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1.
Food Chem ; 352: 129321, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33667922

RESUMEN

Low turbidity and low discolouration is targeted in clear red grape juice (RGJ) production. Depending on type of clarification agents, substantial discolouration may occur. Therefore, this study was undertaken to show effects of various clarification treatments (bentonite and chitosan, and combinations of "bentonite + gelatin (B + G)," "bentonite + casein (B + CA)," "bentonite + albumin (B + A)" and "bentonite + chitosan (B + CTS)" on turbidity, color (ACNs, color density-CD and polymeric color-PC), phenolics and antioxidant activity (AOA) during RGJ clarification. Casein alone (4.0 NTU and 9.1% ACN loss) and in combination with bentonite (4.4 NTU and 12.3% ACN loss), followed by B + A (5.7 NTU and 12.3% ACN loss) resulted in best clarity and was associated with least change in ACNs. These clarifications also resulted in high CD (intensive red color) and low PC (low browning). At all dosages, gelatin and albumin were associated with highest ACN losses, while casein in greatest retention. "Bentonite + casein," followed by "bentonite + albumin," achieved the best clarification of RGJ.


Asunto(s)
Antocianinas/análisis , Antioxidantes/análisis , Jugos de Frutas y Vegetales/análisis , Fenoles/análisis , Vitis/química , Color
2.
Food Chem ; 352: 129327, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33690077

RESUMEN

This paper describes a voltammetric method and data analysis program developed for the detection of arsenic(III) in commercial apple juice. Arsenic(III) was detected using square wave stripping voltammetry with gold nanoparticle modified screen printed electrodes. The only sample pretreatment performed was the addition of a 100 mM phosphate buffer with a pH of 7. To compensate for interference from high ascorbic acid concentrations, a data analysis program was developed in MATLAB to fit a non-linear baseline, allowing for accurate peak height measurement. With this data analysis program, the developed methodology had a sensitivity of 0.1007 µA (µg L-1)-1 and a limit of detection of 16.73 µg L-1. A comparison between the voltammetric method and graphite furnace atomic absorption spectroscopy showed no bias in the voltammetric results and a good correlation between the two sets of predicted concentrations, with an R2 of 0.939.


Asunto(s)
Arsénico/análisis , Carbono/química , Electroquímica/instrumentación , Jugos de Frutas y Vegetales/análisis , Oro/química , Malus/química , Nanopartículas del Metal/química , Electrodos , Análisis de los Alimentos/instrumentación , Impresión , Factores de Tiempo
3.
Carbohydr Polym ; 260: 117770, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712128

RESUMEN

Chitin-derived three-dimensional nanomaterials has tremendous potential in pesticide residue analysis as an attractive green substitute for toxic solvents. The work presented herein focuses on constructing the environmentally friendly nitrogen-containing chitin-derived carbon microspheres (N-CCMP) for the efficient adsorption of neonicotinoid pesticides (NPs) including acetamiprid, clothianidin, imidacloprid and thiamethoxam. The N-CCMP displayed hierarchical porous structure, uniform size distribution, and excellent specific surface area of 680.8 m2 g-1. The N-CCMP with N-heterocyclic ring structure and surface oxygen functional groups exhibited good affinity to NPs, which was beneficial for the rapid adsorption. Then, the N-CCMP were utilized as sorbent in extraction of NP residues. Under the optimum conditions, the relative recoveries in water and juice sample were in the range of 85 %-116 % and 74 %-108 %, with relative standard deviations (RSDs) of 0.1 %∼5.2 % and 0.7 %∼5.2 %, respectively. The extraction performance of N-CCMP were still over 80 % after 5 times of reuse.


Asunto(s)
Carbono/química , Quitina/química , Microesferas , Neonicotinoides/química , Nitrógeno/química , Residuos de Plaguicidas/química , Adsorción , Cromatografía Líquida de Alta Presión , Agua Dulce/análisis , Jugos de Frutas y Vegetales/análisis , Neonicotinoides/análisis , Residuos de Plaguicidas/análisis , Porosidad , Espectrometría de Masas en Tándem
4.
Molecules ; 26(4)2021 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-33669973

RESUMEN

Phenolic acids represent about one-third of the dietary phenols and are widespread in vegetable and fruits. Several plants belonging to both vegetables and medical herbs have been studied for their hydroxycinnamic acid content. Among them, Echinacea purpurea is preferentially used for caffeic acid-derivatives extraction. The wine industry is a source of by-products that are rich in phenolic compounds. This work demonstrates that unripe grape juice (verjuice) presents a simple high-pressure liquid chromatography (HPLC) profile for hydroxycinnamic acids (HCAs), with a great separation of the caffeic-derived acids and a low content of other phenolic compounds when compared to E. purpurea and other grape by-products. Here it is shown how this allows the recovery of pure hydroxycinnamic acids by a simple and fast method, fast protein liquid chromatography (FPLC). In addition, verjuice can be easily obtained by pressing grape berries and filtering, thus avoiding any extraction step as required for other vegetable sources. Overall, the proposed protocol could strongly reduce the engagement of solvent in industrial phenolic extraction.


Asunto(s)
Ácidos Cumáricos/química , Fenoles/aislamiento & purificación , Vitis/química , Cromatografía Líquida de Alta Presión , Jugos de Frutas y Vegetales/análisis , Estructura Molecular , Fenoles/química
5.
Molecules ; 26(4)2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-33672156

RESUMEN

Fruits contain a number of useful substances including antioxidants. Their bio-accessibility after passing through the digestive tract is of primary importance when considering their benefits. In this respect, we investigated the effect of in vitro digestion on the phytochemicals of eight fruit juices. Freshly prepared juices from pomegranate, orange and grapefruit were used as well as commercially available juices from cherry, black grapes and aloe vera, blackberry and chokeberry, and two types of chokeberry and raspberries. Spectrophotometric and HPLC methods were used in order to analyse the sugar content, the total phenolic (TPC) and flavonoid contents (TFC), anthocyanins, phenolic acids and antioxidant activity. Principle component analysis was used to explain the differentiation among the types of fruit juice. Sugar recovery variation was between 4-41%. The bio-accessibility of TPC ranged from 13.52-26.49% and of flavonoids between 24.25-67.00%. The pomegranate juice and the juice of black grapes and aloe vera kept 58.12 and 50.36% of their initial anthocyanins content, while for the other samples less than 1.10% was established. As a result, a maximum of 30% remaining antioxidant activity was measured for some of the samples, but for most this was less than 10%. In conclusion, fruit juices are a rich source of biologically active substances, but a more detailed analysis of food transformation during digestion is needed.


Asunto(s)
Jugos de Frutas y Vegetales/análisis , Tracto Gastrointestinal/metabolismo , Fitoquímicos/metabolismo , Animales , Porcinos
6.
Molecules ; 26(4)2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33672773

RESUMEN

A caloric surplus and a sedentary lifestyle are undoubtedly known to be the leading causes of obesity. Natural products represent valuable allies to face this problematic issue. This study was planned to assess the effect of a white grape (Vitis vinifera) juice extract (WGJe) in diet-induced obese zebrafish (Danio rerio). Fish were divided into four different diet groups: (i) normally fed (NF); (ii) overfed (OF); (iii) WGJe-supplemented NF (5 mL/L in fish water); (iv) WGJe-supplemented OF. Body mass index (BMI) was extrapolated each week. After the fourth week, euthanized zebrafish were processed for both microscopic evaluations and gene expression analyses. OF zebrafish showed higher BMI values with respect to NF counterparts, an effect that was hindered by WGJe treatment. Moreover, histological analyses showed that the area of the adipose tissue, as well as the number, size, and density of adipocytes was significantly higher in OF fish. On the other hand, WGJe was able to avoid these outcomes both at the subcutaneous and visceral levels, albeit to different extents. At the gene level, WGJe restored the altered levels of ghrelin and leptin of OF fish both in gut and brain. Overall, our results support the anti-obesity property of WGJe, suggesting its potential role in weight management.


Asunto(s)
Adipocitos/efectos de los fármacos , Grasas/antagonistas & inhibidores , Ghrelina/antagonistas & inhibidores , Leptina/antagonistas & inhibidores , Extractos Vegetales/farmacología , Vitis/química , Animales , Modelos Animales de Enfermedad , Grasas/metabolismo , Jugos de Frutas y Vegetales/análisis , Ghrelina/genética , Ghrelina/metabolismo , Leptina/genética , Leptina/metabolismo , Estructura Molecular , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , ARN Mensajero/antagonistas & inhibidores , ARN Mensajero/genética , ARN Mensajero/metabolismo , Pez Cebra
7.
Food Chem ; 352: 129367, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33684718

RESUMEN

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.


Asunto(s)
Citrus paradisi/química , Citrus paradisi/microbiología , Jugos de Frutas y Vegetales/análisis , Furocumarinas/análisis , Enfermedades de las Plantas/microbiología , Resinas Sintéticas/química , Gusto , Porosidad
8.
Food Chem ; 352: 129430, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33691211

RESUMEN

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.


Asunto(s)
Electroquímica/instrumentación , Análisis de los Alimentos/instrumentación , Fructosa/análisis , Jugos de Frutas y Vegetales/análisis , Grafito/química , /química , Electrodos , Fructosa/química , Límite de Detección , Reproducibilidad de los Resultados
9.
J Agric Food Chem ; 69(5): 1727-1738, 2021 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-33527826

RESUMEN

A prototype dual-detection headspace-gas chromatography-mass spectrometry-ion mobility spectrometry (HS-GC-MS-IMS) system was used for the analysis of the volatile profile of 47 Citrus juices including grapefruit, blood orange, and common sweet orange juices without requiring any sample pretreatment. Next to reduced measurement times, substance identification could be improved substantially in case of co-elution by considering the characteristic drift times and m/z ratios obtained by IMS and MS. To discriminate the volatile profiles of the different juice types, extensive data analysis was performed with both datasets, respectively. By principal component analysis (PCA), a distinct separation between grapefruit and orange juices was observed. While in the IMS data grapefruit juices not from fruit juice concentrate could be separated from grapefruit juices reconstituted from fruit juice concentrate, in the MS data, the blood orange juices could be differentiated from the orange juices. This observation leads to the assumption that the IMS and MS data contain different information about the composition of the volatile profile. Subsequently, linear discriminant analysis (LDA), support vector machines (SVM), and the k-nearest-neighbor (kNN) algorithm were applied to the PCA data as supervised classification methods. Best results were obtained by LDA after repeated cross-validation for both datasets, with an overall classification and prediction ability of 96.9 and 91.5% for the IMS data and 94.5 and 87.9% for the MS data, respectively, which confirms the results obtained by PCA. Additional data fusion could not generally improve the model prediction ability compared to the single data, but rather for certain juice classes. Consequently, depending on the juice class, the most suitable dataset should be considered for the prediction of the class membership. This volatilomic approach based on the dual detection by HS-GC-MS-IMS and machine learning tools represent a simple and promising alternative for future authenticity control of Citrus juices.


Asunto(s)
Citrus/química , Jugos de Frutas y Vegetales/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Compuestos Orgánicos Volátiles/química , Citrus/clasificación , Análisis Discriminante , Jugos de Frutas y Vegetales/clasificación , Aprendizaje Automático , Análisis de Componente Principal
10.
Food Chem ; 350: 129242, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-33626398

RESUMEN

Herein, an electrospun polyacrylonitrile/nickel-based metal-organic framework nanocomposite (PAN/Ni-MOF) coating on a stainless steel wire was synthesized and employed as a novel nanosorbent for headspace solid-phase microextraction (HS-SPME) of organophosphorus pesticides (OPPs), diazinon (DIZ), and chlorpyrifos (CPS) from the diverse aqueous media followed by corona discharge ion mobility spectrometry (CD-IMS). Under the optimum experimental conditions, the calibration plots were linear in the range of 1.0-250.0 ng mL-1 for DIZ and 0.5-300.0 ng mL-1 for CPS with r2 > 0.999. The detection limits (S/N = 3) were 0.3 and 0.2 ng mL-1 for DIZ and CPS, respectively. The intra-day relative standard deviations (RSDs%) (n = 5) at the concentration levels of 20.0, 40.0, and 100.0 ng mL-1 were ≤ 5.2%. To investigate the extraction efficiency, PAN/Ni-MOF was employed to analyze various juice samples, including orange, apple, and grape juices, and in three water samples where it led to good recoveries ranged between 87% and 98%.


Asunto(s)
Cloropirifos/aislamiento & purificación , Diazinón/aislamiento & purificación , Espectrometría de Movilidad Iónica/métodos , Estructuras Metalorgánicas/química , Nanofibras/química , Níquel/química , Plaguicidas/aislamiento & purificación , Microextracción en Fase Sólida/métodos , Jugos de Frutas y Vegetales/análisis , Límite de Detección , Acero Inoxidable/análisis , Acero Inoxidable/química
11.
Int J Food Microbiol ; 342: 109092, 2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33607541

RESUMEN

Tomato is widely consumed and marketed as juice, puree, or fresh product. Nevertheless, 30% of its harvest volume is lost because of the fungus Alternaria alternata. This research aimed to provide early detection methods for this fungal decay on tomato juice and fresh fruit. Biomass content, CO2, O2 and volatile compounds (VOCs) during A. alternata growth in tomato juice and fruit at two ripening stages (breaker and red colour) were evaluated. Additionally, CO2 and VOCs data set were analysed with a hierarchical cluster technique (HCA) to explore the differences between inoculated and non-inoculated samples. Biomass was determined by gravimetry, CO2 and O2 by gas chromatography (GC), and VOCs by GC-mass spectrometry. Biomass content was not drastically modified by tomato's ripening stage (3-6 mg of dry weight). CO2 in tomato juice was considerably higher in the inoculated samples with A. alternata (27-63%) than in the non-inoculated ones (2.8-6.6%), regardless of the ripeness stage; while in tomato fruit CO2 was higher at breaker stage and inoculated with A. alternata (33-41%) than the remaining treatments (9-23%). It was also observed that, except for limonene, trans-sabinene hydrate, and rhodovibrin, VOCs' release during the interaction between tomato juice and A. alternata was different from the fresh tomato and A. alternata interaction. Only the HCA based on CO2 data showed clear differences between the inoculated and non-inoculated tomato juice and fruit at both ripening stages.


Asunto(s)
Alternaria/aislamiento & purificación , Jugos de Frutas y Vegetales/microbiología , Frutas/microbiología , Lycopersicon esculentum/microbiología , Alternaria/metabolismo , Biomasa , Dióxido de Carbono/análisis , Dióxido de Carbono/metabolismo , Microbiología de Alimentos , Frutas/química , Jugos de Frutas y Vegetales/análisis , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/metabolismo
12.
Molecules ; 26(1)2021 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-33466479

RESUMEN

Orange pomace (OP) is a solid waste produced in bulk as a byproduct of the orange juice industry and accounts for approximately 50% of the quantity of the fruits processed into juice. In numerous literature references there is information about diverse uses of orange pomace for the production of high-added-value products including production of natural antioxidant and antimicrobial extracts rich in polyphenols and flavonoids which can substitute the hazardous chemical antioxidants/antimicrobials used in agro-food and cosmetics sectors. In this work and for the first time, according to our knowledge, the eco-friendly aqueous vacuum microwave assisted extraction of orange pomace was investigated and optimized at real industrial scale in order to produce aqueous antioxidant/antimicrobial extracts. A Response Surface Optimization methodology with a multipoint historical data experimental design was employed to obtain the optimal values of the process parameters in order to achieve the maximum rates of extraction of OP total polyphenols and/or total flavonoids for economically optimum production at industrial scale. The three factors used for the optimization were: (a) microwave power (b) water to raw pomace ratio and (c) extraction time. Moreover, the effectiveness and statistical soundness of the derived cubic polynomial predictive models were verified by ANOVA.


Asunto(s)
Citrus sinensis/química , Flavonoides/análisis , Microondas , Extractos Vegetales/análisis , Polifenoles/análisis , Residuos Sólidos/análisis , Vacio , Fraccionamiento Químico/métodos , Industria de Procesamiento de Alimentos , Jugos de Frutas y Vegetales/análisis , Extractos Vegetales/química
13.
Food Chem ; 347: 129058, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33486367

RESUMEN

In the present work, a comprehensive phenolic analysis of fresh sugarcane juice from three different harvest seasons was performed and the effect of ohmic heating and ultrasound treatments on the phenolic content and color of the juice was evaluated. Among the 32 phenolic compounds identified, a total of 17 were quantified, comprising, in decreasing order of abundance, flavones (38-49 mg/L), dilignols (22-29 mg/L), and phenolic acid derivatives (17-30 mg/L). The main phenolic groups affected by the crop season (year and season) were flavones and phenolic acid derivatives. Juice treated by ohmic heating and ultrasound showed a total phenolic content similar to fresh juice, indicating the absence of additional non-thermal effects. Regarding color, both treatments promoted only a slight difference by visual perception. Considering these two quality parameters, ultrasound and ohmic heating seem to be a good alternative for sugarcane juice pasteurization.


Asunto(s)
Jugos de Frutas y Vegetales/análisis , Espectrometría de Masas/métodos , Fenoles/análisis , Saccharum/química , Cromatografía Líquida de Alta Presión , Color , Flavonas/análisis , Manipulación de Alimentos , Oxidación-Reducción , Pasteurización , Saccharum/metabolismo , Estaciones del Año , Sonicación
14.
Food Chem ; 348: 129046, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-33508606

RESUMEN

Biodegradation based on microbial enzymes is considered to be one of the promising ways for controlling patulin contamination. However, few patulin degrading enzymes have been isolated and characterized until now. Here, a short-chain dehydrogenase/reductase (SDR) gene, CgSDR, was cloned from a yeast strain Candida guilliermondii, and expressed in Escherichia coli. The expression of CgSDR conferred a strong patulin tolerance and degradation ability to E. coli, and purified CgSDR could transform patulin into E-ascladiol in vitro with NADPH as a coenzyme. Moreover, addition of CgSDR at 150 µg/mL could reduce 80% of patulin in apple juice and the biodegradation process did not affect the quality of the apple juice. A molecular docking analysis and site-directed mutagenesis indicated that CgSDR might interact with patulin via VAL188 as an active binding sites. The findings provide new insights for developing enzymic formulations for mycotoxin detoxification in fruit derived products.


Asunto(s)
Jugos de Frutas y Vegetales/análisis , Malus/química , Patulina/metabolismo , Deshidrogenasas-Reductasas de Cadena Corta/metabolismo , Biodegradación Ambiental , Contaminación de Alimentos/análisis , Simulación del Acoplamiento Molecular , Patulina/aislamiento & purificación , Saccharomycetales/enzimología
15.
Food Chem ; 348: 129083, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-33517000

RESUMEN

In this study, three potential probiotic strains were selected to ferment blueberry and blackberry juices. The viable cell counts of selected strains were increased by 0.4-0.7 log CFU/mL in berry juices environments after 48-h fermentation. Meanwhile, the contents of cyanindin-3-glucoside and peonidin-3-glucoside decreased over 30%. Heatmap presented an upgrade trend of syringic acid, ferulic acid, gallic acid and lactic acid during fermentation. However, the contents of p-coumaric acid, protocatechuic acid, chlorogenic acid, critic acid and malic acid showed downgrade trend. The metabolism of phenolics probably contributed to the enhancement of the ABTS radical scavenging activity (40%-60%) in fermented berry juices. Moreover, the three strains presented different capacities on changing the quality of berry juices according to the PCA and LDA analysis. The contents of individual organic acids had positive correlations with sensory quality, especially for sourness. Overall, probiotic fermentation could improve the sensory quality of berry juices.


Asunto(s)
Bacterias/metabolismo , Arándanos Azules (Planta)/química , Fermentación , Jugos de Frutas y Vegetales/microbiología , Fenoles/análisis , Probióticos/metabolismo , Rubus/química , Antioxidantes/análisis , Bifidobacterium bifidum/metabolismo , Frutas/química , Jugos de Frutas y Vegetales/análisis , Humanos , Lactobacillus plantarum/metabolismo , Streptococcus thermophilus/metabolismo , Gusto
16.
Food Chem ; 347: 129000, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33465690

RESUMEN

In this study, the cypermethrin binding characteristics of lactic acid bacteria were investigated for the first time. Two strains, Lactobacillus plantarum RS60 and Pediococcus acidilactici D15, possessed the highest cypermethrin removal capacity and good tolerance to simulated digestive juices. They were employed for further studies on cypermethrin binding characteristics. 55.06% and 56.46% of cypermethrin were removed within 0.25 h by strains RS60 and D15, respectively. The effect of pH on binding capacity was negligible. Heat treatment enhanced cypermethrin binding rate. Moreover, inactive cells were capable of removing cypermethrin from fruit and vegetable juices, with over 60% cypermethrin reduction within 2 h. No adverse effect was found on the quality of juice during the biosorption process. Besides, these two strains also could bind other several pyrethroids and 3-phenoxybenzoic acid. These findings indicated that L. plantarum RS60 and P. acidilactici D15 may be useful to reduce cypermethrin in contaminated foods.


Asunto(s)
Lactobacillus plantarum/metabolismo , Pediococcus acidilactici/metabolismo , Piretrinas/metabolismo , Adsorción , Cromatografía Líquida de Alta Presión , Digestión , Contaminación de Alimentos/análisis , Jugos de Frutas y Vegetales/análisis , Concentración de Iones de Hidrógeno , Insecticidas/análisis , Insecticidas/aislamiento & purificación , Insecticidas/metabolismo , Lactobacillus plantarum/química , Pediococcus acidilactici/química , Piretrinas/análisis , Piretrinas/aislamiento & purificación , Temperatura
17.
Food Chem ; 340: 127919, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-32889210

RESUMEN

Non-enzymatic electrochemical sensors for the monitoring of reducing sugars in foods has great potential as a rapid in-situ detection method. This development involved the assembly of a nanoporous platinum structure on a screen-printed carbon electrode (SPCE). The modified electrode was then employed as an amperometric sensing element in a flow injection analysis (FIA) manifold. The system was successfully applied to the rapid detection of reducing sugars in potatoes, without the need for sample preparation. Optimal signals were achieved in phosphate buffer (pH 7.4) at a flow rate of 0.5 mL min-1 and an applied potential of 0.6 V. Experimental results demonstrated the sensor's long-term stability and high selectivity for reducing sugars. This method provides high sample throughput due to a rapid response time of less than five seconds. Reducing sugar values determined were in good agreement with those recorded using a commercially available enzymatic assay kit.


Asunto(s)
Técnicas Electroquímicas/métodos , Electrodos , Análisis de Inyección de Flujo/métodos , Análisis de los Alimentos/métodos , Solanum tuberosum/química , Azúcares/análisis , Carbono/química , Técnicas Electroquímicas/instrumentación , Análisis de Inyección de Flujo/instrumentación , Análisis de los Alimentos/instrumentación , Fructosa/análisis , Jugos de Frutas y Vegetales/análisis , Glucosa/análisis , Nanoestructuras/química , Platino (Metal)/química , Propiedades de Superficie
18.
Food Chem ; 340: 127922, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-32889211

RESUMEN

This study aimed to evaluate the fermentation performance of a mixture of Lactobacillus spp. in cloudy apple juices from nine cultivars. The results showed that cultivar influenced most the properties of the fermented cloudy apple juice. The fermented cloudy apple juices made from Changfu had the highest viable bacterial count and acetic acid contents (6.37 × 108 CFU/mL and 2.67 mg/mL, respectively). It also had higher sensory score, second only to Huaniu. The highest total sugar consumption, utilising fructose, glucose, and sucrose (33.07 mg/mL), was seen with Golden Delicious. Qinguan fermented cloudy apple juice had the highest contents of lactic acid (6.74 mg/mL) and total esters (921.36 µg/L); d-limonene also detected in this fermented cloudy apple juice. Of the nine cultivars examined in this study, Changfu, Qinguan, and Golden Delicious were the most suitable for producing fermented cloudy apple juice with better taste, higher viable count and more intense aroma.


Asunto(s)
Alimentos y Bebidas Fermentados/microbiología , Jugos de Frutas y Vegetales/análisis , Jugos de Frutas y Vegetales/microbiología , Malus , Ácido Acético/análisis , Carga Bacteriana , Femenino , Fermentación , Alimentos y Bebidas Fermentados/análisis , Humanos , Lactobacillus acidophilus , Lactobacillus fermentum , Lactobacillus plantarum , Masculino , Odorantes/análisis , Azúcares/análisis , Gusto , Compuestos Orgánicos Volátiles/análisis
19.
Food Chem ; 336: 127721, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32763731

RESUMEN

The major aroma-active compounds in clear red raspberry juice were identified by molecular sensory science approaches. Thirty-one aroma-active compounds were identified using detection frequency analysis and aroma extract dilution analysis. Among them, 18 volatiles with aroma activity in red raspberry were identified for the first time, while 14 volatiles with odor activity values (OAVs) ≥ 1 were confirmed as the major aroma-active compounds. Three C6 aldehydes showed the highest detection frequencies of 8, and ß-ionone exhibited the highest OAV of 9507 and flavor dilution factor of 512, which indicated that the floral and grassy note could be dominant in overall aroma. Quantitative descriptive analysis suggested that the grassy, floral, woody, and caramel-like notes can be simulated using aroma recombination model 1. Electronic nose analysis also demonstrated that model 1 had closer similarity to the original juice than others. The combination strategy used here would help improve the knowledge of red raspberry aroma.


Asunto(s)
Aromatizantes/análisis , Jugos de Frutas y Vegetales/análisis , Rubus/química , Compuestos Orgánicos Volátiles/análisis , Análisis Discriminante , Nariz Electrónica , Aromatizantes/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Norisoprenoides/aislamiento & purificación , Análisis de Componente Principal , Rubus/metabolismo , Microextracción en Fase Sólida , Compuestos Orgánicos Volátiles/aislamiento & purificación
20.
Food Chem ; 336: 127635, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32763734

RESUMEN

A one-step, highly-efficiency, and low-cost cold atmospheric pressure plasma (CAPP)-based method for obtaining safe-to-consume beetroot juice (BRJ) with enhanced nutritional quality is presented. Three reaction-discharge systems with different CAPPs were studied to check how the composition and physicochemical properties changed during CAPP treatment of BRJ. To identify reactive species occur in gas phase of applied CAPP for BRJ treatment, optical emission spectrometry was used. Finally, the cytotoxicity of so-obtained BRJ to human epithelial colorectal adenocarcinoma (Caco-2) and human non-malignant intestine microvascular endothelial cells (HIMEC) was assessed. Based on the performed analyses it was found that controlled CAPP treatment of BRJ changes the fraction pattern of elements in addition to increase the content of phenolic compound presents in BRJ. Furthermore, the defined CAPP treatment of BRJ inhibits proliferation of Caco-2 cell lines, exhibiting non-cytotoxic effect for HIMEC non-malignant endothelial cells. As a result, safe-to-consume BRJ of improved nutritional quality was produced.


Asunto(s)
Beta vulgaris/química , Industria de Procesamiento de Alimentos/métodos , Jugos de Frutas y Vegetales , Gases em Plasma , Antioxidantes/química , Presión Atmosférica , Células CACO-2 , Carbohidratos/análisis , Células Endoteliales/efectos de los fármacos , Jugos de Frutas y Vegetales/análisis , Jugos de Frutas y Vegetales/toxicidad , Humanos , Metales/análisis , Valor Nutritivo , Fenoles/análisis , Pruebas de Toxicidad
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