Search published articles


Showing 4 results for Mahdi Jafari

Shima Hosseini, Ali Reza Sadeghi Mahoonak, Seyed Mahdi Jafari, Mohammad Ghorbani, Azadeh Salimi,
Volume 13, Issue 59 (0-0)
Abstract

In the present research work, response surface methodology was used to achieve optimum condition to prepare orange peel oil – quince seed mucilage (QSM) and maltodextrin (MD) emulsion and using this emulsion in microencapsulation. For this purpose and in order to access stable emulsion, effect of three independent variables including orange peel oil concentration (15-25% w/w), QSM/MD (0.015-0.02) and solid concentration (QSM+MD)(25-35% w/w) on the three dependent variables including droplet size, creaming index and viscosity were investigated. Optimized emulsion (25% solid concentration, 0.02 QSM/MD and 0.025 orange peel oil concentration) were dried by freeze dryer, and were kept in three temperature (4, 25 and 42 °C) in order to investigation its stability during 6 week storage. The results showed that rheological properties of QSM, in particular its viscosity, had the highest effect on the stability and properties of emulsions and QSM could make quite stable emulsion over time. Also, our results revealed that half-life and release rate of encapsulated samples were significantly lower than control samples.
Tayebe Shahi, Seid Mahdi Jafari Jafari, Mohsen Pouyan, Mahdi Ebrahimi, Hossein Raghara, Sareh Hosseini,
Volume 18, Issue 121 (March 2022)
Abstract

vinegar is a functional and widely used seasoning around the world that is made from various raw materials. Since there are many reports confirming the antioxidant power of vinegar and its use as a fat burner and weight-loss ingredient, so it is necessary to study the composition and characteristics of different types of vinegars. Jujube vinegar was prepared using different treatments and the best product was selected. Traditional grape and apple vinegars and industrial apple vinegar were also purchased from the local market.  physical and chemical tests including acidity, pH, calorimetric, antioxidant capacity, phenolic compounds, sensory and color evaluation were performed on vinegar samples. Based on the results, the minimum and maximum values for pH, acidity, and Brix tests were 2.91 to 3.27, 3.20 to 5.31, and 4.93 to 14.47, respectively.  The highest amount of phenolic compounds (5042.67) and antioxidant activity (32.88%) was observed in jujube vinegar. The lowest color components of L, a, and b were 26.11, -5.20, and 32.21 in industrial apple vinegar, respectively.  The highest and lowest scores of Average Comparison for taste, color, odor, and general acceptance were observed in jujube vinegar and commercial apple vinegar. The type of raw material and the conditions of the fermentation process have the greatest impact on the quality of the final vinegar the correlation between the color of the traditional vinegar samples and antioxidant properties indicates the presence of more phenolic compounds, which in the case of commercial apple vinegar indicates the presence of caramel in vinegar
Nazila Zeinali Namdar, Leila Roufegarinejad, Ainaz Alizadeh, Seid Mahdi Jafari Jafari, Narmela Asefi,
Volume 19, Issue 125 (July 2022)
Abstract

In this study, the effect of enzyme type (alcalase and pepsin) and process time (50-300 minutes) on the degree of hydrolysis and antioxidant indices including free radical scavenging of DPPH, ABTS, hydroxyl, reducing power, and chelating activity of Iron and copper ions were evaluated for navy bean protein (Phaseolus vulgari L.). Also, the composition of amino acids (hydrophobic and antioxidants types) and structural properties (FTIR) of primary protein and hydrolysates were investigated. The results showed that enzymatic hydrolysis improves antioxidant properties. Also, the composition of amino acids has a significant effect on antioxidant activities. On the other hand, the type of enzyme and the time of the hydrolysis process affected the degree of hydrolysis and the antioxidant activity of the hydrolysates. Thus, the highest percentage of free radicals scavenging of DPPH (82.4%), ABTS (58.3%), reducing power (0.97), hydroxyl radical scavenging (57.5%), and chelation of Fe (53.7%) and Cu ions (12.1%) were affected by the type of enzyme and process time. Among different treatments, the highest value of these indices (except copper ion chelating) was related to hydrolysates with alcalase. Structural properties of white bean protein were evaluated and enzymatic hydrolysis caused changes in the amide regions (I and II) as well as exposure to some hydrophobic-buried groups. The results of this study indicated the positive effect of enzymatic hydrolysis on the production of antioxidant hydrolysates that can be used in the food industry.
Abolfazl Bojmehrani, Bahareh Hajirostamloo, Mohsen Vazifedoost, Zohre Didar, Seid Mahdi Jafari Jafari,
Volume 19, Issue 125 (July 2022)
Abstract

Oxidation of lipids in food is one of the most important factors in food degradation during processing, storage and distribution through adverse effects on aroma, color, nutritional value and also the production of toxic compounds. In this regard, this study was conducted to investigate the antioxidant effects of free grape pomace extract and nanoliposomes containing it on some oxidation parameters of soybean oil. In this study, 5 concentrations of nanoliposomes containing grape pomace extract (50, 100, 200, 500 and 1000 ppm), one level (200 ppm) of synthetic antioxidant (BHT) and one concentration (500 ppm) of free grape pomace extract were used and tests such as Acidity, peroxide, thiobarbituric acid index, conjugate diene, oxidative stability and refractive index of oils were stored in a laboratory oven at 63 ° C for 7 days. The results showed that with increasing the concentration of nanoliposomes containing antioxidants of grape pomace extract up to 500 ppm, the increase in acidity, thiobarbituric acid index, peroxide, conjugated diene and refractive index was less intense, but at higher concentrations of nanoliposomes used in this oil, Increased more. On the other hand, it was found that with increasing storage time, the amount of acidity, thiobarbituric acid, conjugated diene increased, but the amount of peroxide and refractive index of oils increased until the fifth day and then decreased. The results also showed that the highest oxidative stability of oils (7.6 h) was related to the sample containing 500 ppm nanoliposomes containing antioxidant extract of grape pomace. Finally, it can be said that the use of nanoliposomes containing grape pomace antioxidant extract is a good alternative to synthetic antioxidants on the market.

Page 1 from 1