Gillian Eggleston

Recently, like previously for fat and protein, there has been negative discussion about carbohydrate, including blaming it for the rise of obesity and related metabolic conditions, even though overconsumption and sedentary lifestyles are more defined contributors. In many parts of the world, natural sugar (sucrose) from sugarcane is the main dietary source of carbohydrate. Considerable misinformation about sugar is in the public domain with the average consumer being unaware of (i) the critical need of body cells, particularly brain cells, for sugar to function, (ii) the multitude of functionalities other than sweetening that sugar imparts, and (iii) micronutrients delivered with many sugar products.

The sporadic appearance of floc from refined, white cane sugars in alcohol beverages remains a technical problem for both beverage manufacturers and sugar refiners. Cane invert sugars mixed with 60% pure alcohol and water increased light scattering by up to ∼1000-fold. Insoluble and soluble starch, fat, inorganic ash, oligosaccharides, Brix, and pH were not involved in the prevailing floc-formation mechanism. Strong polynomial correlations existed between the haze floc and indicator values (IVs) (color at 420 nm pH 9.0/color at pH 4.0-an indirect measure of polyphenolic and flavonoid colorants) (R2 = 0.815) and protein (R2 = 0.819) content of the invert sugars. Ethanol-induced denaturation of the protein exposed hydrophobic polyphenol-binding sites that were further exposed when heated to 80 °C. A tentative mechanism for floc formation was advanced by molecular probing with a haze (floc) active protein and polyphenol as well as polar, nonpolar, and ionic solvents.

Some commercial sweet sorghum syrups can be fraudulently or accidently adulterated with inexpensive sugar syrups, particularly high fructose corn syrup (HFCS) or corn syrup, and sold at a relatively low market price or even mis-branded. This undermines the economic stability of the current small-scale producers of food-grade sweet sorghum syrup as well as the developing large-scale bioproduct industry. An analytical method is urgently needed to evaluate adulterated commercial sweet sorghum syrups. Ion chromatography with integrated pulsed amperometric detection (IC-IPAD) has been previously used to differentiate white, refined sugars manufactured from sugarcane and sugar beet. By applying a strong IC-IPAD NaOH/NaOAc gradient method over 45 min, monosaccharides, oligosaccharides and oligosaccharide isomers of at least 2 to 12 dp, as well as sugar alcohols can be detected in multiple commercial sweet sorghum and other sugar syrups. Fingerprint IC oligosaccharide profiles are extremely selective, sensitive, and reliable. By using five characteristic marker chromatography peaks of high fructose corn syrup (HFCS), including isomaltose, maltose and maltotriose, in combination with a low sucrose peak, adulterated and mis-branded syrups were identified. The analysis of 7.0 Brix blind syrup samples, marker peaks allowed the detection of as low as 10% HFCS adulteration, which is within the lower limit of adulteration before action is taken.