Changes in organic acids in chilled tomato fruit (Lycopersicon esculentum Mill)

Abstract

A B S T R A C TMature green tomatoes cu Calypso were stored at 5 , 7 , 1 2 or 19°C for 0 , 3 , 9 , 12 or 21 days, then ripened at 19°C for 3 or 6 days before analysis for organic acids, p H and acidity. Citric acid concentration increased after storage at 5 or 7°C and decreased at 19°C. Malic acid decreased at all temperatures with the greatest decrease occurring at 19°C. The maliclcitric acid ratio was 0.32 at 19°C and 0.36 at 12°C. The rate of acetic acid accumulation increased as the storage temperature was reduced. Oxalic acid concentration decreased with time but was greatest at 12°C and lowest at 19°C. Fumaric acid concentration showed similar but erratic trends. Changes in pH were variable, but greater in chilled than unchilled fruit. Titratable and total acidities increased with storage time at chilling temperatures, but decreased at 19°C. Bound acidity initially decreased with time but subsequently increased. Significant differences were found between organic acid concentrations and p H in chilldamaged and undamaged tissue.

Sugar-and-acid profile of Penjar tomatoes and its evolution during storage

“…Contrary to citric acid, malic acid and glutamic acid increased during postharvest. Malic acid is the second most abundant acid in tomato fruit, and in normal tomatoes its content decreases markedly during ripening (Davies, 1966) and more slowly during postharvest (Thorne and Efiuvwevwere, 1988). However, malic acid metabolism is under ethylene regulation; Gao et al (2007) reported increased malic acid during ripening in transgenic tomatoes with suppressed ethylene biosynthesis.…”

Effect of benzyl isothiocyanate on tomato fruit infection development by Alternaria alternata

“…36 pH and TA% were determined using an automatic titrator (Mettler model DL21) standardized at pH 4 as described previously. 37 The TA% is reported utilizing citric acid as standard. TSS, pH and TA were measured every 3 days of storage at 20 • C. The statistical effect of the treatments over the post-harvest physiology and quality of tomato fruit was studied with analysis of variance based on a completely randomized block design in which the blocks were the different sampling time points.…”

Organic Acids Profile in Tomato Juice by HPLC With Uv Detection

“…Their concentration may significantly affect flavor acceptability. The major organic acids in tomatoes are citric and malic, with citric predominating (Davies and Hobson 1981; Thorne and Efiuvwevwere 1988) and their level depends on ripeness and cultivars (Baldwin et al. 1991).…”