Search

Oxidation reactions in edible oils and fats are regarded as a cause of spoilage. Use of antioxidants can prevent oxidation. In this research, effects of adding three essential oils (cumin, savory and cardamom) at three different concentrations (0.2, 0.4 and 0.6 %, v/v) on acid value, peroxide value, induction period and flavor of soybean oil were evaluated at different storage times and temperatures according to Taguchi's experimental design. Based on the results of this study, type of essential oil, its concentration, storage temperature and storage time indicated significant effects (probability (P) <0.05) on acid value, peroxide value and induction period. However, savory and cardamom showed the highest impact on the evaluated parameters having the most effect on the induction period. Also, based on the results obtained for acid value, all the essential oils from this study indicated significant effects on the acid value. Cumin and savory showed significant effects on the peroxide value. Soybean oil containing the essential oils from this study had good flavor and high desirability with no clear preference among the three essential oils on the flavor and desirability by the sensory panel (P>0.05). In addition, two concentrations of 0.4 and 0.6 (%, v/v) can be regarded as suitable concentrations for reducing free fatty acids as well as peroxide value and enhancing the induction period of soybean oil. Concentration of essential oil within the studied range did not show any significant effect on the flavor of soybean oil. Two temperatures of 20 and 30oC were found to be optimal temperatures for enhancing induction period and reducing the peroxide value of soybean oil. Effects of storage time and temperature on the acid value were also significant (P < 0.05). Storage times of 2 and 4 months were found to be appropriate storage times for optimum induction period of soybean oil, but storage times of 2 and 6 months were optimal times for minimum peroxide value. Increase in the storage time and temperature caused a decrease in the flavor and desirability of the oil. The results of this study showed that the essential oils can be suggested as natural antioxidants in oil industry. [ABSTRACT FROM AUTHOR]

Leutea kurdistanicaMozaff. from Apiaceae family is an endemic herb growing wild in Iran. The essential oil variability of a population ofL. kurdistanicaat different phenological stages, namely the vegetative and flowering stages was studied for the first time by GC-FID and GC-MS. A total of 26 components were identified at the vegetative and flowering stages representing 98.5 and 99.3 % (w/w) of the oil, respectively. The ranges of major constituents were as follow: α-asarone (50.5-62.5 %), elemicin (16.4-22.5 %), α-phellandrene (1.3-5.9 %) and α-pinene (1.6-5.4 %). α-Asarone can be used for a wide range of applications in pharmaceutical and food industries. [ABSTRACT FROM AUTHOR]

Saffron is the commercial name of the dried stigmas ofCrocus sativusL. flower. Due to the high cost of saffron, adulteration sometimes occurs in the local market. In this study, the aroma fingerprints of saffron, saffron with yellow styles, safflower, and dyed corn stigma were detected by an electronic nose system. The features of the obtained signals from electronic nose system were extracted and used for data analysis. In this work, principal component analysis was used and the results were confirmed by back propagation artificial neural networks. The results revealed that the system can recognize the saffron adulteration satisfactorily. As a conclusion, it was found that the electronic nose could provide good separation of the saffron and adulterated one (safflower and other adulteration) as 100 and 86.87% classification accuracy, respectively, by means of artificial neural networks. The electronic nose was able to differentiate non-adulterated and adulterated saffron at higher than 10% adulteration level successfully. [ABSTRACT FROM PUBLISHER]

Compared to the classical methods of analysis, advanced instrumental methods have received increasing attention due to their highly precise analysis of food micro-/macro-structure. Due to its widespread popularity, yogurt has been the subject of numerous studies. This article discusses major advanced instrumental methods applied to the analysis of set/stirred yogurt reported in the literature. Discussed analytical methods have been categorized into two parts, namely chemical analysis methods (including flavor analysis of yogurt, analysis of milk constituents, and assays of indexes), and structural analysis methods (including textural and rheological analysis as well as microstructural analysis). [ABSTRACT FROM AUTHOR]