Citric acid

About: Citric acid is a research topic. Over the lifetime, 17745 publications have been published within this topic receiving 277125 citations. The topic is also known as: citrate & H3cit.

Catalytic Mechanism of Lipid Oxidation following High Pressure Treatment in Pork Fat and Meat

Abstract: Addition of citric acid (0.02%) inhibited the increased rate of lipid oxidation found in rendered pork fat following pressure treatment (650-800 MPa). This indicated that transition metal ions were probably released from complexes and became available to catalyze lipid oxidation in the pressure treated fat. In minced pork and washed fibers citric acid was less effective in inhibiting oxidation in pressure treated samples because of its pH lowering effects. However, the less acidic ethylenediaminetetraacetic-acid disodium salt (Na 2 EDTA) was an effective antioxidant in these pressure treated (400 MPa and 800 MPa) systems. This further indicated that metal catalysts (probably iron) were released from complexes during pressure treatment to catalyze lipid oxidation.

Human enamel dissolution in citric acid as a function of pH in the range 2.30≤pH≤6.30 – a nanoindentation study

Abstract: The objective of this study was to investigate the dissolution of human enamel in citric acid solutions over a wide range of pH. The in vitro conditions are considered to be relevant to soft drink-induced enamel erosion. Nanoindentation was used to investigate changes in the nanomechanical properties of polished enamel surfaces after exposure to citric acid solutions. Solutions used had 38.1 mmol l-1 citric acid and pH greater than 2.3 but less than 6.3 (2.30 < or = pH < or = 6.30). Samples were exposed to rapidly stirred, constant composition solutions for 120 s. Statistically significant changes in enamel hardness and reduced elastic modulus were observed after exposure to all solutions. There was an approximately linear dependence of enamel hardness on solution pH for 2.90 < or = pH < or = 6.30. Below pH 2.90, enamel is thought to have reached the lowest possible hardness value. The reduction in enamel dissolution caused by an increase in pH of a soft drink is likely to be small. Product modification to reduce the erosive potential of drinks may require additional methods such as addition of calcium salts.

Intake of Ethanol, Sodium Chloride, Sucrose, Citric Acid, and Quinine Hydrochloride Solutions by Mice: A Genetic Analysis

Abstract: Mice of the 129/J (129) and C57BL/6ByJ (B6) strains and their reciprocal F1 and F2 hybrids were offered solutions of ethanol, sucrose, citric acid, quinine hydrochloride, and NaCl in two-bottle choice tests. Consistent with earlier work, the B6 mice drank more ethanol, sucrose, citric acid, and quinine hydrochloride solution and less NaCl solution than did 129 mice. Analyses of each generation's means and distributions showed that intakes of ethanol, quinine, sucrose, and NaCl were influenced by a few genes. The mode of inheritance was additive in the case of ethanol and quinine, for sucrose the genotype of the 129 strain was recessive, and for NaCl it was dominant. Citric acid intake appeared to be influenced by many genes with small effects, with the 129 genotype dominant. Correlations of sucrose consumption with ethanol and citric acid consumption were found among mice of the F2 generation, and the genetically determined component of these correlations was stronger than the component related to environmental factors. The genetically determined correlation between sucrose and ethanol intakes is consistent with the hypothesis that the higher ethanol intake by B6 mice depends, in part, on higher hedonic attractiveness of its sweet taste component.