IMPACT OF OSMOTIC DEHYDRATION ON QUALITY OF TOMATO SLICES

Document Type : Original Article

Authors

1 Special Foods Dept., Food Techol. Res. Inst., Agric. Res. Cent., Giza, Egypt

2 Food Sci. Dept., Fac. Agric. Zagazig Univ., Egypt

Abstract

This work was carried out to study the effect of three mixture immersion solutions on the quality of osmotic dehydration of tomato (Solanum lycopersicum) slices. The first mixture was sugar syrup 30°Brix, 50° Brix and 60° Brix. The second mixture was sugar and calcium chloride (CaCl2) (500ppm) in sugar syrup 30° Brix, 50° Brix and 60° Brix. The third blending 10% salt (NaCl) in sugar syrup 50° Brix as osmotic agents on osmotic dehydration of tomato slices with immersion duration (6 and 8 hours) at constant tomato ratio of (1:4). After this step the tomato slices in three mixtures were laid on the drying cabin for sun drying of tomato at 30 - 45°C. The moisture content and some chemical properties such as (total soluble solids TSSo Brix, total titratable acidity TA (%) and pH-value) of tomato slices were determined. The results obtained showed that the lowest pH value was obtained from the treatment with 50° Brix sucrose with NaCl 10% (3.18), the highest content of total soluble solids was obtained from the treatment with 50° Brix sucrose with NaCl 10% and the highest total titratable acidity treatment was due to reatment with 50° Brix sucrose with NaCl 10% (0.720) consequently, the best treatment was that of 50° Brix sucrose with NaCl 10%. There were high significant differences between it and other treatments. From the obtained results, it could be concluded that the osmotic dehydration have highly impact on the quality control of tomato slices. 

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