Color Compounds Research Articles

Nitrogen-doped porous carbon nanomaterials synthesized using a magadiite template as efficient peroxidase mimics for colorimetric detection of ascorbic acid as an antioxidant.

Nanomaterials with intrinsic enzyme-like activity have gained substantial scientific attention as viable substitutes to natural biological enzymes owing to their cheap price and great stability. Numerous artificial enzyme mimics have been employed effectively in sectors such as sensing, environmental processing, and cancer treatment. In this study, novel nitrogen-doped porous carbon nanomaterials (CPs) were produced by modifying polypyrrole with magadiite using chemical oxidative polymerization and calcination methods. The obtained nitrogen-doped porous carbon nanomaterials exhibited improved peroxidase-like activity, which catalyzed the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (H2O2) to produce colorful compounds. Kinetic investigation revealed that the affinity for TMB of nitrogen-doped porous carbon peroxidase mimics was higher than that of genuine horseradish peroxidase (HRP). In addition, a sensitive assay with encouraging performance for the colorimetric detection of ascorbic acid (AA) was successfully fabricated employing nitrogen-doped porous carbon nanomaterials as peroxidase mimics. The results were satisfactory and demonstrated its potential application in antioxidant detection.

Comprehensive evaluation of nine grape varieties based on fundamental physical and chemical indicators, color and volatile compounds

BACKGROUND: In todays’ society, the rapid development of the wine industry and the improvement of peoples’ living standards make people pay more and more attention to wine grape quality. OBJECTIVE: To evaluate the wine grape varieties in Northeast Chinas’ grape growing regions for better wine grape quality, we evaluated the quality of different varieties of wine grapes. METHODS: The grape varieties ‘Hassan’ ‘Zuoshaner’ ‘Beibinghong’ ‘Zuoyouhong’ ‘Beta’ ‘Shuanghong’ ‘Zijingganlu’ ‘Cabernet Sauvignon’ and ‘Syrah’ were planted in the grape growing area of Jilin, Northeast China, were used as the subjects of this study. The grape berries were analyzed and tested for morphological indicators, basic physicochemical indicators, color, and phenolic and aromatic composition. RESULTS: According to lab results, ‘Hassan’ contained the highest amount of total phenolics; ‘Zuoyouhong’ had the highest solids and total sugar content; ‘Shuanghong’ had the most elevated total acid and anthocyanin content; ‘Zijngganlu’ had the highest tannin content and acid fixation ratio; Seventy-one volatile compounds were detected in nine grape varieties. CONCLUSIONS: Each of the nine grape varieties has a distinctive flavor, and because of this, grape processing products with regional flavors can be created. The same offer valuable data for future scientific grape resource collection, conservation, and exploitation.

Cultural unit blue in the Old Testament

Abstract The paper describes and analyzes the full presence of blue in the Old Testament – in Hebrew and translations. The interdisciplinary approach includes the treatment of color as a cultural unit according to of Eco’s idea, lexical and contextual semantics, distinguishing visual and verbal color languages. The interface between verbal and visual color language is the prototype. Prototypes are universal natural visual objects – sky, sea, fire, blood, the sun at noon, all plants, light, milk, snow, darkness, and coal and have evolved into cultural units (Eco 1996 [1985]) in all cultures and languages. Basic Color Terms (BCT – blue), Prototype Terms (PT – sky and sea), Rivals Terms of prototypes (RT – sapphire, blue skins), Terms for Basic Features of the Prototypes (TBFP – breadth, infinite, boundless) are examined. Translation is a criterion for semiotic value, cultural and linguistic context. Norm of Test of Free Word-Associations is a source of non-color (secondary) meanings of verbal colors. Test results allow us to flesh out the hidden links ‘prototype color─most typical feature of the prototype─secondary meanings of color’ in text and visual culture. The secondary cultural meanings of BCTs and RTs are specified in color compounds. The color blue tehèlet is used in most cases in synergy (not in opposition) with the other three colors in a tetrad: purple argamàn─scarlet tolàat shanì─linen shesh. Analysis on the synergic relations is performed. The same applies to duads blue-linen, blue-purple, blue skins-scarlet, blue skins-red skins. Color compounds are elements of the Priestly Code, therefore a hypothesis on compounds at semiotic axes is developed. The PT sky is involved in religious heritage. Themes as Hebrew substitute shamàim for the Tetragrammaton, the Hierarchy of heavens complete the areas of cultural unit blue in the Old Testament.

Effects of ohmic heat processing and ascorbic acid on antioxidant compounds and colour of red‐fleshed dragon (Hylocereus polyrhizus) fruit juice during storage

SummaryRed‐fleshed dragon fruit is a promising source of antioxidants and natural colour compounds. This study examined the effects of ohmic heating (OH) and ascorbic acid addition on total phenolic content (TPC), betacyanin (BC), antioxidant activity and colour changes in the juice during storage. The juice was treated from 20 to 85 °C and stabilised at 85 °C for 60 s by OH at 60 Hz and 30 V cm−1. The treated samples were stored at 4 °C in dark bottles for 8 weeks, and BC, TPC, antioxidant activity and colour were determined weekly. After 1 week of storage, there was no degradation of TPC or BC (P > 0.05). However, after 8 weeks of storage, BC decreased by 47%, TPC decreased by 60% and antioxidant activity decreased by 39% in the OH juice. The colour changes of the juice during the 8‐week storage period were strongly correlated with the BC (r (correlation coefficient) > 0.98). A comparison of the OH process with conventional heating (CH) showed that OH resulted in less degradation to BC, TPC and antioxidant activity than CH. OH is a suitable technology for processing red‐fleshed dragon fruit juice. Adding 0.25% AA to the juice helped reduce changes in colour, BC, TPC and antioxidant activity (P < 0.05).

Development and Characterization of Yellow Passion Fruit Peel Flour (Passiflora edulis f. flavicarpa).

In this study, the peels of the yellow passion fruit (Passiflora edulis f. flavicarpa) were used to develop a flour that was evaluated in terms of its physicochemical, microscopic, colorimetric, and granulometric characteristics, its total phenolic compound and carotenoid contents, and its antioxidant capacity. Fourier Transform Infrared (FTIR) spectroscopy measurements were employed to investigate the constituent functional groups, compounds' chemical profiles were assessed by Paper Spray Mass Spectrometry (PS-MS), and the compound's chemical profiles were evaluated by Ultra-Performance Liquid Chromatography (UPLC). This flour presented a light color, heterogeneous granulometry, high carbohydrate, carotenoid, and total phenolic compound contents with high antioxidant capacity. Scanning Electron Microscopy (SEM) showed a particulate flour, which is supposed to contribute to its compactness. FTIR demonstrated the presence of functional groups corresponding to cellulose, hemicellulose, and lignin, constituents of insoluble dietary fiber. The PS-MS analysis suggested the presence of 22 substances, covering diverse component classes such as organic, fatty, and phenolic acids, flavonoids, sugars, quinones, phenylpropanoid glycerides terpenes, and amino acids. This research demonstrated the potential of using Passion Fruit Peel Flour (PFPF) as an ingredient for food products. The advantages of using PFPF comprise the reduction of agro-industrial waste, contribution to the development of a sustainable food system, and increment of food products' functional profile. Moreover, its high content of several bioactive compounds can benefit consumers' health.

CHANGES IN BIOACTIVE COMPOUNDS IN FRUITS OF Eriobotrya japonica GROWN IN THREE DIFFERENT LOCATIONS IN NORTHEASTERN PERU

Recently, there has been a growing interest in bioactive compounds metabolized by plants, which are an important nutritional source for the human diet and are found in almost all vegetables and fruits. The objective was to evaluate the changes of bioactive compounds during the ripening of loquat (Eriobotrya japonica) fruit. For this purpose, fruits were collected at three different stages of ripening from three different production sites in the Amazon region, located in northeastern Peru. Color, total phenolic content (Folin-Ciocalteu method), antioxidant activity (DPPH free radical method) and total flavonoids (colorimetric assay) were determined for all samples. Data were subjected to analysis of variance and means were compared by Tukey’s test (p ≤ 0.05). Color and bioactive compounds depend on the stage of ripening and, to a lesser extent, on the origin of the fruit. Ripe fruits have a higher content of phenolic compounds and flavonoids (up to five times higher) that can be used in the food and pharmaceutical industry.

Effect mechanism of different drying methods on the quality and browning for daylily

The influence of various drying methods, namely hot-air drying (HAD), heat pump drying (HPD), freeze-drying (FD), and microwave freeze drying (MFD), on the structural characterization and browning substrates of daylily was investigated. The chemical structure as determined by Fourier Transform infrared spectroscopy of the products from different drying methods were similar and the microphysical structure (microstructures and texture) were significantly different. High-quality daylily products with a bright appearance and a lower degree of browning were produced by FD and MFD. Higher contents of browning substrates (phenolic acid, total flavonoids, and total phenols) were found in products with lower browning (color, browning degree and Maillard fluorescent compounds). FD products kept the highest contents of gallic acid (27.39 mg/100 g), chlorogenic acid (35.92 mg/100 g), and quercetin (15.03 mg/100 g), and had a high nitrite scavenging activity. MFD products kept the highest contents of catechin (144.90 mg/100 g), rutin (71.5 mg/100 g), and kaempferol (33.87 mg/100 g). The results showed that the final products produced by FD and MFD had superior quality than those produced with HAD and HPD. FD and MFD are suitable for daylily powder with high nutritional value and HAD and HPD are suitable for large-scale production and affordable dried daylily products.

Stability of labile xanthones and dihydrochalcones in a ready-to-drink honeybush beverage during storage.

The shelf-life of a functional herbal tea-based beverage is important not only for consumer acceptability, but also for the retention of bioactive compounds. The present study aimed to clarify the role of common iced tea beverage ingredients (citric and ascorbic acids) on the shelf-life stability of an herbal tea-based beverage. A hot water extract of green Cyclopia subternata, also used as honeybush tea, was selected as the main ingredient because it provides different types of phenolic compounds associated with bioactive properties (i.e. xanthones, benzophenones, flavanones, flavones and dihydrochalcones). The model solutions were stored for 180 and 90 days at 25 and 40 °C, respectively. Changes in their volatile profiles and color were also quantified as they contribute to product quality. 3',5'-Di-β-d-glucopyranosyl-3-hydroxyphloretin (HPDG; dihydrochalcone) and, to a lesser extent, mangiferin (xanthone), were the most labile compounds. Both compounds were thus identified as critical quality indicators to determine shelf-life. The stability-enhancing activity of the acids depended on the compound; ascorbic acid and citric acid enhanced the stability of HPDG and mangiferin, respectively. However, when considering all the major phenolic compounds, the base solution without acids was the most stable. This was also observed for the color and major volatile aroma-active compounds [α-terpineol, (E)-β-damascenone, 1-p-menthen-9-al and trans-ocimenol]. The addition of acids, added for stability and taste in ready-to-drink iced tea beverages, could thus have unwanted consequences in that they could accelerate compositional changes and shorten the shelf-life of polyphenol-rich herbal tea beverages. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Impact of solid‐state fermentation by Aspergillus niger 4Q and Cyberlindnera fabianii J2 on antioxidant and flavor properties of whole grain barley

AbstractBackground and ObjectivesAspergillus niger 4Q and Cyberlindnera fabianii J2 were isolated from a traditional Chinese sweet rice wine starter because of their better fermentation characteristics and sensory properties of final products. To understand the impacts of the cofermentation with Aspergillus niger 4Q and Cyberlindnera fabianii J2 in a solid state on the nutritional and physico‐chemical properties of whole grain barley, yellow barley and black barley were used as raw materials. Content of chemical and nutritional compositions, in vitro antioxidant activity, color, and volatile flavor compound analysis of untreated, cooked and fermented barley samples were evaluated.FindingsThe contents of total phenolic compounds, total flavonoids, and anthocyanin of black barley were 1.25 times, 1.21 times, and 2.05 times higher than those in yellow barley (p < .05). After fermentation, the proteins, water‐soluble dietary fiber, and β‐glucan contents of both black barley and yellow barley samples were about respectively 1.3 times, 4.6 times, and 1.2 times higher than those in raw materials (p < .05). Total proportion of phenolic compounds and flavonoids, along with the antioxidant capacity, free radical scavenging rate and Fe2+ chelating activity were significantly increased (p < .05). Lighter and brighter color were observed in fermented barleys which might be credit to the reduced anthocyanins. The acidic methyl esters, uniquely existed in untreated barley, were transformed into acetate esters after fermentation. Ethyl 3‐methyl‐acetate, with a fruity aroma, was the major proportion of esters in fermented barley, endued the unique flavor to fermented barley.ConclusionsSolid‐state fermentation of yellow barley and black barley by A. niger 4Q and C. fabianii J2 could effectively improve their nutritional and physico‐chemical properties.Significance and NoveltyThis study may contribute to providing a solution for improving the nutritional and sensory preterits of whole grain barley, as well as a theoretical support for promoting the direct utilization of barley in food processing.

Kinetic and thermodynamic aspects on the interaction of serum albumin with sodium hydrosulfite: Spectroscopic and molecular docking methods

Sodium hydrosulfite is a sulfur-containing food additive that is used as a decolorizing agent in the sugar industry to purify syrup and remove natural color compounds obtained from sugar beet, sugar cane, and color compounds created during production. Recent studies show gastrointestinal, aspiration, skin and eye complications from excessive use of sulfur-containing compounds. According to recent studies and the importance of investigating the interaction of food additives with biological molecules, we also investigated the binding properties of sodium hydrosulfite to blood serum albumin through UV–Vis spectroscopy, fluorescence spectroscopy, competitive binding experiments, Fourier transform infrared spectrometry (FT-IR), surface plasmon resonance (SPR), and molecular simulation analysis. According to the results, Sodium hydrosulfite decreased the fluorescence intensity of BSA through both static and dynamic quenching mechanisms after forming a complex with BSA. The results of synchronous fluorescence and FT-IR demonstrated that the microenvironment and the secondary structure of BSA were changed in the presence of sodium hydrosulfite. The negative values of ΔH° and ΔS° indicated that van der Waals force or hydrogen bonding is the main factor of binding between sodium hydrosulfite and BSA. The result of UV–Vis spectroscopy confirmed the binding of sodium hydrosulfite to BSA. Binding constant decreases from 13.06 to 0.24 (103 M−1) with increasing temperature, which indicates a decrease in complex formation owing to the interaction of sodium hydrosulfite with BSA. Molecular docking experiments confirm the binding tendency of sodium hydrosulfite to a cavity between domains II and III (Site I and Site II) through residues Cys460, Cys476, Asn457, Arg483, Lys204, and Ala200 with a binding energy of −12.86 kJ mol−1.

Finding the Stability Constants for the Colored Compounds Resulting from The Reaction of Five Food Dyes with the Diazotized Para-Nitro Aniline Reagent at their Natural pH

Finding the Stability Constants for the Colored Compounds Resulting from The Reaction of Five Food Dyes with the Diazotized Para-Nitro Aniline Reagent at their Natural pH

A photoperiod including visible spectrum LEDs increased sulforaphane in fresh-cut broccoli

The objective was to elucidate if a photoperiod including fluorescent light (14 h) and visible spectrum LEDs (10 h), during night periods, can increase the phytochemical content in fresh-cut broccoli while not affecting other quality attributes. Monochromatic LEDs used were Cool White -CW-, Blue -B-, Green -G-, Red -R-, and Far-Red -FR-, while darkness was used as control. Changes in weight losses, colour, epiphytic microorganisms, and main bioactive compounds (glucosinolates and isothiocyanates) were assessed during 16 days at 5 ºC. Illumination with G and R lights accelerated yellowing of florets after 14 days. Higher weight losses were registered for LEDs treatments regarding darkness while no changes were observed for microbial development among treatments. All studied photoperiods including LEDs enhanced the sulforaphane content regarding darkness, especially after 7 days, reporting CW, B, and FR treatments increases over 40%. However, the glucosinolate content and myrosinase activity were not stimulated by LEDs. In conclusion, a supplementation with CW, B, or FR LEDs during night periods at retail sale seems a strategy to enhance the sulforaphane accumulation in Brassicaceae. Probably, higher and / or other stresses can be applied to increase / activate the synthesis and accumulation of more secondary metabolites.

Optimization of Caviar-Like Hydrogel Beads Containing Melanin-Free Cuttlefish Ink: Physicochemical Characterization

ABSTRACT MFI was extracted from cuttlefish (Sepia officinalis) and used as a colorant, flavoring, and bioactive compound in caviar-like hydrogel beads. The production parameters, including alginate, salt (NaCl), MFI concentration, and pH, were optimized using response surface methodology. The physicochemical properties of beads produced at optimum conditions (NaCl: 2%, alginate: 1.25%, pH: 8.12, and MFI: 1.39%) were compared with commercial lumpfish (Cyclopterus lumpus) caviar. The analyses showed no significant difference between caviar-like beads and commercial lumpfish caviar. These results suggest that caviar-like beads produced under optimum conditions can be commercialized at low cost to provide an opportunity for sustainable aquaculture.

Optimization of extraction, characterization, and stability of the natural pigment from sorghum genotype SC 319

Darker pericarp sorghum genotypes have high levels of anthocyanins: natural pigments that have antioxidant potential and may serve as a natural alternative dye to replace synthetic colorants. Thus, the objective of this work was to obtain a powder dye from sorghum pericarp genotype SC 319, quantifier total phenolic compounds, total anthocyanins, and color. In addition, evaluate the stability during storage at room temperature for 30 days and test an application in gelatin gummies. There was no significant difference for total phenolic compounds during all days of storage, with values ​​between 36.80 and 37.97 mg GAE.g-1. For total anthocyanins, despite the variation in levels during storage, the values ​​obtained on the first day (2.407 mg Eq. Lut.g-1) and on the last day (2.379 mg Eq. Lut.g-1) did not differ. There was a significant difference in all colorimetric axes and the reddish hue increased during storage, ranging from 7.04 to 9.11. For the gelatin gummies, compared to the powder dye, the anthocyanins and phenolic contents were lower, but the red hue presented a high value (28.9). Therefore, it was possible to obtain a stable powder natural dye from sorghum pericarp that can provide color and bioactive compounds to foods.

The effect of different technologies in Pomegranate jam preparation on the phenolic compounds, vitamin C and antioxidant activity

The effect of different gelling agents and processing for jam production from pomegranate juice was evaluated. In the last years, different gelling agents were tested for improving jam quality in terms of color and bioactive compounds. The unsonicated and sonicated pomegranate juices were processed for jam production by microwaves, under vacuum and cryoconcentration concentration methods using low and high methoxy pectins, and carob seed flour as gelling agents. The polyphenols content of sonicated jam was significantly lower than unsonicated samples and cryoconcentrated jams showed the significantly highest value among other methods. The results showed the highest anthocyanin content in the both sonicated and unsonicated jam including carob seed flour and antocyanins content of the cryoconcentrated samples was in the range of 156.6–186.2 mg/kg, and revealed higher content compared to the other processed samples.The findings showed that cryoconcentrated method is more effective in preserving the total polyphenols, anthocyanins, vitamin C and antioxidant activity. Moreover, also the colour of cryoconcentrated pomegranade jam was preserved. Cryoconcentration is a promising method for preserving organoleptic and functional properties of the jam produced from pomegranate juice.

Performance of UV-LED and UV-C treatments for the inactivation of Escherichia coli ATCC 25922 in food model solutions: Influence of optical and physical sample characteristics

Shortwave ultraviolet light (UV-C) and ultraviolet light-emitting diodes (UV-LEDs) are emergent technologies to inactivate pathogenic and spoilage microorganisms in food. However, the effectiveness of these technologies is influenced by the optical properties of the treated food. This work aimed to evaluate the effect of the optical properties of nine model food solutions on the efficacy of UV-C (at 255 nm) and UV-LEDs (at 255, 265 or 280 nm) to inactivate E. coli ATCC 25922. Model solutions were formulated with saccharose (SC), tartrazine (TT) and xanthan gum (XG), exposed from 0 to 50 min. The microbial population was reduced after 15 min of UV-C and UV-LED treatment by >6 log CFU/mL for water and TT, and by UV-C for SC, XG, TT + SC, and (XG + TT + SC) m solutions. The inactivation data were correlated using three different models. Colored compound (TT) showed 60% degradation by UV-C compared to 3% by UV-LED at 50 min. Industrial relevanceNon-thermal treatments such as those based on ultraviolet light, UV-C, and UV-LEDs could have high industrial relevance because of their simplicity of operation and reduced by-product formation, being a friendly alternative for food processing. Understanding the effect of different optical and physicochemical properties of liquid food to be treated by UV-based technologies is mandatory for the equipment's efficient design and operation. Furthermore, the proper selection of processing conditions, such as delivered dose and processing time, allows for obtaining safe and high-quality products.

Multidisciplinary evaluation of plant growth promoting rhizobacteria on soil microbiome and strawberry quality

The natural soil environment is considered one of the most diverse habitats containing numerous bacteria, fungi, and larger organisms such as nematodes, insects, or rodents. Rhizosphere bacteria play vital roles in plant nutrition and the growth promotion of their host plant. The aim of this study was to evaluate the effects of three plant growth-promoting rhizobacteria (PGPR), Bacillus subtilis, Bacillus amyloliquefaciens, and Pseudomonas monteilii for their potential role as a biofertilizer. The effect of the PGPR was examined at a commercial strawberry farm in Dayton, Oregon. The PGPR were applied to the soil of the strawberry (Fragaria × ananassa cultivar Hood) plants in two different concentrations of PGPR, T1 (0.24% PGPR) and T2 (0.48% PGPR), and C (no PGPR). A total of 450 samples from August 2020 to May 2021 were collected, and microbiome sequencing based on the V4 region of the 16S rRNA gene was conducted. The strawberry quality was measured by sensory evaluation, total acidity (TA), total soluble solids (TSS), color (lightness and chroma), and volatile compounds. Application of the PGPR significantly increased the populations of Bacillus and Pseudomonas and promoted the growth of nitrogen-fixing bacteria. The TSS and color evaluation showed that the PGPR presumptively behaved as a ripening enhancer. The PGPR contributed to the production of fruit-related volatile compounds, while the sensory evaluation did not show significant differences among the three groups. The major finding of this study suggests that the consortium of the three PGPR have a potential role as a biofertilizer by supporting the growth of other microorganisms (nitrogen-fixing bacteria) as part of a synergetic effect and strawberry quality such as sweetness and volatile compounds.

Comprehensive anthocyanin and flavonol profiling and fruit surface color of 20 blueberry genotypes during postharvest storage

Blueberry surface color is determined in large part by anthocyanin pigments and is one of the most important quality traits influencing consumer preference. Postharvest changes in fruit surface color and phenolic compounds, including anthocyanins, have been reported in blueberries; however, the relationships between these changes had not yet been investigated. A total of 25 anthocyanins and 14 flavonols were quantified across 20 blueberry genotypes at harvest and during four weeks of postharvest storage in 2019 and 2020. Total anthocyanin concentration ranged from 585.4 to 2556.4 mg kg‐1 across genotypes and was higher than total flavonol concentration that ranged from 129.3 to 331.0 mg kg‐1. Malvidin glycosides were the major anthocyanins in all genotypes; however, distinct anthocyanin profiles were observed among genotypes based on differences in the type of glycosylation. Quercetin 3-O-galactoside was the most abundant flavonol in all genotypes. Changes in total anthocyanin and total flavonol concentrations showed various trends during storage, depending on the genotype and the season. In contrast, anthocyanin and flavonol profiles for each genotype remained constant during storage and between seasons. Surface color parameters (lightness, chroma, and hue angle) showed weak correlations (r < 0.4) with anthocyanin concentrations measured at harvest and during postharvest storage. However, the color changes (Δ color) over four weeks of storage showed a strong correlation (r > 0.7) with changes in anthocyanin concentrations. This study provides novel understanding of the relationship between changes in anthocyanins and fruit surface color during postharvest storage in blueberries.

Investigation of Color and Bioactive Compounds of Different Colors from Pansy (Viola × wittrockiana Gams.) Dried in Hot Air Dryer

The popularity of edible flowers is increasing day by day and new solutions are sought due to their short shelf life. For this purpose, in this study, four different colors of Viola × wittrockiana Gams.; white (Fino Clear White), orange (Delta Pure Orange), bordeaux/mauve rose (Mammoth Rocky Rose), and yellow (Delta Premium Pure Lemon) flowers were dried at drying air temperature of 60, 70, and 80 °C with a convective hot air dryer. Color (L*, a*, b*, C*, h°, ∆E, and BI), drying time and bioactive compounds (Total Phenolic Content (TPC), anthocyanin content (AC), and antioxidant activity (AO) values were measured). The orange flowers showed the fastest drying (78 min at 80 °C). The lowest total color change (∆E) (4.58 at 70 °C) and browning index (BI) (9.58 at 60 °C) values were observed in all drying processes of white flowers. The highest AC was determined in bordeaux flowers in both fresh (2.4 mg malvidin glucoside/g) and dried (25.57 mg malvidin glucoside/g at 60 °C) samples. The AO decreased in all samples depending on the temperature increase, it was found that the most beneficial result in terms of bioactive compounds was the bordeaux flowers dried at drying air temperature of 60 °C.

Impact of different kernel grades on volatile compounds profile, fatty acids and oxidative quality of cashew nut oil

In this study, the impact of kernel grade on the physicochemical quality, fatty acids, and volatile compounds of cashew nut oil was assessed. The oil samples were obtained from different classifications of nuts and analyzed for acid and peroxide values, color, fatty acids and volatile compounds. The broken kernel oils showed similar or superior quality to the whole kernel oil (LW3), especially samples B3 (batoque) and P3 (large piece), with acid, peroxide and color values equal to the one in LW3. The oils from less intact nuts showed high proportions of monounsaturated fatty acids (MUFA), with acid ratios higher than the ones in LW3 (64.47 to 65.28 %, while the latter displayed 63.33 %). Sample P3 showed higher proportions of volatile compounds not derived from oxidation. This study expands the possibility of valorizing lower commercial value cashew nuts by producing oil with adequate quality for consumption.