We investigated the potential of two oil extracts from seeds of Colliguaya integerrima (CIO) and Cynara cardunculus (CO) to use as nutritionally edible oils. For this purpose, oil quality was accessed by determining the fatty acid composition, peroxide value, acid value, iodine value, saponification number, phenolic contents, and oxidative stability during thermally induced oxidation of CIO and CO oils and compared to those of extra-virgin olive oil (EVOO). The chemical composition results demonstrated that both oils could be nutritional sources of essential unsaturated fatty acids. Moreover, according to the gravimetric analysis, the main decomposition step occurred in the temperature range of 200–420 °C, showing a similar thermal behavior of EVOO oil. However, CO and EVOO oils showed a higher phenolic content at degradation onset temperature (T0) in contrast with CIO oil. The antioxidant activity of the different studied oils showed a direct correlation with the phenol contents, up to temperatures around 180 °C, where the percentage of free radical scavenging assay for EVOO was higher than CO in contrast with the TPC values. Finally, we analyzed the minor components before and after heating CIO and CO at 180 °C by gas chromatography–mass spectrometry (GC–MS) using library search programs.

In this study, we investigated the potential of two non-edible oil extracts from seeds of Colliguaja integerrima (CIO) and Colliguaja salicifolia (CSO) to use as a renewable source for polyols and, eventually, polyurethane foams or biodiesel. For this purpose, two novel polyols from the aforementioned oils were obtained in a one-single step reaction using a mixture of hydrogen peroxide and acetic acid. The polyol derivatives obtained from the two studied oils were characterized by spectral (FTIR, 1H NMR, and 13C NMR), physicochemical (e.g., chromatographic analysis, acid value, oxidizability values, iodine value, peroxide value, saponification number, kinematic viscosity, density, theorical molecular weight, hydroxyl number, and hydroxyl functionality) and thermal (TGA) analyses according to standard methods. Physicochemical results revealed that all parameters, with the exception of the iodine value, were higher for bio-polyols (CSP and CIP) compared to the starting oils. The NMR, TGA, and FTIR analyses demonstrated the formation of polyols. Finally, the OH functionality values for CIP and CSP were 4.50 and 5.00, respectively. This result indicated the possible used of CIP and CSP as a raw material for the preparation of polyurethane rigid foams.

No abstract

No abstract

F. Ponce, Y. Mirabal-Gallardo, A. Versari, and V.F. Laurie. 2018. The use of cation exchange resins in wines: Effects on pH, tartrate stability, and metal content. Cien. Inv. Agr. 45(1): 82-92. Treating wines with cation exchange resins allows the reduction of pH and contributes to limiting the formation of tartrate salts by exchanging cations such as potassium with hydrogen ions. This manuscript summarizes the results of a series of laboratory and winery-scale trials performed with the aim of evaluating the ion exchange process and its effects on the chemical composition of the treated samples. The laboratory-scale results showed that both the procedure employed for the activation of resins and the chemical composition of the wines affected the extent of the chemical changes occurring during the treatment. As such, the winery-scale trials showed that the resin-treated wines have significantly lower pH, higher total acidity, less tartrate formation (measured by weight), and a reduced amount of most metals analyzed. Wine samples blended with approximately 20% of cation exchange-treated samples (by volume) showed no signs of tartrate instability when assessed by a quick qualitative cold test.

Multi-element analysis and differentiation of Chilean wines using mineral composition and multivariate statistics. 2018. Cien. Inv. Agr. 45(2): 181-191. The concentration of seventeen metal elements was analyzed in 130 commercial samples of Chilean wines, using flame atomic absorption spectroscopy (AAS) and inductively coupled plasma-mass spectrometry (ICP-MS). The elements analyzed were within the usual concentration ranges previously reported in other wine regions (for example: Fe, 2.08 ± 0.99 mgL-1 ; Zn, 0.71 ± 0.44 mg L-1 ; K, 788± 219 mg L-1 ; and Na, 14.62 ± 8.6 mg L-1). When the metal content of the samples was compared among geographic areas, significant differences in the concentration of K, Na, Mn, Mg, Zn, and Cr were observed (p ≤ 0.05). Moreover, principal component and linear discriminant analyses, used to discriminate wines according to geographic area, obtained adjustments above 90% for white wines and over 70% for red wines.

No abstract

No abstract