Micellar-enhanced ultrafiltration for the recovery of lactic acid and citric acid from beet molasses with sodium dodecyl sulphate

Colour removal from beet molasses by ultrafiltration with activated charcoal

“…The sucrose content of the molasses was measured by polarimetry at 880 nm using an Anton Paar MPC500 Sucromat polarimeter with a precision of ± 0.01 ºZ and reproducibility of ± 0.01 ºZ [7]. The colour of the feed molasses, decolourized molasses and exhausted charcoal regeneration solutions was determined spectrophotometrically at 475 nm using a Hitachi U-2000 spectrophotometer [21].…”

“…The colour of the feed molasses, decolourized molasses and exhausted charcoal regeneration solutions was determined spectrophotometrically at 475 nm using a Hitachi U-2000 spectrophotometer [21]. Total concentrations of betaine, lactic acid and citric acid in the molasses (feed and decolourized) were determined by liquid chromatography using a Beckman System Gold HPLC [7]. A reverse phase column ACE 5C18 (ACE HPLC columns), and a UV-vis detector at 216 nm were used.…”

“…This byproduct of sugar-beet processing plants is a highly viscous, dark brown syrup, which is characterised by a high content of fermentable sugars (50-55 wt.%) and several non-sugar organic compounds, such as betaine, lactic acid, amino acids, minerals, phenolic compounds, and dark colour compounds (6 wt.%) [1,[5][6][7]. At least 80% of the colour of beet molasses is provided by melanins, melanoidins and hexose alkaline degradation products (HADPs), which can take part in sucrose hydrolysis and in many complex reactions such as Maillard reactions, with the formation of new melanoidins, and different polymerization reactions [2,6,8].…”

“…At least 80% of the colour of beet molasses is provided by melanins, melanoidins and hexose alkaline degradation products (HADPs), which can take part in sucrose hydrolysis and in many complex reactions such as Maillard reactions, with the formation of new melanoidins, and different polymerization reactions [2,6,8]. Removal of the dark colour compounds can be highly profitable in order to avoid changes to the composition and colour of beet molasses during storage and use [1,3,7]. above 300 °C is usually used in thermal method [15] and water [11,18,19], sodium hydroxide solutions [19,20] or various alcohols [18,19] as desorption agents in chemical methods.…”

Reactive Extraction of Citric Acid Using Different Extractants: Equilibrium, Kinetics and Modeling

“…Kinetics experiments for citric acid extraction were performed in a Lewis-type stirred cell that was designed similar to that used by Wasewar et al 18 and Gaidhani et al 19 The cell was configured with a flat bottom with 6.5 cm inner diameter, and having total interfacial area of 33.18 cm 2 . The stirred cell was firstly filled with 100 mL aqueous solution of citric acid of different concentrations.…”