Volume 20, Issue 137 (July 2023)
Abstract
Frankincense is a resinous gum obtained from some species of the Boswellia genus. The use of frankincense for food and medicinal uses dates back to more than five thousand years ago, but despite its importance and application, only 27-35% of it is soluble in water. As most frankincense gum is insoluble, this research used the response surface method to study the effect of different chemical modification conditions (NaOH concentrations (X1), reaction temperatures (X2), and MCA concentrations (X3)) on increasing the solubility percentage. The results of the optimization process of the chemical modification of frankincense gum indicate that the conditions of maximum solubility are equal to 85.49, with a desirability rate of 0.97. Therefore, the concentration of NaOH and MCA equal to 0.048, 0.01 mol, and a temperature of 75 degrees Celsius chose as the best optimization conditions. In addition, the intrinsic viscosity and molecular weight of the native gum were higher than the modified gum under optimal conditions. There is a significant difference between the apparent viscosity of natural gum (18.02 ± 0.726 mPa.s) and modified (17.36 ± 0.681 mPa.s) (p>0.05). The results indicate that native and modified gum in optimal conditions show a shear thinning behavior with increasing shear rate, and their behavior is similar to pseudoplastic. The colorimetric test with image J software indicated that carboxymethylation of frankincense gum led to significant changes (P < 0.05) in the total color difference factor (ΔE) and whiteness index (WI), L*, a*, and b*factor.
Volume 21, Issue 153 (November 2024)
Abstract
Oxidation of fats in food greatly reduces their shelf life and causes food of unacceptable quality to be presented to the customer. In this regard, this research was conducted with the aim of increasing the oxidative stability of sesame oil with nanoliposomes containing the antioxidant extract of yarrow plant. In this study, 6 concentrations of nanoliposomes containing yarrow plant extract (0, 50, 100, 200, 500 and 1000 ppm) were used in sesame oil, and tests such as acidity, peroxide, thiobarbituric acid index, conjugate diene were performed on those oils. And after finding the best concentration of nanoliposome containing yarrow extract, this sample was compared with the sample containing the same amount of free yarrow extract and also the sample with 200 ppm BHT after 7 days of storage at 63 degrees Celsius. The results showed that with increasing storage time, acidity level, thiobarbituric acid index and conjugate diene increased, but with the increase of nanoliposome containing 500 ppm of yarrow extract, these characteristics decreased and then increased. Unlike other characteristics, the peroxide content of the samples decreased from the 5th day onwards. On the other hand, it was found that the sample containing 500 ppm of free yarrow extract had the highest level of acidity, peroxide, thiobarbituric acid index and conjugate diene. The highest oxidative stability (14.21 hours) belonged to the oil with nanoliposome containing 500 ppm of yarrow extract. The dominant fatty acid in sesame oil containing nanoliposome as well as control was linoleic acid, and the use of antioxidants did not significantly change the fatty acid profile of sesame oil. Finally, it can be stated that the use of nanoliposome containing yarrow plant extract is a suitable alternative for synthetic antioxidants available in the market.
