Maltohexaose

Characterisation of brewpub beer carbohydrates using high performance anion exchange chromatography coupled with pulsed amperometric detection.[Pubmed: 24001825 ]

Food Chem. 2014 Jan 1;142:152-8.

High performance anion exchange chromatography (HPAEC) coupled with pulsed amperometric detection (PAD) was optimised in order to quantify mannose, maltose, maltotriose, maltotetraose, maltopentaose, Maltohexaose and maltoheptaose content of beer.
METHODS AND RESULTS:
The method allows the determination of above mentioned oligosaccharides, in a single chromatographic run, without any pre-treatment. Limit of detection and limit of quantification were suitable for beer. Accuracy and repeatability were good for the entire amount considered. Once optimised HPAEC PAD for the specific matrix, the second goal of this research was to verify the possibility to discriminate beers, depending on their style. The carbohydrates content of brewpub commercial beers was very variable, ranging from 19.3 to 1469mg/L (mannose), 34.5 to 2882mg/L (maltose), 141.9 to 20731mg/L (maltotriose), 168.5 to 7650mg/L (maltotetraose), 20.1 to 2537mg/L (maltopentaose), 22.9 to 3295mg/L (Maltohexaose), 8.5 to 2492mg/L (maltoeptaose), even in the same style of beer. However, the carbohydrates content was useful, jointed with other compounds amount, to discriminate different styles of beer. As a matter of fact, principal component analysis put in evidence beer differences considering some fermentation conditions and colour.

Temperature dependence of thermal diffusion for aqueous solutions of monosaccharides, oligosaccharides, and polysaccharides.[Pubmed: 22735314 ]

Phys Chem Chem Phys. 2012 Aug 7;14(29):10147-53.

METHODS AND RESULTS:
We studied the thermal diffusion behavior for binary aqueous solutions of glucose, maltotriose, Maltohexaose, pullulan, and dextran by means of thermal diffusion forced Rayleigh scattering (TDFRS). The investigated saccharides with molar masses between 0.180 and 440 kg mol(-1) were studied in the temperature range between 15 and 55 °C. The thermal diffusion coefficient D(T) and the Soret coefficient S(T) of all solutions increase with increasing temperature. For Maltohexaose and the polymers the thermal diffusion coefficient changes sign from negative to positive with increasing temperature, whereas glucose and maltotriose show only positive values in the entire investigated temperature range. While we were able to find a master curve to describe the temperature dependence of D(T), we were not able to find a similar expression for S(T).
CONCLUSIONS:
This comprehensive study allows for the first time the determination of the interaction parameters for the polymer and the solvent within the theoretical framework suggested by Würger.