Amalia Mirta Calviño

Interactions between Co2 Oral Pungency and Taste

Two experiments are reported in which the perceptual interactions between oral pungency, evoked by CO2, and the taste of each of four tastants–sucrose (sweet), quinine sulfate (bitter), sodium chloride (salty), and tartaric acid (sour)–were explored. In experiment 1 the effect of three concentrations of each tastant on the stimulus-response function for perceived oral pungency, in terms of both rate of change (slope) and relative position along the perceived pungency axis, was determined. In experiment 2 the effect of three concentrations of CO2 on the stimulus-response function for the perceived taste intensity of each tastant was examined. Results show that the characteristics of the mutual effects of tastant and pungent stimulus depend on the particular tastant employed. Sucrose sweetness and CO2 oral pungency have no mutual effect; sodium chloride saltiness or tartaric acid sourness and CO2 oral pungency show mutual enhancement; and quinine sulfate bitterness abates CO2 oral pungency, whereas CO2 has a double and opposite effect on quinine sulfate bitterness–at low concentrations of bitter tastant CO2 enhances bitterness, and at high concentrations of bitter tastant CO2 abates bitterness. It is suggested that the perceptual attributes of saltiness and sourness are closer, from a qualitative point of view, to oral pungency than are the attributes of bitterness and sweetness.

Perception of sweetness and bitterness in different vehicles

In the present study, we investigated taste-taste, taste-vehicle, and simultaneous taste-vehicle-taste mixtures. Subjects made estimates of the sweetness and bitterness of 27 stimuli. Sucrose (292, 585, and 1170 mM), caffeine (13, 26, and 52 mM), and binary mixtures of low (292-13 mM), middle (585-26 mM), and high (1170-52 mM) levels of both components were dispersed in water, carboxymethylcellulose (CMC) 1% w/v, and gelatin 6% w/v. The sweetness and bitterness of the sucrose-vehicle-caffeine combinations were significantly weaker than the respective sucrose-vehicle and caffeine-vehicle combinations. The emerged mutual suppressive effects were asymmetrical and persisted when both tastants were presented in CMC and gelatin. Moreover, the increase in vehicle consistency and the simultaneous addition of another taste reduced the perceived intensity of a taste either presented alone or dissolved in water. For both sweetness and bitterness, the total taste suppression observed was always significant.

Bibliometric study on food science and technology: Scientific production in Iberian-American countries (1991-2000)

This study presents a bibliometric analysis of the scientific production in the food science and technology (FST) field for the period 1991-2000, in Iberian-America (IA). Eight selected IA countries contributed 97.6% of the IA production and accounted for a 6.6% of the world production. The most frequent document type is journal article published in English. Retrieved records display characteristical authorship patterns and preferred subject areas. Spain, Brazil, Mexico, Argentina and Portugal determine the IA pattern of sources of publication. The fifty top ranked journals, 80% of which were indexed by the SCIE, encompass two-thirds of the IA production.

Assessment of research performance in food science and technology: Publication behavior of five Iberian-American countries (1992-2003)

SummaryThis study is a follow-up to a published descriptive outline on the publications of Iberian-American (IA) countries in food science and technology field. The number of articles and citations attained by IA producers (Argentina, Brazil, Mexico, Portugal and Spain) were examined on 48 journals indexed in Science Citation Index (SCI) database. The growth rate in publication between 1992 and 2003 depicted differences across journals, those with high impact factor were most preferred by IA authors. Different patterns of collaboration and frequency of citations were obtained. Spain and Argentina show the greatest counts of publications and citations but present the lowest percentages of collaboration with outside authors. Instead, three out of ten papers from Portugal, Mexico and Brazil are signed by at least one foreign author. The association of publication productivity to demographic and socio-economic indicators revealed that Spain and Portugal have the highest ratios of publications or citations by human resources followed by Argentina. Argentina showed the highest ratios of publications or citations by expenditure on science and technology activities.

Note. Caffeine Content and Dynamical Bitterness of Yerba Mate Ilex paraguariensis Infusions

The infusion of yerba mate (YM) Ilex paraguariensis, with its typical bitterness, is traditionally consumed in South America as a mild stimulant beverage. Two types of YM, with sticks (YM-S) and without sticks (YM-L) and three brands for each type were evaluated for caffeine content and the time course of bitterness. The chemical analysis of the six YM infusions at 5% w/v made by high performance liquid chromatography (HPLC) showed that caffeine levels were higher for YM-L brands. The kinetic study of YM bitterness assessed by time-intensity (TI) curves revealed that the presence of sticks lowered maximum intensity, total duration and area under the curve of bitter perception.

Chemometrics Classification of Argentine Clover and Eucalyptus Honeys According to Palynological, Physicochemical, and Sensory Properties

Palynological, physicochemical, and sensory methods were applied to ascertain the most discriminant variables for honey characterization. Fifteen physicochemical parameters, six indicators of antioxidant capacity and eight sensory attributes were considered. Clover and eucalyptus honeys were differentiated when the linear discriminant analysis was applied. Electrical conductivity, sugars, ferric ion reducing, and Trolox equivalent antioxidant capacity were the most discriminant variables. Odor and color intensities were the sensory attributes scoring the major differences between honeys. The canonical correlations technique pointed out that differences were related primarily to the content of pollen from Trifolium, Medicago sativa, and Lotus. These standards of quality provide a differentiating tool to classify unifloral honeys.

Psychophysical Assessments of Sourness in Citric Acid-Ethanol Mixtures

The effect of ethanol in modulating the intensity and duration of the perceived sourness induced by citric acid was studied. Magnitude Estimation-Converging Limits method was applied to rate the sourness of seven solutions (3–70 mM) of citric acid in aqueous solution presented alone and mixed with 8% V/V or 15% V/V ethanol. Dynamic sourness ratings of 5, 15, and 45 mM citric acid alone and mixed with the same two ethanol levels were assessed by the Time Intensity Method (TI). Results were consistent with both methods. Sourness changed with citric acid concentration and ethanol levels. From TI measurements, a similar interactive pattern was obtained for parameters as duration, area under the curve, peak and average intensity.

Is sensory-specific satiety for a bitter-sweet infusion modulated by context?

The sensory-affective attributes of beverages have an important influence on a given intake and successive consumptions because of sensory-specific satiety (SSS; defined as a decrease in pleasantness ratings of a food eaten relative to uneaten foods). No studies have, however, investigated how multiple sessions of SSS for familiar drinks over a period of several days up to a week may change their pleasantness and how these hedonic-related judgments are affected by the context during SSS testing. With twenty-six participants, the present study explored the medium lasting and contextual effects of repeated SSS sessions for a bitter-sweet infusion on olfactory and flavour pleasantness over the course of three exposures in either a laboratory or a cafeteria setting. The results showed olfactory and flavour SSS for the infusion following each consumption in both the artificial and the natural setting. More interestingly, despite the failure to detect medium-term SSS (i.e., a greater decrease in pleasantness ratings of a food eaten relative to uneaten foods after repeated SSS sessions over several days as compared to the first SSS session), a contextual modulation of olfactory SSS was observed with a lesser overall magnitude in the cafeteria compared to the laboratory setting. To the best of our knowledge, the impact of eating location on the development of satiation and the differential contextual sensitivity of SSS for orthonasal odours and flavours has not been reported previously. The implications of potential environmental control of SSS are considered in this study.

Regional tongue sensitivity for sweetness and pungency of ethanol-aspartame mixtures.

Binary mixtures of aspartame prepared at three levels of concentration and dissolved in four ethanolic dilutions were perceptually evaluated. Sweet-pungent combinations were presented in solution or in disks of filter paper (paper) soaked in the solutions. Variations in sweetness and pungency were examined at two oral loci including the tip and the back plus the front of the tongue in the liquid condition or the tip and the back of the tongue in the paper condition. A similar behavior was observed in liquid and paper conditions; as the concentration of aspartame and ethanol increased so did the intensity for sweet and pungent qualities. Whereas sweetness was not influenced by ethanol addition (2-8 % V/V), a suppressive effect of aspartame (1-4 mM) on pungency was noted for liquid but not for the paper condition. Sweetness was enhanced when the back plus the front of the tongue was stimulated by solutions. Finally, there was a complex pattern of regional effects on the perceived pungency of alcoholic-sweet solutions that was not replicated in the paper condition.