**1. Sweet Substances:**
– Sucrose, fructose, and amino acids like alanine, glycine, and serine are sweet.
– Plant glycosides like glycyrrhizin and stevioside are sweeter than sucrose.
– Sweet proteins like thaumatin and hen egg lysozyme are potent natural sweeteners.
– Various compounds like lactose, maltose, and sorbitol have different sweetness levels.
– Some inorganic compounds like beryllium chloride and lead(II) acetate are sweet.
**2. Sweetness Modifiers:**
– Lactisole inhibits sweet tastes and is used in jellies to enhance fruit flavors.
– Gymnemic acid and ziziphin inhibit sweetness perception and are used in herbal medicine.
– Miraculin and curculin make sour foods taste sweet temporarily.
– Some substances like lactisole suppress the perception of sweetness.
– Others like gymnemic acid and ziziphin inhibit the perception of sweet tastes.
**3. Sweetness Receptor and Evolution:**
– Sweetness is perceived by taste buds on the tongue.
– The preference for sweetness has ancient evolutionary origins.
– Bitterness tends to indicate toxicity in food sources.
– Primate ancestors sought sweet-tasting and energy-dense foods.
– Human physiology retains ancient preferences for sweet tastes.
**4. Sweetness Perception Studies:**
– Sweetness detection threshold is around 1 part in 200 of sucrose in solution.
– Bitterness has a lower detection threshold compared to sweetness.
– Studies show responsiveness to sweetness has ancient evolutionary roots.
– Newborn infants show preferences for high sugar concentrations.
– Sweetness recognition varies between individuals and species.
**5. Sweetness in Health and Nutrition:**
– Excessive sugar consumption linked to obesity and diabetes.
– Artificial sweeteners may have controversial health effects.
– Natural sweeteners provide some nutritional benefits.
– Sugar substitutes used in diabetic diets.
– Moderation in sweetener consumption recommended for overall health.
This article needs additional citations for verification. (April 2024) |
Sweetness is a basic taste most commonly perceived when eating foods rich in sugars. Sweet tastes are generally regarded as pleasurable. In addition to sugars like sucrose, many other chemical compounds are sweet, including aldehydes, ketones, and sugar alcohols. Some are sweet at very low concentrations, allowing their use as non-caloric sugar substitutes. Such non-sugar sweeteners include saccharin, aspartame, and sucralose. Other compounds, such as miraculin, may alter perception of sweetness itself.
The perceived intensity of sugars and high-potency sweeteners, such as aspartame and neohesperidin dihydrochalcone, are heritable, with gene effect accounting for approximately 30% of the variation.
The chemosensory basis for detecting sweetness, which varies between both individuals and species, has only begun to be understood since the late 20th century. One theoretical model of sweetness is the multipoint attachment theory, which involves multiple binding sites between a sweetness receptor and a sweet substance.
Studies indicate that responsiveness to sugars and sweetness has very ancient evolutionary beginnings, being manifest as chemotaxis even in motile bacteria such as E. coli. Newborn human infants also demonstrate preferences for high sugar concentrations and prefer solutions that are sweeter than lactose, the sugar found in breast milk. Sweetness appears to have the highest taste recognition threshold, being detectable at around 1 part in 200 of sucrose in solution. By comparison, bitterness appears to have the lowest detection threshold, at about 1 part in 2 million for quinine in solution. In the natural settings that human primate ancestors evolved in, sweetness intensity should indicate energy density, while bitterness tends to indicate toxicity. The high sweetness detection threshold and low bitterness detection threshold would have predisposed our primate ancestors to seek out sweet-tasting (and energy-dense) foods and avoid bitter-tasting foods. Even amongst leaf-eating primates, there is a tendency to prefer immature leaves, which tend to be higher in protein and lower in fibre and poisons than mature leaves. The "sweet tooth" thus has an ancient heritage, and while food processing has changed consumption patterns, human physiology remains largely unchanged.