On-Chip Capture, Raman-Silent Polymer Labeling, and Digital Mapping Analysis of Escherichia coli O157:H7 in Beverages All-in-One.

Escherichia coli O157:H7 is one of the most susceptible foodborne pathogens, easily causing food poisoning and other health risks. It is of great significance to establish a quantitative method with higher sensitivity and less time consumption for foodborne pathogens analysis. The Raman-silent signal has a good performance for avoiding interference from the food matrix so as to achieve accurate signal differentiation. In this work, we presented a preparation-mapping all-in-one method for digital mapping analysis. We prepared a functionalized Raman-silent polymer label of Escherichia coli O157:H7, which was captured on a porous 4-mercaptophenylboric acid@Ag foam chip. To improve accuracy and widen the detection range, a digital mapping quantitative strategy was employed in data extraction and processing. By transfer mapping information into digitized statistical results, the limitation of obtaining reproducible intensity values just by randomly selected spots on the substrate can be addressed. With a wide linear range of 1.0 × 101-1.0 × 105 CFU mL-1 and a limit of detection of 4.4 CFU mL-1, this all-in-one method had good sensitivity performance. Also, this method achieved good precision and selectivity in a series of experiments and was successfully applied to the analysis of beverage samples.

Impact of acidic beverages on composition and surface characteristics of human teeth: scanning electron microscopic, stereomicroscopic and energy dispersive x-ray analyses.

OBJECTIVES: The objective of this study was to evaluate the effect of acidic beverages on the surface topography and elemental composition of human teeth. METHODS: A total of five highly acidic beverages (Red Bull, Pepsi, Apple Cidra, Tang Mosambi, and Tang Orange) were investigated. The tooth specimens of experimental groups were submerged in each beverage and incubated at 37 °C for 7 days, whereas, the tooth specimens of control groups were placed in distilled water. Afterwards, tooth specimens were analyzed using scanning electron microscopic (SEM), stereomicroscopic, and energy dispersive x-ray (EDX) techniques. RESULTS: All experimental groups revealed a decline in the tooth elements compared to controls, however, such decline was not statistically significant. Nevertheless, comparing the experimental groups, the Red Bull beverage caused a marked reduction in the percentage of both calcium and phosphorus elements compared to the Pepsi, Apple Cidra, Tang Mosambi, and Tang Orange beverages but it was insignificant as well in contrast to its control counterpart. All five acidic beverages demonstrated erosive potential under SEM analysis; however, each group of specimens showed a diverse amount of demineralization. In addition, all experimental groups exhibited significant discoloration of tooth specimens compared to their respective control counterparts. CONCLUSIONS: Within the limitations of study, all five acidic beverages demonstrated erosive potential in the simulated in vitro conditions under SEM analysis; however, each group of specimens exhibited a different extent of demineralization. In addition, the overall effect of all beverages was insignificant under EDX analysis as no substantial difference was revealed between the elemental composition of experimental and control group specimens.

Βisphenol A and its analogs migrated from contact materials into food and beverages: An updated review in sample preparation approaches.

Bisphenols are used as monomers in the production of plastic materials, and they are likely to be detected in food contact materials. Due to their migration from these plastic packaging materials into food and beverages, the organoleptic properties of the products are changing and plenty of harmful effects on human health are caused, especially if consumers are exposed to higher levels of bisphenols than those established by legislation. However, because of their trace-level presence, their determination into food and beverage matrices is rather difficult. For this reason, sensitive, simple, rapid, and green methods are required to extract and preconcentrate the analytes of interest. Effective and representative tests are required as well, to evaluate the migration of bisphenols from plastic materials under realistic usage conditions. This review provides a detailed background of bisphenol A chemistry and legislation. Furthermore, it refers to bisphenol A migration test procedures and the recent advances of the last decade in the extraction of bisphenols from various matrices by using different sample preparation techniques prior to their chromatographic determination.

Development of a polyurethane-coated thin film solid phase microextraction device for multi-residue monitoring of pesticides in fruit and tea beverages.

A novel solid-phase microextraction device coated with an efficient and cheap thin film of polyurethane was developed for trace determination of 13 widely used pesticides in fruit and tea beverages. A round-shaped polyurethane film covering the bottom of a glass vial was fabricated as the sorbent to exhibit a superior capacity for preconcentrating target compounds and reducing matrix interferences. After optimization of the key parameters including the film type, extraction time, solution pH, ionic strength, desorption solvent, and conditions, this device allowed an efficient adsorption-desorption cycle for the pesticides accomplished in one vial. Coupled with gas chromatography-electron capture detection, the polyurethane-coated thin film microextraction method was successfully established and applied for the analysis of real fruit and tea drinks, showing low limits of detection (0.001-0.015 µg/L), wide linear ranges (1.0-500.0 µg/L, r2  > 0.9931), good relative recoveries (77.2%-106.3%) and negligible matrix effects (86.1%-107.5%) for the target pesticides. The proposed approach revealed strong potential of extending its application by flexibly modifying the type or size of the coating film. This study provides insights into the enrichment of contaminants from complex samples using inexpensive and reusable microextraction devices that can limit the environmental and health impact of the sample preparation protocol.

Antimony in Polyethylene Terephthalate-Bottled Beverages: The Migration Puzzle.

A novel strategy to assess the main variables that potentially affect the migration of antimony from PET bottles to beverages, including mineral waters and juices, is herein proposed. In a preliminary step, an LC-ICP-MS method previously used for water analysis was optimized to correct identify Sb species present in the studied matrices using HRMS. Subsequently, the influence of temperature and storage time up to 30 days on Sb migration from PET bottles into peach and pineapple juices of the same brand was studied. Storing PET bottled drinks at elevated temperatures (i.e., in a hot car or in summer) can cause antimony migration to exceed the limits allowed in the EU or USA. Because the behavior observed differed from the results reported for Sb migration in mineral waters, a second approach was proposed: three mineral water and two juice samples were kept in different PET containers and stored at an elevated temperature (up to 60 °C) to understand the role of the PET type and matrix simultaneously. This study demonstrated that both matrix characteristics and type of PET bottle greatly influence antimony leaching, highlighting the need to consider these variables together when conducting migration experiments. The obtained results can be helpful for developing future legislation concerning migration of pollutants from packing to food commodities.

Recycling of polypropylene by supercritical carbon dioxide for extraction of contaminants from beverage cups. A comparison with polyethylene terephthalate and polylactic acid.

BACKGROUND: EU policies towards a circular economy address plastic packaging as one of the significant concerns and sets ambitious recycling targets. Polyolefins (POs) cannot be recycled for food contact using conventional polyethylene terephthalate (PET) recycling approaches. Thermal degradation prevents the use of high temperatures and, consequently, decontamination of POs may be insufficient when using lower temperatures. Polypropylene (PP) beverage cups were decontaminated using supercritical fluid extraction with carbon dioxide (scCO2 ). Decontamination efficiencies (DEs) of selected markers were determined in challenge tests following European Food Safety Authority guidelines. The effects of time (10-60 min) for PET, polylactic acid (PLA), and PP and temperature (60-80 °C) for PP were studied at constant pressure. The physical properties, sensorial properties, and overall migration of treated scCO2 PP were analysed and compared with virgin PP. RESULTS: PP showed the highest average DE, and PET the lowest, for all the surrogates and in all time conditions. A relative increase in the DE with the increase in process time, particularly for PET and to some extent for PLA, was seen. For PP, no significant impact of time and temperature was observed under the conditions tested. The DE of volatile surrogates was higher than that of semi-volatiles. Results indicate that the scCO2 treatment did not affect the physical and sensorial properties, nor the overall migration of PP, although it contributes to a considerable reduction in extractable n < C24 alkanes. CONCLUSIONS: Results indicate that scCO2 can be used to decontaminate post-consumption PP beverage cups with higher DEs than those for PET and PLA, applying mild processing conditions. © 2022 Society of Chemical Industry.

Millennial drinks: acidity, fluoride content, and enamel softening.

This in vitro study aimed to evaluate the acidity and fluoride content of beverages commonly consumed by millennials and the enamel-softening effect of these drinks on tooth enamel. The study included 13 beverages in 4 categories: energy (sports) drink, flavored sparkling water, kombucha, and other (an unsweetened iced tea, a vegetable-fruit juice blend, and a soft drink). The acidity was measured with a pH/ion meter, and the fluoride concentration was measured with a combined fluoride electrode coupled to the meter (n = 10 measurements per beverage). The Vickers hardness number of extracted molars was measured before and after a 30-minute immersion in 4 representative beverages via 2 immersion protocols (n = 10 per beverage per protocol): (1) immersion in the beverage only and (2) immersion alternating between the beverage and artificial saliva every other minute. The pH and fluoride concentrations of the beverages ranged from 2.652 to 4.242 and from 0.0033 to 0.6045 ppm, respectively. One-way analysis of variance (ANOVA) revealed that all differences between beverages in pH values were statistically significant, as were the majority of differences in fluoride concentrations (P < 0.001). The beverages and the 2 immersion methods significantly affected enamel softening (2-way ANOVA, P = 0.0001 to 0.033). The representative energy drink (pH 2.990; 0.0102 ppm fluoride) caused the greatest enamel softening followed by the representative kombucha (pH 2.820; 0.2036 ppm fluoride). The representative flavored sparkling water (pH 4.066; 0.0098 ppm fluoride) caused significantly less enamel softening than the energy drink and kombucha. A root beer (pH 4.185; 0.6045 ppm fluoride) had the least enamel softening effect. All tested beverages were acidic and had a pH below 4.5; only some contained fluoride. Flavored sparkling water, likely due to its higher pH, caused less enamel softening than the tested energy drink and kombucha. The fluoride content of kombucha and root beer lower their enamel-softening effects. It is imperative that consumers be aware of the erosive potential of beverages they consume.

Analysis of Erosive Nature of Fruit Beverages Fortified with Calcium Ions: An In Vitro Study Evaluating Dental Erosion in Primary Teeth.

Background: Since children frequently consume acidic fruit beverages, dental erosion is common in children. The erosive effects on primary teeth are more profound due to the lesser thickness of enamel and dentin. This study evaluated if calcium fortification of fruit beverages could reduce their erosive potential. Methodology. Tropicana Orange Delight was the fruit beverage chosen and fortified with calcium carbonate. Forty noncarious extracted primary teeth were equally distributed into four groups. Samples in group A were exposed to calcium-fortified fruit beverages and group B to nonfortified fruit beverages for 1, 2, and 3 min. The pH and calcium ion concentration of both the fruit beverages were evaluated from baseline through the test period. Samples in groups C and D were then exposed to fortified and nonfortified fruit beverages for 10, 20, and 30 min. The surface roughness and microhardness of these samples were analysed. Results: Due to fortification, the pH and calcium ion concentration of fortified beverages was higher compared to nonfortified beverages at baseline. The calcium ion concentration of fortified beverages decreased from baseline in contrast to an increase in the nonfortified beverage group. This indicates that fortified beverage is less erosive in nature. The surface roughness of samples in the fortified beverage group did not decrease significantly from baseline. In the nonfortified beverage group, surface roughness values at 20 and 30 min of exposure were higher than baseline, suggesting that significant erosive changes occur at the prolonged duration of exposure. The microhardness values of samples in the fortified beverage group increased from baseline through the test period, suggestive of resistance to erosion offered by calcium fortification. The microhardness values of samples in the nonfortified beverage group decreased through the test period, suggestive of erosion. Conclusion: Calcium fortification of this fruit beverage significantly reduces its erosive potential on primary teeth.

Association of oral microbiota profile with sugar-sweetened beverages consumption in school-aged children.

Evidence that common beverage consumption is associated with oral ecosystem. However, little is known about the effect of sugar-sweetened beverages (SSBs) on composition and functional potential of childhood oral microbiota. We aim to examine associations between SSBs consumption with oral microbiota diversity and function among school-aged children. Oral microbiota in buccal swab samples was collected from 180 children (11.3 ± 0.6 years) from an ongoing child growth and development cohort established in 2016, using 16S rDNA gene sequencing. Higher SSBs consumption (≥1 serving/day) was associated with lower oral microbiota richness and diversity. Children with higher SSBs consumption showed decreased abundance of genus Fusobacterium, Lachnoanaerobaculum, Soonwooa, Tannerella and Moraxella (p < 0.05). However, more SSBs intake selectively increases the dominance of aciduric bacteria (Neisseria and Streptococcus), which can lead to dental caries and other oral problems. Furthermore, PICRUSt analysis illustrated that oral microbiota was more conducive to the pathway activated of protein export (p = 0.020), D-glutamine and D-glutamate metabolism (p = 0.013), and pantothenate and CoA biosynthesis (p = 0.004), indicating vigorous microbial metabolism in oral bacterial community in higher SSBs intake groups. Overall, our finding suggests that higher SSBs consumption may disturb oral microecology and reduce diversity of microbiota during childhood, stimulating an increase in cariogenic genera, which contributes to increased susceptibility of SSBs-related oral diseases.

Melanoidins present in traditional fermented foods and beverages.

Traditional fermented foods and beverages (TFFB) are an important dietary component consumed in large quantities worldwide. Currently, much attention has been focused on the health benefits of TFFB. Melanoidins, a class of bioactive substance produced in the final stage of the Maillard reaction, not only have a significant impact on sensory properties of TFFB but also contribute to the health effects. Melanoidins formed in the fermentation system with a long reaction time at low temperature could be different from those obtained from high-temperature, short-duration roasted systems due to the multiple formative stages and involvement of microorganisms and enzymes. In this paper, the current state of knowledge regarding the formation, distribution, extraction and purification, physicochemical properties, structure characteristics, and biological activities of TFFB melanoidins are comprehensively reviewed, with predominant focus on TFFB that are typically brown like douchi, miso, cheonggukjang, soy sauce, huangjiu (Chinese rice wine), beer, vinegar, and sweet wine. The current challenges and prospective recommendations for the research of melanoidins in fermented systems are also presented. In future, people should pay more attention to the basic research on TFFB melanoidins, especially purification methods and formation mechanisms, further substantiation of health properties of TFFB melanoidins in vivo, and development of specific melanoidins to fulfill technological, productive, or health needs of consumers.

[Technological features of fermented beverages production using kombucha].

Kombucha is a beverage made by fermenting sweetened brewed tea (substrate) by symbiotic culture of yeast and bacteria. Numerous researches on optimization of fermentation process, determination of the influence of technological factors on physical and chemical properties, formation of taste and flavor profile of the beverages, prevention of industrial product risks are due to the growing popularity of kombucha in Europe and the USA. Technological features of kombucha production are to optimize conditions for the growth of symbiotic culture and substrate fermentation. The duration of the process depends on the composition of the substrate, the ratio of tea mushroom and substrate, temperature, size and shape of fermentation vessel. The aim of the work was to generalize the results of studying the technological features of the production of fermented kombucha type beverages and to identify the factors that affect the chemical composition and safety of the finished beverages. Material and methods. Analytical research was carried out on the main databases for the keyword "kombucha". The criteria for inclusion of articles in the analysis were research articles with open access and presenting detailed technology of kombucha. Results. The technology of kombucha production is based on fermentation of the substrate and obtaining the base of the beverage with high content of organic acids, mainly acetic acid. In order to ensure microbiological safety the acetic acid concentration in the beverage base must be at least 1.2%. The high organic acid content necessitates the use of only glass or stainless steel fermentation equipment approved for food contact. The fermentation temperature ranges from 18 to 32 °C. The fermentation process is monitored according to basic criteria: temperature, pH value, acidity, acetic acid content, ethyl alcohol content, and residual sugar content. Kombucha production process is connected with microbiological, chemical and physical risks which could appear in case of using low quality raw materials, equipment and consumer packaging made of materials which do not correspond to sanitary norms, violating technological regimes, storage conditions of raw materials and ready production. To prevent hazards affecting the quality and safety of the finished product, it is necessary to control the technological process at all stages of production. Conclusion. Following sanitary-hygienic norms and technological regimes allows producing kombucha with a balanced taste and aroma, which meets the safety requirements for fermented beverages.

Fabrication of carbonyl-functional hypercrosslinked polymers as solid-phase extraction sorbent for enrichment of chlorophenols from water, honey and beverage samples.

Three carbonyl-functional novel hypercrosslinked polymers (HCP-TPS, HCP-TPA, and HCP-TPP) were successfully fabricated through an one-step Friedel-Crafts acylation reaction by copolymerizing paraphthaloyl chloride with triphenylsilane, triphenylamine, and triphenylphosphine, respectively. The resultant HCPs contained plenty of carbonyl-functional groups. Among the series of such HCPs, HCP-TPS displayed the best adsorption capability to chlorophenols (CPs), and thus it was employed as solid-phase extraction (SPE) adsorbent for enrichment of chlorophenols from water, honey, and white peach beverage prior to determination by high-performance liquid chromatography. Under the optimal conditions, the detection limits of the method (S/N = 3) were 0.15-0.3 ng mL-1 for tap water and leak water, 2.5-6.0 ng g-1 for honey sample and 0.4-0.6 ng mL-1 for white peach beverage sample. The recoveries of CPs in the spiked water, honey samples, and white peach beverage were in the range of 89.0-108.4%, 81.4-118.2%, and 85.0-113.5%, respectively. This work provides a new strategy for constructing functionalized HCPs as efficient SPE adsorbents. In this work, three novel hypercrosslinked polymers (HCPs) were synthesized by the Friedel-Crafts alkylation reaction (paraphthaloyl chloride as the alkylating agent, triphenylsilane, triphenylamine, and triphenylphosphine as the aromatic units). Then, HCP-TPS was applied to soild-phase extraction sorbent for enrichment CPs from water, honey, and white peach beverage samples.

New application of a traditional method: colorimetric sensor array for reducing sugars based on the in-situ formation of core-shell gold nanorod-coated silver nanoparticles by the traditional Tollens reaction.

An effective and robust colorimetric sensor array for simultaneous detection and discrimination of five reducing sugars (i.e., glyceraldehyde (Gly), fructose (Fru), glucose (Glu), maltose (Mal), and ribose (Rib)) has been proposed. In the sensor array, two negatively charged polydielectrics (sodium polystyrenesulfonate (NaPSS) and sodium polymethacrylate (NaPMAA)), which served as the sensing elements, were individually absorbed on the surface of the cetyltrimethylammonium bromide (CTAB)-coated gold nanorods (AuNR) with positive charges through electrostatic action, forming the designed sensor units (NaPSS-AuNR and NaPMAA-AuNR). In the presence of Tollens reagent (Ag(NH3)2OH), Ag+ was absorbed on the surface of negatively charged NaPSS-AuNR and NaPMAA-AuNRs. When confronted with differential reducing sugars, different reducing sugars exhibited differential levels of deoxidizing abilities toward Ag+, thus Ag+ was reduced to diverse amounts of silver nanoparticles (AgNPs) in situ to form core-shell AuNR@AgNP by the traditional Tollens reaction method, leading to distinct colorimetric response patterns (value of AS/AL (the ratio of absorbance at 360 nm to that at 760 nm in Ag+-NaPMAA-AuNR, and the ratio of absorbance at 360 nm to that at 740 nm in Ag+-NaPSS-AuNR)). These response patterns are characteristic for each reducing sugar, and can be quantitatively distinguished by linear discriminant analysis (LDA) at concentrations as low as 10 nM with relative standard deviation (RSD) of 4.11% (n = 3). The practicability of this sensor array has been validated by recognition of reducing sugars in serum and urine samples. A colorimetric sensor array for reducing sugar discrimination based on the reduction of Ag+ and in situ formation of AuNR@AgNP.

A simple, fast and easy methodology for the monitoring of plastic migrants in alcoholic and non-alcoholic beverages using the QuEChERS method prior to gas chromatography tandem mass spectrometry.

In this work, the development of a simple, fast and reliable method for the evaluation of a group of twelve plastic migrants in alcoholic and non-alcoholic beverages widely consumed by the population has been carried out. For that, a modified QuEChERS method for the extraction and preconcentration of the target compounds has been used prior to their separation and quantification by gas chromatography coupled to triple quadrupole tandem mass spectrometry. The whole methodology was validated for beer, cider and grape juice matrices, using dibutyl phthalate-3,4,5,6-d4 as surrogate. Recovery ranged from 75 to 120% for all matrices with relative standard deviation values lower than 20%, and the limits of quantification of the method were achieved in the range 0.034-1.415 µg/L. Finally, the analysis of different beer, cider and grape juice samples commercialised in different supermarkets of Tenerife was carried out, finding the presence of four of the evaluated phthalates in the range 0.14-1.1 µg/L in some of the evaluated beers, six of them in several cider samples, in the range 0.3-2.1 µg/L, and one in the range 1.2-1.5 µg/L in three of the analysed grape juices.

In-process prepared deep eutectic solvent based homogeneous liquid-liquid microextraction for the determination of irgaphos 168 and irganox 1010 in polypropylene packed drinks.

In situ synthesis of a deep eutectic solvent and homogeneous liquid-liquid microextraction performed in a narrow bore tube was developed for efficient extraction of irgaphos 168 and irganox 1010 in doogh and water samples packed in polypropylene packages. First, pH of the aqueous sample solutions containing the analytes is adjusted at 9. Then a hydrogen bond acceptor (choline chloride) and a hydrogen bond donor (oleic acid) are dissolved in the solution and vortexed to obtain a homogeneous solution. The solution is filled into a narrow bore tube, in which its bottom was clogged by a septum. Then hydrochloric acid solution is injected into the solution by a syringe. The tube is placed in an ultrasonic bath. During this step, the droplets of choline chloride:oleic acid deep eutectic solvent are produced. The method indicated high enrichment factor (435 for irgaphos 168 and 488 for irganox 1010), low limits of detection (0.03 and 0.09 ng/mL for irgaphos 168 and irganox 1010, respectively) and quantification (0.13 and 0.29 ng/mL for irgaphos 168 and irganox 1010), good recovery (74 and 83% for irgaphos 168 and irganox 1010, respectively), and satisfactory repeatabilities (relative standard deviations ≤12%) can be obtained using the developed method.

Invited review: Astringency in whey protein beverages.

Astringency is the sensation of mouth drying and puckering, and it has also been described as a loss of lubrication in the mouth. Astringency is perceived as an increase in oral friction or roughness. Astringency caused by tannins and other polyphenols has been well documented and studied. Whey proteins are popular for their functional and nutritional quality, but they exhibit astringency, particularly under acidic conditions popular in high acid (pH 3.4) whey protein beverages. Acids cause astringency, but acidic protein beverages have higher astringency than acid alone. Whey proteins are able to interact with salivary proteins, which removes the lubricating saliva layer of the mouth. Whey proteins can also interact directly with epithelial tissue. These various mechanisms of astringency limit whey protein ingredient applications because astringency is undesirable to consumers. A better understanding of the causes of whey protein astringency will improve our ability to produce products that have high consumer liking and deliver excellent nutrition.

Contamination Levels in Recollected PET Bottles from Non-Food Applications and their Impact on the Safety of Recycled PET for Food Contact.

PET beverage bottles have been recycled and safely reprocessed into new food contact packaging applications for over two decades. During recollection of post-consumer PET beverage bottles, PET containers from non-food products are inevitably co-collected and thereby enter the PET recycling feed stream. To explore the impact of this mixing on the safety-in-use of recycled PET (rPET) bottles, we determined the concentrations of post-consumer substances in PET containers used for a range of non-food product applications taken from the market. Based on the chemical nature and amounts of these post-consumer substances, we evaluated their potential carry-over into beverages filled in rPET bottles starting from different fractions of non-food PET in the recollection systems and taking worst-case cleaning efficiencies of super-clean recycling processes into account. On the basis of the Threshold of Toxicological Concern (TTC) concept and Cramer classification tools, we present a risk assessment for potential exposure of the consumer to the identified contaminants as well as unidentified, potentially genotoxic substances in beverages. As a result, a fraction of 5% non-food PET in the recycling feed stream, which is very likely to occur in the usual recollection systems, does not pose any risk to the consumer. Our data show that fractions of up to 20%, which may sporadically be contained in certain, local recollection systems, would also not raise a safety concern.

A New Validated Potentiometric Method for Sulfite Assay in Beverages Using Cobalt(II) Phthalocyanine as a Sensory Recognition Element.

A simple potentiometric sensor is described for accurate, precise, and rapid determination of sulfite additives in beverages. The sensor is based on the use of cobalt phthalocyanine as a recognition material, dispersed in a plasticized poly(vinyl chloride) matrix membrane. o-Nitrophenyl octyl ether (o-NPOE) as a membrane solvent and tri-dodecylmethyl- ammonium chloride (TDMAC) as ion discriminators are used as membrane additives. Under the optimized conditions, sulfite ion is accurately and precisely measured under batch and flow injection modes of analysis. The sensor exhibits fast and linear response for 1.0 × 10-2-1.0 × 10-6 M (800-0.08 µg/mL) and 1.0 × 10-1-5.0 × 10-5 M (8000-4 µg/mL) sulfite with Nernstian slopes of -27.4 ± 0.3 and -23.7 ± 0.6 mV/concentration decade under static and hydrodynamic modes of operation, respectively. Results in good agreement with the standard iodometric method are obtained.Validation of the assay method is examined in details including precision, accuracy, bias, trueness, repeatability, reproducibility, and uncertainty and good performance characteristics of the method are obtained. The sensor response is stable over the pH range of 5 to 7 without any significant interference from most common anions. The advantages offered by the proposed sensor (i.e., wide range of assay, high accuracy and precision, low detection limit, reasonable selectivity, long term response stability, fast response, and long life span and absence of any sample pretreatment steps) suggest its use in the quality control/quality assurance routine tests in beverages industries, toxicological laboratories and by inspection authorities.

Effects of milk fat, casein, and serum protein concentrations on sensory properties of milk-based beverages.

Our goal was to determine the effect of systematically controlled variation in milk fat, true protein, casein, and serum protein concentrations on the sensory color, flavor and texture properties, instrumental color and viscosity, and milk fat globule size distribution of milk-based beverages. Beverage formulations were based on a complete balanced 3-factor (fat, true protein, and casein as a percentage of true protein) design with 3 fat levels (0.2, 1.0, and 2.0%), 4 true protein (TP) levels (3.00, 3.67, 4.34, and 5.00%) within each fat level, and 5 casein as a percentage of true protein (CN%TP) levels (5, 25, 50, 75, and 80%) within each protein level (for a total of 60 formulations within each of 2 replicates). Instrumental measures of Hunter L and a values and Commission Internationale de l'Éclairage (CIE) b* values, instrumental viscosity, particle size, flavor, sensory texture and sensory appearance evaluations were done on each pasteurized/homogenized beverage formulation. Within each of the 3 fat levels, higher serum protein concentration drove higher aroma intensity, sweet aromatic, cooked/sulfur, cardboard/doughy flavors, and sensory yellowness scores, whereas higher casein concentration drove higher instrumental viscosity in milk protein beverages. Increasing serum protein concentration increased yellowness, sweet aromatic, aroma intensity, cooked/sulfur, and cardboard/doughy flavors across all fat levels and also had the largest effect on L, a, and b* values, sensory whiteness, and opacity within each fat level. Increases in true protein increased throat cling and astringency intensities. Increases in fat concentration were correlated with higher L, a, and b* values, larger particle size, and increased sensory whiteness, mouth coating, cooked/milky, and milkfat flavors. Multiple linear regression of L, a, and b* values produced better predictions of sensory whiteness and yellowness of pasteurized milk protein beverages than simple linear regression of L or b* values, respectively. Formulating milk protein beverages to a higher true protein level increased astringency regardless of fat level. When formulating milk protein beverages, a product developer has a wide range of milk-based protein ingredient choices that differ in price and change price relationship across time. Understanding the expected relative effect of different milk protein ingredients on the textural and flavor characteristics of milk-based beverages could be used to help guide product reformulation decisions and ingredient choices to achieve a specific sensory profile while controlling total beverage ingredient cost.

Tongue Shape Dynamics in Swallowing Using Sagittal Ultrasound.

Ultrasound imaging is simple, repeatable, gives real-time feedback, and its dynamic soft tissue imaging may make it superior to other modalities for swallowing research. We tested this hypothesis and measured certain spatial and dynamic aspects of the swallowing to investigate its efficacy. Eleven healthy adults wearing a headset to stabilize the probe participated in the study. Both thickened and thin liquids were used, and liquid bolus volumes of 10 and 25 ml were administered to the subjects by using a cup. The tongue's surface was traced as a spline superimposed on a fan-shaped measurement space for every image from the time at which the tongue blade started moving up toward the palate at the start of swallowing to the time when the entire tongue was in contact with the palate. To measure depression depth, the distance (in mm) was measured along each radial fan line from the location at which the tongue's surface spline intersected the fan line to the point where the hard palate intersected the fan line at each timepoint. There were differences between individual participants in the imageability of the swallow, and so we defined quantitatively "measureable" and "unmeasurable" types. The most common type was measureable, in which we could find a clear bolus depression in the cupped tongue's surface. Indeed, with 10 ml of thin liquids, we were able to find and measure the depression depth for all participants. The average maximum radial distance from the palate to the tongue's surface was 20.9 mm (median) (IQR: 4.3 mm) for swallowing 10 ml of thin liquid compared to 24.6 mm (IQR: 3.3 mm) for 25 ml of thin liquid swallow (p < 0.001). We conclude that it is possible to use ultrasound imaging of the tongue to capture spatial aspects of swallowing.