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1.
Molecules ; 26(12)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205651

RESUMO

High-pressure processing (HPP) has emerged over the last 2 decades as a good alternative to traditional thermal treatment for food safety and shelf-life extension, supplying foods with similar characteristics to those of fresh products. Currently, HPP has also been proposed as a useful tool to reduce food contaminants, such as pesticides and mycotoxins. The aim of the present study is to explore the effect of HPP technology at 600 MPa during 5 min at room temperature on alternariol (AOH) and aflatoxin B1 (AFB1) mycotoxins reduction in different juice models. The effect of HPP has also been compared with a thermal treatment performed at 90 °C during 21 s. For this, different juice models, orange juice/milk beverage, strawberry juice/milk beverage and grape juice, were prepared and spiked individually with AOH and AFB1 at a concentration of 100 µg/L. After HPP and thermal treatments, mycotoxins were extracted from treated samples and controls by dispersive liquid-liquid microextraction (DLLME) and determined by HPLC-MS/MS-IT. The results obtained revealed reduction percentages up to 24% for AFB1 and 37% for AOH. Comparing between different juice models, significant differences were observed for AFB1 residues in orange juice/milk versus strawberry juice/milk beverages after HPP treatment. Moreover, HPP resulted as more effective than thermal treatment, being an effective tool to incorporate to food industry in order to reach mycotoxins reductions.


Assuntos
Aflatoxinas/química , Bebidas/análise , Sucos de Frutas e Vegetais/análise , Frutas/química , Leite/química , Vitis/química , Animais , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Manipulação de Alimentos/métodos , Lactonas/química , Microextração em Fase Líquida/métodos , Micotoxinas/química , Espectrometria de Massas em Tandem/métodos
2.
Molecules ; 26(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208715

RESUMO

Vegetable processing pomace contains valuable substances such as natural colors that can be reused as functional ingredients. Due to a large amount of water, they are an unstable material. The aim of our research was to assess how the pretreatment method (thermal or nonthermal) affects the properties of powders obtained from beet juice and pomace after the freeze-drying process. The raw material was steamed or sonicated for 10 or 15 min, and then squeezed into juice and pomace. Both squeezed products were freeze-dried. The content of dry substance; L*, a*, and b* color parameters; and the content of betalain pigments were analyzed. Pretreatments increased the proportion of red and yellow in the juices. Steam and ultrasound caused a significant reduction in parameter b* in the dried pomace. A significant increase in betanin in lyophilizates was observed after pretreatment with ultrasound and steam for 15 min. As a result of all experiments, dried juices and pomaces can also be used as a colorant source. However, there is higher potential with pomaces due to their additional internal substances as well as better storage properties. After a few hours, juice was sticky and not ready to use.


Assuntos
Beta vulgaris/química , Betalaínas/isolamento & purificação , Extratos Vegetais/química , Antocianinas/análise , Antioxidantes , Beta vulgaris/metabolismo , Betacianinas/química , Betalaínas/química , Cor , Manipulação de Alimentos/métodos , Liofilização , Sucos de Frutas e Vegetais/análise , Fenóis/análise , Extratos Vegetais/metabolismo
3.
Molecules ; 26(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34066136

RESUMO

The valorization of food industry by-products as sources of bioactive compounds is at the forefront of research in functional foods and nutraceuticals. This study focuses on bioactives of apple cider by-products (ACBPs) with putative cardio-protective properties. Total lipids (TLs) were extracted from ACBPs of apple varieties that are low (ACBP1), medium (ACBP2), and high (ACBP3) in tannins and were further separated into polar lipids (PLs) and neutral lipids (NLs). The functionality of these lipid extracts and of their HPLC-derived lipid fractions/PL subclasses were assessed in vitro against human platelet aggregation induced by the thrombotic and inflammatory platelet agonists platelet-activating factor (PAF) and adenosine diphosphate (ADP). The fatty acid profile of PLs and their most bioactive lipid fractions were evaluated by GC-MS analysis. The PL extracts exhibited higher specificity against the PAF-induced platelet aggregation compared to their anti-ADP effects, while TL and NL showed lower bioactivities in all ACBPs. HPLC analysis unveiled that the most bioactive PL from all ACBPs were those in PL fraction 3 containing phosphatidylcholines (PCs). PLs from all ACBPs and their PC bioactives were rich in polyunsaturated fatty acids (PUFAs) and especially in the essential omega-6 (n-6) linoleic acid (LA) and omega-3 (n-3) alpha linolenic acid (ALA), with favorably low values of the n-6/n-3 PUFA ratio, thus providing a rationale for their higher anti-inflammatory bioactivities. Within this study, highly bioactive PL compounds with strong anti-inflammatory and anti-platelet properties were identified in ACBPs, which can be potentially utilized for producing cardio-protective functional foods and/or nutraceuticals.


Assuntos
Anti-Inflamatórios/farmacologia , Sucos de Frutas e Vegetais/análise , Frutas/química , Ácido Linoleico/farmacologia , Malus/química , Compostos Fitoquímicos/farmacologia , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Ácido alfa-Linoleico/farmacologia , Doadores de Sangue , Cromatografia Líquida de Alta Pressão , Alimento Funcional/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Fosfatidilcolinas/farmacologia
4.
Biosensors (Basel) ; 11(5)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068345

RESUMO

Carbendazim is a systemic benzimidazole-type fungicide with broad-spectrum activity against fungi that undermine food products safety and quality. Despite its effectiveness, carbendazim constitutes a major environmental pollutant, being hazardous to both humans and animals. Therefore, fast and reliable determination of carbendazim levels in water, soil, and food samples is of high importance for both food industry and public health. Herein, an optical biosensor based on white light reflectance spectroscopy (WLRS) for fast and sensitive determination of carbendazim in fruit juices is presented. The transducer is a Si/SiO2 chip functionalized with a benzimidazole conjugate, and determination is based on a competitive immunoassay format. Thus, for the assay, a mixture of an in-house developed rabbit polyclonal anti-carbendazim antibody with the standards or samples is pumped over the chip, followed by biotinylated secondary antibody and streptavidin. The WLRS platform allows for real-time monitoring of biomolecular interactions carried out onto the Si/SiO2 chip by transforming the shift in the reflected interference spectrum caused by the immunoreaction to effective biomolecular adlayer thickness. The sensor is able to detect 20 ng/mL of carbendazim in fruit juices with high accuracy and precision (intra- and inter-assay CVs ≤ 6.9% and ≤9.4%, respectively) in less than 30 min, applying a simple sample treatment that alleviates any "matrix-effect" on the assay results and a 60 min preincubation step for improving assay sensitivity. Excellent analytical characteristics and short analysis time along with its small size render the proposed WLRS immunosensor ideal for future on-the-spot determination of carbendazim in food and environmental samples.


Assuntos
Benzimidazóis/análise , Carbamatos/análise , Sucos de Frutas e Vegetais/análise , Fungicidas Industriais/análise , Imunoensaio , Luz , Análise Espectral
5.
Food Chem ; 362: 130168, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34090045

RESUMO

Multielement analysis and chemometric methods were proposed to discriminate the Sorrento lemon (PGI) juices according to geographical origin. In 2018 and 2019, 169 fruits from three farms in PGI area and two in not-PGI area were collected and analysed for essential and not-essential elements by ICP-MS. The PCA of multielement fingerprinting grouped lemon juices from PGI farms revealing a strong differentiation at small geographical scale. The S-LDA discriminated lemon juices for Mo, Ba, Rb, Mg, Co, Ca, Fe, Sr on the two production years, giving 97.7% correct classification, 98.5% accuracy and 93.8% external validation. The good correlation lemon juice vs cultivation soil and the soil discrimination by not-essential elements suggested the use of these elements as reliable indicators of lemon juice provenances. Despite lowering the number of variables, constituted by not-essential elements Ba, Rb, Ti, Co, the use of S-QDA discriminated the lemons juices with 87.5% accuracy and 83.9% validation.


Assuntos
Citrus/química , Análise de Alimentos/métodos , Metais/análise , Solo/química , Quimioinformática/métodos , Análise Discriminante , Análise de Alimentos/estatística & dados numéricos , Frutas/química , Sucos de Frutas e Vegetais/análise , Itália
6.
Artigo em Inglês | MEDLINE | ID: mdl-33957354

RESUMO

A novel in-syringe temperature-controlled liquid-liquid microextraction based on solidified floating ionic liquid (in-syringe TC-LLME-SFIL) combined with high performance liquid chromatography was developed for the simultaneous determination of monuron, chlorotoluron, atrazine, monolinuron, propazine and prometryn in commercial vegetable protein drinks. The samples were deproteinized by trichloroacetic acid and further cleaned up by solid phase extraction column. The ionic liquid tributyldodecylphosphonium tetrafluoroborate ([P4 4 4 12]BF4) was used as extraction solvent and dispersed into the depurated sample solution to form fine droplets with the assistance of heating and vortex. With the help of an ice bath, the ionic liquid phase solidified and floated on the surface of aqueous phase. After separation from the aqueous phase, the solidified ionic liquids were dissolved with acetonitrile and the resulting solution was analyzed by high performance liquid chromatography. Some extraction parameters, including type and amount of adsorbent, type and amount of ionic liquids, amount of NaCl, melting temperature and time of ionic liquid, vortex time, pH of sample solution, ice bath temperature and time, were investigated and optimized by single-factor experiment, Plackett-Burman design and Box-Behnken design. The results showed that good linearities (r ≥ 0.9994) were obtained in the concentration range of 7.8-1000.0 µg/L. The limits of detection and quantification were in the range of 0.25-2.59 µg/L and 0.82-8.63 µg/L, respectively. The spiked recoveries were 81.26-118.42% with the relative standard deviation (RSD, n = 3) lower than 8.17%. The present method was successfully applied to the simultaneous determination of triazine and phenylurea herbicides in vegetable protein drinks.


Assuntos
Sucos de Frutas e Vegetais/análise , Microextração em Fase Líquida , Resíduos de Praguicidas , Compostos de Fenilureia , Triazinas , Cromatografia Líquida de Alta Pressão/métodos , Herbicidas/análise , Herbicidas/isolamento & purificação , Líquidos Iônicos/química , Limite de Detecção , Modelos Lineares , Microextração em Fase Líquida/instrumentação , Microextração em Fase Líquida/métodos , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/isolamento & purificação , Compostos de Fenilureia/análise , Compostos de Fenilureia/isolamento & purificação , Proteínas de Vegetais Comestíveis/análise , Reprodutibilidade dos Testes , Seringas , Triazinas/análise , Triazinas/isolamento & purificação
7.
J Food Sci ; 86(6): 2445-2456, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33963549

RESUMO

The interactions between polysaccharides and phenolics in foods affect their physicochemical properties and bioactivity. Pectin and catechin/procyanidin present in plants ubiquitously and attracting more attentions for the potential health benefits. This work investigates the interactions between high methoxyl pectin and catechin/procyanidin in a simulative juice model using multiple microscopic and spectroscopic approaches and their influences on the antioxidant activity of phenolics were evaluated in the Caco-2 cells model. The results showed that pectin with either of phenolic compunds exhibited lower transmittance, zeta potential, viscosity, and larger particle size than it alone. The morphology of pectin complexes with either of phenolics under experimental conditions (pH = 3.5) was observed. The ΔH° (-6.821 kJ mol-1 ) and ΔS° (6.357×10-2  kJ mol-1 ) indicated that pectin interacts with procyanidin via electrostatic interaction, whereas hydrophobic interaction was the dominant drive force between pectin and catechin (ΔH° = 1.422 kJ mol-1 ; ΔS° = 13.048 × 10-2  kJ mol-1 ). The antioxidant activities of catechin/procyanidin decreased while binding with pectin based on indexes of glutathione peroxidase, total superoxide dismutase, total antioxidant capacity, and malondialdehyde. PRACTICAL APPLICATION: The findings of this work indicated that the physicochemical property of pectin and the antioxidant activity of catechin/procyanidin were influenced by the interactions between pectin and catechin/procyanidin in a simulative food system. This study provides insights into the molecular interactions between pectin and phenolics in a simulative food system.


Assuntos
Antioxidantes/farmacologia , Biflavonoides/farmacologia , Catequina/farmacologia , Interações Medicamentosas , Sucos de Frutas e Vegetais/análise , Pectinas/farmacologia , Proantocianidinas/farmacologia , Antioxidantes/química , Biflavonoides/química , Células CACO-2 , Catequina/química , Humanos , Pectinas/química , Proantocianidinas/química , Espectrometria de Fluorescência
8.
Food Chem ; 359: 129804, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34015560

RESUMO

Mutual adulterations of lemon and lime juices may be detected using coumarins and psoralens as markers. Poor manufacturing practices or legal but mechanically intense processing of lemons were recently suspected to lead to false accusations of deliberate adulterations with lime juices due to potentially unspecific markers. Therefore, we studied coumarin and psoralen profiles in carefully dissected flavedo, albedo, and endocarp of lime and lemon as well as in juices produced under variable mechanical stresses at laboratory and pilot plant scale. Although the marker herniarin was detectable in juices from lime and harshly extracted lemons at low levels, isopimpinellin, bergapten and the herein proposed, tentatively assigned 5-geranyloxy-8-methoxypsoralen represented unambiguously lime-specific markers. Coumarin and psoralen data also allowed differentiating juices produced at differing degrees of mechanical stress. The latter was also possible using quantitative 1H-NMR spectroscopy, which yielded best results when combined with HPLC data on coumarins and psoralens. In the future, the reported approach may be used for establishing a robust database prior to being used in industrial practice.


Assuntos
Citrus/química , Cumarínicos/análise , Análise de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Furocumarinas/análise , Espectroscopia de Ressonância Magnética
9.
Food Chem ; 359: 129920, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33951605

RESUMO

A method was validated for determining tebuconazole residues in coconut water, kernel and leaves using Liquid chromatography-Mass spectrometry/Mass spectrometry (LC-MS/MS) with electro spray ionization in positive ion mode. Samples were extracted with acetonitrile and subsequent clean-up was done using dispersive solid phase extraction. Recovery ranged between 70 and 114.39 % and the RSD was between 0.64 and 10.24 %. Root feeding studies with tebuconazole @ 5 and 10 mL/100 mL of water/tree revealed the presence of tebuconazole residues in coconut leaves until three days after treatment but dissipated to below quantifiable limit on 5th day at single dose while the residues went below quantifiable limit after 10 days at double the dose. Residues were below quantifiable limit in coconut water and kernel until three days. Data obtained from the study were used for estimating the risks associated with the exposures to tebuconazole residues in coconut.


Assuntos
Cocos/química , Sucos de Frutas e Vegetais , Resíduos de Praguicidas/química , Triazóis/química , Cromatografia Líquida de Alta Pressão , Sucos de Frutas e Vegetais/análise , Resíduos de Praguicidas/análise , Folhas de Planta/química , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Triazóis/análise
10.
Food Chem ; 359: 129889, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33934030

RESUMO

The objective was to analyze the phenolic composition, antioxidant capacity, and physical characteristics of 10 blackcurrant cultivars, their juices, and the enzymatic inhibition of dipeptidyl peptidase-IV, α-amylase, α-glucosidase, nitric oxide synthase, and cyclooxygenase-2. Fruit masses ranged from 0.47 to 1.22 g and diameters from 7.42 to 14.42 mm. For the juices, pH ranged from 2.80 to 2.96, soluble solids from 11.33% to 17.5%, total acidity from 3.17 to 4.26 g/100 mL, and viscosity from 1.28 to 273.83 mPa·s. Total anthocyanins (TA) ranged from 1.81 to 5.48 mg eq cyanidin 3-O-glucoside/100 g, total polyphenols (TP) from 7.67 to 39.70 mg eq gallic acid/100 g, total condensed tannins from 3.24 to 7.76 g eq catechin/100 g, and antioxidant capacity from 219.24 to 499.26 µmol eq Trolox/100 g. Juices of the cultivars Coronet and Consort contained the highest levels of TA, TP, and antioxidants. Whistler cultivar contained high concentrations of major anthocyanins. Juices from all cultivars favorably inhibited the activities of enzymes used as surrogate biochemical markers for T2 diabetes and inflammation.


Assuntos
Antocianinas/análise , Antioxidantes/análise , Extratos Vegetais/farmacologia , Polifenóis/análise , Proantocianidinas/análise , Ribes/química , Antocianinas/farmacologia , Inibidores de Ciclo-Oxigenase 2/análise , Inibidores da Dipeptidil Peptidase IV/análise , Frutas/química , Sucos de Frutas e Vegetais/análise , Inibidores de Glicosídeo Hidrolases/análise , Óxido Nítrico Sintase/antagonistas & inibidores , Fenóis/análise , Extratos Vegetais/química , Polifenóis/farmacologia , Proantocianidinas/farmacologia , alfa-Amilases/antagonistas & inibidores
11.
J Chromatogr A ; 1648: 462220, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-33992997

RESUMO

In this study, a new solid phase extraction method based on the use of a low-cost funnel-shaped partially carbonized cellulose filter paper as a sorbent has been developed. The sorbent is easily prepared by heating the folded filter paper wetted with sulfuric acid solution and can be reused for several times. It is combined with dispersive liquid-liquid microextraction and used for the extraction of some pesticide residues from fruit juice samples prior to their analysis by gas chromatography-flame ionization detection. In this work, limits of detection and quantification were in the ranges of 0.30-0.61 and 1.0-2.0 µg L-1, respectively, and relative standard deviations ranged between 3 and 6% for intra- (n=5) and inter-day (n=5) precisions at a concentration of 25 µg L-1 of each pesticide. The enrichment factors of 452-751 were achieved. Extraction recoveries were in the range of 45-75%. The calibration curves had wide linear ranges with a good linearity (coefficient of determination ≥ 0.994). Finally, efficiency of the method was apprised by determining the analytes in fruit juice samples and relative recoveries were found to be in the range of 85-101%.


Assuntos
Celulose/química , Sucos de Frutas e Vegetais/análise , Resíduos de Praguicidas/isolamento & purificação , Praguicidas/análise , Adsorção , Cromatografia Gasosa , Frutas/química , Química Verde , Microextração em Fase Líquida/métodos , Extração em Fase Sólida/métodos , Solventes/química
12.
Food Chem ; 359: 129855, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33940475

RESUMO

Enzymatic browning control of cloudy fruit juice with natural substances has received much attention for improving its nutritional and commercial value. This study explored the anti-browning potential of Rosa roxburghii in apple juice. The anti-browning effects and mechanisms were evaluated by serial measurements of appearance, browning index, polyphenol oxidase (PPO) activity, UPLC-QE-Orbitrap-MS identification, inhibition kinetics and molecular docking. The results showed that Rosa roxburghii juice (0.25%-1.25% w/w) could effectively inhibit browning and PPO activity of apple juice. Ascorbic acid (1.67 g/100 g) as a reducing agent was a main anti-browning factor. Furthermore, seven phenolic compounds in Rosa roxburghii were screened as PPO inhibitors. Representative phenolic inhibitors induced mixed or competitive inhibition of PPO, mainly driven by hydrophobic forces and hydrogen bonds. This work demonstrates that Rosa roxburghii is a promising natural anti-browning ingredient to control the browning of cloudy apple juice due to abundant ascorbic acid and PPO inhibitors.


Assuntos
Catecol Oxidase/antagonistas & inibidores , Sucos de Frutas e Vegetais/análise , Malus/química , Rosa/metabolismo , Catecol Oxidase/metabolismo , Simulação de Acoplamento Molecular
13.
J Food Sci ; 86(6): 2374-2386, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33908625

RESUMO

The synergistic effects of ultrasound and ß-d-glucosidase in aroma of orange juice were investigated. ß-d-Glucosidase significantly increased the content of ester, aldehyde, alcohol, terpene, acid, and phenol, and insignificantly increased the ketone content in orange juice. Enzyme-treated orange juice, compared with fresh untreated orange juice, was found to contain 15 novel aroma compounds, whereas three aroma compounds disappeared. Ultrasound improved the enzymatic action and the retention of more active flavors in juice than treatment with enzyme alone. However, simultaneous ultrasound and enzyme treatment decreased aroma quality. Therefore, the choice of the mode of ultrasound treatment is highly important. The present investigation will provide a reference for aroma-enhancing application of ultrasound combined with ß-D-glucosidase. PRACTICAL APPLICATION: The study supplies a reference method for the aromatization of fruit juice.


Assuntos
Citrus sinensis/química , Sucos de Frutas e Vegetais/análise , Glucosidases/metabolismo , Odorantes/análise , Ondas Ultrassônicas , Citrus sinensis/metabolismo , Citrus sinensis/efeitos da radiação
14.
J Food Sci ; 86(5): 1946-1962, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33844286

RESUMO

Specific heat capacity ( C P ) is regarded as a fundamental parameter for the design, operation, and optimization of the heat transfer equipment widely used in the food industry. Using the calorimetric ASTM E1269-11 standard procedure, the C P -temperature ( C P ( T ) ) curves of fruit juice model systems prepared at different mass fractions of fructose/glucose/sucrose/citric acid/pectin and water were measured. Thus, experimental data of C P for solid samples in crystalline and amorphous states from -80 °C up to the melting temperature range and for aqueous samples from -80 to 110 °C were generated. In the tested temperature interval, the C P of crystalline, amorphous, and aqueous samples were found to be in the ranges of 0.037 ± 0.020 to 5.61 ± 0.04; 0.061 ± 0.004 to 3.12 ± 0.19, and 0.363 ± 0.05 to 3.24 ± 0.14 kJ/kg °C, respectively. Also, a generalized empirical equation based on the type and concentration of components was developed to predict the C P ( T ) curves of the studied samples. The proposed equation exhibited a low error sum of squares (SSE <  57.3) and a high coefficient of determination (R2 > 0.927). An analysis of variance (ANOVA) was performed with a confidence level of 95% (p < 0.05). The C P ( T ) curves were influenced by temperature, thermal transitions, water, solid types, and compound interactions. Glucose was one of the solids that most significantly influenced the C P values of samples. PRACTICAL APPLICATION: The experimental specific heat capacity data and empirical equation proposed in this study are relevant to the design, evaluation, and optimization of heat transfer equipment involved in many foods and biochemical industrial processes such as cryopreservation, frozen storage, freezing, chilling, drying, and the cooking of hard candies.


Assuntos
Varredura Diferencial de Calorimetria/métodos , Frutose/química , Sucos de Frutas e Vegetais/análise , Glucose/química , Temperatura Alta , Sacarose/química , Água/química , Temperatura
15.
Int J Food Microbiol ; 347: 109169, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-33813131

RESUMO

The isolation of autochthonous yeast species presents a good strategy to select new microorganisms for developing an adequate inoculum to carry out fermentations and generate representative products of the cider production zone. However, non-Saccharomyces yeasts have been considered to have low capacity to carry out a complete fermentation as Saccharomyces cerevisiae. In this work, five autochthonous yeasts from a cider fermentation process were isolated and identified as Saccharomyces cerevisiae, Kluyveromyces marxianus, Pichia membranaefaciens, P. kluyveri and Zygosaccharomyces rouxii. A series of fermentations were developed at laboratory level, using each species individually and it was observed that only S. cerevisiae was able to finish the process. K. marxianus consumed less than 50% of the sugars; P. kluyveri and Z. rouxii consumed less than 70% and P. membranaefaciens consumed more than 90% but the yield (ethanol produced for sugar consumed (YP/S)) was 0.39. Nevertheless, the addition of magnesium, zinc and nitrogen increased the fermentative capacity of almost all species: K. marxianus, Z. rouxii and P. kluyveri, showed an increase in ethanol production when nutrients were added, obtaining more than 80 g/L of ethanol, and showing that those nutrients are necessary to complete the fermentation. This work describes the potential use of different non-Saccharomyces species to carry out fermentation of apple juice and highlights the importance of certain nutrients to enable an efficient alcoholic fermentation and the generation of desirable volatile compounds for cider production.


Assuntos
Bebidas Alcoólicas/microbiologia , Nutrientes/metabolismo , Leveduras/metabolismo , Bebidas Alcoólicas/análise , Etanol/análise , Etanol/metabolismo , Fermentação , Sucos de Frutas e Vegetais/análise , Sucos de Frutas e Vegetais/microbiologia , Malus/microbiologia , Nutrientes/análise , Especificidade da Espécie , Leveduras/classificação , Leveduras/isolamento & purificação
16.
Int J Food Microbiol ; 347: 109189, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-33838479

RESUMO

Salmonella enterica serovar Typhimurium can survive some extreme environment in food processing, and vanillin generally recognized as safe is bactericidal to pathogens. Thus, we need to explore the responses of S. Typhimurium to vanillin in order to apply this antimicrobial agent in food processing. In this study, we exposed S. Typhimurium to commercial apple juice with/without vanillin (3.2 mg/mL) at 45 °C for 75 min to determine the survival rate. Subsequently, the 10-min cultures were selected for transcriptomic analysis. Using high-throughput RNA sequencing, genes related to vanillin resistance and their expression changes of S. Typhimurium were identified. The survival curve showed that S. Typhimurium treated with vanillin were inactivated by 5.5 log after 75 min, while the control group only decreased by 2.3 log. Such a discrepancy showed the significant antibacterial effect of vanillin on S. Typhimurium. As a result, 265 differentially expressed genes (DEGs) were found when coping with vanillin, among which, 225 showed up-regulation and 40 DEGs were down-regulated. Treated with vanillin, S. Typhimurium significantly up-regulated genes involved in cell membrane, acid tolerance response (ATR) and oxidative stress response, cold shock cross-protection, DNA repair, virulence factors and some key regulators. Firstly, membrane-related genes, including outer membrane (bamE, mepS, ygdI, lolB), inner membrane (yaiY, yicS) and other proteins (yciC, yjcH), were significantly up-regulated because of the damaged cell membrane. Then, up-regulated proteins associated with arginine synthesis (ArgABCDIG) and inward transportation (ArtI, ArtJ, ArtP and HisP), participated in ATR to pump out the protons inside the cell in this scenario. Next, superoxide stress response triggered by vanillin was found to have a significant up-regulation as well, which was controlled by SoxRS regulon. Besides, NADH-associated (nuoA, nuoB, nuoK, nadE, fre and STM3021), thioredoxin (trxA, trxC, tpx and bcp) and glutaredoxin (grxC and grxD) DEGs led to the increase of the oxidative stress response. Cold shock proteins such as CspA and CspC showed an up-regulation, suggesting it might play a role in cross-protecting S. Typhimurium from vanillin stress. Furthermore, DEGs in DNA repair and virulence factors, including flagellar assembly, adhesins and type III secretion system were up-regulated. Some regulators like fur, rpoE and csrA played a pivotal role in response to the stress caused by vanillin. Therefore, this study sounds an alarm for the risks caused by stress tolerance of S. Typhimurium in food industry.


Assuntos
Benzaldeídos/farmacologia , Conservantes de Alimentos/farmacologia , Sucos de Frutas e Vegetais/microbiologia , Malus/microbiologia , Salmonella typhimurium/efeitos dos fármacos , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Proteínas de Bactérias/genética , Benzaldeídos/análise , Conservantes de Alimentos/análise , Sucos de Frutas e Vegetais/análise , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Salmonella typhimurium/genética , Transcriptoma/efeitos dos fármacos
17.
Food Chem ; 355: 129616, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33799262

RESUMO

Attenuated Total Reflectance-Fourier Transform Infrared spectroscopy (ATR-FTIR), in combination with chemometrics, was explored as a rapid method of detecting sugar adulteration in coconut water. In a simulated experiment, coconut water was substituted with binary sugars, mixed sugars, and high fructose corn syrup and discriminated using the fingerprint infrared band region between 1200 and 950 cm-1. Principal component analysis (PCA) performed on data pre-processed by the Savitzky-Golay smoothing and gap-segment derivative, revealed data clusters discernible by the type and level of substituted sugars, enabling visual diagnosis of the similarity and anomalous features in the dataset. Statistical performance metrics following a cross-validated partial least square (PLS) regression indicated the prediction of adulterant sugars at single-digit percent substitutions. A parallel exploratory analysis of 31 different commercial coconut water samples showed a distinct PCA clustering for samples bearing the label "added sugar", suggesting the potential use of the methods to screening samples for undeclared sugar additions.


Assuntos
Cocos/química , Sucos de Frutas e Vegetais/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise por Conglomerados , Cocos/metabolismo , Análise dos Mínimos Quadrados , Análise de Componente Principal , Açúcares/análise
18.
Chem Pharm Bull (Tokyo) ; 69(3): 286-290, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33642478

RESUMO

Monitoring analysis of 14 per- and polyfluoroalkyl substances (PFAS), 9-chlorohexadecafluoro-3-oxanonane-1-sulfonate (F-53B) and dodecafluoro-3H-4,8-dioxanonanoate (ADONA) in bottled drinking water, tea and juice samples was performed using LC coupled with tandem mass spectrometry (LC-MS/MS) and solid-phase extraction (SPE). In the electrospray negative ion mode, the limit of detection and limit of quantification (LOQ) values were 0.1 to 0.8 ng/mL and 0.2 to 1.6 ng/mL, respectively. The calibration curves were linear from LOQ to 50 ng/mL (r2 > 0.999). The SPE procedure (Presep PFC-II) was utilized for sample preparation and recovery rates for three standards (35, 70 and 140 ng/L) were 80.4-118.8% with relative standard deviation (RSD) ≤ 0.6%. Using the developed method, various samples (n = 54) from Japanese markets were investigated for PFAS and F-53B contamination, and values below the LOQ were observed. It is concluded that for monitoring products in the Japanese market, our method represents a significant improvement over complex techniques for the quantification of PFAS and related compounds from various foods.


Assuntos
Alcanossulfonatos/análise , Água Potável/análise , Fluorcarbonetos/análise , Sucos de Frutas e Vegetais/análise , Chá/química , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise
19.
Food Chem ; 352: 129367, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33684718

RESUMO

About 90% of grapefruit in Florida are affected by Huanglongbing (HLB). HLB negatively affects the organoleptic properties of grapefruit juice because affected trees overproduce bitter secondary-metabolites, mostly naringin. The objective of this research was to remove naringin from HLB-affected grapefruit juice using microporous-adsorbents and to investigate how debittering affected narirutin, limonoids, bergamottin, and consumer acceptability. The adsorption kinetics of naringin on seven adsorbent resins obeyed pseudo-second order. PAD550 and PAD600 showed better static adsorption/desorption. Adsorption-isotherms on these resins were better fitted on Temkin-Pyzhev-model. On a fixed-bed-column packed with PAD550 resin, a slower loading rate increased its breakthrough volume before naringin in effluent reached its taste-threshold. In addition to naringin being reduced to below its taste-threshold, debittering significantly decreased the content of limonin, nomilin, and bergamottin. A consumer taste panel rated debittered and half-debittered juices higher for overall acceptability than the untreated. The half-debittered juice was ranked the most preferred while untreated was the least preferred.


Assuntos
Citrus paradisi/química , Citrus paradisi/microbiologia , Sucos de Frutas e Vegetais/análise , Furocumarinas/análise , Doenças das Plantas/microbiologia , Resinas Sintéticas/química , Paladar , Porosidade
20.
Food Chem ; 352: 129430, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33691211

RESUMO

The present work reports the development of a novel electrochemical sensor for the selective detection of fructose. The sensor was developed through electropolymerization of a molecularly imprinted polymer film on a reduced graphene oxide modified electrode. The modified electrode was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscopy, atomic force microscopy and RAMAN spectroscopy. Through the application of the modified electrode, the recognition of fructose molecules occurred in a concentration range of 1.0 × 10-14 to 1.0 × 10-11 mol L-1, under a Langmuir adsorption isothermal model. The sensitivity and limits of detection and quantification obtained for the sensor were 9.9 × 107 A L mol-1, 3.2 × 10-15 mol L-1 and 1.1 × 10-14 mol L-1, respectively. The analytical method used for the detection of fructose presented good reproducibility, stability and accuracy, and was successfully applied for the quantification of this sugar in orange, apple and grape juices.


Assuntos
Eletroquímica/instrumentação , Análise de Alimentos/instrumentação , Frutose/análise , Sucos de Frutas e Vegetais/análise , Grafite/química , Polímeros Molecularmente Impressos/química , Eletrodos , Frutose/química , Limite de Detecção , Polímeros Molecularmente Impressos/síntese química , Reprodutibilidade dos Testes
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