Quality Parameters Of Tomato Research Articles

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

The alcobaça mutation in the Penjar tomato (Solanum lycopersicum L.) variety alters the ripening process and confers a long shelf life (more than four months). Storage of Penjar tomatoes leads to a distinctive sensory profile valued by local consumers, who prefer aged tomatoes to fresh ones. To study chemical changes occurring during storage, we characterized the complete sugar-and-acid profile of 25 accessions at harvest and at 2 and 4 months after harvest. We found considerable variability in the sugar-and-acid profile within the Penjar variety, especially for fructose and glucose. Some accessions presented exceptionally high values for sugars, making them especially interesting for breeding programs. During postharvest, the concentration of glucose, fructose, and citric acid decreased, whereas the concentration of malic and glutamic acids increased. Data from this study offer novel insights into postharvest changes in tomato quality parameters and help elucidate the reasons for the appreciation of this variety by consumers.

Quality attributes, moisture sorption isotherm, phenolic content and antioxidative activities of tomato (Lycopersicon esculentum L.) as influenced by method of drying

Drying behavior, moisture sorption isotherm (MSI), glass transition temperatures (Tg) and different quality parameters of tomato (Lycopersicon esculentum L.) as affected by drying (sun and solar) was investigated. Drying of tomato under sun displayed a higher rate of moisture loss than those dried in solar drier. However, both the samples finished the drying process after 52 h. Sun and solar dried tomatoes displayed a Tg of −12 °C. When tested against different water activities (Aw), Tg decreased with an increase of Aw. MSI revealed that the relation between Aw and moisture content was found to be exponential (y = 15.959e1.5175x, R2 = 0.9944). Analysis of different quality parameters and antioxidative activity revealed that drying process was known to decrease lycopene, vitamin C, total phenolic and flavonoid content as well as decreased activities was displayed in different antioxidative assays when compared to fresh tomato. Among the samples dried under sun and inside solar drier, there was no significant difference in lycopene and vitamin C content (p < 0.05). However, total phenolic and flavonoid content was higher in solar dried samples. Moreover, antioxidative activity also did not display any difference between the two samples (p < 0.05). More importantly sensory evaluation showed that consumer panelist preferred sun dried samples over solar dried samples. Sun dried sample were more bright red in color with higher a* and L* values than solar dried samples which were darker in color. Therefore, sun drying with some modification can be a promising technique to preserve the perishable tomato and can be effective in preventing the quality losses during drying.

Growth and comprehensive quality index of tomato under rain shelters in response to different irrigation and drainage treatments.

The effects of two levels of irrigation water (100%, 60%) and buried underground pipe depths (0.8 m, 0.6 m) under rain shelters' conditions on yield and some quality parameters of tomato were investigated. A fully randomized factorial experiment was conducted between April and August in 2011 and 2012 at Hohai University. It was found that drainage treatments enhanced biomass production, whereas soil desiccation led to biomass reduction. At 60 cm buried underground pipe depths, the drought treatments increased the mean root weight and root-shoot ratio by 14% and 39%, respectively. The main effects of drainage treatments on the fruit quality were increases in total soluble solids (TSS), soluble sugar (SS), and vitamin C (VC) compared to the control. In addition, drainage treatments increased the average yield by 13% and 9%, respectively, in both years. The drought treatments did not significantly alter fruit yield, although mean single fruit weight was slightly reduced. Instead, these treatments tend to have great potential to improve fruit quality (TSS, SS, and VC) to variable extents. In both years, the drought treatment at 60 cm buried underground pipe depths proved to possess the highest comprehensive quality index based on Principal Component Analysis.

Effect of Applied Magnesium on Yield and Quality of Tomato in Alfisols of Karnataka

Field experiments were conducted for two years on Alfisols to assess the effect of applied magnesium on fruit yield and quality parameters in tomato. Magnesium was applied at four levels ranging from 0 to 100 kg/ha in the form of MgSO4. Applied Mg significantly enhanced fruit yield up to 50kg /ha during the two years of experimentation. Tomato quality parameters viz., total titrable acidity, content of lycopene, total carotenoids and ascorbic acid differed significantly among treatments. Applied Mg significantly improved quality. Highest lycopene content, carotenoids and ascorbic acid in the fruit was recorded in Recommended Dose of Fertilizers (RDF) + MgSO4 @ 50Kg/ha followed by RDF + MgSO4 @ 75 kg/ha. Lowest values for the above parameters were observed in the treatment receiving RDF alone in both the years.

Nondestructive Measurement of Fresh Tomato Lycopene Content and Other Physicochemical Characteristics Using Visible−NIR Spectroscopy

Measurement of fresh tomato fruit overall quality, and particularly lycopene content, is challenging in the context of high-volume production. An experiment was conducted to simultaneously measure various quality parameters of tomato in a nondestructive manner using vis-NIR reflectance spectroscopy and chemometrics. The sampling set included different cultivars that are obtainable from both retailers' shelves and two greenhouse producers. Results indicate that lycopene content was accurately predicted [r(2) = 0.98; root mean square error of cross-validation (RMSECV) = 3.15 mg/kg], along with color variables such as Hunter a (r(2) = 0.98), L, and b (r(2) = 0.92). Tomato color index (TCI) was better predicted (r(2) = 0.96) than the a/ b ratio (r(2) = 0.89). Firmness prediction, with an r(2) of 0.75, is comparable to what is reported in the literature for other fruits and may have a practical interest. Prediction of internal quality such as pH, soluble solids, titratable acidity, and electrical conductivity was less accurate, partly due to a low variability of these parameters among samples. Predictions were robust with regard to cultivars, except for pink variety tomato. The 400-1000 nm range gave results almost as accurate as the 400-1500 nm range.