Validation of a HPLC method for simultaneous determination of main organic acids in fruits and juices

Abstract

a b s t r a c tA liquid chromatographic method for fast and simultaneous determination of tartaric, malic, ascorbic and citric acids was validated for further application to fruits and juices. Moreover, the organic acids content of commercial samples of fruits and juices were evaluated, as well as the ascorbic acid stability during the storage. Determination of organic acids was carried out using a liquid chromatograph coupled to a diode array detector, with reversed phase (C 18 column) and isocratic elution with 0.01 mol L À1 KH 2 PO 4 (pH = 2.60) mobile phase. The validation parameters showed efficiency, adequate linearity, relative standard deviation values between 0.4% and 2.3% (n = 10) for repeatability and from 1.2% to 5.0% (n = 18) for reproducibility, limits of detection (LD) were between 0.03 and 3.31 lg mL À1 and quantification (LQ) were between 0.10 and 11.03 lg mL À1 , recovery rates were between 82% and 110%, for two levels. In addition, the method is fast (10 min) and generates low and non-toxic residues. The values found for vitamin C were about 10 times above the values declared at the package. Ready to drink juices have a composition similar to the fruit, concerning to organic acids, except for the powder juice, in which only ascorbic and citric acids were found, for all tastes. After opening the package, a decrease of 14.0% and 27.0% in ascorbic acid content was observed for orange powder and ready to drink juices, respectively.

Optimization and Validation of a Reverse-Phase High Performance Liquid Chromatography Assay with Ultra-Violet Detection for Measuring Total L-Ascorbic Acid in Food and Beverage Products

“…Samples showed good preservation of L-AA at -80°C for up to two months. These findings are in agreement with Scherer et al [38] who reported stability of L-AA in fruit juices stored at 5°C for at least the first two days. Significant (p<0.05) losses of vitamin C content during the freeze-thaw cycles in the current study were in agreement with some other studies that reported similar losses during the thaw-out process, despite a slight variation in storage and temperature conditions [39][40][41].…”

Effect of thermal treatment and storage on bioactive compounds, organic acids and antioxidant activity of baobab fruit (Adansonia digitata) pulp from Malawi

“…The mean vitamin C content (AA + DHA) measured in the fresh baobab pulp (467 ± 8.1 mg/100 g FW) is more than eight fold higher than commonly consumed raw navel oranges (56.1 ± 1.0 mg/100 g) and raw lemon juice (42.9 ± 0.4 mg/100 g) reported by Scherer et al (2012). However several authors have reported a wide range of vitamin C content (67 to 500 mg/100 g) in fresh baobab pulp (Chadare et al, 2009;Ibrahima et al, 2013;Kamatou et al, 2011;Tembo, 2008).…”

“…Variation in composition of plant foods is attributed to several factors including species, environmental conditions, ripening stage at harvest, postharvest handling, storage condition and analytical techniques used (Aron and Kennedy, 2008;Tembo, 2008). For instance, Chadare et al (2009) reported an average vitamin C content of 283 mg/100 g pulp but also noted the tree-to-tree variability ranging from 150 -500 mg/100 g. Titrimetric or spectrophotometric methods of measuring vitamin C are unstable and not accurate due to inaccuracies in determining end points and interferences in sample matrix (Scherer et al, 2012). The use of a selective and sensitive method (RP-HPLC-PDA) in the present study ensures accurate quantification of quality attributes in baobab fruit products.…”

The Effect of Potassium Biofortification Over Yield and Nutritional Quality of Cherry Tomato Fruits

“…The determination of organic acids was based on the method of Scherer et al (2012) with slight modifications and was performed using HPLC with a DAD UV-visible detector (Agilent Technologies, USA) under the following conditions: Phenomenex reverse-phase column, 250×4.6 mm i.d., 5 μm, LiChrospher 100 RP-18, with a 4×4 mm i.d. guard column of the same material (Luna, Phenomenex, Utrecht, Belgium).…”