farnaz dastmalchi

 Gluten-free breads based on flour and starch, have low quality in terms of textural and sensory characteristics as well as nutritional value. By using 2 types of starch (corn and potato starch) and 3 types of plant protein isolate (sesame, soy and pea), studies were conducted to find the best gluten-free bread formula with appropriate textural, sensory and nutritional quality. In the first stage, between corn and potato starch, the formula with potato starch had higher volume, lower weight loss and porosity. In the second stage, among the three formulas with different protein isolates, the bread with 7% sesame protein isolate showed less hardness and chewiness and higher cohesiveness in 24 and 48 hours after baking. In all sensory evaluation factors with a 5-point hedonic scale except color (4.5 ± 0.8), the score of bread with sesame isolate was higher, and only bread with soy protein isolate had a higher color score (4.9 ± 0.7). The colorimetric characteristics, protein content, decrease in weight loss and moisture content of gluten-free bread increased significantly with the addition of protein isolate compared to bread formulas without protein isolate (P<0.05).

The usage of plant extraction such as tannins, flavonoids & et. as an alternative to fungicidal effects. The aim of this study was to evaluate of  the antifungal effect of Iranian oak Jaft extract after extraction by different methods on Penicillium italicum and (Penicillium digitatum as an indicator of citrus fruit mold spoilage. molds were expossered by different concentrations of oak Jaft extract. The investigated factors including minimum inhibitory concentration (MIC) (mg/ml), minimum lethal concentration (MFC) (mg/ml) and non-growth diameter (mm) were determined by the methods of tube dilution, surface culture and diffusion in agar well (WD). The results showed that different concentrations of aqueous extract had significantly effect (p<0.05) on the non-growth  diameter of molds. The antifungal effect was significantly (p<0.05)increased in concentrations of 40 and 80 mg/ml aqueous extract. In this research, Fludioxionil 25%  poison as a control group showed a significant difference(p<0.05) in molds growth. In general, the extract of Iranian oak Jaft can be used to control the fungal spoilage of citrus fruits.

In this study, in order to investigate the natural colorants of black tea, various test methods were developed and set upped. For this purpose, methods for measuring natural tea pigments, polyphenols, synthetic dyes, some metals and the pH of the extract were developed. The results of measuring natural tea pigments showed that Iranian tea has higher natural pigments (chlorophyll, pheophytine and their derivatives) than foreign tea. The results of analysis of polyphenols showed that foreign tea compounds have higher polyphenolic compounds and therefore the colour of the extract was much richer than the colour of Iranian tea extract. Examination of synthetic colours also showed that there is no synthetic colour in any of the foreign or Iranian tea samples. Heavy metal testing with ICP-OES also showed that foreign tea has more metals, especially aluminium, than Iranian tea. Also, measuring the pH of Iranian and foreign brewed teas showed that the extract of foreign teas is more acidic than the extract of Iranian teas. According to the results, it can be concluded that the origin of the difference in the colour of brewed tea extract is primarily due to the variety of tea itself and its proper processing and fermentation process, which can lead to higher formation of theaflavins and thearubigins (natural red pigments). On the other hand, high concentrations of aluminium and polyphenolic compounds in foreign tea can also lead to the formation of coloured complexes (orange to red) and more colourful tea colour.