A multilevel investigation supported by multivariate analysis for tomato product formulation

Industrial processing of tomato includes its cutting and mincing, thermal treatments, and the addition of ingredients, which might induce changes in physicochemical properties of the final products. In this frame, the impact of texturing/thickening [xanthan gum (X) or potato fiber (F)] on the macroscopic, mesoscopic and molecular properties of tomato double concentrate (TDC) was investigated to determine if F can efficiently substitute X, in association with small solutes (sugar and salt) and thermal treatment (cold and hot). At a macroscopic level, multivariate statistics (MANOVA) underlined that color change (ΔE) was increased by X and F addition contrary to heating and the addition of salt and sugar. MANOVA revealed that texture was greatly enhanced through the use of F over X. 1H NMR molecular mobility changes were more controlled by texturing agents (F and X) than thermal treatment and small solutes. Particularly F increased the more rigid population indicating stronger interaction with water molecules resulting in shear-thinning flow. However, adding X contributed into the increase of the dynamic and mobile populations. Therefore, F can be a valid “clean label” substitute of X in modulating tomato products properties.

Effects of ingredients and cooking time on total phenolic content and antioxidant activity of different homemade tomato sauces

Tomato is one of the most consumed fruits in the world. Tomato sauce, a tomato product, is one of the mother sauces that has been developed by Escoffier (1846-1935). Nowadays, tomato sauce has been adapted by each country according to their own culinary culture. In the current study four different tomato sauce recipes were investigated in the context of their antioxidant activity and total phenolic content. Hydrophilic and lipophilic extractions of samples were evaluated separately. It was found that there is a relationship between total phenolic content and antioxidant activity in hydrophilic extraction. However, no similar correlation was found between total phenolic content and antioxidant activity in lipophilic extraction. According to the results, the highest antioxidant activity of both hydrophilic and lipophilic extractions was observed in S1 with the values 25.53±1.01 and 45.48±2.06 respectively. In lipophilic extraction, S2 had the lowest antioxidant activity with 32.77±1.07, because of the lack of the ingredients high in lipophilic antioxidant compounds. It was observed that the shortest cooking time with 10 min provide the highest retention of antioxidant activity and total phenolic content in this sauce. Also, antioxidant activity of lipophilic extraction for longer cooking time applied sauces (S4) could be kept high with ingredients such as carrot. It can be suggested that adding of ingredients which have antioxidant activity may be useful for providing bioactive properties in long cooking time procedures and it should be noted that the length of cooking time negatively affected the TPC values.

Experimental Measurement of Isothermal Sorption, Microbiological and Physicochemical Analysis of Dried Tomatoes Cultivated in Adrar, Algeria

The fresh tomato is a very perishable product in arid regions for that the drying is an indsipendable technique to preserve this product and used at all times, in this study the fresh tomatoe was sampled from different farms in Adrar and subjected to the drying method using an indirect dryer solar. The dried tomatoes were screened for microbiological and physicochemical analysis including E. coli, Staphylococcus aureus, Salmonella Typhi, anaerobic sulfito- redactors, molds and yeasts in addition, the value of pH, water activity, dry matter, and assay of ash. The obtained results showed the presence of mesophilic aerobic total bacteria, and coliform total, the absence of Salmonella Typhi, Staphylococcus aureus, Clostridium perfringens and spores of anaerobic sulfito reducting and some colonies of yeasts, for the pH value, activity water, dray matter and assay of ash, the results were (4.10), (0.41), (9.63%) and (5.71%) respectively, which do not affect the final quality of the dried products and satisfactory to norms imposed by the commercial legislation of Algerian. On the other hand, the isothermal sorption is indispensable step to mastering the process of drying tomatoes, and to know the distribution and the intensity of the water connections in the products as a result, this experimental study aims to determine the physicochemical components' and the desorption isotherms curves for tomato harvested from the Touat region, in South-West Algeria, using the saturated salt solution method. The experiment is carried out for three temperature values 40℃, 50℃ and 60℃, to study the influence of the temperature on the equilibrium curves of the product and finally to describe the isothermal moisture desorption for tomato product for three temperatures using known models of GAB, GAB, modified BET who showing the best models isotherms sorption to model at and predict hygroscopic behavior during drying and storage. The results of this research can be used to determine characteristic drying curves and to have optimal storage conditions.

Development of Mango and Tomato Paste and It's Physico-Chemical Characterization

Mangoes are most widely used in cuisine. The Soil requirement for cultivation of Mango tree is a hardy perennial and evergreen tree and it can be grown on a wide range of soils. Value added product such as Milk Shakes can be obtained from fresh pulp of Mango which acts as an excellent source of Vitamin-A and flavonoids. Similar to that high quality Tomato product can be prepared from tomato pulp by using uniformly ripened, red colour tomato. Thus Tomato is nutritious and mostly eaten as processed fruit. So the importance of Climatic Fruit in food industries for the manufacturing of value added Product has received great attention. So the objective of present study is to analyse the composition of mango and tomato and to develop the pulp, and also to know its shelf life which favour the health benefits.

Response surface methodology assessment of osmotic pre-drying and convective dehydration processes on the anti-oxidant property of Hausa variety of tomato

This study was conducted to determine the effect of osmotic pre-drying treatment on the vitamin C content of Hausa variety of tomato. The tomatoes used were sliced to a uniform diameter of 10 mm, deseeded and then osmotically pre-treated with sugar and honey solution at different osmotic concentrations (20, 30, 40, 50, 60 °Bx), osmotic time (10, 20, 30, 40 and 50 min) and osmotic temperature (10, 20, 30, 40, 50 °C). Experimental design was done using the Central Composite Design (CCD) methodology of Design Expert software version 6.0.6. Drying of the samples was done at 65 °C in a cabinet dryer operating mainly on convectional heat transfer. Drying process was completed and terminated when the samples reached their equilibrium moisture content between 3-5% after total drying time of 10 hours. The data obtained were analysed statistically using analysis of variance (ANOVA) and regression analysis at p≤0.05 significance level. The developed model was significant and has goodness of fit with an R2 value of 71.29% and lack of fit test was insignificant at p≤ 0.05. Optimized process conditions for producing the best quality of tomato product with vitamin C content of 22 mg/100 g were 35.43 °Bx osmotic concentration, 11.10 min osmotic time and 23.86 °C osmotic temperature having a desirability function of 1. These conditions were considered to be advantageous as they were more economical, time and energy saving.