Sucrose
Properties
| State | Solid (white crystalline) |
| Color | White |
| Solubility | Highly soluble in water (2,000 g/L at 25°C); slightly soluble in ethanol; insoluble in nonpolar solvents |
| Melting Point | 186°C (decomposes; caramelizes) |
| Boiling Point | Decomposes before boiling |
About Sucrose
Sucrose is the disaccharide α-D-glucopyranosyl-(1→2)-β-D-fructofuranoside (342.296 g/mol), the molecule that the world simply calls sugar. Two anomeric carbons — C1 of glucose and C2 of fructose — are locked head-to-head by a glycosidic bond, which is what makes sucrose a non-reducing sugar (no free hemiacetal can open to expose an aldehyde, so Benedict's, Fehling's, and Tollens' reagents all give negative results). Cleave that bond with the enzyme invertase or with dilute acid and you get an equimolar mix of glucose and fructose called invert sugar; the optical rotation flips from +66.5° (sucrose) to about −20° (the mixture, dominated by levorotatory fructose), which is why the reaction is called inversion and why it was the system Wilhelmy used in 1850 to write down the first quantitative rate law in chemistry. Plants synthesize sucrose in the cytosol of leaf mesophyll cells from UDP-glucose and fructose-6-phosphate via sucrose-phosphate synthase, then load it into the phloem for long-distance transport to roots, fruits, and developing seeds. Industrial extraction from sugarcane (Saccharum officinarum, ~14% sucrose by stem mass) and sugar beets (Beta vulgaris, ~17% by root mass) yields about 180 million tonnes of refined sucrose globally per year, making it one of the largest tonnage purified organic chemicals on the planet.
Where you'll encounter it
If you've ever made caramel by heating sugar in a dry pan and watched it pass through transparent gold, amber, then dark mahogany before turning bitter and black, you're watching sucrose first melt around 186°C, then thermally invert to glucose and fructose, then undergo a cascade of dehydration, condensation, and Maillard-like reactions producing furans, hydroxymethylfurfural (HMF), and brown polymeric melanoidins. In a brewery or distillery, sucrose is the substrate for Saccharomyces cerevisiae invertase, which cleaves it before glycolysis; rum, cachaça, and aguardiente are all made by fermenting and distilling cane-derived sugar streams. In a chromatography lab, sucrose density gradients (typically 5–60% w/v in 5% steps) are the classical method for separating ribosomal subunits, polysomes, and viral particles by ultracentrifugation. And on the cleaning side, sucrose esters of stearic and palmitic acids (Sucroglycerides, E473) are non-ionic surfactants used in baking and cosmetics where the polyol backbone gives biodegradability that polyethoxylates can't match.
Common Uses
- Sweetener in food, beverages, baking, and confectionery (about 180 Mt/year globally)
- Substrate for Saccharomyces cerevisiae fermentation in beer, wine, rum, and ethanol production
- Bulking agent and crystallization-control medium in jams, jellies, and fondant fillings
- Sucrose density gradient medium for ultracentrifugation of ribosomes and viral particles
- Cryoprotectant excipient in lyophilized vaccine and protein formulations
- Reducing-sugar precursor (via invertase hydrolysis) for high-fructose corn syrup analogs
- Carbon source in industrial fermentations producing citric acid, lactic acid, and lysine
Safety Information
GRAS under 21 CFR 184.1854 with no upper limit. No OSHA PEL or ACGIH TLV. Long-term overconsumption is causally linked to dental caries (Streptococcus mutans uses sucrose preferentially to build biofilms), insulin resistance, NAFLD, and obesity-related morbidity — WHO recommends free sugars below 10% of total energy intake and ideally below 5%. The industrial dust hazard is real: powdered sugar has a minimum explosible concentration around 35 g/m³ and the Imperial Sugar refinery explosion in Port Wentworth, Georgia in 2008 killed 14 workers when a fugitive dust cloud ignited inside a packaging building. Sugar refineries handle this through enclosed conveyors, dust collection at all transfer points, and routine housekeeping under NFPA 654 combustible dust standards.
This safety summary is for educational reference only and may not be complete. It is not a substitute for Safety Data Sheets (SDS), medical advice, or professional chemical safety guidance. Always consult appropriate SDS and qualified professionals before handling chemicals.