Pistachio Samples Research Articles

Evaluation of the effect of carboxy methyl cellulose edible coating containing Astragalus honey (Astragalus gossypinus) on the shelf-life of pistachio kernel

The aim of this study was to investigate the ability of carboxymethylcellulose (CMC) containing Astragalus honey (Astragalus gossypinus) to control rancidity and microbial spoilage of pistachio kernel during storage at room temperature without effect on their sensory properties. Pistachio kernels were coated with different Astragalus honey (0, 1 and 2%) and CMC (1%) concentrations. Samples were stored at room temperature for 120 days. Microbial and fungal counts, oxidation parameters, weight loss, and hardness of pistachio samples were increased, but moisture content and sensory scores were decreased during the storage. Pistachio kernels coated with honey (2%) and CMC (1%) had the lowest microbial and fungal counts, weight loss, peroxide, anisidine, free fatty acids, and textural hardness during the storage (P < 0.05). Pistachio kernels coated with CMC containing honey exhibited the lowest color changes. Sensory score of samples increased after coating with honey and CMC. At the end of 120 days storage, the peroxide value and free fatty acid content of the sample coated with CMC and honey (2%) were about half of what was considered an acceptable threshold. Overall, the CMC coting containing Astragalus honey could obviously extended the shelf life of pistachio kernel. However, for more details, it is recommended to investigate the shelf-life of pistachio kernel in longer period or in accelerated conditions.

Determination of uncertainty in the measurement of Aflatoxins B1 in pistachio nuts by the HPLC-FLD method

The present study defined uncertainties during Aflatoxin B1 measurements in pistachio nuts using HPLC equipped with fluorescence detector and derivatizing cell (Kobra® Cell) to increase the detector signal. The uncertainty of a method is one of the parameters required by EURACHEM/CITAC Guide, and forms part of the validation of analytical methods. Six variables affected the final value of the measured concentration, which were included in the mathematical model. The contribution index of each variable to the combined uncertainty (uc) was also calculated and analysis of the Pareto diagram showed that 80.47% of the variability was the result of the calculation and execution of the calibration curve of the Aflatoxin B1 standard, 19% was determined by the recovery rate of the pistachio sample and volumetric measurements affected the concentration to a very lesser extent. The value of expanded uncertainty in the determination of Aflatoxin B1 for pistachios was Ucx = 0.83 μg/kg.

Microwave-Assisted Extraction Coupled to HPLC-UV Combined with Chemometrics for the Determination of Bioactive Compounds in Pistachio Nuts and the Guarantee of Quality and Authenticity.

Two novel microwave-assisted extraction (MAE) methods were developed for the isolation of phenols and tocopherols from pistachio nuts. The extracts were analyzed by reversed-phase high-pressure liquid chromatography coupled with a UV detector (RP-HPLC-UV). In total, eighteen pistachio samples, originating from Greece and Turkey, were analyzed and thirteen phenolic compounds, as well as α-tocopherol, (β + γ)-tocopherol, and δ-tocopherol, were identified. The analytical methods were validated and presented good linearity (r2 > 0.990) and a high recovery rate over the range of 82.4 to 95.3% for phenols, and 93.1 to 96.4% for tocopherols. Repeatablility was calculated over the range 1.8–5.8%RSD for intra-day experiments, and reproducibility over the range 3.2–9.4%RSD for inter-day experiments, respectively. Principal component analysis (PCA) was employed to analyze the differences between the concentrations of the bioactive compounds with respect to geographical origin, while agglomerative hierarchical clustering (AHC) was used to cluster the samples based on their similarity and according to the geographical origin.

Polydopamine-coated magnetic Spirulina nanocomposite for efficient magnetic dispersive solid-phase extraction of aflatoxins in pistachio

An efficient adsorbent was synthesized and used in magnetic dispersive solid phase extraction (MDSPE) of aflatoxins B1, B2, G1, and G2 at trace levels in pistachio prior to analysis by HPLC equipped with a fluorescence detector. Spirulina (Sp) algae was first magnetized, followed by surface modification with dopamine (Dp). The adsorbent was characterized using FT-IR, XRD, FE-SEM, EDX, VSM, and BET analyses. The effects of different analytical parameters on the extraction performance were evaluated. Under optimal conditions, good limits of detection (LODs) and quantifications (LOQs) were achieved in the ranges of 0.02–0.07 and 0.06–0.21 ng g−1, respectively. The RSDs were 5.9, 6.3, 5.6, and 7.3% for AFB1, G1, B2, and G2, respectively. The proposed method was successfully used to determine AFs in pistachio samples and acceptable recoveries in the range of 72–95% were obtained.

Evaluation of the use of Ozone, UV-C and Citric acid in reducing aflatoxins in pistachio nut

The effects of gaseous ozone (O3), UV-C radiation, and citric acid (CA) on aflatoxins degradation in contaminated pistachio samples were investigated. By the evaluation of different combinations, the optimum amounts of O3, UV-C, and CA were achieved. The best treatment was a combination of the immersion of the samples in 3 N CA, 30 minutes’ exposure to O3, and 36 hours exposed to UV-C radiation, by this combination more than 90 % of aflatoxin B1 and aflatoxin B2 and more than 99 % of aflatoxin G1 and aflatoxin G2 were degraded. No significant changes were observed in total fat content, protein content, acid and peroxide content, total phenolic compounds, soluble and insoluble carbohydrates of pistachios. Also there were no significant changes between sweetness, acidity, flavor, color, and overall quality of treated and non-treated samples. The results showed that the combination of O3, UV-C, and CA was much more effective than the effect of each of them alone.

Chemometric Differentiation of Pistachios (Pistacia vera, Greek ‘Aegina’ Variety) from Two Different Harvest Years Using FTIR Spectroscopy and DRIFTS and Disk Techniques

Food quality is a topic of utmost importance as more and more emphasis is placed on quality rather than quantity of products. Previous studies have pointed out the interaction of quality with the harvest year. In this study, 22 Pistacia vera (Greek ‘Aegina’ variety) samples (11 from 2017 and 11 from 2018) were differentiated using Fourier transform infrared spectroscopy (FTIR) and (a) diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and (b) KBr/sample disk techniques. In both years, the pistachios trees’ growing followed standard cultivation methods and similar agronomic conditions. Two chemometric models were developed using partial least squares-discrimination analysis (PLS-DA). DRIFTS proved unable to statistically differentiate the samples (R2 = 0.96266, Q2 = 0.63152). On the contrary, the disk technique completely differentiated the pistachio samples (R2 = 0.99705, Q2 = 0.97719). The 1720–1800 cm−1 region mostly contributed to the discrimination. The disk-FTIR chemometric model is fast, robust, economical, and environmentally friendly for determining pistachio matrix quality.

Simultaneous multi-determination of pesticide residues in pistachio from Iran’s market: A probabilistic health risk assessment study

To protect consumers, food safety programs for pesticide residues are routinely carried out globally. This research aims to measure 25 types of pesticide residues in Iranian pistachio based on a quick, easy, cheap, effective, rugged, and safe (QuEChERS) method combined with an Ultra-High-Performance Liquid Chromatography (UHPLC) coupled with tandem mass spectrometry (MS/MS). The obtained detection limits and average recoveries were 3 μg L−1 and 80–110 % for all analytes, respectively. Analysis of pistachio samples indicated some target pesticides, including chlorpyrifos, imidacloprid, and acetamiprid, with values of 0.95 ± 0.01, 0.55 ± 0.02, and 0.51 ± 0.02 mg kg−1, respectively. The acetamiprid (53 %), fenitrothion (39 %), imidacloprid (34 %), and thiacloprid (25 %) were the frequently detected pesticides in pistachio samples. The mean residual concentration of chlorpyrifos, fenitrothion, and imidacloprid exceeded the E.U. maximum residue limit (MRL). According to the non-carcinogenic health risk assessment, HQ and THQ values were lower than one. Therefore, it was concluded that pistachio consumption did not constitute a remarkable health risk to consumers. However, due to the relatively high values assigned for chlorpyrifos, fenitrothion, and imidacloprid in pistachio samples, a regular and effective monitoring program is recommended to control pesticide utilization.

Elimination of Aspergillus flavus from Pistachio Nuts with Dielectric Barrier Discharge (DBD) Cold Plasma and Its Impacts on Biochemical Indices

In the present research, the effects of different durations (0, 15, 30, 60, 90, 120, 150, and 180 sec) of dielectric barrier discharge (DBD) cold plasma on decontaminating Aspergillus flavus, detoxifying pure aflatoxin B1 (AFB1), and the quality attributes of pistachio nuts (total phenolic content, antioxidant activity, chlorophylls, total carotenoids, instrumental color, total soluble protein, and malondialdehyde determination) were studied. The results showed that the viable spore population reduced with the increase of plasma treatment duration, so that after 180 s of the treatment, a decrease by 4 logs was observed in the spore population. Chlorophyll a and b, as well as total carotenoid levels and color parameters, decreased, which led to darker pistachio samples and intensity reduction in soluble protein content and protein bands. Plasma treatment did not alter the total phenolic content but slightly increased the antioxidant activity of pistachio nuts samples. The malondialdehyde values significantly increased all the plasma treatment durations. The maximum reduction of AFB1 was observed after 180 s of the treatment, which was 64.63% and 52.42% for glass slides and pistachio nut samples, respectively. The present findings demonstrated that cold plasma could be used as an efficient decontamination method of food products without inducing undesirable quality changes in nuts.

Bioaccessibility and Synthesis of Chronobiotics During In Vitro Gastrointestinal Digestion of Pistachio (Pistacia vera L.) to Mitigate Diseases Linked to Chronodisruption

Abstract Objectives This research aimed to evaluate the in vitro chronobiotic potential of Phyto-melatonin (PTM) during gastrointestinal digestion, its fermentative behavior (phenolic acids and other compounds), and potential production of chronobiotics (short-chain fatty acids or SCFAs production). Methods The chemical and nutraceutical composition of dry roasted and salted pistachios with seed coat (SC) (PN + SC) and without (PN) was evaluated. Both samples were digested under static in vitro simulated physiological conditions comprising oral, gastric, intestinal, and colonic stages. The PTM bioaccessibility during in vitro gastrointestinal digestion and colonic fermentation simulation was quantified. The identification and quantification of SCFAs and other colonic metabolites were conducted using SPME-GC-MS, followed by an untargeted metabolomic analysis. Results PN + SC had significantly (p &amp;lt; 0.05) lower lipids (−7.9) and protein (−1.1), but higher carbohydrate (+8.4) and total dietary fiber (+4.8) content (g/100g) than PN. PN + SC had highest content of total phenols (+42%), total flavonoids (+54%), and PMT (+21%) (p &amp;lt; 0.05) compared to PN. The bioaccessibility was low for both pistachio samples [Oral: 1.92 and 3.41%, PN + SC and PN; gastric: 0.83 and 1.63%; intestinal [60 min]: 1.79 and 2.55; colonic [6 h]: 0.32 and 0.36%). Chemo-informatics and an in silico analysis of PTM suggest that it was absorbed when chewed by the participants. The highest SCFAs were produced at 12 h during in vitro colonic fermentation for both pistachio samples, where PN + SC displayed the highest (p &amp;lt; 0.05) value (51 mmol/L), followed by PN (25.9 mmol/L). SCFAs, derived from bacterial fermentation of dietary fibers, can act as chronobiotics in peripheral clocks. The SCFAs molar ratio remained almost constant for both pistachio samples: butyric &amp;gt; propionic &amp;gt; acetic. Some metabolites with chronobiotic potential (e.g., indole, benzaldehyde, phenolic acids, and aliphatic/aromatic hydrocarbons) were detected, sample-dependent, through the untargeted metabolomics. Conclusions Pistachio's digestion increases the bioaccessibility of PTM and the biosynthesis of colonic metabolites (SCFAs, among others), all with chronobiotic potential to mitigate diseases linked to chronodisruption. Funding Sources The funding received by CONACyT/FOPES is appreciated.

Determination of Colour and Kinetic Parameter Differences Between Aflatoxin Contaminated and Uncontaminated Pistachio Nuts Using Machine Vision

Aflatoxins produced by Aspergillus species have a great important in the food industry, especially in dried nuts and fruits. Agricultural products are prone to the aflatoxins during the stages like harvesting, drying and storage. Rapid identification of aflatoxin contaminated products is of great interest to the food industry. The food companies start using screening technologies instead of human labour to become more profitable and accurate. Moreover, economical losses and diseases resulting from aflatoxin contamination are a significant problem. The objective of this study was to develop an image processing based aflatoxin contaminated in-shell pistachio nut identification system in order to separate aflatoxin contaminated pistachio nuts from the healthies one. Bright greenish yellow fluorescence (BGYF), which indicates possible aflatoxin contamination, was investigated as a discriminating factor for identification of contaminated pistachio nuts. A total of 100 pistachio nut samples (50 BGYF+ and 50 BGYF-) were evaluated. In the study, imaging algorithms were developed in order to classify the pistachio nut samples as BGYF+ and BGYF-. The colour (L*, a* and b*) and kinetic (chroma, hue angle and browning index) parameters of each pistachio nut sample were analysed and differences between them were determined statistically. Colour and kinetic parameters were also grouped and associated each other by using factor analysis method to simplify the image processing algorithm. Statistically significant differences were found for all colour and kinetic parameters between two groups. According to the factor analysis results; chroma, a* and browning index values were substantially loaded on Factor 1, while hue angle and b* were substantially loaded on Factor 2. The remaining variable L* was substantially loaded on Factor 3. In future studies, an optimized (more effective and convenient) image processing algorithm for developing a new real-time determination and separation system will be enhanced based on the statistical analysis results. The results obtained from this study will form a basis for further investigations.

An Impedance Based Electrochemical Immunosensor for Aflatoxin B1 Monitoring in Pistachio Matrices

Aflatoxins are highly toxic fungal secondary metabolites that often contaminate food and feed commodities. An electrochemical immunosensor for the determination of aflatoxin B1 (AFB1) was fabricated by immobilizing monoclonal AFB1 antibodies onto a screen-printed gold electrode that was modified with carbo-methyldextran by N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide cross-linking. An electrochemical interfacial modelling of biomolecular recognition was suggested and reasonably interpreted. Impedance technology was employed for the quantitative determination of AFB1. The limit of detection concentration of AFB1 for standard solutions and spiked pistachio samples was 0.5 ng/mL and 1 ng/mL, respectively. The immunosensor was able to successfully determine AFB1 concentrations in the range of 4.56–50.86 ng/mL in unknown pistachio samples. Comparative chromatographic analysis revealed that AFB1 concentrations that were higher than 345 ng/mL were not within the immunosensor’s upper limits of detection. Selectivity studies against Ochratoxin A and Aflatoxin M1 demonstrated that the proposed AFB1 immunosensor was able to differentiate between these other fungal mycotoxins. The novel electrochemical immunosensor approach has the potential for rapid sample screening in a portable, disposable format, thus contributing to the requirement for effective prevention and the control of aflatoxin B1 in pistachios.

Non-targeted approach to detect green pea and peanut adulteration in pistachio by using portable FT-IR, and UV–Vis spectroscopy

Pistachio is one of the most expensive nuts with having high economic importance in Turkey. It has become more prone to adulteration because of its high commodity value. Peanut with color additives and green pea are generally used to adulterate ground pistachio. Vibrational spectroscopy is a potential technique to detect adulterations in pistachio. The objective of this study was to generate a non-targeted method for portable FT-IR and UV–Vis spectrometers to authenticate pistachio and detect green pea and peanut adulterations. Pistachio granules were adulterated with green pea and peanut at different concentrations (5 to 40% w/w). Spectra were collected by a portable FT-IR spectrometer and by a conventional UV–Vis spectrometer and analyzed by Soft Independent Modeling of Class Analogy (SIMCA) to generate classification algorithms to authenticate pistachio, and Partial Least Square Regression (PLSR) to predict the concentrations of adulterants. SIMCA showed very distinct clusters for pure samples. Moreover, adulterated pistachio samples were discriminated by SIMCA even in low levels of adulteration (5%). Portable FTIR showed excellent performance (rval > 0.93) of predicting the adulterant levels with a standard error of prediction (SEP) 0.66% and 0.80% for green pea and peanut, respectively. Similarly, UV–VIS predicted (rval > 0.93) the adulterant levels with SEP 0.58% and 0.14% for green pea and peanut, respectively. The results supported that portable FT-IR, and UV–Vis units present great potential for real-time surveillance of green pea and peanut adulteration in pistachio.

A rapid method to detect green pea and peanut adulteration in pistachio by using portable FT-MIR and FT-NIR spectroscopy combined with chemometrics

In this research, the determination of green pea and peanut adulteration in pistachio by portable Fourier transform mid-infrared (FT-MIR) and Fourier transform near-infrared (FT-NIR) spectroscopy was studied. A rapid method to detect adulteration in pistachio is a necessity in the food industry because of its high commodity value and being one of the most consumed tree nuts. Pistachio nut is a target for economically motivated adulteration, and green pea, spinach, and peanut are the most seen adulterants in pistachio. Portable FT-MIR and FT-NIR spectrometers are simple, non-invasive, rapid, easy to transport, and cheaper alternatives to traditional methods, including chromatography (GC, HPLC), mass-spectroscopy (GC-MS, LC-MS) for the detection of pistachio adulteration. Powdered pistachio samples were adulterated with powdered green pea and peanut samples at different concentrations (5–40%). Spectra were collected with a portable FT-MIR and FT-NIR spectrometers and analyzed by Soft Independent Modeling of Class Analogy (SIMCA) to generate a classification model to authenticate pure pistachio, and Partial Least Square Regression (PLSR) to predict the levels of adulterants in pistachio. SIMCA provided, in both units, very distinct clusters for pure and adulterated samples with inter-class distance (ICD) over 3. Both units also showed superior performance in predicting adulterant levels with rVal>0.99, standard error of prediction (SEP) < 2.5%. Based on SIMCA and PLSR models, portable FT-NIR spectrometer provided more advantages over portable FT-MIR unit because the prediction with the FT-NIR spectrometer was more precise than the FT-MIR unit. Both portable FT-MIR and FT-NIR units can be used as alternative methods to traditional methods and showed great potential for real-time surveillance to detect green pea and peanut adulteration in pistachio.

Biocontrol potential of native yeast strains against Aspergillus flavus and aflatoxin production in pistachio

ABSTRACT Aspergillus flavus is the main aflatoxin producer in food and feed and has wide ecological niches. Contamination of food products such as pistachio nuts and aflatoxin secretion directly affects food safety and international food product trades. Abilities of 13 yeast strains isolated from 200 soil and pistachio nut samples collected in Iranian orchards to reduce the growth of A. flavus as well as aflatoxin production were assessed in dual culture, volatile and non-volatile compounds tests. The growth of A. flavus was reduced by 32–60%, 13–31% and 40–61% in dual culture, volatile and non-volatile compounds, respectively, while aflatoxin B1 production was diminished by 90.6–98.3%. Based on these assays, five yeast strains were selected for co-inoculation experiments using soil, pistachio hulls and leaf. A significant reduction in colony-forming units (CFU) ranging from 23% to 110% (p < .05) was observed. Molecular, physiological and morphological identification revealed these were strains of Pichia kudriavzevii and Lachansea thermotolerans. Aflatoxin biocontrol with yeast strains possesses many advantages including the ease of commercial production and organic application which is an environmental approach. More investigation is required to understand the efficiency of selective strains to inhibit A. flavus and aflatoxin production as well as withstand predominant abiotic stress in pistachio orchards and mass production in field application.

Combining of modified QuEChERS and dispersive liquid–liquid microextraction as an efficient sample preparation method for extraction of acetamiprid and imidacloprid from pistachio samples

In this research, for the first time, the QuEChERS was combined with the dispersive liquid–liquid microextraction based on deep eutectic solvent (QuEChERS-DES-DLLME). The method was developed for efficient extraction, clean-up and preconcentration of acetamiprid (ACE) and imidacloprid (IMI), two commonly used pesticides, from pistachio samples before their determination by HPLC–UV. The pesticides were firstly extracted from pistachio samples and cleaned-up by QuEChERS, and then their supernatant was used as a dispersant in following DLLME in order to further purification and preconcentration. The extraction solvent used in DLLME was based on deep eutectic solvents (DESs). Preparation of hydrophobic DES was done by mixing amyl alcohol as hydrogen bond donor and trioctylmethylammonium chloride (TOMAC) as hydrogen bond acceptor. Different parameters that affect the efficiency of the two steps were evaluated and optimized. Under optimal conditions, the limit of detections was 1.5 and 3.0 μg kg−1 for ACE and IMI and the limit of quantification was 1.5 and 4.5 μg kg−1 for ACE and IMI, respectively. Calibration curves were linear in the range 5.0–500 μg kg−1 with correlation coefficients higher than 0.99. Preconcentration factor for ACE and IMI was 16 and 13, respectively. The intraday and interday precisions at concentration levels of 10 and 100 μg kg−1 were less than 7.0%. Finally, applicability of the suggested method was investigated through analysis of the analytes in some pistachio samples, and the obtained relative recoveries (95.6–99.4%) were acceptable. The good sensitivity and suitable purification in the analysis of the pistachio samples, as a complex food matrix, are obtained using the proposed method by combining the advantages of QuEChERS and DLLME.

Effect of gamma irradiation on the physicochemical properties of pistachio (Pistacia vera L.) nuts

The effects of γ-irradiation at doses of 0, 1, 1.5, 2, 4, and 6 kGy on the physicochemical and sensory properties of pistachio nuts were investigated. The results showed that the total phenol content and antioxidant activity of the pistachio samples enhanced significantly with increasing γ-irradiation dose up to 2 kGy, whereas their values significantly reduced at doses of 4 and 6 kGy. A similar trend was observed for sensory attributes of pistachios and the highest scores were recorded at 2 kGy. The irradiation reduced the soluble protein content and affected the soluble protein profiles, either in the pattern or in the intensity of the protein bands. The irradiation at each dose reduced the chlorophylls and carotenoids levels, and brightness parameters of pistachios color; higher doses caused a notable loss in pigments and the pistachio became darker. The number and concentration of volatile components isolated and identified significantly exhibited with increasing the irradiation doses. The irradiation also caused the alteration of the fatty acids composition of pistachios, which was a remarkable increment in the relative amounts of saturated fatty acids and a decrement in the unsaturated fatty acids. In conclusion, the data showed dose-dependent differences in characteristics studied. Overall, it is recommended that mild γ-irradiation (≤ 2 kGy) promised the quality of pistachios without affecting the physicochemical, structural properties, and sensory acceptance.

Synthesis and application of a novel functionalized magnetic MIL-101(Cr) nanocomposite for determination of aflatoxins in pistachio samples

Herein, a novel method entitled magnetic solid-phase extraction based on MIL-101(Cr)/Fe3O4@SiO2@propylthiouracil composite was developed using the magnetite MIL-101(Cr) for separation and determination of aflatoxins (B1, B2, G1, G2) in pistachio samples. Characterization of the nanoadsorbent was conducted by various techniques such as FTIR, SEM, TEM, XRD, VSM and elemental analysis. Determination of AFs was carried out with a HPLC–fluorescence instrument. Experimental design methodology was utilized to investigate and find the optimum values of affecting parameters. Afterward, figures of merit of the new method were evaluated and LODs were attained in the range of 0.02–0.09 ng g−1 with the linearity domain of 0.1–4.0 ng g−1. Precision of the method was evaluated as RSD %, which was 6.4%-12.8% (n = 5). Eventually, MSPE method was employed for separation and determination of AFs in pistachio samples.

Rapid screening on aflatoxins’ presence in Pistachia vera nuts using diffuse reflectance infrared Fourier transform spectroscopy and chemometrics

Aflatoxin contamination in pistachios has been analyzed in this work, using Diffuse Reflectance Infrared Spectroscopy (DRIFTS) with chemometrics. Forty-nine Greek pistachio samples of different aflatoxin concentrations were classified into aflatoxin and non-aflatoxin groups using the 3035-2821, 1770-1721, 1570-1481 and 1260-1061cm-1 spectral regions in Kubelka-Munk conversion and first derivative form. A chemometric model was developed using twenty-eight samples as calibration, 11 as validation and 10 as test set. The discrimination analysis separated correctly the 100% of the calibration and the validation set and the 80% of the test set. The proposed chemometric model is simple, rapid, economical and environmentally friendly since it does not require chemical pre-treatment of the samples. It is expected that the present method may be proved useful in food industry and the inspection authorities as a rapid decision-making tool to detect batches that must be rejected and enhance consumers' protection from aflatoxin contaminated pistachios.

Determination of pesticides phosalone and diazinon in pistachio using ion mobility spectrometry

Diazinon and phosalone are two pesticides widely used in agriculture and gardening. Because the residues of these pesticides in fruits, vegetable, and environment are dangerous for human and domestic animal health, their determination in different samples is of importance. In this work, ion mobility spectrometry in positive mode was used for determination of residues of diazinon and phosalone in pistachio. The calibration curves for these pesticides were obtained using standard solutions. The detection limits of diazinon and phosalone measured by ion mobility were 0.1 and 0.5 ppm, respectively. The pistachio samples were prepared from market and a garden near Qazvin (Iran). The measurements showed that there is no detectable phosalone in the samples, however, diazinon was detected in the pistachio of the garden. The diazinon residues in the opened- and closed-shell pistachios one day after spraying were 0.071 and 0.008 mg/kg, respectively. After 5 days, the diazinon residues reach 0.004 and 0.006 mg/kg, respectively.

Evaluating Contamination Level of Raw and Roasted Nuts Distributed in Commercial Markets in Mazandaran Province, Iran

BACKGROUND:Raw and roasted nuts are one of the most popular snacks consumed in Iran but mishandling and poor storage conditions and practices may lead to promote the growth of microorganisms and foodborne intoxications and infections. OBJECTIVES:The purpose of this study was to investigate the microbial quality of raw and roasted (salted and unsalt- ed) nuts, distributed in commercial markets in Mazandaran province, Iran. METHODS:The moisture content, total colony counts, total coliform, fecal coliform, Staphylococcusaureus, and fungal contamination were evaluated according to procedures of Iran national standards. RESULTS: The moisture content of raw and roasted hazelnut, pistachio, almond, and cashew nut samples were above the standard limits. The moisture content of the raw peanuts was within the standard approved limit (maximum 9%). But the moisture content of the roasted peanut was higher than the permissible limit of 5%. For yeasts and moulds, except for all almond samples and 56% of cashew nut samples, all products tended to be loaded with unsatisfactory limits. The total viable count was within the standard limits in hazelnut, almond, and cashew nut samples (less than 4log cfu/gr). Satisfactory limits of coliforms (lower than 1log cfu/gr) were observed in all almond samples, 91.6% of hazelnut, and 16.7% of pistachio samples. No fecal coliforms were detected in samples. S.aureus contamination was observed in 6.5% of hazelnut, 8% of almond, 25% of cashew nut, and 33% of peanut samples. CONCLUSIONS: According to the findings, almond and hazelnut showed the least, and pistachio and peanut samples showed the highest microbial contamination.