Raheleh Mahjoub; Vahid Hakimzadeh; Esmaeil Atayesalehi; Jamshid Farmani
Abstract
Introduction: The solidification of edible oils via some techniques like hydrogenation is always accompanied by an increase in the amounts of saturated fatty acids (SFA) and trans fatty acids (TFA). Such fatty acids play a crucial role in cardiovascular diseases which put health of consumers at risk. ...
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Introduction: The solidification of edible oils via some techniques like hydrogenation is always accompanied by an increase in the amounts of saturated fatty acids (SFA) and trans fatty acids (TFA). Such fatty acids play a crucial role in cardiovascular diseases which put health of consumers at risk. Today, various techniques are applied to reduce the amounts of SFA and TFA in fatty-based products. These techniques are including the blending of some fats, esterification and recently oleogel system. In this study, some oleogel systems prepared by mixing monoacyleglycerol (MAG) and polyglycerol ester (PGE) and adding to a mixture of 20% palm stearin oil and 80% rapeseed oil to decrease saturation in shortening were studied. Materials & Methods: This research was conducted to investigate the structuring effect of mono-acilglycerol (MAG) and polyglycerol ester (PGE) to formulate some fatty-based product. For this purpose, various binary mixtures (VBM) of PGE:MAG were added to base oils ( 80% Canola Oil and 20% Palmestearin Oil ) at concentrations of 3, 6 and 9 (wt %) with ratios of 0:100, 20:80, 40:60, 60:40, 80:20, 100:0. Result and Discussion: The results showed that saturated fatty acid (SFA), slip melting point (SMP) and solid fat content (SFC) increased with an increase in the VBM of MAG. MAG did not affect peroxide value and the free fatty acids. Rancimat test presents contradictory results. The rheological analysis revealed that G", G', G* and tan δ of the base oil were increased to 105 Pa. With proper plasticity and low SFA, MAG-based fats can be applicable in the production of some fatty-based products like bakery margarine and all-purpose shortening.Due to the necessity of reduction in SFA content and TFA content in fatty-based products, researchers and producers have prompted to identify the applicable techniques for producing healthy fats. This study was set up in order to introduce the structured fats with low-SFA/TFA suitable in the formulation of shortenings and margarine.
Sima Shamsaei; Seyed Mohammad Ali Razavi; Bahareh Emadzadeh; Esmaeil Atayesalehi
Abstract
Introduction: An emulsion is made of dispersed particles through the continuous phase, while not dissolving happens between two phases. Mayonnaise is oil-in- water emulsion (James and Dakin, 1962), as one of the most sauces used in the world. It has a mild odor and taste, creamy to pale yellow color ...
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Introduction: An emulsion is made of dispersed particles through the continuous phase, while not dissolving happens between two phases. Mayonnaise is oil-in- water emulsion (James and Dakin, 1962), as one of the most sauces used in the world. It has a mild odor and taste, creamy to pale yellow color and a pH in the range of 3.6- 4.0, which does not exceed 4.1 (Iranian National Standard, No 2454). Emulsion products are naturally instable. Different factors such as temperature, particles size, stirring, mechanical movements, constituents’ concentration, presence or absence of stabilizers and thickeners may affect the emulsion stability (David, 1999). Ocimum basilicum L., known as basil (or ‘‘Reyhan” in Iran), is a common herb plant grown in Iran. Soaking in water, basil seeds become gelatinous. The high mucilage content of basil seeds can make it a novel source of edible gum (Razavi et al., 2008). The objective of this paper was to investigate the effect of basil seed gum as well as xanthan as fat replacers on some physical and rheological properties of low fat mayonnaise. Materials and methods: Emulsion stability determination: Mayonnaise samples were centrifuged at 5000 rpm for 30 minutes. Emulsion stability (ES) was then determined using the following relation (Worrasinchai S et al., 2006): Stability index= (Total volume/ Volume of emulsion remaining)100. Particle size measurement: Particle size distribution of low-fat mayonnaise samples was determined using laser light diffraction technique (Fritsch Analysette 22, Germany). Rheological measurements: A rotational viscometer (Visco 88, Malvern, UK) equipped with a thermal circulator was used to measure the steady shear rheological properties of samples at the shear range of 14-300 s-1 and constant temperature of 25 oC. Power law, Bingham, Casson, and Herschel-Bulkley models were fitted on the experimental data and the rheological parameters of these models were determined using Slidewrite plus-bar Graph software (1983, Advanced Graphics Software, Inc, USA). Image processing: A scanner was used to capture the samples’ image and the scanner resolution was set to 300 dpi. 7g sample was placed onto a plate and then 152×210 Pixel parts was cut from the obtained image. All images were stored in JPEG format for further analysis. The Clemex image processing software (Clemex Vision Professional, PE4, Canada) was used to determine the color parameters (L*, a* and b*). Results and Discussion: Steady shear flow behavior: The results showed that all samples are classified rheologically as non-Newtonian shear thinning fluids. According to R2 values, Power law was considered as the best rheological model to describe the flow behavior of samples. The maximum and the minimum consistency coefficients of Power law model were observed for the formulation containing 0.75% xanthan gum and 0.45% basil seed gum, respectively. In this study, the apparent viscosity of mayonnaise (in shear rate 42 s-1) raised with increasing gum concentration that this increase in samples 4 and 5 were not significant (P>0.01). The highest apparent viscosity was observed in sample 3 that was prepared with a concentration 0.75% of xanthan gum, while the lowest viscosity was related to sample 4 that was contained of 0.45% basil seed gum. With increasing gum concentration, Bingham viscosity of the samples increased, but this increase in the samples (1, 7, 8) and (2, 6, 9) was not significant (P> 0.01). Yield stress values of Herschel-Bulkley (τH), Bingham (τB) and Casson (τC) models raised with the increasing of gum concentration. Highest yield stress value was related to mayonnaise containing 0.45% xanthan gum and the lowest yield stress value related to mayonnaise prepared with 0.45% basil seed gum. Particle size distribution: Particle size distribution of mayonnaise at concentration of 0.6 % xanthan gum, basil seed gum and mixture of xanthan- basil seed gum had mono-modal particle size distribution. Emulsion stability: Among samples, formulations of 1, 2, 3, 8, and 9 were quite stable and there was no instability (two-phase state). Higher stability in emulsions containing xanthan gum was probably due to higher viscosity of this gum compared to basil seed gum. Color: The best color was observed in sample 6. In this study, with increasing concentration of gum in three samples (1, 2, 3), the amount of L* decreased, it means that the brightness of the product was reduced while in samples containing a mixture of gums (xanthan- basil seed gum), increasing the gum concentration resulted in an increase in L* parameter.
Amir abbas Omidfar; Esmaeil Atayesalehi; Zahra Sheikholeslami
Abstract
Introduction: Low quality and short shelf-life are the most important reasons for bread waste. Statistics show that each Iranian person consumes about 150 kg bread annually, but the low quality of bread and public discontent, would resultin 30 percent waste of traditional breads. Previously barley malt ...
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Introduction: Low quality and short shelf-life are the most important reasons for bread waste. Statistics show that each Iranian person consumes about 150 kg bread annually, but the low quality of bread and public discontent, would resultin 30 percent waste of traditional breads. Previously barley malt was used as an additive to improve the quality and shelf life of bread (including Barbari bread). The most common type of the malt used in the world is barley malt. This is because of the utilization of most of the malt product in the world, including to produce beverages based on malt, particularly alcoholic and non-alcoholic onesand considering that the malt made from barley grains has the best quality among the other cereals to produce these products.Therefore, discussion on other malted cereals would be find less in the literature especially corn malt (which has not a good quality to produce malted beverages). On the other hand, corn is the main cereal widely consumed in the world after wheat and rice. The purpose of this study was to produce Barbaribread usingcorn malt (powder or extract) as an additive to increase shelf-life, volume and softness, as well asimprove the sensory characteristics (staling, total appearance, softness, texture, brain color, crust color, crust appearance, flavor and odor). Materials and methods: For this purpose, bakery flour with 85% extraction rate, Dent corn (Zea mays var. Indentata), Saccharomyces cerevisiae as an active dry yeast, malt extract or powder and other additives, used in the formulation of Barbari bread. To evaluate the sensory characteristics, the bread samples were analyzed by 15 trained referee. The results were based on a factorial arrangement with two factors completely randomized design that the first factor is type of corn malt (powder or extract) and the second one is amount of corn malt (in four levels of 0, 0.5, 1.0 and 1.5 percent) was evaluated. Results & Discussion: The resultsshowed that the treatment with 1.5 percent extract corn malthas the highestspecific volume(with an average of 4.5) and thetreatment with 1.5 percent powderhas the lowestspecific volume(with an average of 3.67). And just the treatments with 1 and 1.5% malt extract in compared with the control sample showed significance differences (P
Esmaeil Atayesalehi; Seyedeh Tahereh Nasiri Takami; Reza Esmaeilzadeh kenari
Abstract
Compounds derived from lipid oxidation endangering human health and lead to cardiovascular disease and cancer. The addition of antioxidants is effective in retarding the oxidation of lipids and lipid containing foods. Due to the toxicological effects of synthetic antioxidants, Decrease their use and ...
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Compounds derived from lipid oxidation endangering human health and lead to cardiovascular disease and cancer. The addition of antioxidants is effective in retarding the oxidation of lipids and lipid containing foods. Due to the toxicological effects of synthetic antioxidants, Decrease their use and replacing them with natural antioxidants. This study investigates antioxidant effect of Pimpinella methanolic extract (PME) on inhibition of lipid oxidation in canola oil (CO) in comparison to the canola oil stabilized Tert-butyl hydroquinone (TBHQ). PME was added at 400 and 800 ppm to CO. Color Index (CI), Conjugated diene value (CDV), peroxide value (PV), Acid Value (AV), were determined during 60 days of storage. Different oxidation parameters revealed that methanolic extract of Pimppinella affinisLedeb at concentration of 800ppm was more effective than 400ppm. Results revealed Pimpinella to be a potent antioxidant for stabilization of canola oil. As expected with increasing of the storage time, the oxidative stability of canola oil decreased.
Mehdi Jalali; Esmaeil Atayesalehi; Mohammad Hossein Hadad Khodaparast
Abstract
Of a large amount of date palms cultivated and harvested in Iran, only about 11 – 12 annual percent is used in food processing and packaging industries. Due to the poorq uality of produced dates, it is regarded as waste and is mainly used as feed stocks. Thus, through producing syrup and liquid sugar ...
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Of a large amount of date palms cultivated and harvested in Iran, only about 11 – 12 annual percent is used in food processing and packaging industries. Due to the poorq uality of produced dates, it is regarded as waste and is mainly used as feed stocks. Thus, through producing syrup and liquid sugar from date palm of low quality could be regarded as a new opportunity to convert waste dates to a higher value product in order to reduce imports of similar products and also to export it in large quantities. In the present study, the face-center central composite design of response surface methodology was used to investigate the influence of temperature (60-80 °C), pH (4-7), time (1-5 h) and water-to-date pulp ratio (1:3-1:5) on yield and absorbance of Juice extraction from grade II date of the Kaluteh variety and its optimization. The results revealed that all the investigated independent variables have significant influence on the process, but the effect of time was not significant on the absorbance. Also, the main influencing parameter on the extraction process of palm was observed to be the water-to-date pulp ratio. The results showed that the extraction yield increased at elevated temperatures, higher mixing ratios, longer times and lower pH, whereas increasing temperature and decreasing pH had a negative impact on clarity of syrup. The optimum conditions obtained for the extraction process were temperature of 77.45 °C, time of 5 h, mixing ratio of 1:4 and pH= 4. At the optimum conditions, the yield and absorbance were found to be 62.5 % and 0.28, respectively.
