Chemometric Studies of Chemical Compounds in Five Cultivars of Potatoes from Tenerife

Abstract

A statistical study of correlation and multivariate analysis on the chemical composition of five cultivars of potatoes harvested in Tenerife was carried out to establish the relationships between the chemical compounds and, therefore, to differentiate the samples according to traditional and recent importation potatoes, cultivars, and species/subspecies. A large number of significant correlations between the chemical compounds were found, which suggests biochemical relationships among them. After factor analysis, the dimension space was reduced from 24 variables to eight factors, accounting for 77.2% of the total variance. Starch, moisture, organic acids, and metals are the variables that make it possible to characterize the system without losing very much information. Total differentiation of potato samples according to the criteria species/subspecies and cultivars was obtained using discriminant analysis with all the variables. However, with only four variables (weight of tuber, starch, amylose, and glucose + fructose) it is possible to differentiate between the traditional and recent importation potatoes.

Assessment of growth, yield, tuber quality and profitability of potato upon boron fertilization

“…The total titratable acidity was determined by volumetric procedure (AOAC, 2000). Ascorbic acid (Vitamin C) content of the potato was estimated by using 2, 6 di-chlorophenolindophenol dye titration method (Casanas 2002). The total soluble sugar and total starch (dry weight basis) of potato tuber was determined by universal anthrone reagent method as stated by Sen (2006).…”

Effect of Foliar Application of Micronutrients on Antioxidants and Pungency in Onion

“…Chemical analysis Non-enzymatic antioxidants Analysis of ascorbic acid content (AAC) One gram of finely chopped onion tissue was extracted with 20 ml of 4% oxalic acid following maceration in a pestle and mortar and the material centrifuged for 30 min at 10,000 g. Ascorbic acid content was determined using the dichlorophenol indophenol titration procedure (Casanas et al, 2002).…”

Composición Química De Cultivares Locales De Castañas De Tenerife: Ii. Composición Mineral Chemical Composition of Local Chestnut Cultivars in Tenerife Island: Ii. Mineral Composition

“…También es importante la ingesta de K (11 % de la ingesta diaria recomendada a un adulto), de Mg (12 % y 16 % de las cantidades recomendadas en hombres y mujeres respectivamente), y de P con un 9 % de la ingesta propuesta para adultos. Si se calcula la relación entre los contenidos de Na y K se observa que es 6,0 · 10 -3 , valor inferior a los descritos para otros alimentos vegetales como patata (Casañas et al, 2001) o higo pico (Díaz Medina et al, en prensa), y ligeramente superior que el encontrado en plátano (Forster et al, 2002). Esto tiene interés desde un punto de vista de nutrición y salud, ya que muchos estudios epidemiológicos y fisiológicos han sugerido que una alta relación Na/K en la ingesta de un individuo puede estar asociado a un mayor riesgo de hipertensión y enfermedad cardiovascular (Krummel, 2000).…”

“…La determinación de los minerales y elementos traza se realizó por espectrofotometría de absorción atómica (EAA), previa digestión de las muestras siguiendo el método descrito por Casañas et al (2001) y Forster et al (2002). Se pesaron aproximadamente 2 g de muestra seca de castaña (precisión de 1 mg) y se depositó en tubos de digestión a los que se añadieron 6 ml de HNO 3 concentrado Hiperpure (Panreac).…”