title: Organic acid contents in onion cultivars (Allium cepa L.).
abstract: The following organic acids (glutamic, oxalic, pyruvic, malic, tartaric, citric, and fumaric), pungency, Brix degree, acidity, and pH were determined in onion cultivars (Texas, Guayonje, San Juan de la Rambla, Carrizal Alto, Carrizal Bajo, and Masca) harvested in the same agroclimatic conditions. Glutamic acid was the most abundant organic acid (325 +/- 133 mg/100 g) followed by citric acid (48.5 +/- 24.1 mg/100 g) and malic acid (43.6 +/- 10.4 mg/100 g). There were significant differences between the onion cultivars in the mean concentrations of all of the analyzed parameters. The San Juan de la Rambla and Masca cultivars presented, in general, higher concentrations of the organic acids than the other cultivars. Significant differences in most of the analyzed parameters were observed between the two seed origins for the Masca and San Juan de la Rambla cultivars. The onion samples tended to be classified according to the cultivar and, in the case of San Juan de la Rambla cultivar, according to the precedence of the seeds after applying discriminant analysis.
authors.affiliation: Department of Analytical Chemistry, Food Science and Nutrition, University of La Laguna, Avda. Astrofísico Francisco Sánchez s/n, 38201, La Laguna, Santa Cruz de Tenerife, Spain.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Rodríguez Galdón
authors.forename: Catalina
authors.initials: C
authors.lastname: Tascón Rodríguez
authors.forename: Elena
authors.initials: E
authors.lastname: Rodríguez Rodríguez
authors.forename: Carlos
authors.initials: C
authors.lastname: Díaz Romero
mesh_terms: D002264:Carboxylic Acids / Q000032:analysis*; D019343:Citric Acid / Q000032:analysis; D018698:Glutamic Acid / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D008293:Malates / Q000032:analysis; D009812:Odorants / Q000032:analysis; D019697:Onions / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry; D013030:Spain
chemical_list: D002264:Carboxylic Acids; D008293:Malates; D019343:Citric Acid; D018698:Glutamic Acid; C030298:malic acid