•Study of the effects of thermal treatment on the formation of 5-HMF and sugars.•Thermal treatment was optimised using full factorial design 22 with central point.•Intralaboratory analytical method ...validation was performed according Eurachem.•Results suggest a possible resistance to 5-HMF formation in stingless bee honey.
This study aimed to assess 5-hydroximethylfurfural and carbohydrates (fructose, glucose, and sucrose) in 13 stingless bee honey samples before and after thermal treatment using a capillary electrophoresis method. The methods were validated for the parameters of linearity, matrix effects, precision, and accuracy. A factorial design was implemented to determine optimal thermal treatment conditions and then verify the postprocedural 5-HMF formation, but once 5-HMF were <LOQ was not possible to build a response surface. The methods applied to samples obtained from Brazil, expressed good linearity, precision, and accuracy. None of the thirteen in natura samples presented 5-HMF, and carbohydrate levels ranged from 48.59% to 69.36%. In the same conditions of thermal treatment, Apis mellifera honey presented higher 5-HMF content than stingless bee honey. Results suggest that a high temperature related to briefer thermal treatment could be an efficient way to extend shelf life without affecting 5-HMF content in stingless bee honey.
This paper proposes an innovative sub-minute capillary zone electrophoresis method and a simple sample preparation procedure for simultaneous nitrate and nitrite determination. The novelty of the ...method is the simplicity of execution and the capacity to separate the analytes in less than 0.5min. The BGE is composed of 10mmolL−1 perchloric acid and 40mmolL−1 β-alanine at pH 3.96. Thiocyanate was used as an internal standard. The method was validated following the Eurachem guidelines and applied to the analysis of 14 baby food samples. Of these samples, one had nitrate levels above that permitted by Brazilian legislation (250mgkg−1) and for all samples the nitrite concentrations were under the limit of quantification. The good analytical performance verified for this method indicates that it is suitable for implementation in food laboratories for the routine determination of nitrate and nitrite as an alternative to the official method provided by the AOAC.
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•A sub-minute CZE method was developed for the determination of nitrate and nitrite.•The CZE method was applied in the analysis of baby foods.•Sample preparation step was simple and effective to extract the analytes.•Analytical validation was performed according to the Eurachem guidelines.•The CZE method showed good analytical performance to the analysis of baby foods.
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•Honey produced by four different species of stingless bees were analyzed.•Organic acids were quantified for the first time in Brazilian stingless bee honey.•Thirteen aliphatic ...organic acids were quantified by capillary electrophoresisGluconic, lactic, and acetic acids were predominant in all samples.
This study aimed to investigate for the first time fourteen aliphatic organic acids (AOA) in honeys produced by different species of Brazilian stingless bees (Melipona bicolor, Scaptotrigona bipunctata, Melipona quadrifasciata, and Melipona marginata) and characterize them regarding their physicochemical properties. Thirteen AOAwere quantified in the samples, in which five of them (malonic, fumaric, glycolic, glutaric, and propionic acids) were identified for the first time instingless bee honey (SBH). Acetic, gluconic, and lactic acids were predominant in all the samples analyzed varying from 0.0067 ± 0.0001 to 1.5993 ± 0.0003 g 100 g−1, 0.0808 ± 0.0007 to 1.3460 ± 0.0006 g 100 g−1, and 0.0370 ± 0.000 to 0.5760 ± 0.0006 g 100 g−1, respectively. Most physicochemical properties showed significant differences (p < 0.05) among the samples. However, it was observed that the water activity (Aw) did not differ significantly between honey samples produced by the same species. Moreover, it is important to highlight the high moisture content, Aw, and free acidity that were found in the range of 29.6 to 40.1 g 100 g−1, 0.75 to 0.84, and 37.8 to 123 mEq kg−1, respectively. This information reinforces such peculiar characteristics of SBH and a need to deeply investigate the physical and chemical characteristics of honey from different species of stingless bees. In conclusion, it was observed that the honey samples of the different stingless bee species presented a great variation regarding their AOA content, highlighting acetic, gluconic, and lactic acids as the major AOA in all the samples. However, since this was an exploratory study, it was not possible to find any correlation between honey produced by the same species.
In this study, twenty free amino acids (FAA) were investigated in samples of bracatinga (Mimosa scabrella) honeydew honey (BHH) from Santa Catarina (n = 15) and Paraná (n = 13) states (Brazil), ...followed by chemometric analysis for geographic discrimination. The FAA determination was performed by gas chromatography-mass spectrometry (GC-MS) after using a commercial EZ:faast™ kits for GC. Eight FAA were determined, being proline, asparagine, aspartic and glutamic acids found in all BHH, with significant differences (p < 0.05). In addition, with the exception of proline, the others FAA (asparagine, aspartic and glutamic) normally showed higher concentrations in samples from Santa Catarina state, being that in these samples it was also observed higher FAA sums (963.41 to 2034.73 mg kg
) when compared to samples from Paraná state. The variability in the results did not show a clear profile of similarity when the heatmap and hierarchical grouping were correlated with the geographic origin and the concentration of eight determined FAA. However, principal component analysis (PCA) demonstrated that serine, asparagine, glutamic acid, and tryptophan were responsible for the geographic discrimination among samples from Santa Catarina and Paraná states, since they were the dominant variables (r > 0.72) in the PCA. Therefore, these results could be useful for the characterization and authentication of BHH based on their FAA composition and geographic origin.
► A fast CE method was developed for determination of three sugars in honey samples. ► Peakmaster® software was used to optimize the BGE composition. ► Under optimized CE conditions, separation of ...the sugars was achieved in less than 2min. ► The method was validated and successfully applied to seven multifloral honey samples. ► Samples were dissolved in H2O, filtered and injected with other no pretreatment required.
In this study, the determination of fructose, glucose and sucrose by capillary electrophoresis (CE) was investigated. The tendency of the analyte to undergo electromigration dispersion and the buffer capacity were evaluated using the Peakmaster® software and considered in the optimization of the background electrolyte, which was composed of 20mmolL−1 sorbic acid, 0.2mmolL−1 CTAB and 40mmolL−1 NaOH at pH 12.2. Under optimal CE conditions, the separation of the substances investigated was achieved in less than 2min. The detection limits for the three analytes were in the range of 0.022 and 0.029gL−1 and precision measurements within 0.62–4.69% were achieved. The proposed methodology was applied in the quantitative analysis by direct injection of in honey samples to determine the main sugars presents. The samples were previously dissolved in deionized water and filtered with no other sample treatment. The mean values for fructose, glucose and sucrose were in the ranges of 33.65–45.46g 100g−1, 24.63–35.06g 100g−1 and <0.22–1.32g 100g−1, respectively. The good analytical performance of the method makes it suitable for implementation in food laboratories for the routine analysis of honey samples.
Honeydew honey has differentiated chemical and physicochemical characteristics besides potential functional properties such as antimicrobial, anti-inflammatory and antioxidant. In this sense, the ...interest and consumption of this honey as a functional product by the food industry and consumers have increased. Honeydew honeys usually present dark color, a lower content of monosaccharides and higher values of pH, acidity, electric conductivity, proteins, minerals, phenolic compounds, and oligosaccharides compared to blossom honeys, which contribute to its outstanding biological activities. Consequently, contaminations and adulterations of this honey can occur and compromise the quality, safety and authenticity of honeydew honey. Thus, detailed knowledge of the composition and properties of honeydew honeys is of great importance, especially considering that honeydew honeys are still few studied and therefore underestimated. Therefore, in this review, the physicochemical characteristics, chemical and bioactive composition, functional and health-promoting properties of honeydew honey as well as contamination, adulteration and authenticity of this honey are summarized.
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•Honeydew honey (HH) has antioxidant, antimicrobial, and anti-inflammatory potential.•Benzoic, protocatechuic, p-coumaric, salicylic acids, and rutin were abundant in HH.•Proline, phenylalanine, and glutamic acid were reported as the major amino acid.•High content of melezitose, raffinose, and citric acid are commonly found in HH.•Physicochemical parameters and individual compounds have been studied for authenticity.
•Physicochemical profile of thirty-three samples of stingless bee honey are reported.•Moisture, acidity and carbohydrate of stingless bee honeys differ of Apis mellifera.•Honey of stingless bees have ...remarkable antioxidant activity and total phenolic.•First reports of K, Na, Ca, Mg and Mn in honey of stingless bees.
This study investigates the physicochemical properties, majority minerals, total phenolic compounds and antioxidant activity of stingless bee honey. Thirty-three samples from ten species were analyzed. The results show moisture as 23.1–43.5% (w/w), the electrical conductivity as 0.150–1.34mScm−1, the free acid as 16.2–139mEqkg−1, the pH as 3.33–6.56, the diastase activity as 4.34–49.6 in Göthe units, the insoluble solids as 55.2–76.1°Brix, the carbohydrates as 48.6–70.5% (w/w) sucrose and the 5-hydroxymethylfurfural (5-HMF) was below the limit of quantitation (LOQ). The most abundant element in the samples was potassium followed by calcium sodium, magnesium and manganese. Stingless bee honeys possess relevant amounts of phenolic compounds and antioxidant activity, suggesting a source of natural antioxidants. The results show that there is great variability in the composition of honey from stingless bees of different species, predominantly flowering and geographical origin. However, it was not possible to identify the real factor influencing its features.
The aim of this study was to investigate the free individual phenolics and the
in vitro
antioxidant capacity of blackberry, acerola, yellow guava, guabiju, jambolan and jabuticaba fruits in two ...edible stages. Of the thirty-three phenolics investigated by liquid chromatography - tandem mass spectrometry (LC-MS/MS), twenty-five were quantified and the major ones were catechin, isoquercitrin, epicatechin and gallic acid. The highest values for the total phenolic content (in dry matter) were observed for acerola (83.6 to 97.7 mg gallic acid equivalents g
−1
DM) and blackberry (18.9 to 28.3 mg gallic acid equivalents g
−1
DM); however, acerola, jabuticaba, and blackberry showed the highest antioxidant capacities (134.6 to 1120.4 mg Trolox equivalents g
−1
for 2,2-diphenyl-1-picrylhydrazyl and 43.6 to 501.8 μmol Trolox equivalents g
−1
for ferric reducing antioxidant power). For most fruits, the antioxidant capacity decreased during the ripening, possibly due to a decrease in the concentration of most of the phenolics.
Although parabens have several features of ideal preservatives, different studies have shown that they may affect human health due to their estrogenic activity. Therefore, various strategies have ...been applied to reduce their skin penetration. However, the effect of paraben combinations on transdermal permeation has not yet been investigated. Thus, the objective of this study was to evaluate paraben permeation in pig ear skin using a Franz diffusion cell system with capillary electrophoresis detection, in order to identify which paraben combinations (defined by a factorial design) have the lowest skin permeation. The permeation of isolated parabens was also evaluated and the permeation characteristics, obtained by the Moser model, confirmed that lipophilicity and molecular weight may influence the systemic absorption of these compounds. In previous tests using isolated parabens, methyl and ethyl parabens presented greater retention in the epidermis compared to the dermis, while propyl and butyl parabens had similar retention profiles in these layers. An increase in ethanol concentration and experimental time promoted greater parabens retention in the dermis compared to the epidermis. The binary combinations of methyl and ethyl parabens as well as of methyl and propyl parabens (added to several cosmetic products in order to increase the antimicrobial spectrum) reduced significantly their permeation rates through pig ear skin (with the exception of EP), probably due to the high retention of these parabens in the epidermis and dermis.
Common bean (Phaseolus vulgaris L.) seeds are an economical protein source rich in bioactive compounds with antioxidant activity. In this work, we evaluated processed seeds from two common bean ...cultivars regarding protein profile and antioxidant capacity before and after enzymatic digestion in vitro. We provided protein maps by two‐dimensional electrophoresis (2‐DE) of seeds germinated during 36 h and 72 h. The principal component analysis (PCA) showed that protein abundance had more variation on germination times than the cultivar ones. Seeds germinated for 36 h showed greater antioxidant capacity compared to germination for 72 h and cooking, before and after enzymatic digestion. In protein isolates, cooking associated with digestion provided better antioxidant capacity. Germination time influences protein expression as well as the antioxidant capacity of common beans. Furthermore, in vitro digestion increases the antioxidant capacity of cooked bean protein isolates.
Protein profile and antioxidant capacity of processed seeds from two common bean cultivars.
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