Composición, propiedades, estabilidad y comportamiento térmico del aceite de semilla de tamarindo (Tamarindus indica)

The composition, thermal stability and phase behavior of tamarind (Tamarindus indica) seed oil were analyzed to contribute to the exploration of their potential uses. The oil was extracted from the kernel of the tamarind seed with hexane, and its main physical, chemical and thermal properties were analyzed by infrared spectrometry, gas chromatography-mass spectrometry, DSC, and TGA. The results showed that the tamarind seed had a 3.76 ± 0.20% oil with a saponification index of 174.80 ± 9.87 mg KOH/g and the major fatty acids were lignoceric (20.15%), oleic (18.99%) and palmitic (11.99%). Stearic, behenic, linoleic, arachidic, and other fatty acids were also present. TGA and DSC showed that in an inert atmosphere, the triacylglycerols of tamarind seed oil (TSO) are decomposed in a single stage that starts at 224.1 °C and in an air atmosphere in three stages, initiating its decomposition at 218 °C. The TSO showed crystallization and fusion curves with a single maximum peak with Tonset and Toffset of 20.16 and ?38.8 °C and ?22.2 and 28.6 °C, respectively. The solid fat profile of the oil showed a semi-solid and liquid consistency in the ambient temperature range. The composition, thermal and phase behavior showed that TSO is potentially useful for alimentary, pharmacological, and cosmetological purposes.La composición, estabilidad y comportamiento térmico del aceite de semilla de tamarindo (Tamarindus indica) fueron analizadas con el fin de contribuir al conocimiento de sus potenciales usos. El aceite fue extraído del núcleo de la semilla con hexano y analizado mediante sus principales propiedades físicas, químicas y térmicas mediante espectrometría infrarroja, cromatografía de gases, espectroscopia de masas, calorimetría (DSC) y termogravimetría (TGA). Los resultados mostraron que las semillas del tamarindo tuvieron un contenido de aceite de 3,76 ± 0,20%, con un índice de saponificación de 174,80 ± 9,87mg KOH/g y ácidos grasos mayoritarios: Lignocérico (20,15%), oleico (18,99%), palmítico (11,99%) y en cantidades menores los ácidos esteárico, behénico, linoleico y araquídico, entre otros. El análisis mediante TGA y DSC mostró que la temperatura inicial de descomposición del aceite fue de 224,1 °C en una sola etapa en atmósfera inerte y en atmósfera de aire fue a 218 °C en tres etapas. El aceite mostró curvas de cristalización y fusión con un solo máximo, iniciándose y finalizando estos cambios de fase a 20,16 y -38,8 °C, and -22,2 y 28,6 °C, respectivamente. Estas propiedades mostraron que el aceite de la semilla de tamarindo tiene potenciales aplicaciones en alimentos y productos farmacológicos y cosméticos

Caracterización fisicoquímica y comportamiento térmico del aceite de “almendra” de guanábana (Annona muricata, L)

In this work some physicochemical properties and the thermal behavior and stability of sour sop or guanabana (Annona muricata) seed “almond” oil were studied by means of chemical, DSC and TG analysis. The results showed that the almond has 2.5% ash, 17.9% crude fiber, 15.7% protein, 26.0% de carbohydrates and 37.7% oil (dry base). The composition of almond oil showed 68.5% unsaturated fatty acids, mainly oleic and linoleic, and some palmitoleic acids, and 31.5% saturated, principally palmitic and stearic fatty acids; refraction index was 1.468 and saponification and iodine value were 168.2 and 87.0, respectively. DSC thermal analysis showed that oil crystallization initiates at -4.5 °C and ends at -79.0 °C with a crystallization enthalpy of 48.2 J/g; the oil melts in a temperature range from -42.4 to +16.9 °C, with a maximum peak at -15 °C and a fusion enthalpy of 80.5 J/g. The oil remained liquid at refrigeration temperatures with minimal SFC and free of crystals at temperatures over 10 °C. TG analysis showed that the thermal decomposition of the oil in a N2 atmosphere starts at 380 °C and ends at 442 °C, with a maximum decomposition rate at 412 °C. Under oxidizing conditions its decomposition begins at 206 °C and concludes at 567 °C. In accordance with this study, sour sop almond seed contains large amounts of an oil that possesses similar characteristics to those of salad and cooking oils.En esta investigación se estudiaron las propiedades físicoquímicas y el comportamiento térmico, mediante calorimetría diferencial de barrido y termogravimetría, del aceite extraído de las “almendras” de las semillas de guanábana (Annona muricata, L). Los resultados mostraron que las almendras de las semillas de guanábana contienen 2.5% de cenizas, 17.9% de fibra cruda, 15.7% de proteínas, 26.0% de carbohidratos y 37.7% de aceite (base seca). El aceite de las almendras de guanábana mostró una composición con predominio de ácidos grasos insaturados (68.5%) mayoritariamente oleico y linoleico y menores cantidades de palmitoleico y linoleico, principalmente; los ácidos grasos saturados fueron principalmente palmítico y esteárico (31.5%), el índice de refracción fue de 1.468, el valor de saponificación y de yodo fueron de 168.2 y 87.0 respectivamente. El análisis térmico mostró que este aceite inicia su cristalización a -4.5 °C y termina a los -79.0 °C con una entalpía de cristalización de 48.2 J/g y funde en un intervalo que va de -42.4 a 16.9 °C con un máximo de fusión a los -15.4 °C y una entalpía de fusión de 80.5 J/g. El contenido de grasa sólida (SFC) fue mínimo a temperaturas de refrigeración, manteniéndose líquido y libre de cristales a temperaturas superiores a los 10 °C. El análisis termogravimétrico mostró que la descomposición térmica del aceite en atmósfera inerte se inicia a los 380 °C y termina a los 442 °C con un valor máximo en la velocidad de descomposición a los 412 °C. En atmósfera oxidante el aceite inicia su descomposición a los 206 °C y concluye a 567 °C. De acuerdo con las características estudiadas las almendras de las semillas de guanábana tiene un alto contenido de aceite y éste posee características propias de los aceites de mesa

Whistle classification ofsympatric false killer whale populations in Hawaiian waters yields low accuracy rates

Funding for passive acoustic data collection during the shipboard cetacean line-transect surveys was provided by PIFSC, SWFSC, NOAA Fisheries Pacific Islands Regional Office, and NOAA Fisheries Office of Protected Resources (OPR) for HICEAS 2010, PIFSC for PICEAS, PACES and HITEC, and PIFSC, OPR, NOAA Fisheries Office of Science and Technology, Chief of Naval Operation Environmental Readiness Division and Pacific Fleet, and Bureau of Ocean Energy Management for HICEAS 2017. Funding for passive acoustic data analysis was provided by PIFSC and the National Science Foundation Graduate Research Fellowships Program.Cetaceans are ecologically important marine predators, and designating individuals to distinct populations can be challenging. Passive acoustic monitoring provides an approach to classify cetaceans to populations using their vocalizations. In the Hawaiian Archipelago, three genetically distinct, sympatric false killer whale (Pseudorca crassidens) populations coexist: a broadly distributed pelagic population and two island-associated populations, an endangered main Hawaiian Islands (MHI) population and a Northwestern Hawaiian Islands (NWHI) population. The mechanisms that sustain the genetic separation between these overlapping populations are unknown but previous studies suggest that the acoustic diversity between populations may correspond to genetic differences. Here, we investigated whether false killer whale whistles could be correctly classified to population based on their characteristics to serve as a method of identifying populations when genetic or photographic-identification data are unavailable. Acoustic data were collected during line-transect surveys using towed hydrophone arrays. We measured 50 time and frequency parameters from whistles in 16 false killer whale encounters identified to population and used those measures to train and test random forest classification models. Random forest models that included three populations correctly classified 42% of individual whistles overall and resulted in a low kappa coefficient, κ = 0.15, indicating low agreement between models, and the true population. Whistles from the MHI population showed the highest correct classification rate (52%) compared to pelagic and NWHI whistles (42 and 36%, respectively). Pairwise random forest models classifying pelagic and MHI whistles proved slightly more accurate (62% accuracy, κ = 0.24), though a similar pelagic-NWHI model did not (56% accuracy, κ = 0.12). Results suggest that the time-frequency whistle characteristics are not suitable to confidently classify encounters to a specific false killer whale population, although certain features of whistles produced by the endangered MHI population allow for overall higher classification accuracy. Inclusion of other vocalization types, such as echolocation clicks, and alternative whistle variables may improve correct classification success for these sympatric populations.Publisher PDFPeer reviewe

Thermal and storage stability of color in juice and fructose syrup from sugar cane

82-88<span style="font-size:11.0pt;font-family: " times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";mso-bidi-font-family:="" mangal;mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:="" hi"="" lang="EN-US">In this paper the thermal stability of the color of purified, guarapoa and clarified, sugar cane juices after treatment with activated carbon and ultrafiltration was studied, and the color stability during the storage of fructose syrup made from them with S. cerevisiae invertase treatment, were evaluated. The results showed that the purification treatments removed up to 99% of the color juices. The remnant color of these purified juices increased with heat treatment at 100°C and 1 h duration, this increment being dependent on the type of purification treatment, the invertase treatment of the sucrose contained in them, and the pH of the juice. Syrups prepared from these purified and hydrolyzed juices had soluble solids over 50°Brix with a color of 25.44 IU for guarapo’s cane juice syrup and 76.33 IU for the clarified juice syrup. They showed increases in color during storage at room temperature reaching around 500 for the first and 1000 IU for the second one after 8 weeks. In refrigerated conditions the syrups showed more stability in their pH value and color. After 10 weeks of storage at 8°C, the color levels were 63.3 and 116.3 IU for guarapo and clarified juice syrups, respectively, with optical densities (OD) lesser than 0.050 ODU, corresponding subjectively to a light straw color.</span