Bitter and sweet components of ethanol taste in humans
Introduction
It has been repeatedly reported that rodents with a high preference for sweet substances (e.g. saccharin or sucrose) consume more ethanol (alcohol) than rats or mice with a low preference for these substances (Gosnell and Krahn, 1992, Bachmanov et al., 1996; for review, see Kampov-Polevoy et al., 1999). The above correlation has been reported for both genetically selected alcohol preferring (Sinclair et al., 1992, Stewart et al., 1994, Kampov-Polevoy et al., 1996) and outbred strains of rats (Gosnell and Krahn, 1992, Koros et al., 1998, Kampov-Polevoy et al., 1999). The interaction between the intake of sweet substances and the preference for ethanol seems not to be limited to rodents. An increased ethanol intake among adolescents was correlated with an increased intake of sugars and sweets (Yamamoto et al., 1991). More recently, Kampov-Polevoy et al. (1997) have found that compared to controls, more alcoholic subjects preferred high sucrose concentrations.
At least two hypothesis could explain the mechanism of association between sweets consumption and alcohol drinking. First, one could speculate that a common neurochemical substrate in the CNS mediates rewarding properties of sweets and ethanol (Kampov-Polevoy et al., 1999). For example, there is a growing body of evidence linking excessive consumption of sweets and alcohol to the brain opioid system (Lynch, 1986, Gosnell and Majchrzak, 1989, Herz, 1997, Bienkowski et al., 1999).
The second hypothesis deals with peripheral taste factors. Ethanol-associated taste cues have been repeatedly proposed to determine ethanol drinking behaviour especially in alcohol-naive individuals (Richter, 1941, Fromme and Samson, 1983, Di Lorenzo et al., 1986). In line with the above suggestions, Samson et al. (1989) have shown that first exposure to ethanol taste is aversive in more than 40% of men and women and that this aversive response tends to predict future abstinence. Electrophysiological and behavioural studies in non-human subjects have suggested that ethanol taste has both bitter and sweet components (Di Lorenzo et al., 1986, Kiefer and Lawrence, 1988, Hellekant et al., 1997). Also preliminary experiments with human subjects have revealed that low ethanol concentrations may produce some sweet sensations (Wilson et al., 1973). Given the above, one could assume that the relationship between sweets preference and ethanol intake results, at least partially, from similar taste responses to sweets and alcohol (for recent discussion, see Bachmanov et al., 1996).
The purpose of the present study was twofold. First, we aimed to examine descriptive responses to ethanol taste in healthy human volunteers. For this reason two experiments were done. In experiment 1, participants described taste sensations produced by different concentrations of ethanol. In experiment 2, the subjects assessed similarity of tastant mixtures to ethanol.
The second aim of the present study was to search for correlations between responses to sucrose and ethanol taste. Thus, in experiment 1 reactivity to sucrose taste was also analysed.
Section snippets
Subjects
Twenty healthy volunteers (eight males, 12 nonpregnant females) participated in the study. All subjects consumed at least one standard drink per week and were classified as social drinkers. Eight participants were also regular cigarette smokers. Their mean (±S.D.) Fagerström Tolerance Questionnaire (Fagerström, 1978) score was 3.5 (±1.2). Table 1 presents basic characteristics of the participants including parameters of cigarette consumption in the smoking group.
Candidates for the study were
Intensity and pleasantness of sucrose and ethanol taste — effects of gender and smoking status
The ANOVA did not reveal any effect of gender or smoking status on responses to either ethanol or sucrose solutions (all Fs<1, Ps>0.2; data not shown).
Fig. 1 presents mean intensity (A,B) and pleasantness (C,D) of the taste of different sucrose and ethanol concentrations. In addition, number of subjects assigning highest pleasantness score to a given concentration is shown in parentheses.
Subjective evaluation of ethanol taste
All subjects identified bitter sensations in the taste of ethanol samples. For example, 10% ethanol, i.e.
Discussion
In agreement with previous reports (Weizenbaum et al., 1980, Hyde and Feller, 1981, Kunka et al., 1981; but see also Conner and Booth, 1988), there were no major differences in responses to sweet taste between males and females in the present study. Similarly, we did not find any differences in sweet taste reactivity between smokers and non-smokers. Several investigators have shown that smoking status does not alter sweet taste intensity (Peterson et al., 1968, Redington, 1984, Perkins et al.,
Acknowledgements
This study was supported by PARPA (grant Alc 18/99) and the State Committee for Scientific Research (KBN grant no. 4 PO5A 083 17).
References (37)
- et al.
Ethanol-reinforced behaviour in the rat: effects of naltrexone
Eur. J. Pharmacol.
(1999) - et al.
Preferred sweetness of a lime drink and preference for sweet over non-sweet foods, related to sex and reported age and body weight
Appetite
(1988) - et al.
Disorders of smell and taste
Med. Clin. N. Am.
(1999) - et al.
Neural and behavioral responsivity to ethyl alcohol as a tastant
Alcohol
(1986) Measuring degree of physical dependence to tobacco smoking with reference to individualization of treatment
Addict. Behav.
(1978)- et al.
Centrally administered opioid peptides stimulate saccharin intake in nondeprived rats
Pharmacol. Biochem. Behav.
(1989) - et al.
The taste of ethanol in a primate model: I. Chorda tympani nerve response in Macaca mulatta
Alcohol
(1997) - et al.
Age and sex effects on taste of sucrose, NaCl, citric acid and caffeine
Neurobiol. Aging
(1981) - et al.
Pain sensitivity and saccharin intake in alcohol-preferring and alcohol-nonpreferring rat strains
Physiol. Behav.
(1996) Opioid blockade inhibits saccharin intake and blocks normal preference acquisition
Pharmacol. Biochem. Behav.
(1986)
Perception and hedonics of sweet and fat taste in smokers and nonsmokers following nicotine intake
Pharmacol. Biochem. Behav.
Sweet taste preference in women smokers: comparison with nonsmokers and effects of menstrual phase and nicotine abstinence
Pharmacol. Biochem. Behav.
Taste differences between cigarette smokers and nonsmokers
Pharmacol. Biochem. Behav.
Weight change following smoking cessation: the role of food intake and exercise
Addict. Behav.
Taste preferences in rat lines selected for high and low ethanol consumption
Alcohol
Relationship among reproductive variables, sucrose taste reactivity and feeding behavior in humans
Physiol. Behav.
Intake of ethanol, sodium chloride, sucrose, citric acid, and quinine hydrochloride solutions by mice: a genetic analysis
Behav. Genet.
The prevalence and risk factors associated with abusive or hazardous alcohol consumption in 16-year-olds
Addiction
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