ABSTRACT
Fingerprinting techniques, which utilize the unique chemical and physical properties of food samples, have emerged as a promising approach for food authentication and traceability. Recent studies have demonstrated significant advancements in food authentication through the use of fingerprinting methods, such as multivariate statistical analysis techniques applied to trace elements and isotope ratios. However, further research is required to optimize these methods and ensure their validity and reliability in real-world applications. In this study, the inductively coupled plasma mass spectrometry (ICP-MS) analytical method was employed to determine the content of 21 elements in 300 cashew nut (Anacardium occidentale L.) samples from 5 brands. Multivariate statistical methods, such as principal components analysis (PCA), were employed to analyze the data obtained and establish the provenance of the cashew nuts. While cashew nuts are widely marketed in many countries, no universal method has been utilized to differentiate the origin of these nuts. Our study represents the initial step in identifying the geographical origin of commercial cashew nuts marketed in Vietnam. The analysis showed significant differences in the means of 21 of the 40 analyzed elements among the cashew nut samples from the 5 brands, including 7Li, 11B, 24Mg, 27Al, 44Ca, 48Ti, 51V, 52Cr, 55Mn, 57Fe, 60Ni, 63Cu, 66Zn, 93Nb, 98Mo, 111Cd, 115In, 121Sb, 138Ba, 208Pb, and 209Bi. The PCA analysis indicated that the cashew nut samples can be accurately classified according to their original locations. This research serves as a prerequisite for future studies involving the combination of elemental composition analysis with statistical classification methods for the accurate establishment of cashew nut provenance, which involves the identification of key markers for the original discrimination of cashew nuts.
ABSTRACT
Rhodomyrtus tomentosa (Ait.) Hassk (RTH) is a plant distributed mainly in Southeast Asia that has long been used as a food or a folk remedy for various ailments. Anthocyanins extracted from RTH have received the attention of researchers as well as manufacturers in exploiting the application of this plant for commercial purposes. Several extraction methods have been performed, however, concerns about new extraction methods, extraction conditions as well as stability of anthocyanins during storage are issues that need to be evaluated. In this study, the process of extracting anthocyanins by microwave method and the stability of anthocyanins in RTH extraction were investigated. For the extraction method, the influence of solvent concentration (30-70%), application ratio (10:1-1:1 mL/g), microwave power (100-500W), and time (1-9 min) have been evaluated. A first-order kinetic model was also used to evaluate the variation of anthocyanin content during storage at different conditions, including 5 °C (refrigerator), 30 °C (room temperature), and 45 °C (incubator). The study results showed that the anthocyanin content had the greatest value of 137.54 mg/L when extracted with 50% ethanol solvent with the material/solvent ratio of 1:3 (g/ml) microwave power is 200W for 5 min. The first-order decomposition kinetics model showed that the t1/2 values of the RTH extract were 69.64, 28.66, and 19.8, respectively, for the storage temperatures of 5 °C, 30 °C, and 45 °C, respectively. During storage, anthocyanin content tends to decrease more rapidly under high-temperature conditions. In addition, a close correlation between anthocyanin content and antioxidant capacity was recorded at a high significance level R2 > 0.98.
ABSTRACT
Cashew apples, a by-product accrued during the manufacture of cashew nuts, have abundant nutritional values but are not widely utilized due to the presence of substances that cause acrid taste. In this study, we attempted the production of a dried jelly cashew apple product and optimized three main processing stages including blanching, osmotic, and drying. The results showed suitable conditions at 6 mm thickness in the blanching process. The osmotic process recorded a temperature of 35°C, within 1.5 h, the ratio of sugar syrup/ingredient 2:1 with sugar syrup 60 Bx, and the addition of 0.6% citric acid on the total weight of ingredients and 0.02% CaCl2. The drying process at 55°C within 267 min had the highest ascorbic acid content (TAA), total phenolic content (TPC), and content of tannin compounds (TTC) retention. These parameters refer to a product that has good organoleptic acceptability in terms of taste, acrid content, and a high ability to retain major nutrients. Furthermore, the product recovery efficiency is 21.45%. Jelly drying cashew apples (JDC) are formed to help take advantage of by-products, contributing to adding value for the cashew industry.
ABSTRACT
Vertical heterostructures from two or more than two two-dimensional materials are recently considered as an effective tool for tuning the electronic properties of materials and for designing future high-performance nanodevices. Here, using first principles calculations, we propose a GeC/C2N van der Waals heterostructure and investigate its electronic and optical properties. We demonstrate that the intrinsic electronic properties of both GeC and C2N monolayers are quite preserved in GeC/C2N HTS owing to the weak forces. At the equilibrium configuration, GeC/C2N HTS forms the type-II band alignment with an indirect band gap of 0.42 eV, which can be considered to improve the effective separation of electrons and holes. Besides, GeC/C2N vdW-HTS exhibits strong absorption in both visible and near ultra-violet regions with an intensity of 105 cm-1. The electronic properties of GeC/C2N HTS can be tuned by applying an electric field and vertical strains. The semiconductor to metal transition can be achieved in GeC/C2N HTS in the case when the positive electric field of +0.3 V Å-1 or the tensile vertical strain of -0.9 Å is applied. These findings demonstrate that GeC/C2N HTS can be used to design future high-performance multifunctional devices.
