Mohammad Reza Toorani; Reza Farhoosh; Mohammad Taghi Golmakani; Ali Sharif
Abstract
Introduction: Lipid oxidation is one of the most important factors affecting the loss of quality or the deterioration of edible oils. This reaction is accompanied by the production of harmful compounds that may threaten consumer’s health. Several parameters affect the severity of the oxidation ...
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Introduction: Lipid oxidation is one of the most important factors affecting the loss of quality or the deterioration of edible oils. This reaction is accompanied by the production of harmful compounds that may threaten consumer’s health. Several parameters affect the severity of the oxidation reaction, among them temperature is one of the most important parameter to consider. Lipid oxidation increase significantly with the increase of temperature, which drastically reduces the length of the shelf life of the oils. Numerous methods have been used to postpone the oxidation of oils that one of the most useful methods is the addition of antioxidants. Nowadays, natural antioxidants have been located in the hotspot of attention from safety and sensory characteristics point of view. Sesamol as a valuable natural antioxidant may help to provide healthy edible oils. The determination of thermal kinetic data and the evaluation of thermodynamic indices have long been used to the better identify the mechanisms and the events caused by temperature elevation. Examining the temperature and time variables together and merging these components could provide valuable information about the environmental effects of foodstuffs. These parameters are particularly important for edible oils. Hence, the kinetic-thermal information of the oils oxidation in the presence of sesamol may provide the valuable assistance in explaining the storage conditions of various edible oils in the presence of this antioxidant. Materials and methods: The sesamol's ability to quench free radicals was determined by DPPH test and at 517 nm. The oil purification process was performed by adsorption column chromatography in order to eliminate minor components that may be interfere with the oxidation reaction. The evaluation of the accelerated oxidation process in presence of sesamol was carried out in a dry oven and through monitoring the accumulation of hydroperoxides (peroxide value) over time at 60, 80 and 100 °C. The peroxide value was measured spectrophotometrically at 500 nm. The induction period of oils oxidation was determined through two lines fitted on initiation and propagation steps of the oxidation curve. The rate constants of the oils oxidation and sesamol consumption, the peroxide value corresponding to the length of induction period (PVIP), the minimum sesamol concentration to demonstrate the antioxidant activity and the oxidative stability time of lipid systems at ambient temperature were also determined by oxidation kinetic data. Results and discussions: The results of inhibitory test showed that the amount of sesamol required to inhibit 50 percent of the DPPH radicals is equal to 1 mM. The induction period of olive oil has reached to over 520 h in presence of 0.01% sesamol at 60 °C, whereas sesame and canola oils were placed in the subsequent positions with nearly 330 and 325 h, respectively. The average extent of PVIP (all sesamol concentrations) for two lipid systems i.e. sesame and canola oils was close to each other and drastically higher from olive oil. This delocalization of the numbers suggests that the PVIP is independent of the antioxidant concentration available and is affected by the fatty acids structure of oils. The effect of temperature elevation on the rate constant of oxidation for different oils did not follow the same pattern, so that the slope of increase of the rate constant for olive oil was very mild than to the other two oils. The results showed that the increase in temperature has markedly increased the rate of sesamol consumption, so that unsaturated lipid systems have undergone significant changes in this regard. Increasing the temperature increased the minimum concentration required for the antioxidant activity of sesamol. This pattern was linear for olive oil and hyperbolic for sesame and canola oils.
Marzieh Moeenfard; Paniz Khaloo Kermani; Shima Jaldani; Ali Sharif
Abstract
Introduction: Coffee is the most important and popular beverage in the world. The main differences between coffee and other beverages like tea is the variety of applied brewing techniques. Coffee is a complex chemical mixture of compounds including, caffeine, as a natural alkaloid. Besides its beneficial ...
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Introduction: Coffee is the most important and popular beverage in the world. The main differences between coffee and other beverages like tea is the variety of applied brewing techniques. Coffee is a complex chemical mixture of compounds including, caffeine, as a natural alkaloid. Besides its beneficial effect including enhancement in mental activity and alertness as well as improving the cognitive functioning, caffeine indicated adverse effects such as headache and anxiety when it is consumed in higher quantity. In terms of chemical extraction, it can be also considered as an interference when analyzing other pollutants, therefore, its removal from extract is of great interest. Therefore, the present study was designated to investigate the caffeine content of 18 various coffee-related products. Furthermore, the effect of two extraction techniques (QuEChERS and conventional) on caffeine removal from coffee extract was investigated. Materials and Methods: Coffee brews including classical (boiled, French, moka and filtered coffees) and commercial brews (various types of espresso as well as instant and iced coffees) were prepared using Robusta, Arabica coffee or commercial powders. In conventional extraction approach, a 2.5 mL of coffee sample was treated with 0.1 mL each of Carrez solutions I and II to clarify the sample. The total volume was brought to 50 mL by the addition of 10% methanol (v/v). After centrifugation, the supernatant was filtered and analyzed using high-performance liquid chromatography coupled with a diode array detector (HPLC-DAD) at 273 nm. In QuECHERS approach, the effect of extraction solvent (acetonitrile and ethyl acetate) and sorbents (primary and secondary amines and, octadecyl silane) on caffeine removal was investigated and was compared to conventional approach as reference method. The extraction and clean-up were accomplished by two types of solvents and sorbents in the presence of sodium chloride and magnesium sulfate. Finally, caffeine was determined using HPLC-DAD at 273 nm. Results and Discussion: According to the results, the two coffee varieties (Arabica and Robusta) were clearly separated by their caffeine contents as Robusta presented higher values in all classical brews. Among the classical brewing techniques, the coffee with the highest content of caffeine was moka brewed from roasted Robusta coffee, with a mean value of 1044 ± 26 mg/L. The caffeine content was also determined per serving (cup size) to determine the actual content received by consumers. Accordingly, among traditional brews the most caffeine-rich coffee was espresso type pod coffee, with a mean value of 1371 ± 16 mg/L, equivalent to 56 ± 0.6 mg/40 mL of serving size. The lowest mean caffeine content (13.4 mg / 240 mL) was found in iced coffee. With regards to caffeine extraction, with recovery of 101%, the conventional method was the most efficient approach for caffeine determination. Caffeine significantly reduced (around 20% compare to conventional approach) when QuEChERS was used as extraction technique which could be valuable for analysis of pesticides, which are usually present in small quantities in food samples like coffee. In general, the use of acetonitrile as well as the simultaneous application of PSA and C18 resulted in a significant decrease in caffeine content of Robusta coffee extract.Here, different coffee brews were assessed and compared for their caffeine content (mg/mL and mg/serving). Technical differences like coffee varieties, coffee/water ratio or method of brewing (pressurized, fusion, filtering, etc) led to coffee brews with different caffeine profiles. Interestingly, despite the high concentration of caffeine in espresso types brews, they provided moderate coffee in terms of caffeine content per cup. On the other hand, classical methods in particular boiled, French and filtered Robusta coffee were rich in terms of caffeine per cup. When studying caffeine extraction, the efficiency of conventional method was significantly superior to QuEChERS approach as caffeine significantly reduced when QuEChERS was used as extraction method.
Fatemeh Habibi Nodeh; Reza Farhoosh; Ali Sharif
Abstract
Introduction: Frying is one of the oldest and popular preparation techniques broadly used at home and food industry. High temperatures plus the presence of air as well as the water from the food being fried cause many destructive reactions. Therefore, thermal stability and performance of oil during frying ...
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Introduction: Frying is one of the oldest and popular preparation techniques broadly used at home and food industry. High temperatures plus the presence of air as well as the water from the food being fried cause many destructive reactions. Therefore, thermal stability and performance of oil during frying is considered as one of the important criteria in the selection of frying oil. In this regard, balanced chemical composition, presents it as a valuable option for frying purposes. Studies show lipid autoxidation considered as the most important deteriorative reaction in the olive oil. This reaction leads to the formation of a series of primary and secondary oxidation products. Hydroperoxides are the primary oxidation products of lipid oxidation. Carbonyl value (CV) does measure secondary decomposition products are more stable than peroxides and the CV seems to be a good index of oxidative changes in lipids. Therefore, the determination of carbonyl compounds in frying oils is very important for evaluating the quality of frying fats and oils. Several studies have been carried out on the oxidative stability of edible oil during frying. Rancimat test has also been considered among the accelerated methods of lipid oxidation measurement due to ease of use and reproducibility. However, although estimate of oxidative stability of edible oil according to accelerated methods, is used widely but there is always worries about accordance the results of such tests with the results found under real frying conditions and Presence of food. Therefore, necessity of simultaneous study oxidative stability is essential in order to justify and extension of result together during heating and frying.
Materials and methods: Six refined olive oil samples of different brands in 1 lit glass bottles were purchased from local shops and were stored at 4 ºC for further analysis. Fatty acid methyl ester (FAME) standards, and all chemicals and solvents used in this study were of analytical reagent grade and supplied by Merck and Sigma Chemical Companies. The ratio between monounsaturated and polyunsaturated fatty acids (M/P) was determined by gas–liquid chromatography. The spectrophotometric method was used to determine the PV. The AV was determined according to the AOCS. The TT content was determined according to the colorimetric method. The TP content was determined spectrophotometrically using Folin–Ciocalteau’s reagent. The CV of the oils was measured using 2-propanol and 2,4-decadienal as solvent and standard, respectively. A Metrohm Rancimat model 743 (Herisau, Switzerland) was used to measure the OSI and IPCV of olive oil samples. Frying process was performed in bench- top deep- fryer at 180ºC. ANOVA and regression analyses were performed according to the MATLAB and Excel software. Significant differences between means were determined by Duncan’s multiple range tests.
Results and discussion: There was good correlation between the OSI and induction period (IPcv) at the temperature range studied with a high determination coefficient (R2>0.99) in the Rancimat test. Generally, the results of the present study showed that the Rancimat method at 110 ºC correlated well with stability under frying condition and this correlation decreased as temperature increased in the Rancimat test. These observations can be explained by the fact that steps or pathway of chemical reactions that take place at low and high temperatures are different. Thus, choosing the right levels of operational parameters in the Rancimat method can produce the least possible difference between frying and the OSI test.
Azadeh Mardani Ghahfarokhi; Reza Farhoosh; Ali Sharif
Abstract
Introduction: Hydroxybenzoic acids are a large family of phenolic acids capable of inhibiting one of the most destructive reactions called lipid oxidation. Their antioxidant activities are markedly influenced by the number and position of phenolic OH groups. Increasing the number of electron-donating ...
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Introduction: Hydroxybenzoic acids are a large family of phenolic acids capable of inhibiting one of the most destructive reactions called lipid oxidation. Their antioxidant activities are markedly influenced by the number and position of phenolic OH groups. Increasing the number of electron-donating groups in the molecule and their placement at the ortho and/or para positions of the phenolic ring, could lead to the increased ability of H atom abstraction or electron donating capacity. Gentisic (3,5-dihydroxybenzoic acid) and Alpha-resoecylic (2,5-dihydroxybenzoic acid) acids are dihydroxybenzoic acids wildly dispersed in the plant tissues with some valuable biological and pharmacological properties for human health. These compounds are different in structure and position of hydroxyl groups in phenolic ring, that may had a strong influence on their antioxidant properties. In addition of structural property, environmental interference can play an important role in the antioxidant potency. Antioxidants are found to behave differently when used in different media.
Materials and methods: Partition coefficient (log P) of Gentisic acid and Alpha-resorcylic acid was measured between 1-octanol and acetate buffers. Antiradical and antioxidant activity of compounds was investigated in different medium (solvent system, purified bulk olive and soybean oils and their O/W emulsions). DPPH radical scavenging activity of gentisic acid and alpha-resorcylic acid was measured in the methanolic solvent. Progress of lipid oxidation in olive oil and soybean oil containing 200 ppm of the antioxidants at 80 oC was followed by monitoring the changes in peroxide value (PV). PV was measured spectrophotometrically at 500 nm using a UV– Vis instrument. Oxygen depletion in emulsion systems in the absence and present of the antioxidant (200 ppm) was measured using a YSI Model 5300A biological oxygen monitor at 37oC. The effectiveness of the antioxidants in bulk oils and emulsions was estimated on the basis of the induction period (IP).
Results and discussion: The obtained results indicated that the effectiveness of the Gentisic and - resorcylic acids in free radicals scavenging, was greatly affected by molecular structure of these antioxidants and environmental conditions.
Ortho position of hydroxyl group with respect to the carboxyl group in Gentisic acid, caused higher antiradical potency of Gentisic acid than α-resorcylic acid, with meta-structure, in different used mediums.
In addition, it was found that the environment plays an important role in the free radical scavenging activity of phenolic compounds. Gentisic acid with more hydrophilic structure showed better antioxidant activity in bulk oil hydrophobic systems, than emulsion systems, while -resorcylic acid with less hydrophilic structure showed better activity in O/W emulsions. Both antioxidants showed low antioxidant performance in solvent system. The polar medium of the methanol used in DPPH assay, with enhanced intermolecular hydrogen bonds, decreased the radical scavenging potency of antioxidants.
Najmeh Molaahmadibahraseman; Reza Farhoosh; Ali Sharif
Abstract
Introduction: Medical benefits of Omega 3 fatty acids have appealeda lot of research to be done on of fish oil. Among marine fish, kilka has the most industrial application. Kilka oil contains significant amount of omega-3 fatty acids. In this study, physiochemical properties, fatty acid composition ...
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Introduction: Medical benefits of Omega 3 fatty acids have appealeda lot of research to be done on of fish oil. Among marine fish, kilka has the most industrial application. Kilka oil contains significant amount of omega-3 fatty acids. In this study, physiochemical properties, fatty acid composition and stabilization of kilka oil were investigated. p- hydroxy benzoic asid, its methyl ester and alpha-tocopherol as control were compared to each other.Materials and Methods: Crude Kilka fish oil was supplied by Khazarcompany (Babolsar, Iran). All chemicals and solvents used in this study were of analytical reagent grade and purchased from Merck (Darmstadt, Germany) and Sigma–Aldrich (St. Louis, MO). 200 ppm of the mentioned antioxidants was added to the purified oil and kinetic regime of oxidation at temperatures of 35, 45 and 55°C was prepared. After monitoring theoxidation over time using peroxide test, graph of peroxide changes over time was plotted and induction period and kinetic parameters (F, ORR and A) were calculated. In order to compare the performance of antioxidants in oil and water, 10% emulsion of Kilka oil-in-water was prepared and 200 ppm of antioxidant was added to it and its oxidation process was monitored at 55°C.Results and Discussion: Results showed that the fatty acid composition of this oil contains a variety of unsaturated fatty acids, saturated and polyunsaturated (mainly linoleic, eicosapentaenoic and docosahexaenoic acids). Temperature had significant effect on oxidation. p-hydroxymethylbenzoate, a little more than p-hydroxybenzoic asid, could increase oxidative stability of oil. Alpha-tocopherol had better performance as compared with other antioxidants. Performance of methylp-hydroxybenzoatewas better in emulsion than oil. In general, the emulsifier and emulsion preparation as compared with antioxidant had a more prominent role in the oxidative stability of Kilka oil.
Najmeh Molaahmadibahraseman; Reza Farhoosh; Saeid Johny; Ali Sharif
Abstract
Introduction: Medical benefits of omega-3 fatty acids have led to a lot of research on fish oil. Among marine fish, Kilka has the highest industrial applications. Kilka oil contains significant amounts of omega-3 fatty acids. In the present study, oxidative stability of Kilka fish oil based on the Schaal ...
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Introduction: Medical benefits of omega-3 fatty acids have led to a lot of research on fish oil. Among marine fish, Kilka has the highest industrial applications. Kilka oil contains significant amounts of omega-3 fatty acids. In the present study, oxidative stability of Kilka fish oil based on the Schaal oven test and the use of two phenolic acid derivatives (syringic and vanillic acids) was investigated.Materials and methods: Crude Kilka fish oil was supplied by Khazar company (Babolsar, Iran). All chemicals and solvents used in this study were of analytical reagent grade and purchased from Merck (Darmstadt, Germany) and Sigma–Aldrich (St. Louis, MO). Free radical scavenging activities of phenolic compounds was measured by reading the absorbance of methanolic solutions of the antioxidants containing 1,1-diphenyl-2-picrylhdrazyl (DPPH)at 517 nm. The partition coefficient (log P) of the antioxidants was measured in terms of the maximal UV absorbance of aqueous (0.3 mM) and 50:50 aqueous/acetate buffer (0.1M, pH =5.5) solutions. In order to study the antioxidant activity in lipid systems, peroxide value of the chromatographically purified Kilka fish oil as well as its 10% oil-in-water emulsion containing 200 mg/kg of antioxidants was monitored at 55 °C. Results and discussion: Syringic acid with two methoxy groups showed higher scavenging activity (IC50) than vanillic acid with one methoxy group (54.2 vs. 418.2). Radical scavenging activity in phenolic acids had direct relationship with the type and number of electron donor groups on phenolic ring. Peroxide values changed exponentially. Despite the relatively high polarity (Log P = – 0.65) and high scavenging activity, the performance of syringic acid in Kilkafish oil was degraded as affected by inter-molecular interactions and was not in accordance with the "polar paradox" hypothesis. Antioxidant activity of syringic acid in emulsion increased significantly as compared with oil and it was similar to α-tocopherol. It was concluded that the type of emulsifier and also the way of emulsion preparation as compared with antioxidant had a more prominent role in the oxidative stability of Kilka fish oil.Introduction: Medical benefits of omega-3 fatty acids have led to a lot of research on fish oil. Among marine fish, Kilka has the highest industrial applications. Kilka oil contains significant amounts of omega-3 fatty acids. In the present study, oxidative stability of Kilka fish oil based on the Schaal oven test and the use of two phenolic acid derivatives (syringic and vanillic acids) was investigated.Materials and methods: Crude Kilka fish oil was supplied by Khazar company (Babolsar, Iran). All chemicals and solvents used in this study were of analytical reagent grade and purchased from Merck (Darmstadt, Germany) and Sigma–Aldrich (St. Louis, MO). Free radical scavenging activities of phenolic compounds was measured by reading the absorbance of methanolic solutions of the antioxidants containing 1,1-diphenyl-2-picrylhdrazyl (DPPH)at 517 nm. The partition coefficient (log P) of the antioxidants was measured in terms of the maximal UV absorbance of aqueous (0.3 mM) and 50:50 aqueous/acetate buffer (0.1M, pH =5.5) solutions. In order to study the antioxidant activity in lipid systems, peroxide value of the chromatographically purified Kilka fish oil as well as its 10% oil-in-water emulsion containing 200 mg/kg of antioxidants was monitored at 55 °C. Results and discussion: Syringic acid with two methoxy groups showed higher scavenging activity (IC50) than vanillic acid with one methoxy group (54.2 vs. 418.2). Radical scavenging activity in phenolic acids had direct relationship with the type and number of electron donor groups on phenolic ring. Peroxide values changed exponentially. Despite the relatively high polarity (Log P = – 0.65) and high scavenging activity, the performance of syringic acid in Kilkafish oil was degraded as affected by inter-molecular interactions and was not in accordance with the "polar paradox" hypothesis. Antioxidant activity of syringic acid in emulsion increased significantly as compared with oil and it was similar to α-tocopherol. It was concluded that the type of emulsifier and also the way of emulsion preparation as compared with antioxidant had a more prominent role in the oxidative stability of Kilka fish oil.
Samaneh Pazhouhanmehr; Reza Farhoosh; Reza Esmaeilzadeh kenari; Ali Sharif
Abstract
Introduction: Common Kilka (Clupeonella cultriventris caspia) is one of the most abundant and industrial fish in the Caspian Sea located in the north of Iran, and also the best source of long-chain polyunsaturated fatty acids, especially EPA and DHA [Fazli et al., 2009, Connor, 2000]. Due to high level ...
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Introduction: Common Kilka (Clupeonella cultriventris caspia) is one of the most abundant and industrial fish in the Caspian Sea located in the north of Iran, and also the best source of long-chain polyunsaturated fatty acids, especially EPA and DHA [Fazli et al., 2009, Connor, 2000]. Due to high level of the ω3 : ω6 ratio and polyene index, the common Kilka oil is expected to be highly susceptible to oxidation [Pirestani et al., 2010]. The interesting antioxidative characteristics of the oils and unsaponifiable matter (USM) extracted from the kernel and hull of bene fruit (Pistacia atlantica subsp. Mutica) attracted our attention to use them as natural alternatives for stabilizing the common Kilka oil and compare with BHT and α-tocopherol [Farhoosh et al., 2012]. Materials and method:The ripe bene fruits were collected from the fields of Islamabad in the Ilam province. After drying and also grounding to powder, the oils from the kernel (BKO) and the hull (BUO) of bene were extracted with n-hexane (1:4 w/v). Moreover, the USM content of the kernel (UKO) and hull (BHO) oils of bene were determined by the method described by Lozano et al, 1993. Chemical compositions of the bene oils’ unsaponifiable matter were determined by a thin-layer chromatography [Lercker and Rodriguez-Estrada, 2000]. Crude Kilka oil was purified by a multilayer column chromatography to eliminate the majority of pro-oxidant and antioxidant compounds normally present in it. The purified Kilka oil (PKO) was blended separately with 1 and 2% (w/w) of the antioxidative oils (BKO and BHO), 1 and 1.5% (w/w) of the oils’ unsaponifiable matter (UKO and UHO), and 100 mg/kg α-tocopherol and BHT and then exposed to the following stability test. Fatty acid composition of the oil samples was determined by gas-liquid chromatography [Sharina and Jumat, 2006]. The iodine value (IV) was measured according to the AOAC Official Method 920.158 [AOAC, 2005]. A colorimetric method was used to determine total tocopherols (TT) content [Wong et al., 1988]. Total phenolics (TP) content was spectrophotometrically determined using Folin–Ciocalteau’s reagent [Capannesi et al., 2000]. A Metrohm Rancimat model 743 (Herisau, Switzerland) was used for the oil/oxidative stability index (OSI) measurement in airflow rate of 20 L/h. The temperatures in measuring of the OSI were 60 °C for the PKO, OSI60, and 120 °C for the BHO and BKO, OSI120 [Farhoosh et al., 2008a; Mendez et al., 1996]. The analysis of variance (ANOVA) was carried out according to MStatC and SlideWrite software. Significant differences between means were determined by Duncan’s multiple range tests; p values less than 0.05 were considered statistically significant.Results and Discussion: The initial quality parameters of the PKO, BHO and BKO are shown in Table 1. The PKO was mainly constituted of MUFA, followed by the SFA and PUFA, and there was no measurable contents of TP, TT and USM fractions in it. The PKO showed a PUFA/SFA ratio higher than the minimum value recommended by the UK Department of Health (0.73 vs. 0.45) [HMSO. UK., 1994]. The ω3/ω6 ratio of the PKO was relatively similar to that of Indian mackerel (Rastrelliger kanagurta) (1.60 and 1.67, respectively) (Table 1) [Osman, Suriah, & Law, 2001]. The IV, as an indicator of the oil unsaturation and resistance to oxidation, for the PKO (114.99) was much lower than sardine (156.2) and salmon (165.8) oils [Frankel, 1998; Endo, Tagiri-Endo, & Kimura, 2005].As can be seen in Table 1, the BKO had higher contents of the USM, tocopherols and phenolic compounds than the BHO. The valuable effects of minor components especially polyphenols and tocopherols of the BHO and BKO on the oxidative stability of vegetable oils have been shown in the previous studies [Farhoosh et al., 2012]. The differences in the fatty acid composition and the amounts of minor components led to the greater OSI120 of the BKO than the BHO (9.46 vs. 7.91 h).The major constituents of the UHO and UKO were tocopherols and tocotrienols (Table 2). These compounds, which are particularly important functional constituents of the USM of vegetable oils, have nutritional importance for human health and render antioxidative properties [Lercker and Rodriguez-Estrada, 2000]. The OSI60 values of the PKO as affected by the antioxidative compounds are presented in Fig 1. As shown in Fig. 1, the OSI60 of the PKO (1.66 h) significantly increased in presence of the antioxidants added. Moreover, the highest significant stabilizing effect belonged to the UKO 1.5%, so that it was able to increase significantly the OSI60 up to 8.12 fold (OSI60, 13.48 h) (p < 0.05). Previous findings have demonstrated antioxidant activities of the constituents of the UKO and UHO in vegetable oils. In addition, it has been reported that the fraction of tocopherols and tocotrienols, and terpenoid compounds, particularly triterpenic dialcohols and 4,4'-dimethylsterols, possess antioxidative effects, in overall, better than those of other fractions examined [Farhoosh et al., 2008; Sharif et al., 2009]. Due to the higher amounts of these active fractions (Table 2), the UKO showed higher antioxidative effect on the PKO stability.
Nasser Sedaghat; Maryam Rastegari; Sara Khoshnoudi; Ali Sharif
Abstract
Introduction: Self-heating packaging (SHP) is an active packaging with the ability to heat food contents without external heat sources or power. Packets typically use an exothermic chemical reaction and then woul be useful for military operations, natural disasters, or whenever conventional cooking is ...
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Introduction: Self-heating packaging (SHP) is an active packaging with the ability to heat food contents without external heat sources or power. Packets typically use an exothermic chemical reaction and then woul be useful for military operations, natural disasters, or whenever conventional cooking is not available. These packages are often used to prepare main courses such as meat dishes, which are more palatable when hot.The system consists of three compartments that are separated within the can: the first is the packaged food item; the second, exothermic chemical material(such as calcium hydroxide); and in the third, water. Once the calcium hydroxide is dissolved within the water, it generates, in just 3 minutes, a large amount of heat (up to 60 degrees Celsius), which heats the food item that is located in the first compartment of the can and allows for it to remain hot for up to 20 minutes.For consumption,consumer must remove a seal on the base of the can to reveal the activation button. Pressing the button activates the heater. After 2-3 minutes, the contents of the can must be lightly shaken to ensure contents are at an even temperature. Setting the can upright, the consumer opens the package and enjoys a hot food or beverage.The present study would focuse on finding the new exothermic chemical materials for reducing cost or producing upper temperature.Therefore, the main objectives of this study were to determine the effect of type and amount of heat-producing compositions on heat-produced and temperature profiles of self heating cans.Material and methods: In this study,the designed self-heating canswere consisted of twoseparated compartments within the can.The first section of can was used for putting of food and the second section was used for storage of exothermic chemical materials. A misture of 6 exothermic chemical materials alkali-acidic, (Sodium hydroxide+citricacid ,Sodiumhydroxide+tartaric acid , potassium hydroxide +citric acid, potassium hydroxide +tartaric acid, Calcium oxide+citricacid and Calcium oxide+tartaric acid) was selected. alkalian-acidic composition was mixed in the ratio 1:1.5 and mixture weighing 150, 200 and 250 g were used in this investigation and placed in the free space between cans. For added degree of heat insulation using of glass wool as label outer of cans. Cans wall andcanned food (canned beans and eggplant caviar) temperature were investigated to determine the best combination of level and type of heat-producing composition. In addition, Time-Temperature profiles of each combination were plotted.Results&Discussion: Observations indicated that amount of Heat-producing compositions had significant effect on heat-generated and the best result was obtained with 250g of Heat-producing compositions(p
Reza Farhoosh; Mohammad Shahedi; Ali Sharif
Abstract
The best PH for getting Millard reaction started and Acrylamide formation ranges 7 to 8. PH below the range slows the reaction speed down and the resultant Acrylamide formation delayed. This research assess how Acetic Acid in 0.05, 0.15, 0.25% concentrations together with sourdough may promote acidity ...
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The best PH for getting Millard reaction started and Acrylamide formation ranges 7 to 8. PH below the range slows the reaction speed down and the resultant Acrylamide formation delayed. This research assess how Acetic Acid in 0.05, 0.15, 0.25% concentrations together with sourdough may promote acidity in bread dough and how they can cause a reduction of acrylamide content in Sangak bread [an Iranian traditional bread]. Here the acrylamide is assessed after it was derived and then transferring it to gaseous chromatography with ion indicator. The concentration of acrylamide in Sangak breads made of sourdough with 0.05, 0.15 and 0.25% of acid acetic showed a decrease of 73.47, 81.50 and 82.10% and also a 90.55, 92.80 and 95.96 % decrease when the bread has been made of the same compounds and yeast. The acidity of compounds with acidity rate of 0.05, 0.15 and 0.25% in Sangak bread made of yeast equates to 0.12, 0.14 and 0.17% (normal) respectively; while these values for Sangak breads made of sourdough stand at 0.16, 0.18 and 0.21% (normal). Therefore, decreased acrylamide can be attributed to increased acidity of dough.
Javad Tavakoli; Mohammad Hossein Hadad Khodaparast; Reza Esmaeilzadeh kenari; Mahmoud Aminlari; Ali Sharif
Abstract
In this study, antioxidant activity of kolkhung skin oil, baneh skin oil and seasame oil were compared. The ratio between polyunsaturated to saturated fatty acids (PUFA/SFA) of kolkhung skin oil, bane skin oil and seasame seed oil were 0.52, 0.26 and 3.06, respectively. Total phenolic contents of kolkhung ...
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In this study, antioxidant activity of kolkhung skin oil, baneh skin oil and seasame oil were compared. The ratio between polyunsaturated to saturated fatty acids (PUFA/SFA) of kolkhung skin oil, bane skin oil and seasame seed oil were 0.52, 0.26 and 3.06, respectively. Total phenolic contents of kolkhung skin oil, bane skin oil and seasame seed oil were 99.67, 645.73 and 81.72 mg/kg, respectively. Total tocopherol content of kolkhung skin oil (2154.3mg/kg) was significantly higher than those of the other investigated oils, followed by seasame seed oil and bane skin oil ( 993.69 and 648.91 mg/kg, respectively). Antioxidant activity of the three mentioned oils were determined by DPPH, FRAP and rancimat tests. Antioxidant activity of kolkhung skin oil was significantly higher than those of the other investigated oils, followed seasame seed oil and bane skin oil, respectively. Also it was found a correlation between amount of antioxidant compounds of oils and their antioxidant activity.
Mohammad Reza Edalatian Dovom; Sara Khoshnoudi; Ali Sharif
Abstract
Pistachio nut is one of the most important export crops in Iran. For prevention of rancidity and to ensure good quality, pistachio must be harvested in a short time and be prepared for drying in 24h.The Ohadi variety of Iranian raw dry pistachio nuts was selected for the experiments. Instrumental hardness ...
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Pistachio nut is one of the most important export crops in Iran. For prevention of rancidity and to ensure good quality, pistachio must be harvested in a short time and be prepared for drying in 24h.The Ohadi variety of Iranian raw dry pistachio nuts was selected for the experiments. Instrumental hardness and Sensory characteristics of pistachio nuts such as: flavor , texture and total acceptance were measured in 3 types of packaging (normal air or %21 02 , Vacuum and Oxygen Scavenger), 3 different temperatures (25,35 and 55) during 3 month storage.
Results showed that the effect of temperature, time storage and interaction effects of packaging and temperature , packaging and time storage on instrumental hardness were significant (P
Ghadir Rajabzadeh; Gholamreza Malakzadeh; Ali Sharif
Abstract
بررسی تأثیر نوع حلال و روش استخراج بر میزان اولئورزین به دست آمده از زعفران
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بررسی تأثیر نوع حلال و روش استخراج بر میزان اولئورزین به دست آمده از زعفران
