Showing 7 results for mizani
Volume 14, Issue 6 (11-2012)
Abstract
Volatile compounds generated from two types of polymeric laminated films, irradiated by gamma radiation at 8, 10 and 15 kGy, were investigated. Activated carbon was used as a dry food simulant to trace the migrating compounds by Gas Chromatography/Mass Spectroscopy (GC/MS). The resulting data showed that the Polyethylene Terephthalate (PET)/Polyethylene Terephthalate (PET)/Linear Low Density Polyethylene (LLDPE) film was more resistant to gamma radiation as compared to Biaxial Oriented Polypropylene (BOPP)/Cast Polypropylene (CPP) film. Toxic radiolysis products migrated through both laminated films at 8 and 15 kGy gamma irradiation. The toxic products originating from additives formulated in adhesive and in direct food contact layers may be considered as high risk against the safety of dry foodstuffs such as spices.
Volume 17, Issue 3 (5-2015)
Abstract
The aim of this study was to investigate the effect of the addition of commercial lipase in various forms on the acceleration of the ripening of UF-Feta cheese. Commercial lipase from Aspergillus niger was encapsulated by using silica composition based on Sol-Gel method. Lipase was then added to cheeses in three forms, namely, free lipase, encapsulated lipase, and encapsulated lipase with Arabic gum. Lipase was added to the retentate in the ratio of 4 g:100 kg. The effects of free lipase, encapsulated lipase, and encapsulated lipase with Arabic gum on lipolysis, quantity of free water, bounded water, and chemical compounds were studied during the 60 days of ripening. Based on FTIR analysis, encapsulated lipases were completely released from the capsules during the first 15 days of ripening period. The greatest amount of lipolysis was detected in free lipase samples, compared to encapsulated and encapsulated with Arabic gum treatments. Thermal analysis of all treatments indicated that lipolysis could affect the free and bounded water content by decreasing both of them from the 15th to 60th days of ripening. The amount of salt, moisture, and fat changed during the first 15 days of ripening significantly (P< 0.05). In comparison with free or encapsulated lipase, the encapsulated lipase with Arabic gum caused more changes in types of water and chemical compositions because the produced emulsions were uniform.
Volume 18, Issue 121 (March 2022)
Abstract
Recent epidemiological studies have indicated the anticancer activity of an isothiocyanate compound named sulforaphane that exists in cruciferous vegetables. Broccoli sprouts are popular because of containing far more anticancer, antioxidant, glucosinolate, and polyphenolic compounds than in mature broccoli. The main objective of this research was to produce a vegetable smoothie based on broccoli sprouts as a nutritious, health-enhancing snacking-drink. Broccoli sprouts were added at six different levels (0%, 2.5%, 5%, 7.5%, 10%, 12.5%, 15%) to a green smoothie made with carrots, apples, spinach, avocado, orange, lime, Stevia, and Gellan gum. Physicochemical, rheological, and sensory properties, along with levels of the bioactive compounds (Phenolic, antioxidant capacity, Chlorophyll), were studied during storage for 14 days at 5°C. The results showed that the addition of 15% broccoli sprout to the smoothie increased synergistically the phenolic compounds content and antioxidant activity by 38% and 24%, respectively. All of the treatments showed viscoelastic behavior. A pseudoplastic behavior with a flow index of less than 1. Sensory evaluation of the smoothie samples indicated the highest overall acceptance for smoothie samples containing 12.5% of broccoli sprout and using the higher levels negatively affected the sensory properties. As a result, a green smoothie containing 12.5% broccoli sprouts could be introduced as a health-promoting snacking-drink.
Volume 19, Issue 123 (May 2022)
Abstract
Kopeh cheese is one of the traditional Iranian cheeses. In this study, the effect of ripening time on its physicochemical properties was investigated during 187 days of ripening. The results showed that ripening index and pH increased significantly, while "salt in dry matter" decreased (p <0.05). The maximum delta tangent (TD) ranged from 0.35 to 0.4. The Differential Scanning Calorimeter (DSC) curve showed two exothermic peaks for cheese-extracted fat ripened on days 7, 37, 67, and 127; three exothermic peaks for the sample ripened on 97 days, while two exothermic and endothermic peaks for the sample ripened on 187 days, in the cooling phase. The results of principal component analysis (PCA) showed that PC1 and PC2 divided cheeses into four different groups, and PC3 identified only one group, including cheese day 127, with a high correlation with "moisture in the non-fat dry matter", "salt in dry matter," and "fat in dry matter". Also, they showed a significant correlation with TD (p<0.05). These chemicals had the most important impact on the physical properties of Kopeh cheese.
Volume 19, Issue 126 (August 2022)
Abstract
Cocoa milk is a popular milk-based drink, which its development can play a pivotal role in approaching the per capita dairy consumption in Iran. To sustain the product different stabilizers are used in the industry. The most common of which are carrageenan. Stabilizers are imported; therefore, they affect the finished product price.
The main objective of this study was to investigate the effect of stability of acetyl starch with Kapa and Utah carrageenan on pasteurized cacao milk in terms of the characteristics of milk cacao and rheology.
Initial experiments concentrating on physicochemical properties of samples which have different levels of starch, kappa, and carrageenan have been done. Initial tests of cacao milk including PH, acidity, and fatty dry matter measurements as well as sensory evaluation on all samples have been carried out. A preliminary analysis of stability and sedimentation was performed using centrifuge.
According to the results, 4 samples were selected with better sensory and physicochemical properties among 28 treatments and Rheological tests were performed on these specimens.
To better examining the results Hustler-Balkillian, ostwald and Bingham models were used. Herschel-Ballykleychr('39')s model has better adjustment with the results.
Finally, according to the results of rheology, a sample with a higher starch content was selected which contains 50% of starch in its stabilizing composition
Volume 19, Issue 130 (December 2022)
Abstract
The aim of this study is extraction of potato protein via incorporation of ultrafiltration with different diafiltration times (90, 285 and 480 min), and evaluation of physicochemical and functional properties of extracted protein. So, in terms of functional characteristics (solubility, water and oil absorption capacity, emulsifying activity and emulsion stability) the concentrated permeate and retentate proteins, have been compared with control sample. In retentate and control samples the solubility increases significantly (P˂0.5) with raising the pH from 3 to 7, inverse it decreased between the 7 to 9. In addition, it was found that the solubility of retentate proteins were significantly (P˂0.5) more than control and permeated proteins. Also, the water absorption capacity of retentate proteins (18.85 g Water/ g protein Retentate 480 min) were more than the other samples (2.54 g Water/ g protein Permeate 90 min). Whereas, oil absorption capacity was significantly (P˂0.5) depended on diafiltration time and process. In a way that, by increasing the time this parameter dropped in all of the samples. It was also found that, the oil absorption of retentate samples (59.09 g oil/ g protein Retentate 90 min) were significantly (P˂0.5) more than the permeate ones (32.13 g oil/ g protein Permeate 90 min). Emulsifying activity and solubility of retentate samples were significantly grew by addition of diafiltration time, while these indexes reduced in permeate samples. The thermal analysis of retentate sample (with 480 diafiltration time) indicated that, it had higher water absorption capacity than control.
Volume 20, Issue 134 (April 2023)
Abstract
Today, pasta is one of the most popular foods, and the addition of bran into its formulation provides the possibility of producing a healthy, high-fiber food product. As some micronutrients may become unavailable due to complex formation by phytic acid, which is present in bran, reducing the amount of this ingredient may eliminate this limiting factor and improve its applications in foods. The raw bran used in this study was first ground into two mesh sizes, 90 and 120 micrometers and then, processed by two stages of dry/humid thermal processes, accomplished in an autoclave and oven, at temperatures of 121°C and 150°C for 90 and 20 minutes, respectively. The bran sample mixed with the pasta flour in proportions of 2.5, 5, and 7.5(gr/100gr flour). The rheological characteristics of the mixed- flour pastes were analyzed by Mixolab test to determine the best formulation for the Sedani-type bran-enriched pasta. Van Soest and the high-performance liquid chromatography methods were used to evaluate the insoluble portion of fiber in acidic detergent and phytic acid, respectively. According to the results, two paste formulations containing 5 and 7.5% of the bran exhibited the best rheological properties. In conclusion, the pasta sample formulated with 5% of the processed bran showed the lowest cooking loss and the highest sensory scores compared to control and may be recommended as the best treatment.