Showing 5 results for A. Mortazavi
A. M. Maskouki, A. Mortazavi,
Volume 8, Issue 2 (summer 2004)
Abstract
The inhibitory effects of thyme and ajowan oils on growth of A. parasiticus on pear during cold storage were studied. The main components of the two essential oils are phenolic compounds such as thymol and carvacrol with antimicrobial properties. Pear samples were inoculated by suspension ( 106 spor/ml) of A. parasitcus spores and sprayed by thyme (200 p.p.m) and ajowan (300p.p.m) separately and kept in cold storage (0 ±10C and relative humidity of 85%). Organoleptic test for evaluating oil odor residue was studied after 3 months. The amount of spoilage and contamination of pear fruit in 1st, 2nd, and 3nd month after cold storage was determined and were data the statistically analyzed. The results showed that in spite of the higher thymol content in ajowan oil constituent, which is well known as an antimicrobial agent Stronger than thyme oil, thyme oil at 200 p.p.m was more effective than ajowan oil in controlling and preventing, A.parasiticus growth in pear. It seems this is due to synergistic effects of other phenolic compounds such as carvacrol which does not exist in ajowan oil. The results of organoleptic test showed that the samples treated with ajowan oil have more acceptance than those treated with thyme oil thie applied even to the control sample. According to the results, thyme and ajowan oils are good promising natural antifungal agents without any hazardous effects on human health and can be successfully use as chemical fungicides.
M. R.edalatian, S. A. Mortazavi, M. Hamedi, M. Mazaheri,
Volume 9, Issue 4 (winter 2006)
Abstract
Production and consumption of whole tomato and/or its products(tomato paste, tomato juice, ketchup, etc) is incearsed all over the world. Annual production of tomato in Iran is about 3.4 million tons (MT), part of that is processed in the tomato paste factorise, which are mostly located in khorasan province. Since tomato variety has a determinant effect on the physico-chemical and organo leptical properties/quality of tomato and its products, an investigation was performed to evaluate the impact of variety and storage time of four tomato varieties, Cal.j.n.3, Early Urbana Y, Early Urbana 111and Peto early C.H which were selected according to a national project and were monitored according to their brix, pH, Acidity, Sugar and Salt contents, total and non soluble solids. Results indicated that Early Urbana 111 and Peto early C.H contained the highest amounts of soluble solids along with the highest pH. Also it was evidenced that these varieties were the most stable varieties as the least compositional changes was seen in them.
S. M. A. Razavi, S. A. Mortazavi, S. M. Mousavi,
Volume 10, Issue 2 (summer 2006)
Abstract
In this study, the effect of transmembrane pressure (TMP) on flux decline and protein rejection due to concentration polarization and fouling (adsorption) resistances during ultrafiltration of reconstituted skimmilk was investigated. UF experiments were carried out using a pilot plant unit equipped with spiral wound module and polysulfonamide UF membrane. A three-stage experimental strategy based on a resistance-in-series model (boundary layer-adsorption) was used to seperately determine the hydraulic membrane resistance, concentration polarization and fouling resistances. The results showed that increasing TMP had no effect on initial flux reduction (Jrt), but flux decline in each TMP was greatly due to concentration polarization, and fouling has a small role in flux decline, whereas dynamic response of flux decline proved that increasing Jrt during operation is due to fouling. The influence of TMP on resistances showed that total hydraulic resistance and reversible fouling resistance are increased with increasing TMP, but intrinsic membrane resistance and irreversible fouling resistance did not change. Increasing the total hydraulic resistance with time resulted in increasing both reversible and irreversible fouling resistances. Increasing TMP or operation time had no significant effect on protein rejection, but only led to an increase about 1-4 percent.
A. Koocheki, S. A. Mortazavi, M. N. Mahalati, M. Karimi,
Volume 10, Issue 3 (fall 2006)
Abstract
In order to determine the effects of emulsifiers (Lecithin, E471 and E472) and their levels (0, 0.25, 0.5, 0.75 and 1%) and also addition of fungal α-amylase (0, 5, 10 and 20 g/100 kg flour) on bread staling, a completely randomized experiment with factorial design and 3 replications was conducted. Bread staling was determined after 0, 24, 48 and 72 hours of storage. Correlation between variables was analyzed by simple and multivariate regression. Results indicated that addition of emulsifiers reduced the firmness of bread. E472 had the most and E471 had the least effect on bread firmness after 72 hours of storage. Addition of α-amylase reduced the bread firmness and this effect was less pronounced after 72 hours of storage. Correlation between variables based on the development of a model showed that in the first day of bread production, optimal levels of emulsifiers were 1%, 0.25% and 0.5% for Lecithin, E471 and E472, respectively. In case of simultaneous application of emulsifiers and enzyme, the optimal level of enzyme was 5 g/100 kg flour.
Sh. Dokhani, S. Jafarian, Gh. Kabir, A. Mortazavi Beck,
Volume 11, Issue 1 (spring 2007)
Abstract
To determine the preheating effect on frozen French - fries quality, four potato cultivars: Agria, Marfona, Auozonia & Auola were selected from Faridan region in Isfahan province & transferred to cold storage at
temp.=5+0.5°C and RH=85-90%. At first, some physico – chemical characteristics of potato tubers such as specific gravity and dry matter content were measured by A.O.A.C methods. Also reducing sugar contents were analyzed by “High Performance Liquid Chromatography” (HPLC). The potato strips were blanched in hot water at different condition: 70°C - 4 min, 70 °C 10 min, 95 °C - 2min and then deep - fat fried at temperature 175°C for 2 minutes. Product quality properties such as texture, color and oil absorption were determined by standard methods. The data were analyzed using a factorial experiment in a completely randomized design, and average comparisons were made by by Duncan's multiple range test (p < 0.01). The results showed that blanching at 70 °C for 10 minutes markedly improved the quality parameters. Treatment at 95 °C – 2 min did not have any significant effect on Hunter Lab color parameters compared with 70 °C – 10 min. treatment, but the texture was significantly different. The oil absorption increased in strips blanched at 95 °C for 2 minutes. The samples blanched at 70 °C – 4 min had no significant effect on the product quality. In conculsion, Agria &Auola cultivars were more suitable for manufacturing French - fries than the other two varieties.
