Citrate selective electrodes for the flow injection analysis of soft drinks, beers and pharmaceutical products

Aiming the establishment of simple and accurate readings of citric acid (CA) in complex samples, citrate (CIT) selective electrodes with tubular configuration and polymeric membranes plus a quaternary ammonium ion exchanger were constructed. Several selective membranes were prepared for this purpose, having distinct mediator solvents (with quite different polarities) and, in some cases, p-tert-octylphenol (TOP) as additive. The latter was used regarding a possible increase in selectivity. The general working characteristics of all prepared electrodes were evaluated in a low dispersion flow injection analysis (FIA) manifold by injecting 500µl of citrate standard solutions into an ionic strength (IS) adjuster carrier (10−2 mol l−1) flowing at 3ml min−1. Good potentiometric response, with an average slope and a repeatability of 61.9mV per decade and ±0.8%, respectively, resulted from selective membranes comprising additive and bis(2-ethylhexyl)sebacate (bEHS) as mediator solvent. The same membranes conducted as well to the best selectivity characteristics, assessed by the separated solutions method and for several chemical species, such as chloride, nitrate, ascorbate, glucose, fructose and sucrose. Pharmaceutical preparations, soft drinks and beers were analyzed under conditions that enabled simultaneous pH and ionic strength adjustment (pH = 3.2; ionic strength = 10−2 mol l−1), and the attained results agreed well with the used reference method (relative error < 4%). The above experimental conditions promoted a significant increase in sensitivity of the potentiometric response, with a supra-Nernstian slope of 80.2mV per decade, and allowed the analysis of about 90 samples per hour, with a relative standard deviation <1.0%.

Development of a capillary electrophoresis method for the simultaneous analysis of artificial sweeteners, preservatives and colours in soft drinks

A rapid capillary electrophoresis method was developed simultaneously to determine artificial sweeteners, preservatives and colours used as additives in carbonated soft drinks. Resolution between all additives occurring together in soft drinks was successfully achieved within a 15-min run-time by employing the micellar electrokinetic chromatography mode with a 20 mM carbonate buffer at pH 9.5 as the aqueous phase and 62 mM sodium dodecyl sulfate as the micellar phase. By using a diode-array detector to monitor the UV-visible range (190-600 nm), the identity of sample components, suggested by migration time, could be confirmed by spectral matching relative to standards.

Caffeine as a flavor additive in soft-drinks

Over 60% of soft-drinks sold in the United States contain caffeine, a mildly addictive psycho-active chemical, as a flavor additive. Using sweeteners as controls, we assessed whether caffeine has flavor activity in a cola soft-drink. A forced-choice triangle discrimination methodology was used to determine detection thresholds of caffeine in sweeteners and a cola beverage. The subjects (n=30, 28 female, 23±4 years old) were trained tasters and completed over 1600 discrimination tests during the study. The mean detection thresholds for caffeine in the sweet solutions were: 0.333±0.1 mM sucrose; 0.467±0.29 mM aspartame; 0.462±0.3 mM sucralose, well below the concentration in common cola beverages (0.55–0.67 mM). A fixed concentration of caffeine, corresponding to the concentration of caffeine in a common cola beverage (0.67 mM) was added to the sweeteners and a non-caffeinated cola beverage. Subjects could distinguish between caffeinated and non-caffeinated sweeteners (p<0.001), but all subjects failed to distinguish between caffeinated and non-caffeinated cola beverage (p=1.0). Caffeine has no flavor activity in soft-drinks yet will induce a physiologic and psychologic desire to consume the drink.

The 'caffeine-sweetness' effect; potential reduction of energy in caffeinated sugar-sweetened soft drinks

Background – Excessive consumption of sugar sweetened beverages (SSB) is a contributing factor in the occurrence of overweight and obesity. The high energy intake, low satiation, high glycemic index, and intense marketing are all thought to contribute to their over consumption. In addition, the role of the mildly-addictive chemical caffeine in SSB has been questioned (Griffiths and Vernotica, 2000, Keast and Riddell, 2007). We have previously shown that low concentrations of caffeine may decrease sweetness of sugars and thereby result in excess energy in SSB formulations (Ebbeling et al., 2006).
Objective – Without noticeably affecting flavour, to determine potential energy reduction when decreasing sucrose concentration from caffeinated and de-caffeinated SSB.
Design – Human psychophysical taste evaluations in water, sucrose and model SSB. Triangle forced-choice ascending method of limits was used to determine caffeine taste threshold in water and sucrose (n= 62). Directional paired comparison tests to determine 1/ the influence of caffeine on sweetness of sucrose (n= 23), and 2/ the nonperceivable difference when decreasing the sucrose and caffeine concentrations in a model SSB (n= 30).
Outcomes – Caffeine, at sub-threshold concentrations in common SSB (0.67mM) can be perceived in sucrose solutions because it significantly inhibits sweetness (p<0.001), the ‘caffeine sweetness effect’. Presumably coremoval of caffeine and sucrose could be achieved without affecting the sweetness of the SSB. Removing caffeine from the model SSB allowed an energy reduction of 137.4 KJ per 500 ml serving (12.6% sucrose reduction) without noticeably affecting flavour for 80% of the population. The energy reduction possible without co-removal of caffeine was a more modest 32 KJ per 500 ml serving (3.5% sucrose reduction).
Conclusion – Sub-threshold concentrations of caffeine suppress sweetness resulting in higher concentrations of sugars in SSB. Excessive consumption of SSB is linked to the obesity epidemic, and we suggest the removal of caffeine and subsequent removal of 137.4 KJ energy will have long term public health benefits.

Influences on consumption of soft drinks and fast foods in adolescents

Soft drink and fast food are energy dense foodstuffs that are heavily marketed to adolescents, and are likely to be important in terms of risk of obesity. This study sought to examine the influences on soft drink and fast food consumption among adolescents as part of a cross-sectional survey of 2,719 adolescents (aged 11-16) from 93 randomly selected schools in New South Wales, Australia. Students provided information on soft drink and fast food consumption, and responded to statements examining influences over consumption. Over half of the boys and more than one third of the girls reported drinking soft drink daily, and consumption peaked in Grade 8 students. A quarter of students reported choosing soft drinks instead of water or milk, and around 40% agreed that soft drink was usually available in their homes. Availability in the home and drinking soft drinks with meals was most strongly associated with consumption in all age groups. Fast food consumption was higher among boys than girls in all age groups. Convenience and value for money yielded the strongest associations with fast food
consumption in boys, while preferring fast food to meals at home and preferring to “upsize” meals were most strongly associated with consumption in girls. Interventions to reduce consumption of soft drinks should target availability in both the home and school environment by removing soft drinks and replacing them with more nutritive beverages. Fast food outlets should be encouraged to provide a greater range of healthy and competitively priced options in reasonable portions.

Openability of soft drinks PET packagings

Studies on packaging accessibility are still incipient in Brazil. Many of these packagings can represent a challenge to users, whether due to non-informative labels, tricky tabs or seals, or even those that need strength to open. This paper brings a simple test to determine the necessary torque force to open PET bottles, and to predict the amount of users that could not open it. The findings suggest that a considerable amount of users could not open it or would have some difficulties to exert the necessary force.

Development of a potentiometric sensor for the determination of saccharin in instant tea powders, diet soft drinks and strawberry dietetic jam

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Electrothermal AAS determination of Ni in soft drinks using Co as the internal standard

A method for the direct determination of Ni in soft drinks by graphite furnace atomic absorption spectrometry using a transversely heated graphite atomizer (THGA), Zeeman-effect background corrector, and Co as the internal standard (IS) is proposed. Magnesium nitrate was used to stabilize both Ni and Co. All diluted samples (1+1) in 0.2% (v/v) HNO3 and reference solutions [5.0-50 mu g L-1 Ni in 0.2% (v/v) HNO3] were spiked with 50 mu g L-1 Co. For a 20-mu L sample dispensed into the atomizer, correlations between the ratio of absorbance of Ni to absorbance of Co and the analyte concentration were close to 0.9996. The relative standard deviation of the measurements varied from 0.5 to 3.4% and 1.0 to 7.0% (n=12) with and without IS, respectively. Recoveries within 98-104% for Ni spikes were obtained using IS. The characteristic mass was calculated as 43 pg Ni and the limit of detection was 1.4 mu g L-1. The accuracy of the method was checked for the direct determination of Ni in soft drinks and the results obtained with IS were better than those without IS.

Chronic consumption of fructose rich soft drinks alters tissue lipids of rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Heuristics and meta-heuristics for lot sizing and scheduling in the soft drinks industry: A comparison study

This chapter studies a two-level production planning problem where, on each level, a lot sizing and scheduling problem with parallel machines, capacity constraints and sequence-dependent setup costs and times must be solved. The problem can be found in soft drink companies where the production process involves two interdependent levels with decisions concerning raw material storage and soft drink bottling. Models and solution approaches proposed so far are surveyed and conceptually compared. Two different approaches have been selected to perform a series of computational comparisons: an evolutionary technique comprising a genetic algorithm and its memetic version, and a decomposition and relaxation approach. © 2008 Springer-Verlag Berlin Heidelberg.

Supplementation of soft drinks with metallic ions reduces dissolution of bovine enamel

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Bone mineral density evaluation in rats submitted to daily diet of coffee and soft drinks

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)