Evaluation of a simple and fast method for the multi-elemental analysis in commercial fruit juice samples using atomic emission spectrometry

Matrix overcompensation calibration: A new strategy to correct matrix effects of carbon origin in multielement analysis by inductively coupled plasma mass spectrometry

BACKGROUND

Elemental analysis by inductively coupled plasma mass spectrometry (ICP-MS) may suffer from matrix effects; those caused by organic matrices cannot be corrected by internal standardization. A new strategy, matrix overcompensation calibration (MOC), was developed to correct such matrix effects.

RESULTS

Clear fruit juices were diluted 1:50 in 1 % HNO3 (v/v)- 0.5 % HCl (v/v)- 5 % ethanol (v/v). A standard series was treated likewise to construct an external calibration curve. As, Se, Cd, and Pb in juices were determined by dilute-and-shoot ICP-MS based on this MOC strategy. The results agreed with those obtained by standard addition calibration and microwave-aided digestion; data accuracy was validated by spike-recovery studies.

SIGNIFICANCE

Unlike standard addition calibration, a single external calibration curve established by MOC can be applicable to juices of diversified fruit, geographical, and manufacturer origins enhancing productivity.

Dilute-and-shoot ICPMS quantification of V, Ni, Co, Cu, Zn, As, Se, Ag, Cd, Ba, and Pb in fruit juices based on matrix overcompensation calibration

Analysis of V, Co, Ni, Cu, Zn, As, Se, Ag, Cd, Ba, and Pb in fruit juices was performed by inductively coupled plasma mass spectrometry (ICPMS) after simple 50-fold dilution in 1% (v/v) HNO3-0.5% (v/v) HCl-5% (v/v) ethanol. Ethanol was added to overwhelm native organic components and dominate matrix effects. A universal calibration curve was built based on a likewise treated reagent standard series. This new matrix overcompensation calibration (MOC) strategy was developed to effectively compensated for matrix effects of carbon origin and achieved quantitative (92.5-118.8%) recoveries comparable to those by standard addition calibration (92.1-117.8%) and microwave-aided digestion (99.3-116.8%). The LODs were 0.528, 0.204, 0.195, and 2.07 ng mL-1 for toxic elements As, Cd, Pb, and Ni, respectively, adequate for their regulatory monitoring. Ge, Rh, Tb, and Ir were used as internal standards. MOC renders a calibration curve universally applicable to any clear fruit juices of diversified crop, geographic, and manufacturer origins resulting in cost saving and enhanced productivity.

Are Chokeberry Products Safe for Health? Evaluation of the Content of Contaminants and Health Risk

The health-promoting properties of chokeberry fruit have been confirmed in numerous scientific studies. It has been shown that the consumption of these fruits, due to the high content of bioactive compounds, has beneficial effects in neurodegenerative diseases, in addition to having hypolipemic, hypotensive, hypoglycemic, and anti-inflammatory properties. However, different conditions and methods of fruit cultivation, as well as methods of juice and fiber production, may result in a high content of toxic substances, which reduce the health value of chokeberry products. Many substances are environmental pollutants. In this study, for the first time, we examined the content of toxic elements (As, Hg, Cd, Pb), nitrates, and nitrites in all chokeberry juices (organic, conventional, from concentrate, and not from fruit concentrate) without additives and in all chokeberry fibers available in Poland. In addition, risk indicators of adverse health effects were calculated. The median content of the contaminants tested in juices was 0.461 µg/kg for As, 1.170 µg/kg for Cd, 0.427 µg/kg for Hg, 1.404 µg/kg for Pb, 4.892 mg/kg for NO2-, and 41.788 mg/kg for NO3-. These values did not exceed the permissible standards for the calculated indicators. There were also no statistically significant differences in the content of Cd, Hg, and Pb, as well as nitrates (III) and nitrates (V), in the tested juices depending on the method of cultivation and juice production. However, statistically significant differences in As content were found between juices from conventional and organic cultivation (1.032 µg/kg vs. 0.458 µg/kg) and juices from concentrate and not from concentrate (1.164 µg/kg vs. 0.460 µg/kg). There were no statistically significant differences with respect to impurities in fibers. It is shown that the consumption of chokeberry juice and fiber in the amount normally consumed does not pose a health risk associated with the intake of toxic substances; in the case of long-term fiber consumption, the Pb content should be monitored. In particular, organic juices and those not from fruit concentrate are recommended due to the lower As content.

New electrolyte beverages prepared by the citrus canning processing water through chemical improvement

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Citrus segment membrane removal during canning was improved for clean process.

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The improved process using mixed acid (alkali) showed good membrane removal result.

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The processing water was fully used for preparing a new healthy electrolyte drink.

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The bioactive compounds in the canning processing water were completely recoverd.

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This green process with economic viability has great society benefits.

In the production of canned citrus, large amounts of processing water were discharged during the segment membrane removal process, causing severe pollution. In order to reduce pollution and recover the bioactive compounds in the processing water, the production of canned satsuma mandarin, sweet orange and grapefruit were studied, and improved acid (0.1% HCl, 0.4% citric acid) and alkali (0.1% KOH, 0.2% NaOH) were used to conduct the new chemical hydrolysis process to remove the segment membrane. The obtained acid and alkali processing water were firstly explored the potential to make novel beverages, which contain electrolytes (Na: 472–945 ppm; K: 208–279 ppm; Cl: 364–411 ppm; citrate: 1105–1653 ppm) and potential prebiotics such as pectin and flavonoids. The improved segment membrane removal process realized the conversion of wastewater into drinkable beverages at low costs. The bioactive compounds were fully recovered without wastewater discharging, which produced great environmental, economic and health value.

Determination of essential and non-essential element concentrations and health risk assessment of some commercial fruit juices in Turkey

Aim of present study is to quantify essential (Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, P, Se and Zn) and non-essential/toxic (Al, As, Ba, Cd, Ni, Pb and Ti) elements of 100% fruit juices (orange, apple, pomegranate and grape) and fruit nectars (orange, peach, apricot and cherry and the determination of non-carcinogenic and carcinogenic risks. For this purpose, inductively coupled plasma-optical emmision spectroscopy was used to find out element content of samples after microwave digestion process. Essential element contents of 100% fruit juices and nectars were determined as max. 1350 mg/L (K, in 100% orange juice) and min. 0.007 mg/L (Cr, in 100% grape, cherry and apricot nectar and Cu, Mo, in 100% apple juice). Furthermore, the daily intake percentages of essential elements were calculated for 200 mL fruit juice consumption. Target hazard quotients, hazard indexes (HI) and target carcinogenic risks (TR) of non-essential, trace and ultra trace elements were also calculated and risk analysis were conducted. According to the results, the HI and TR of samples were founded as less than 1 and 1 × 10^-4, respectively. All samples evaluated as in the low risk group.

Evaluation of Copper and Manganese Concentrations in Commercial Fruit Juices and Nectars Consumed in Brazil by GF AAS

The present work proposes a simple method for direct determination of Cu and Mn in commercial fruit juices and nectars by graphite furnace atomic absorption spectrometry (GF AAS). We analyzed samples of different flavors (orange, mango, passion fruit, peach, and grape) and brands of Brazilian commercial fruit juices and nectars. We also carried out a study to define a suitable temperature program and to optimize the calibration conditions. It was possible to determine Cu and Mn in the samples just after a simple dilution of samples with a 0.70 mol L^-1 HNO₃ solution, except in the case of grape juice. We compared the results obtained with the proposed method to those obtained after a traditional treatment based on acid digestion in a microwave oven, and no significant differences were observed (except for grape juice). The accuracy of the method was assessed through a recovery test, which provided recovery percentages in the range of 81-117%. Precision was always better than 8%, and the limits of quantification for Cu and Mn were 6 μg L^-1 and 9 μg L^-1, respectively. We analyzed twenty-two samples, and the concentrations of Cu and Mn were in the range of 24.1-321 μg L^-1 and 116-3296 μg L^-1, respectively. Statistical analysis using a two-way analysis of variance (ANOVA) at 95% confidence level showed that flavor and brand impacted on the concentration of the analytes in the samples. Among the samples analyzed, the grape juice presented the highest concentrations of both Cu and Mn.

Determination of nutrients in sugarcane juice using slurry sampling and detection by ICP OES

The fractional factorial and Doehlert designs for optimization of a slurry sampling procedure to determine of nutrients in sugarcane juice by inductively coupled plasma optical emission spectrometry (ICP OES) were applied. External calibration curves were used for direct analysis of the slurry. This procedure allowed determination of Ca, Cu, Fe, K and Mg with limits of detection (LoD) obtained of 2.0, 0.04, 0.2, 1.0 and 1.5 mg L^-1, respectively. The precision was expressed as relative standard deviation (%RSD), being better than 1.4% (n = 3). Accuracy was confirmed by comparison with sample digestion method. The results for analysis of fourteen sugarcane juices samples demonstrated that the nutrients Ca, Cu, Fe, K and Mg have average contents of 108, 0.506, 6.40, 470 and 114 mg L^-1, respectively. The proposed analytical method is a good alternative for simultaneous determination of nutrients in sugarcane juice using introduction of slurries and detection by ICP OES.

Determining the geographical origin of Sechium edule fruits by multielement analysis and advanced chemometric techniques

This paper describes the determination and evaluation of the major and trace element composition (Al, As, Ba, Ca, Cd, Co, Cu, Fe, K, Mg, Mn, Na, Pb, Sr and Zn) of Sechium edule (Jacq) Swartz fruits collected from four different places of production in Corrientes province, Argentina. Element concentrations were determined by using inductively coupled plasma optical emission spectrometry (ICP OES) after microwave digestion. The accuracy was confirmed with standard reference material of spinach leaves (NIST, 1570a) and spiking tests. Principal component analysis (PCA), linear discriminant analysis (LDA), k-nearest neighbors (kNN), partial least square-discriminant analysis (PLS-DA) and support vector machine (SVM) were applied to the results for discriminating the geographical origin of S. edule fruits. Finally, the LDA method was found to perform best with up to 90% accuracy rate based on the following elements: Ca, Ba, Cu, Mn, Na, Sr, and Zn.