Titanium dioxide is a common additive in many food, personal care, and other consumer products used by people, which after use can enter the sewage system and, subsequently, enter the environment as ...treated effluent discharged to surface waters or biosolids applied to agricultural land, incinerated wastes, or landfill solids. This study quantifies the amount of titanium in common food products, derives estimates of human exposure to dietary (nano-) TiO2, and discusses the impact of the nanoscale fraction of TiO2 entering the environment. The foods with the highest content of TiO2 included candies, sweets, and chewing gums. Among personal care products, toothpastes and select sunscreens contained 1% to >10% titanium by weight. While some other crèmes contained titanium, despite being colored white, most shampoos, deodorants, and shaving creams contained the lowest levels of titanium (<0.01 μg/mg). For several high-consumption pharmaceuticals, the titanium content ranged from below the instrument detection limit (0.0001 μg Ti/mg) to a high of 0.014 μg Ti/mg. Electron microscopy and stability testing of food-grade TiO2 (E171) suggests that approximately 36% of the particles are less than 100 nm in at least one dimension and that it readily disperses in water as fairly stable colloids. However, filtration of water solubilized consumer products and personal care products indicated that less than 5% of the titanium was able to pass through 0.45 or 0.7 μm pores. Two white paints contained 110 μg Ti/mg while three sealants (i.e., prime coat paint) contained less titanium (25 to 40 μg Ti/mg). This research showed that, while many white-colored products contained titanium, it was not a prerequisite. Although several of these product classes contained low amounts of titanium, their widespread use and disposal down the drain and eventually to wastewater treatment plants (WWTPs) deserves attention. A Monte Carlo human exposure analysis to TiO2 through foods identified children as having the highest exposures because TiO2 content of sweets is higher than other food products and that a typical exposure for a US adult may be on the order of 1 mg Ti per kilogram body weight per day. Thus, because of the millions of tons of titanium-based white pigment used annually, testing should focus on food-grade TiO2 (E171) rather than that adopted in many environmental health and safety tests (i.e., P25), which is used in much lower amounts in products less likely to enter the environment (e.g., catalyst supports, photocatalytic coatings).
•Development and validation of a qualitative screening method for pesticides.•Investigations why the validation criteria were not fulfilled for many analytes.•Matrix effects affect analytes with ...similar retention times in a different way.•In-source collision induced dissociation attenuates signal intensities and provides additional criteria for identification.
Because of the high number of possible pesticide residues and their chemical complexity, it is necessary to develop methods which cover a broad range of pesticides. In this work, a qualitative multi-screening method for pesticides was developed by use of HPLC-ESI-Q-TOF. 110 pesticides were chosen for the creation of a personal compound database and library (PCDL). The MassHunter Qualitative Analysis software from Agilent Technologies was used to identify the analytes. The software parameter settings were optimised to produce a low number of false positive as well as false negative results. The method was validated for 78 selected pesticides. However, the validation criteria were not fulfilled for 45 analytes. Due to this result, investigations were started to elucidate reasons for the low detectability. It could be demonstrated that the three main causes of the signal suppression were the co-eluting matrix (matrix effect), the low sensitivity of the analyte in standard solution and the fragmentation of the analyte in the ion source (in-source collision-induced dissociation). In this paper different examples are discussed showing that the impact of these three causes is different for each analyte. For example, it is possible that an analyte with low signal intensity and an intense fragmentation in the ion source is detectable in a difficult matrix, whereas an analyte with a high sensitivity and a low fragmentation is not detectable in a simple matrix. Additionally, it could be shown that in-source fragments are a helpful tool for an unambiguous identification.
The analysis of food components using capillary electromigration methods is reviewed in this work. Papers that were published from February 2009 to February 2011 are included following the previous ...review by Herrero et al. (Electrophoresis, 2010, 31, 205–228). The analysis of amino acids, biogenic amines, peptides, proteins, DNAs, carbohydrates, phenols, polyphenols, pigments, toxins, pesticides, vitamins, additives, small organic and inorganic ions and other compounds found in foods and beverages are reviewed, as well as those applications of CE for monitoring food interactions and food processing. The use of microchips, CE‐MS and chiral‐CE in food analysis is also discussed as well as other current and foreseen trends in this area of research including new developments in Foodomics.
•Chemical characterization and biological activity of 7 honey types was evaluated.•Honeydew honeys have significant antioxidant activity.•All tested honeys exhibited antibacterial activity.•Botanical ...and geographical origin are crucial for elemental composition.
A chemical characterization and biological activity of 7 honey types (multifloral, linden, rapeseed, sunflower, phacelia, acacia and honeydew honey) from different regions of Serbia were presented. The physicochemical characteristics, mineral content, antioxidant and antimicrobial activity were estimated and discussed. All honeys showed good nutritional characteristics, according to the adopted criteria of the standard codex for honey. The concentrations of 15 elements in honey samples were determined using inductively coupled plasma optical emission spectroscopy (ICP-OES). Limits of quantification were in the range from 0.003 mg/kg (Cd, Cr, Cu, Mn, and Pb) to 1.50 mg/kg for sodium. Precision was expressed as relative standard deviation and its values were lower than 1.50%. Accuracy was evaluated with certified reference material (fish protein, DORM 4, NRC and cooking chocolate, SRM 2384, NIST) and obtained recovery percentages were 71-127%. The content of the most abundant elements (K, Mg, and Na) and microelements (Al, Cu, Fe, Mn, Ni, Se, Si, and Zn) showed a significant variability in accordance of their botanical and geographical origin, but also the influence of harvest conditions. The levels of toxic metals (As, Cd, Cr, and Pb) are much lower than the maximal allowed for these metals according to European Commission Regulation. The antioxidant activity was evaluated by DPPH (Diphenylpicrylhydrazyl) assay while antimicrobial activity against Gram positive and Gram negative bacteria (E. coli and S. aureus) and fungi Candidi albicans was estimated by microdilution assay. The free radical scavenging assay (%RSA) varies significantly among the honey samples. The highest antioxidant activity was observed with honeydew honeys (over 75% RSA) and the lowest was observed in the acacia, ranging from 22.96 to 24.57% RSA. All honeys tested in this study exhibited antibacterial activity, with inhibition of bacterial growth, generally the higher against E. coli (80% for linden honeys) than against S. aureus (mostly much lower than 50%). Activity against Candidi albicans was almost negligible. The dataset composed of all experimental results was subjected to a chemometric evaluation and cluster analysis as hierarchical nonsupervised method was applied. According to the obtained outcome of applied algorithms, both botanical and geographical origin have important role in the elemental composition, antioxidant and antimicrobial activities.
•Application potential of molecularly imprinted polymers (MIP) in food safety.•MIPs-based sample preparation and sensors detection of chemical residues in food.•Application of MIPs in chromatographic ...stationary phase.•Challenges and countermeasures of MIP in food analysis.
Due to the extensive use of chemical substances such as pesticides, antibiotics and food additives, food safety issues have gradually attracted people's attention. The extensive use of these chemicals seriously damages human health. In order to detect trace chemical residues in food, researchers have to find several simple, economical and effective tools for qualitative and quantitative analysis. As a kind of material that specifically and selectively recognize template molecules from real samples, molecular imprinting technique (MIT) has widely applied in food samples analysis. This article mainly reviews the application of molecularly imprinted polymer (MIP) in the detection of chemical residues from food in the past five years. Some recent and novel methods for fabrication of MIP are reviewed. Their application of sample pretreatment, sensors, etc. in food analysis is reviewed. The application of molecular imprinting in chromatographic stationary phase is referred. Additionally, the challenges faced by MIP are discussed.
Astringency and bitterness are organoleptic properties widely linked to tannin compounds. Due to their significance to food chemistry, the food industry, and to human nutrition and health, these ...tannins' taste properties have been a line of worldwide research. In recent years, significant advances have been made in understanding the molecular perception of astringency pointing to the contribution of different oral key players. Regarding bitterness, several polyphenols have been identified has new agonists of these receptors. This review summarizes the last data about the knowledge of these taste properties perceived by tannins. Ultimately, tannins' astringency and bitterness are hand-in-hand taste properties, and future studies should be adapted to understand how the proper perception of one taste could affect the perception of the other one.
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•Green chemistry approach based on Silver nanomaterial and deep eutectic solvent.•Selective lead extraction from edible oil.•Significant improvement in method performance.•Lead ...analysis in edible oil at µg/L (ppb) level using a green solvent.
This paper presents an application of silver nanoparticles impregnated by Deep Eutectic Solvents (DES) as ultrasonication aided microextraction system for lead (II) determination in edible oils. The paper presents a systematic optimization of method parameters and examples of its application for analysis of real samples. Maximum recovery for lead (II) extraction was obtained for choline chloride and phenol with a 1:2 M ratio. Optimum extraction conditions for 2 g oil sample post-digested solution (10 mL, pH = 2) require 1 mL of Ag-nanoparticles solution (0,1mM) and per each 500 µL of DES and tetrahydrofurane. The limit of detection (LOD) and quantification (LOQ) were 0.28 µg/L and 0.94 µg/L. The developed method covers the entire range of expected levels of lead concentration in oil samples -parts per billion levels to higher ones. This method is many folds faster (only 6.5 min/sample are needed) as well as more sensitive comparing to already reported methods.
Elicitation is a good strategy to induce physiological changes and stimulate defense or stress-induced responses in plants. The elicitor treatments trigger the synthesis of phytochemical compounds in ...fruits, vegetables and herbs. These metabolites have been widely investigated as bioactive compounds responsible of plant cell adaptation to the environment, specific organoleptic properties of foods, and protective effects in human cells against oxidative processes in the development of neurodegenerative and cardiovascular diseases and certain types of cancer. Biotic (biological origin), abiotic (chemical or physical origin) elicitors and phytohormones have been applied alone or in combinations, in hydroponic solutions or sprays, and in different selected time points of the plant growth or during post-harvest. Understanding how plant tissues and their specific secondary metabolic pathways respond to specific treatments with elicitors would be the basis for designing protocols to enhance the production of secondary metabolites, in order to produce quality and healthy fresh foods.
Fresh tea leaves (Camellia sinensis (L.) O. Kuntze) are processed by various techniques to produce different types of tea. The most common way to classify tea types is based on the similarities in ...processing methods resulting in the five commonly recognized tea types: white, green, oolong, black, and pu‐erh teas. The differences in the degree and nature of fermentation of tea leaves lead to different chemical changes depending on the processing method. Understanding the phytochemical profile of differently processed tea is important, as tea types classified by processing methods are currently not well defined because the chemical parameters for these tea types are still not established. Therefore, any significant characteristics found for a tea type due to processing may be helpful in defining tea types. However, the evidence on the impact of tea processing on phytochemical profile and contents in differently processed tea is currently unclear. Therefore, this review aims to examine (1) the processing techniques of white, green, oolong, black, and pu‐erh tea, (2) the impact of tea processing on tea phytochemicals, and (3) the key characteristics associated with the phytochemical profiles of differently processed tea.
Practical Application
Tea (Camellia sinensis (L.) O. Kuntz) is the most widely consumed beverage in the world. Tea consumption has been demonstrated through in‐vitro experiments and in animal and human intervention studies to exhibit potential in preventing various oxidative stress‐related chronic diseases, such as cardiovascular diseases, Alzheimer.s disease, diabetes and certain cancers. Based on the processing methods, tea is commonly categorized into white, green, oolong, black and pu‐er tea. However, there are large overlap in processing methods between some teas and, more importantly, the chemical compositions of differently processed teas are highly variable. This review aims to examine (1) how white, green, oolong, black and Pu‐erh tea are processed, (2) what are the effects of tea processing on tea phytochemicals and (3) to identify whether there are key characteristics associated to the phytochemical profiles of differently processed teas. The review will contribute to tea research in collating in one article the state of knowledge on the chemical changes and composition of the differently processed teas, and point to future direction in this area of research.
•Two Euterpe species can produce the acai fruit.•Euterpe oleraceae and E. precatoria are endemic from different Amazonian regions.•Exploration and consumption have been changing the region and ...production species.•Chemical composition and pharmacological properties are different at the two plants.•This review is focused on the last 5years of the scientific literature.
Acai (acai or assai) is one of the Amazon’s most popular functional foods and widely used in the world. There are many benefits to its alleged use in the growing market for nutraceuticals. The acai extracts have a range of polyphenolic components with antioxidant properties, some of those present in greater quantity are orientin, isoorientin and vanillic acid, as well as anthocyanins cyanidin-3-glucoside and cyanidin-3-rutinoside. The presence of these substances is linked mainly to the antioxidant, anti- inflammatory, anti-proliferative and cardioprotective activities. Importantly, there are two main species of the Euterpe genus which produce acai. There are several differences between them but they are still quite unknown, from literature to producers and consumers. In this review are highlighted the chemical composition, botanical aspects, pharmacological, marketing and nutrition of these species based on studies published in the last five years in order to unify the current knowledge and dissimilarities between them.
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