Siirt," "Uzun" and "Kirmizi" pistachios. "Kirmizi" may be the most promising cultivar for traditional roasting regarding its highest pyrazine content. [ABSTRACT FROM AUTHOR]

Summary: Specialty coffee (SC) has been showing an increasing interest from the consumers which appreciate its traceability and the peculiar flavours from each single origin. Additionally, the processes to which coffee fruits underwent to get green coffee characterise the beans in terms of macromolecules acting as substrates during the roasting. This work evaluates via sensory analysed eight SC, roasted at light, medium, and dark level, submitted to Italian espresso extraction, to assess how different roasting levels exalt the expected cup profile obtained by the suppliers via cupping in origin countries. Finally, roasted beans were characterised for physico‐chemical features (pH, titratable acidity, caffeine, melanoidins, polyphenols and acrylamide). Sensory analysis demonstrated that the intermediate roasting level and espresso extraction match better attributes from in‐origin cupping. Melanoidins (mmol g−1 coffee d.b.) was able to discriminate among roasting levels (light 0.12 ± 0.01; medium 0.13 ± 0.003; dark 0.14 ± 0.01; α = 0.05). Acrylamide analyses ensured compliance with the food safety standards (light 301.9 ± 37.2 ppb; medium 126.1±19ppb; dark 107.9 ± 22.5ppb). Physico‐chemical features were able to cluster samples from different origins within the same roasting level (α = 0.05). Results showed correlations (α = 0.01) between sensory analysis and physico‐chemical values: direct for caffeine and astringency, reverse for perceived acidity in relation to astringency, roasted, dried fruits and nutty notes. [ABSTRACT FROM AUTHOR]

BACKGROUND This study was carried out in order to investigate the role of post‐harvest methods and roasting degree on the sensory profile of Turkish coffees and to compare the results between two sensory panels: Turkey and Brazil. Bourbon variety of Arabica coffee beans processed by three different post‐harvest methods (natural, pulped natural and fully washed) and roasted at three different roasting degrees (light, medium and dark). RESULTS: Ground coffee in powder size was heated with cold water and prepared in a Turkish coffee machine. Twenty assessors – ten Turkish and ten Brazilian – were selected and trained to assess 20 flavor attributes of nine Turkish coffee samples. Sensory evaluation results showed that the effects of roasting method on flavor development were perceived more dominantly than effects of post‐harvest methods. For the first time, this study highlighted the sensory analysis of Turkish coffees assessed by Turkish and Brazilian assessors. CONCLUSION: Turkish coffee flavor profiles were significantly influenced by roasting method and no significant effects of post‐harvest method were observed. Sensorial properties of Turkish coffee were affected by several factors, such as geographical origin and techniques used for preparation of coffee beans, cultural tradition, lifestyle, social behavior and habit. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Summary: Although superheated steam (SHS) roasting has proved to be capable of improving selected quality of roasted Robusta coffee beans, impact of SHS roasting on aroma characteristics of the beans is not well understood. This study therefore aimed to investigate the effect of SHS roasting on aroma profiles and sensory characteristics of Robusta beans undergone SHS roasting at 190–250 °C; results were compared with those of beans roasted by hot air (HA). Sensory characteristics of selected samples were also compared with HA‐roasted Arabica beans. Forty five aroma compounds were identified; most were fully developed in beans roasted at 230 °C and tended to degrade in beans roasted at 250 °C. SHS roasting led to more extensive formation of aroma compounds contributing to caramel note, while helped reduce formation of major contributors to spicy, roasty and burnt notes. SHS‐roasted Robusta beans exhibited more resemblance to Arabica beans than their HA‐roasted counterpart. [ABSTRACT FROM AUTHOR]

Gari is a common cassava precooked dried semolina in sub‐Saharan Africa. Our study investigated the role of process parameters and mash water content on gari quality during traditional roasting stage. The statistical analysis for eight quality criteria revealed that gari quality is highly influenced by the process parameters adopted by the operators. To emphasise the twin impact of roasting parameters and mash water content, different mashes with varying water content were roasted leading to different adjustments of the roasting conditions according to the operators. When the variability of the water content becomes greater, a greater variability in the final quality of the obtained garis was observed between operators (lightness, swelling capacity, starch content, texture and colour). These results suggest that technological improvements to the gari process could be achieved by appropriate management of the roasting and dewatering parameters. [ABSTRACT FROM AUTHOR]

Summary: In order to evaluate the effect of steam addition during meat roasting, beef sirloin steaks were cooked at five humidities (0%, 25%, 50%, 75% and 100%) under 230 °C to a centre temperature of 71 °C. With increased humidity, heating rate generally increased and the cooked steak gradually lost the typical roasted appearance. Thiobarbituric acid‐reactive substances (TBARS) values generally increased, while carbonyl groups were not affected. Increased humidity promoted the formation of volatile aldehydes and alcohols, while pyrazines decreased significantly from 0% to 25% humidity. Steam‐assisted roasting inhibited the formation of heterocyclic aromatic amines (HAAs; except for IQ and Norharman). However, further increase in humidity (larger than 25%) did not have additional inhibition effect. Based on the results, it is recommended to roast beef with steam addition to reduce toxic HAAs, but the humidity should be kept at a relatively low level to maintain a typical roasted appearance and flavour profile. [ABSTRACT FROM AUTHOR]

Background: Quinoa is a pseudocereal with relatively high content of proteins and minerals that also contains mineral inhibitors such as phytate. The aim of the present study was to evaluate lactic acid fermentation and dry roasting on the nutritional quality and sensory attributes of quinoa. Various processes were evaluated, and quinoa grains were dry‐roasted, milled, and fermented, either with or without the addition of wheat phytase or activated quinoa phytase (added as back‐slop starter), for 10 hr. In other processes, raw quinoa flour was fermented for 10 hr or 4 hr and dry‐roasted. Hedonic sensory evaluation was then performed to evaluate the acceptability of the fermented flours prepared as porridges. Results: The combined dry roasting and fermentation processes significantly (p <.05) degraded phytate between 30% and 73% from initial content. The most effective process was fermentation of raw quinoa flour followed by dry roasting, which improved the estimated zinc and iron bioavailability. Particularly, estimated zinc bioavailability improved from low (Phy:Zn 25.4, Phy·Zn:Ca 295) to moderate (Phy:Zn 7.14, Phy·Zn:Ca 81.5). Phytate degradation was mainly attributed to the activation of endogenous phytase during fermentation. Dry roasting was effective in improving the sensory attributes of the fermented quinoa flour. Porridge made with raw quinoa flour fermented for 4 hr and dry‐roasted was more favorable to overall acceptability than that which was fermented for 10 hr and dry‐roasted. Conclusion: Fermentation of quinoa flour for 4 hr followed by dry roasting was successful in improving both nutritional and sensory attributes of the final product. [ABSTRACT FROM AUTHOR]

Roasting of Coffea arabica L. seeds gives rise to chemical reactions that produce more than 800 compounds, some being responsible for the desired organoleptic properties for which the beverage called "coffee" is known. In the industry, the "roasting profile," that is, the times and temperatures applied, is key to influence the composition of roasted coffee beans and the flavour of the beverage made from them. The impact of roasting on the chemical composition of coffee has been the subject of numerous studies, including by nuclear magnetic resonance (NMR) spectroscopy. However, the roasting equipment and profiles applied in these studies are often far from real industrial conditions. In this work, the effects of two critical technological parameters of the roasting process, namely, the "development time" (the period of time after the "first crack," a characteristic noise due to seed disruption) and the final roasting temperature on coffee extracts, were investigated. Seeds were roasted at pilot scale according to 13 industrial roasting profiles and extracted in D2O. The extracts were analysed by 1H NMR experiments. The NMR spectra were compared using (a) quantitative analysis of main signals by successive orders of magnitude and (b) chemometric tools (principal component analysis, partial least squares and sparse‐orthogonal partial least squares analysis). This allowed to identify compounds, which may serve as markers of roasting and showed that changes in chemical composition can be detected even for slight change in final temperature (~1°C) or in total roasting time (~25 s). [ABSTRACT FROM AUTHOR]

Summary: The effect of roasting (microwave and oven) on functional properties of garden cress (GC) (Lepidium sativum) seed flour, oil yield and fatty acid composition, colour, melting and crystallisation of oil were investigated. The obtained results revealed that roasting significantly influenced the physicochemical properties of the flour, and doubled the oil yield. The GC oil was rich in α‐linolenic acid (31.05%) and oleic acid (22.1%) along with the presence of other fatty acids including linoleic acid, erucic, stearic and arachidic acid. No significant difference in MUFA content and the U/S fatty acid ratio of GC oil was observed due to roasting. The oil sample exhibited two distinct endothermic melting transitions (≈ −35 °C and −19 °C) and one crystallisation peak (≈ −54 °C), those peaks were unaffected by the roasting. These observations were confirmed by FTIR spectroscopy. Therefore, roasting pretreatment is a promising technique to improve GC oil yield while preserving oil quality. Preparation and characterization of Garden Cress Seed flour and its oil. [ABSTRACT FROM AUTHOR]

Summary: The effects of roasting treatment on sensory quality and related compounds in green tea were investigated. The combined application of roasting temperature and time 100 °C for 90 min, 120 °C for 60 min and 140 °C for 30 min achieved the most satisfying sensory quality. The HPLC analysis showed that the contents of cis‐catechins, bitter and umami amino acids reduced with increase in temperature, while the contents of trans‐catechins and soluble sugar increased with the temperature rise. The content of caffeine and sweet amino acids did not change significantly compared with untreated tea sample. The decrease in cis‐catechins, total polyphenols and bitter amino acids reduced the bitterness and astringency of the green tea, while the increase in total soluble sugars improved the sweetness and mellow taste. The sensory evaluation results showed that the sensory quality of the tea was significantly enhanced through roasting treatment. Roasting treatment significantly improved the sensory quality of green tea. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: For the processing industry, it is crucial to know what effect the roasting process and conditions have on hazelnut quality. The present study investigates, for the first time, the effects of hot‐air and infrared (IR) roasting at different time–temperature combinations on Tonda Gentile Trilobata hazelnut: whole kernels and derived processing products (paste and oil). RESULTS: The nutritional and physical characteristics of hazelnuts and processing products were investigated to determine the influence of the different roasting conditions as a function of intended use. The antioxidant profile (2.2‐diphenyl‐1‐picrylhydrazyl radical, oxygen radical absorbance capacity and total phenolic content) were analyzed on roasted hazelnut and paste extracts. For a comprehensive understanding of the complex biochemical phenomena occurring during roasting, E‐nose and near‐IR spectroscopy were also applied. All analytical data were processed using univariate and multivariate data analyses. Hazelnuts derived from IR roasting at higher temperatures (195 °C) showed a richer antioxidant profile and a more intense flavour. On the other hand, the yield associated with the oil extraction under the same conditions was unsatisfactory, making this process completely inadequate for oil production. Oil obtained by hot‐air roasting and IR roasting at lower temperature (135 °C) was found to be of good quality, showing rather similar acidity grade, peroxide number and acidic composition. In particular, a slightly but significantly lower acidity was related to lower roasting temperatures (0.21–0.22% versus 0.27% for higher temperatures). All roasting conditions tested allowed the quantitative homogeneous hazelnut paste to be obtained and, from a rheological point of view, a higher roasting temperatures resulted in pastes characterized by higher density and viscosity values. CONCLUSION: The use of IR was found to be a promising alternative method for hazelnut roasting, as a result of its capability with respect to preserving nutritional values and enhancing organoleptic quality. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: The production and consumption of coffee are increasing despite the roadblocks to its agriculture and global trade. The unique, refreshing, and stimulating final cupping quality of coffee is the only reason for this rising production and consumption. Coffee quality is a multifaceted trait and is inevitably influenced by the way it is successively processed after harvesting. Reportedly, 60% of the quality attributes of coffee are governed by postharvest processing. The current review elaborates and establishes for the first time the relationship between different methods of postharvest processing of coffee and its varying organoleptic and sensory quality attributes. In view of the proven significance of each processing step, this review has been subdivided into three sections, secondary processing, primary processing, and postprocessing variables. Secondary processing addresses the immediate processing steps on the farm after harvest and storage before roasting. The primary processing section adheres specifically to roasting, grinding and brewing/extraction, topics which have been technically addressed more than any others in the literature and by industry. The postprocessing attribute section deals generally with interaction of the consumer with products of different visual appearance. Finally, there are still some bottlenecks which need to be addressed, not only to completely understand the relationship of varying postharvest processing methods with varying in‐cup quality attributes, but also to devise the next generation of coffee processing technologies. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: The effect of marinating beef in acid whey on the antioxidant peptides generated, and their influence on lipid oxidation, colour stability, sensory analysis and protein degradation products in uncured roasted beef stored 6 weeks in vacuum conditions (T = 4 °C) were determined. Measurements of pHe, water activity, oxidation–reduction potential, colour, TBARS, the cutting force, texture and amino acid profile, the total content of peptides, and antioxidant activity of isolated peptides were conducted immediately after production and during 42 days of storage. RESULTS: The non‐nitrite control batch (C) was characterized by a lower a* value (6.33–6.70) during the whole storage period compared to the non‐nitrite sample with acid whey (W). It also appears that meat with the worst colour stability has the poorest oxidative stability (C = 1.57 mg MDA kg−1, W = 0.76 mg MDA kg−1). Activity against reactive forms of oxygen to fraction A and fraction B (P < 0.05) showed an increasing trend with time and it was the largest in sample C and W. CONCLUSION: The results indicated that bioactive peptides could be generated in uncured roasted beef. The <3.5 kDa peptides have strong antioxidant activity, as a result of which they function as inhibitors of lipid oxidation and colour discoloration during prolonged storage. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The effect of roasting on the chemical composition and oxidative stability of oils extracted from argan (Argania spinosa L. Skeels) kernel is studied, observing changes in the characteristics of oils from unroasted and roasted kernels. Argan kernels are roasted at different temperatures (150, 175, and 200 °C) and times (10, 30, and 50 min), in an electric air roaster, prior to oil extraction using the Abencor system. Phosphorus content (PC) of oils increases significantly when roasting temperature and time increases. Roasting facilitates the transfer of phenolic compounds to argan oil. However, only minor changes in characteristics such as peroxide value and carotenoid content of argan oils occurs when roasting temperature and time are raised. The amount of γ‐tocopherol still remains over 85% of the total tocopherols after roasting at the harshest conditions (200 °C, 50 min). However, the content of each tocopherol (α, γ, and δ) gradually decreases when roasting temperature and time increases, certainly due to their thermal degradation. The oxidative stability of argan oil improves when the roasting temperature and time rise. Simultaneously, significant augmentations (p < 0.05) are observed in the specific extinction coefficients in oils prepared at high roasting temperature. The color intensity of oils increases markedly over 175 °C roasting temperature. Practical Applications: This research shows the importance of roasting for producing edible argan oils since its composition, quality and stability are influenced by the conditions of this process. Energy transfer by convection avoids the direct heat of the flame onto the argan kernel and allows the possibility that less polycyclic aromatic hydrocarbons (PAHs) are formed. Furthermore, roasting parameters (temperature and time) should be quantitatively controlled to obtain a desired quality of edible argan oils. These results may help to improve roasting processing for edible argan oil extraction. The effect of roasting temperature and time has been studied with a view to obtain oils of high quality in relation to their physicochemical properties. In the extraction process of edible argan oil, the kernel roasting is the key step that improves the quality and stability of the product. [ABSTRACT FROM AUTHOR]

Abstract: The adductor muscle of the pen shell Atrina pectinata (AMPS) is a popular protein‐enriched food item in Asian Pacific countries, and has only been marketed in the frozen condition, as a result browning and decreased sensory attributes occur. To overcome these problems, superheated steam roasting (at 270°C for 4 min) combined with the hot smoke (10 min) using a selective Oak sawdust was employed to develop a new AMPS product yielding high physicochemical properties during storage periods (0–13 days) especially at 10°C. The processed AMPS showed high sensory preferences because of good odor, color, and textural properties. It also significantly inhibited bacterial growth, volatile basic nitrogen, thiobarbituric acid‐reactive species, and pH changes, and eventually possessed higher nutritional composition with low trimethylamine N‐oxide level. Results indicate that saturated steam allows AMPS at good physicochemical conditions, whereas hot smoke‐derived aroma compounds prolong its shelf life through antioxidant and antimicrobial activities. [ABSTRACT FROM AUTHOR]

Rationale: The major objective of this exploratory study was to implement selected ion flow tube mass spectrometry, SIFT‐MS, as a method for the on‐line quantification of the volatile organic compounds, VOCs, in the headspace of the ground roasted coffee. Methods: The optimal precursor ions and characteristic analyte ions were selected for real‐time SIFT‐MS quantification of those VOCs that are the most abundant in the headspace or known to contribute to aroma. NO+ reagent ion reactions were exploited for most of the VOC analyses. VOC identifications were confirmed using gas chromatography/mass spectrometry, GC/MS, coupled with solid‐phase microextraction, SPME. Results: Thirty‐one VOCs were quantified, including several alcohols, aldehydes, ketones, carboxylic acids, esters and some heterocyclic compounds. Variations in the concentrations of each VOC in the seven regional coffees were typically less than a factor of 2, yet concentrations patterns characteristic of the different regional coffees were revealed by heat map and principal component analyses. The coefficient of variation in the concentrations across the seven coffees was typically below 24% except for furfural, furan, methylfuran and guaiacol. Conclusions: The SIFT‐MS analytical method can be used to quantify in real time the most important odoriferous VOCs in ground coffee headspace to sufficient precision to reveal some differences in concentration patterns for coffee produced in different countries. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Walnut oil extraction by pressure systems produces a press cake as a by‐product, with many of the beneficial walnut properties. The objective of this work was to evaluate the composition and antioxidant properties of walnut flours submitted to different roasting protocols (50, 100 and 150 °C during 30, 60 and 120 min). RESULTS: All walnut flours had about 42% protein and a significant amount of dietary fibre (17%), not being affected by the roasting process. Nonetheless, the fat content increased around 50% in walnuts flours subjected to longer and higher roasting temperatures (150 °C). The lipid fraction showed a good nutritional quality with a high vitamin E content (mainly γ‐tocopherol) and fatty acid profile rich in linoleic and linolenic acids. The high phenolic content also provides great antioxidant capacity to the flours. CONCLUSION: Mild roasting of walnuts did not affect the quality of the flours that could be used as a functional ingredient in the food industry. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: Cashew nut roasting before shelling is an important treatment since this roasting operation helps to shell the nuts to extract the kernels easily without damaging the edible kernels. For large scale processing, mechanized/semi‐mechanized roasters are available, but for low capacity processors, getting an economical and low capacity roaster is a challenge. For low‐capacity processing, processors opt for open pan/flame roasting method, which causes over roasting (burnt) or under roasting of cashew nuts. The aim of this article was to design and fabricate a low‐cost, simple to operate mini cashew nut roaster, which would be applicable for small scale cashew nut processors. A drum roaster was designed and fabricated, on which the experimental trials were conducted by varying the roasting time between 1 and 7 min to determine the best roasting time, where the drum roaster surface temperature was 275 ± 25 °C. From the roasting trials, it was found that fabricated cashew nut roaster was suitable for roasting cashew nuts within 2.5 min. It was low in cost and required no skilled labors for its operation. Sensory analysis of cashew nut, roasted by developed mini cashew nut roaster was found to be acceptable. The developed small capacity roaster was found suitable to address the needs of small‐scale cashew nut processors. Practical applications: The developed roaster was found suitable for roasting cashew nuts for small capacity processing. Based on the design provided in the paper, one could fabricate the roaster in any mechanical workshop having basic tools and welding facility. [ABSTRACT FROM AUTHOR]

Traditionally, pumpkin seed oil is obtained by pressing the seeds after a roasting pretreatment, at temperatures up to 150 °C. However, the appropriate temperatures and roasting times are under discussion. In this study, oils from seeds roasted at different temperatures (60-150 °C) are compared with oil from non-roasted seeds. At higher roasting temperatures, lower roasting times are required to release the oil. Both, for tocopherols and phenolic compounds, no decreasing trend with the increasing roasting temperature are observed. In contrast, the oil from non-roasted seeds have relatively low levels of tocopherols and phenolics and lacked the typical aroma. Levels of polyaromatic hydrocarbons (PAHs) are very low, ranging from not detected in oil from non-roasted seeds to 13.8 μg kg−1 in the oil from seeds roasted at 150 °C. Therefore, the choice between the studied roasting conditions may depend rather on sensory evaluations than on the content of antioxidants or of PAHs. Practical Applications: The process of the production of virgin pumpkin oil is based on a thermal treatment of the ground seeds, favoring the separation of the lipid fraction, and giving a typical aroma of the roasted oil. Results of this research provide important information regarding the influence of roasting conditions on the quality and safety of the oil. Roasting pumpkin seeds increased the tocopherol and phenols content in the pumpkin oil, with no significant formation of PAHs. The information will be valuable and important for not only for the pumpkin oil production, but also for all the seeds submitted to a roasting treatment before extraction. Pumpkin seed oil is traditionally produced in several European countries and commonly used in salad dressing. The production of pumpkin seed oil frequently includes roasting of the seeds at high temperatures, which may influence the amount of phenolic compounds and the final nutritional quality of the oil. The roasting of the pumpkin seeds is necessary to obtain the desired color, flavor, and taste characteristics. At higher roasting temperatures, lower roasting times are required to release the oil. Both, for tocopherols and phenolic compounds, no decreasing trend with the increasing roasting temperature is observed. [ABSTRACT FROM AUTHOR]

BACKGROUND The aroma of palm kernel oil ( PKO) affects its applications. Little information is available on how enzymatic modification of palm kernels ( PK) affects PK and PKO aroma after kernel roasting. RESULTS Celluclast (cellulase) pretreatment of PK resulted in a 2.4-fold increment in the concentration of soluble sugars, with glucose being increased by 6.0-fold. Higher levels of 1.7-, 1.8- and 1.9-fold of O-heterocyclic volatile compounds were found in the treated PK after roasting at 180 °C for 8, 14 and 20 min respectively relative to the corresponding control, with furfural, 5-methyl-2-furancarboxaldehyde, 2-furanmethanol and maltol in particularly higher amounts. Volatile differences between PKOs from control and treated PK were also found, though less obvious owing to the aqueous extraction process. Principal component analysis based on aroma-active compounds revealed that upon the proceeding of roasting, the differentiation between control and treated PK was enlarged while that of corresponding PKOs was less clear-cut. Celluclast pretreatment enabled the medium roasted PK to impart more nutty, roasty and caramelic odor and the corresponding PKO to impart more caramelic but less roasty and burnt notes. CONCLUSION Celluclast pretreatment of PK followed by roasting may be a promising new way of improving PKO aroma. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Brazil is the largest producer and exporter of coffee in the world, one of the main global commodities. During the processing of coffee beans, rotary drums are used in the drying and roasting phases. This equipment is widely used in many industrial sectors. According to characteristics of the drum, particulate material, and operating conditions, different flow regimes may arise. Such regimes have a direct influence on the performance of these processes and therefore their characterization is of great importance. The present work developed an experimental study about the dynamics of coffee beans, under green and roasted conditions, in a rotary drum. Transitions between rolling, cascading, cataracting, and centrifuging regimes were evaluated, for both green and roasted coffee beans. For the centrifuging regime, a comparison between experimental critical rotation speeds and the ones obtained by correlations found in literature was performed. Additionally, a new expression to predict the centrifuging rotation speed was proposed by the authors. Further analyses regarding the rolling regime were also carried out. For this regime, velocity profiles of the particles were evaluated, as well as the thickness of the active layer for different filling degrees and drum rotation speeds. Great similarity was found between the behaviour of the active region for coffee beans before and after the roasting process. [ABSTRACT FROM AUTHOR]

BACKGROUND Roasting is one of the important unit operations in the cocoa-based industries in order to develop unique flavour in products. Cocoa beans were subjected to roasting at different temperatures and times using superheated steam. The influence of roasting temperature (150-250°C) and time (10-50 min) on sugars, free amino acids and volatile flavouring compounds were investigated. RESULTS The concentration of total reducing sugars was reduced by up to 64.61, 77.22 and 82.52% with increased roasting temperature at 150, 200 and 250°C for 50 min, respectively. The hydrophobic amino acids were reduced up to 29.21, 36.41 and 48.87% with increased roasting temperature at 150, 200 and 250°C for 50 min, respectively. A number of pyrazines, esters, aldehydes, alcohols, ketones, carboxyl acids and hydrocarbons were detected in all the samples at different concentration range. Formation of the most flavour active compounds, pyrazines, were the highest concentration (2.96 mg kg−1) at 200°C for 10 min. CONCLUSION The superheated steam roasting method achieves the optimum roasting condition within a short duration Therefore, the quality of cocoa beans can be improved using superheated steam during the roasting process. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The purpose of the present study was to extend knowledge concerning the effect of rapeseeds pre-processing methods on the changes in oxidative state, alterations within fatty acids contents, and color of oil. Thermal pre-treatment of non-hulled and hulled rapeseeds by microwave radiation (2-10 min, 800 W, 2450 MHz) was studied in comparison with conventional roasting (20-100 min, 165°C). As rapeseeds were thermally pre-treated, with longer time a significant increase ( p < 0.05) in the amounts of total carotenoids, chlorophylls, and phenolics in the oils pressed from microwaved and roasted seeds was found. Oils pressed from hulled seeds (HRO) were characterized by significantly lighter yellow hue than non-hulled (NHRO) ones; however, the microwaving and roasting time significantly affected color change of both types of oils. Although induction period increased with longer seeds microwaving and roasting, oils pressed from thermally pre-treated seeds exhibited higher level of primary and secondary oxidation. Additionally, prolonged seeds heating resulted in unsaturated fatty acids degradation as detected by GC-FID. Based on the results obtained by applying principal component analysis (PCA), it can be concluded that within much shorter rapeseed exposition to microwaves similar compositional changes and degree of oxidation of oils was achieved as during conventional roasting. Practical applications:Color of edible oil is an important commercial parameter, whereas oxidative stability need to be monitored to ensure high quality of the finished product. Thermal pre-treatment is currently being used in oilseeds pre-processing, but very little researches studied its effect on color change and oxidative state of oil. Although rapeseed thermal pre-treatment can cause a number of positive quality changes, such as an increase of bioactive compounds, the results should be interpreted with caution since application of too harsh heating conditions may result in unsaturated fatty acids degradation, lipid oxidation, or undesirable color change. Thermal pre-treatment is currently being used in oilseeds pre-processing, but very little researches studied its effect on color change and oxidative state of oil. Although rapeseed thermal pre-treatment can cause a number of positive quality changes, such as an increase of bioactive compounds, the results should be interpreted with caution since application of too harsh heating conditions may result in unsaturated fatty acids degradation, lipid oxidation, or undesirable color change. [ABSTRACT FROM AUTHOR]

This study was carried out to produce high-quality weaning food from locally available and low cost raw materials. Extrudates of maize ( Zea mays) and chickpea ( Cicer arietinum) were processed by twin-screw extruder. Experiments were designed using central composite rotatable design (CCRD) with three-independent variables [feed moisture (14-18%), screw speed (400-550 rpm), barrel temperature (125-175°C)] and five-dependent variables [specific mechanical energy (SME), bulk density (BD), water absorption index (WAI), water solubility index (WSI), degree of gelatinization (DG)]. Increase in feed moisture reduced SME, WSI, and DG and increased BD and WAI. Increase in screw speed and barrel temperature decreased BD and WAI and increased WSI and DG of the extrudates. Optimum extrusion conditions were 14.13% feed moisture, 534 rpm screw speed, and 167°C barrel temperature. The ratio of ingredients in the optimized weaning mix was 40% maize-chickpea extrudates, 35% skim milk powder, and 25% sugar (w/w). The nutrient content was in agreement with the standards described by PFA (prevention of food adulteration act and rules, India, 2004) with high protein and starch digestibility. Practical applications Development of weaning foods from locally available and low cost raw materials is a constant challenge for developing countries. Weaning foods are generally produced by traditional techniques like milling, roasting, drying, and germination. In the present scenario of convenience and newer products, we explored the possibility of using twin-screw extruder for preparation of weaning foods from maize and chickpea. Effects of feed moisture, barrel temperature, and screw speed on the quality parameters of extrudates were studied. Extrudates produced at lower feed moisture, higher screw speed, and higher barrel temperature showed good physicochemical properties and higher protein and starch digestibility. [ABSTRACT FROM AUTHOR]

Traditional roasting of cassava mash into gari continues to be an arduous and intricate unit operation for processors. It is highly labor intensive, tedious, unhygienic, and productivity is often too low to justify labor and investment time. The aim of this study was thus to design and fabricate a gari roaster and evaluate its performance. Cassava mash of different moisture contents (36.21, 39.44, and 43.27%) were roasted at different garifying temperatures (75, 85, and 95°C) and performance characteristics including, roasting time, percentage material loss, functional efficiency, throughput, and machine capacity were evaluated. Results obtained indicated that roasting cassava mash of 39.44% at 85°C yielded the best roasting conditions, as it had the least material loss of 7.8%, best throughput capacity and functional efficiency of 34.66 kg/hr and 92.20%, respectively. The fabricated gari roaster does not require skilled labor and can effectively address the challenges associated with gari roasting. Practical Application The fabricated roaster is relevant to the roasting of cassava mash to produce gari. This will practically address the impending challenges associated with gari roasting especially in the rural areas. This roaster will further ensure production of quality gari to its teeming consumers, thereby contributing to food security. [ABSTRACT FROM AUTHOR]

The kinetics of color development during peanut roasting were investigated at roasting temperatures from 149 to 204°C which produced Hunter L color values of 25-65. Preliminary and equivalent roasting trials were conducted using a batch roaster simulating the parameters of an industrial continuous belt roaster. Hunter L and b values of the roasted peanuts were fitted well to first-order models (mean R2 > 0.93). The activation energy calculated from the first-order model of the L and b values ranged from 1.0 to 1.1 × 108 J/kg mol. High-temperature roasting decreased the uniformity of color development from seed to seed and throughout of the kernel. A zc value of 37.6°C was calculated using the first-order model of the L values. The cook values were 11.5-23.6, 24.5-31.6, and 41.5-57.5 min for light, medium, and dark roasting, respectively. [ABSTRACT FROM AUTHOR]

Cocoa beans are widely used in the manufacturing of various food and beverage products such as chocolates, powdered drink, cookies, confectioneries, and others. Processing plays a vital role in governing the final flavor profile of cocoa beans especially during roasting. The current studies aimed to determine the transport properties of cocoa nibs during roasting and also to investigate the quality of roasted cocoa nibs. Cocoa nibs were roasted at temperatures of 120, 130, and 140 °C inside a hot air convective oven. Kinetics analyses showed that overall rates of sensible heating (from T = 27 to 100 °C) were in the range of 5.1-9.5 °C/min as compared to overall rates of effective roasting (from T = 100 °C onwards) in the range of 0.9-1.4 °C/min. The observed moisture content profiles followed the typical exponential decay as commonly explained by the Fick's second law of diffusion. The dependency of thermal and moisture diffusivities with temperatures could be described using quadratic and Arrhenius models, respectively. It was determined that the average order of magnitude for moisture diffusivity was 10−10 m2/s as compared to 10−9 m2/s for thermal diffusivity. High roasting temperature had a negative impact on cocoa polyphenols where greater degradation was observed. Sensory evaluation showed that cocoa liquor produced from the higher temperature treatment ( T = 140 °C) had the highest cocoa flavor. Practical applications Information on the roasting kinetics and moisture/thermal diffusivities are important design parameters for cocoa roaster. Changes in flavor quality during roasting are important in governing the development of flavor in the finished chocolate products. Therefore, the current studies contribute knowledge to the cocoa industry for both equipment and chocolate manufacturers. [ABSTRACT FROM AUTHOR]

Kabuli chickpea seeds were processed by soaking only and soaking followed either by pressure cooking or roasting. Proteins were isolated from both raw and processed seeds, and the effects of these processing approaches on the physicochemical, functional, thermal and structural properties as well as SDS- PAGE profiles of the protein isolates were investigated. Thermal processes significantly ( P < 0.05) decreased protein yield, content, colour difference, emulsifying properties and protein solubility of the protein isolates, but increased lightness and water and oil absorption capacities. Protein thermal properties, secondary structure and SDS- PAGE banding patterns were significantly changed in thermal-processed samples, especially those that were pressure cooked. No endothermic peak was detected in differential scanning calorimetry thermograms, and peak intensity of amide I absorption band at 1600-1700 cm−1 in Fourier transform infrared spectra reduced. The results reveal that pressure cooking had more pronounced effects on the properties of the protein isolates than other processing approaches. [ABSTRACT FROM AUTHOR]

In this work, the decomposition characteristics of compound additive (NaCl and Na2SO4) were investigated by thermogravimetry-differential scanning calorimetry-mass spectrometry coupling techniques. The results showed that the decomposition of NaCl was prior to that of Na2SO4 and the chlorine was generated during roasting. When the chlorine concentration is more than 2%, the phenomenon of vanadium volatilization becomes obvious in the process of roasting of stone coal. However, the chlorine concentration is less than 50 p.p.m. for the compound additive roasting, which would not cause the vanadium emission. The oxygen concentration of more than 5% is sufficient for oxidizing V(III) in the stone coal to water soluble V(V). Copyright © 2017 Curtin University of Technology and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The paper looks at the levels of phenolic compounds in cold-pressed and hot-pressed rapeseed oils produced from seeds of various moisture levels (5, 7.5, and 10%). The paper also considers the effects of seed roasting on the levels of these compounds. The quality of the obtained oils is determined using the peroxide and acid values. The levels of phenolic compounds are analyzed using HPLC. It is demonstrated that the oils produced from rapeseeds with 5% moisture content, and in particular from cold-pressed oils, were characterized by the lowest peroxide values. The roasting of the seeds and their level of moisture both significantly affect the quality of the obtained oil. Oils obtained by hot-pressing the seeds with 10% moisture contained over 30% more of these compounds. The roasting process has a significant influence on the amount of phenolic compounds in the test oils. Practical applications: Depending on the environmental conditions and post-harvesting procedures, rapeseeds are characterized by varying water contents. To obtain high-quality cold-pressed or hot-pressed oil with high levels of phenolic compounds, knowledge of the effects of seed moisture content on these parameters is necessary. The paper describes the effects of moisture content, as well as of seed roasting and of the oil production methods (cold-pressing vs. hot-pressing). There is no doubt that such information will be useful for both small and large manufacturing operations that produce cold-pressed oils. The rapeseeds for pressing were prepared as roasted (160°C, 15 min) or unroasted and with different moisture levels (5, 7.5, and 10%). The oils were cold-pressed and hot-pressed. The levels of phenolic compounds in the resulting oils differed with statistical significance. A significant increase in the level of phenolic compounds in hot-pressed oils was seen, though this was also dependent on the moisture of the rapeseeds. [ABSTRACT FROM AUTHOR]

This study applies proton transfer reaction time-of-flightmass spectrometry for the rapid analysis of volatile compounds released from single coffee beans. The headspace volatile profiles of single coffee beans (Coffeea arabica) from different geographical origins (Brazil, Guatemala and Ethiopia) were analyzed via offline profiling at different stages of roasting. The effect of coffee geographical origin was reflected on volatile compound formation that was supported by one-way ANOVA. Clear origin signatures were observed in the formation of different coffee odorants. [ABSTRACT FROM AUTHOR]

Breakfast cereals were produced by roasting ( t = 280°C) - a dry heat treatment process to gelatinize and semidextrinize the starch - in order to generate dry ready-to-eat products from blends of African yam bean ( AYB), maize (M), and defatted coconut ( DC) flour. Six samples were generated by mixing AYB and maize composite flour with graded levels of DC flour (0%, 10%, 20%, 30%, 40%, and 50%) to obtain the following ratios; 100:0, 90:10, 80:20, 70:30, 60:40, and 50:50 that were added equal quantities of sugar, salt, sorghum malt extract, and water. The obtained products were served dry (without added fluid), with water, milk, and warm milk to 15 panelists along with Weetabix Original (commercial control) to evaluate color, consistency, flavor, taste, aftertaste, mouth feel, and overall acceptability using a nine-point hedonic scale (1 = dislike extremely, 9 = like extremely). The results revealed that the samples were acceptable to the panelists. There were no significant ( P > 0.05) differences, between the control (Weetabix) and the formulated samples in terms of overall acceptability, when served with water, whereas significant differences ( P < 0.05) existed when served dry, with milk or warm milk. This new roasting process for producing breakfast cereals offers huge potentials for production of acceptable breakfast cereals enriched with protein and fiber-rich sources that could be consumed dry, with water, milk, or warm milk. [ABSTRACT FROM AUTHOR]

BACKGROUND This work aimed at formulating a carob-based milk beverage and assessing its chemical and sensory properties. Six varieties of carob pods, each processed into roasted and unroasted powders, were used to develop 12 prototypes of the beverage. Chemical and physico-chemical analyses (moisture, ash, fibre, protein, sugars, total-phenolics, total-antioxidants, water activity and colour) and sensory tests were conducted. RESULTS The variety of carob pod had a significant effect on all chemical variables in carob powders ( P < 0.01), except for sugars, and when incorporated in the beverage, on moisture, total phenolics, total antioxidant activity and colour parameters ( L, a, b; P-values < 0.001). Roasting treatment significantly increased fibre, total phenolics, total antioxidant activity ( P-values < 0.001), fructose, glucose ( P-values < 0.05), and a-value levels ( P < 0.01), significantly lowered moisture ( P < 0.05), water activity, L- and b-values ( P-values < 0.001) in carob powders; and significantly increased the beverage's total phenolics, a-value ( P-values < 0.001) and total antioxidant activity ( P < 0.01). Roasting treatment significantly increased the beverage's acceptability ratings. Beverages formulated with roasted carob powder had higher ratings for level of residue, colour, caramel odour, mocha odour and flavour, roasted coffee odour and flavour, viscosity mouthfeel and bitter aftertaste. Principal component analysis was conducted; PC1 and PC2 separated attributes according to roasting treatment and variety of carob pods, respectively. CONCLUSION The use of Akkari roasted and Baladi Ikleem el Kharoob roasted to formulate a carob-based milk beverage is recommended. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Roast duck is one kind of representative roast food whose flavor is mainly produced by the Maillard reaction. However, some potentially toxic compounds are generated in the thermal process and are a potential health risk. The aim of this work was to analyze the effects of the Maillard reaction on flavor and safety of a Chinese traditional food: roast duck. RESULTS Ducks with different roasting times (0, 10, 20, 30, 40, 50 and 60 min) were analyzed. The 40 and 50 min roast ducks exhibited an acceptable degree of sensory attributes, but the 60 min roast duck showed the most abundant aroma compounds. Antioxidant activities were observed to increase with roasting, and the 60 min roast duck showed the highest antioxidant activities (1,1-diphenylpicryhydrazyl, 39.3 µmol Trolox g−1 sample). The highest content of acrylamide (0.21 µg g−1) and 5-hydroxymethylfurfural (0.089 µg g−1) were detected in the 50 and 60 min roast duck extract, respectively. Furthermore, water extract from 60 min roast ducks manifested a higher lactose dehydrogenase release ratio (51.9%) and greatly increased cell apoptosis. CONCLUSION The drastic Maillard reaction in duck induced by long roasting time could be advantageous for color, aroma and antioxidant activities in roast ducks, but might be not beneficial to health. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Roasting improves the palatability of barley grains. After processing, the resulting powder is widely used to elaborate beverages such as coffee and tea. The objective of this research was to evaluate the influence of roasting on the characteristics of barley grains and the derived powder. The kinetics of release of soluble solids during the powder hydration at 80°C, performed to produce beverages such as tea, was also determined. In addition, the influence of roasting and rehydration temperatures on the physical composition of the beverages and on the release of soluble solids was investigated. After roasting, barley was ground and sieved. The powder retained in the 0.425 mm sieve was used in the analyses. Owing to roasting, the average protein content of barley increased from 10.56 to 12.88 g/100 g, and the sugar content decreased from 730 to 12.99 mg/mL, which is ascribed to the high process temperature. The phenolic compounds increased from 105.33 to 253.07 mg of ferulic acid per milliliter between the nonprocessed sample and the one roasted at 240°C, respectively. The antioxidant activity decreased with the roasting temperature rise (160-240°C) from 11.60 to 5.30 pg of 2,2- diphenyl-1-picrylhydrazyl per milliliter. In the production of beverages such as tea, higher roasting temperatures led to a greater release of soluble solids in water. [ABSTRACT FROM AUTHOR]