StatusThe thesis was presented on the 3 December, 2010
Approved by NCAA on the 24 February, 2011
Abstract– 0.33 Mb / in romanian
Physico-chemical and sensorial properties of fruit composites with reduced sucrose content”, specialty 05.18.01 – Food Technology (Canned Food Technology), city Kishinev, 2010. Thesis structure: introduction; four chapters; general conclusions and recommendations; bibliography of 235 titles; 5 annexes (104 basic text pages, 29 figures, 39 tables). The obtained results are published in 7 scientific papers.
Sensorial properties and the nutritional value of plums or cherry jam and comfiture were evaluated in dependence on the sucrose content. The functional correlation between physico-chemical properties of fruit composites with sucrose and the taste sensations of jam and comfiture, expressed by the mathematical correlation in numeric values, equivalent to the sweet taste order of sucrose were established.
It was determined, that taste sensations of finite products are in function of physico-chemical characteristics of fruits: the content of hydrosoluble dry substances, total acidity, pH value, thermal treatment parameters and the sucrose concentration. The numeric values of taste vary in the limits of 15,0-22,0 and cover sensations, beginning with the sour taste and finalizing with excessive sweet taste. It was estimated, that the jam and comfiture obtained from compositions with the ratio fruits:sucrose=1:0,3-0,5 with numeric values of the sweet taste order Gd=16,5-19,0, show sensations of harmonized taste, appreciated by sensorial analysis.
The fabrication technology of jam and comfiture of plums and cherry, that provides the reduction of sucrose consumption up to 25,0-40,0% and the majority of fruits composition in the composition of finite products up to 20,0-36,0%, in comparison with the traditional technology, was elaborated.
It was determined that the microbiological stability of jam is assured by pasteurization with the necessary lethal effect of 2,47-2,54 min, for t=1000C, referring to the Byssochlamys Nivea strain from fungi class. The stability duration exceeds 1 year. It was determined, that the validity duration of biological value of plums and cherry jam depends on the content and stability of flavonoids, that consists 90-160 days, expressed by the oxido-reductive state index. It was demonstrated, that the modification of the oxido-reductive state and the optic density of plums jam takes place involving the same chemical compounds of flavonoids class with identical probability.