Den arena där socker och sötma förstärs har förändrats i och med att socker har gått från en global handelsvara, endast tillgänglig ett fåtal, till en lokal som når de stora massorna. Detta kanske kan ses som en mindre revolution i mathållningen. Men varför äter människan socker och varför finner hon smaken så åtråvärd? Syftet med studien var att ur ett evolutionärt samt kulturellt perspektiv undersöka varför människan finner den söta smaken åtråvärd. Metoden som har använts i föreliggande studie var en litteraturstudie av vetenskapliga artiklar där artiklar som berör hälsoaspekter som socker och sötma orsakar diskuteras emot bakgrundens evolutionära samt kulturella aspekter. Resultatet visade att människan fann den söta smaken åtråvärd baserat både på medfödda samt kulturellt inlärda preferenser. Av diskussionen framgick att det fanns en medfödd preferens för sötma men att den kulturellt betingade preferensen tog över genom den inlärning hon får från sin första måltid av modersmjölk och framåt. Människan förknippade därför sött med både trygghet, lugn, belöning, tröst men framförallt med mat. För om sötma endast vore evolutionärt betingat skulle människan kunna äta socker direkt ur påsen. / B-uppsatser

Comparative studies of taste perception have found that primates may differ markedly in their sensitivity for substances perceived as sweet by humans. These findings raise questions about the reason that may underlie these differences in sweet-taste sensitivity between species. The aim of the present study was to assess the taste responsiveness of chimpanzees (Pan troglodytes verus) to seven substances tasting sweet to humans and to compare the results with those of other primate species. Using a two-bottle preference test (1 min) I found that the taste preference thresholds of the chimpanzees for five food-associated carbohydrates ranged between 20-30 mM for sucrose, 20-50 mM for fructose, 60-80 mM for glucose, 50-80 mM for maltose, and 30-80 mM for lactose. Taste preference thresholds for two steviol glycosides ranged from 0.04-0.05 mM for stevioside, and 0.03-0.05 mM for rebaudioside A. The chimpanzees displayed clear preferences for all sweet-tasting substances presented. In line with data obtained in other primates, the taste preference threshold of the chimpanzees for sucrose was lower compared to the other carbohydrates presented and the taste preference thresholds for stevioside and rebaudioside A were lower compared to sucrose. In general, the taste sensitivity of the chimpanzees fell into the range of data reported in other nonhuman primate species. Interestingly, the taste preference thresholds of the chimpanzees reported here are similar to the taste detection thresholds obtained in humans, despite the fact that the former are only a conservative approximation of an animal’s taste sensitivity. This suggests that chimpanzees may be as sweet-taste sensitive as humans.

Studies on taste perception in nonhuman primates contribute to the understanding of the evolution of the sense of taste. To assess the responsiveness of four adult spider monkeys (Ateles geoffroyi) to a set of substances perceived as sweet by humans, two-bottle preference tests were performed to determine taste preference thresholds, and taste-induced facial responses were analyzed. The spider monkeys displayed a significant preference for concentrations as low as 0.2-1 mM acesulfame K, 0.002-0.5 mM alitame, 10-20 mM isomalt, 0.002-0.5 mM sodium saccharin, 2-20 mM galactose and 20-50 mM sorbitol over water. The spider monkeys were generally unable to perceive aspartame and, based on their facial responses, probably do not perceive it as sweet. Thaumatin and monellin were not detected, and most likely neither was the sweetness of sodium cyclamate. Sodium saccharine and sodium cyclamate were rejected at high concentrations by at least one monkey, which is congruent with the perception of a bitter side taste as reported in humans. A significant correlation was found between the ranking order of sweetening potency for the different substances of spider monkeys and humans, but not between spider monkeys and chimpanzees. The results suggest that spider monkeys may be generally more sensitive than chimpanzees and at least as sensitive as humans to the tested substances, supporting the notion that high sensitivity to sweet taste may be associated with a frugivorous dietary specialization. The lack of responsiveness to some of the substances supports the notion of a dichotomy in sweet-taste perception between platyrrhine and catarrhine primates.

Differences in taste perception between species are thought to reflect evolutionaryadaptations to dietary specializations such as seed predation. By employing a two-bottlepreference test, the purpose of the current study was to evaluate the taste responsiveness forfive food-associated carbohydrates and two steviol glycosides in four adult white-faced sakis(Pithecia pithecia). The taste preference thresholds were found to be 10 mM for sucrose, 10-40 mM for fructose, 20-30 mM for glucose and maltose, and 30-40 mM for lactose. The sakisalso showed a clear preference for rebaudioside A and stevioside over tap water atconcentrations as low as 0.04 and 0.2-0.5 mM, respectively. When given the choice betweenall binary combinations of the five carbohydrates at equimolar concentrations of 100, 200,and 300 mM, respectively, the sakis displayed the following preference pattern: sucrose >fructose > glucose ≥ maltose = lactose. The obtained taste preference thresholds for foodassociated carbohydrates fall into the lower range of values among primates, suggesting acomparatively high sweet-taste sensitivity in the sakis. The pattern of relative preferenceswas consistent with that reported in most tested primates. Altogether, the responsivenesstowards the sweet-tasting substances obtained in this seed predator resembles the resultsobtained in primates which act as seed dispersers. However, these results might reflect anevolutionary adaptation of white-faced sakis to exploit resources containing low sugarconcentrations such as unripe fruits and seeds.