Search Results (6)

The objective of this work was to characterize the morphology and physicochemical properties of 15 genotypes of native beans from the province of Jujuy, Argentina, 10 of which are ñuñas. The morphological descriptors used were length, width, thickness, and color. Hydration capacity (HC), popping yield (PY), proximal composition, and 100-seed weight (100 W) were also determined. The ñuñas presented rounded shapes and, in general, were smaller than beans since lower values of length and 100 W were observed (9–12 mm and 31.4–48.8 g, respectively, versus 13–15 mm and 40–55 g for beans). No differences were observed between both groups in width (8–7.5 mm), while thickness was more variable in ñuñas (5.8–7.3 mm versus 5.8–6.7 mm for beans). The ñuñas ranged in colors, including whitish, brown, purple, and reddish examples, with a mottled, rhomboid bicolor, and tricolor patterns. The beans ranged from light brown to dark purple, either single-colored or with wide bicolored stripes. Darker colors might indicate the presence of polyphenols and anthocyanin. The physicochemical properties depended on the genotype; the ñuñas presented higher HC (50–67%) and PY (20–36%). The protein content—a key characteristic of legumes—varied between 18 and 25% for all the varieties studied, while lipids ranged from 0.23 to 1.29%. In conclusion, these different characteristics of each genotype could exhibit varying behaviors in response to treatments applied for industrialization. In the canning industry, high values of HC are preferred, while PY describes the ability of ñuñas to expand when exposed to heat. Full article

The bean (Phaseolus vulgaris L.) known as the ñuña, numia, or Andean popping bean, native to the central Andes of Peru, is often consumed as a snack food after a quick toasting process. The characterization of two of its varieties, red and gray ñuña beans, was performed to determine their proximate composition, total phenolics, and antioxidant activity. Moisture content ranged from 12.67% (red ñuña bean) to 11.94% (gray ñuña bean); fat content varied from 1.77% (red ñuña bean) to 1.44% (gray ñuña bean); protein content was high, with a content range from 23.90% (red ñuña bean) to 26.81% (gray ñuña bean); ash content ranged from 4.04% (red ñuña bean) to 3.88% (gray ñuña bean); and a high content of carbohydrates was also found (from 57.60 to 55.94%). The phenolic compounds were consistently higher according to particle size, and the total phenolic content varied from 8589 µg of gallic acid equivalent (GAE)/g powder (red ñuña bean) to 3478 µg GAE/g powder (gray ñuña bean), with antioxidant activity varying from 9879 µg trolox/g powder (red ñuña bean) to 5539 µg trolox/g powder (gray ñuña bean). Food prototypes were then developed with the hydrolyzed proteins from ñuña beans, mashua (Tropaeolum tuberosum) tuber flour, purple corn (Zea mays L.) flour, and pota (Dosidicus gigas) by-product meal with a high content of protein and omega-3 acids (~50% eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) on total fat). Full article

The tectonic evolution of the Siberian Cratonic margins offers important clues for global paleogeographic reconstructions, particularly with regard to the complex geological history of Central Asia and Precambrian supercontinents Columbia/Nuna and Rodinia and its subsequent breakup with the opening of the Paleo-Asian Ocean. Here, we present an overview of geochemical, petrological, and geochronological data from a suite of various rocks to clarify the age, tectonic settings, and nature of their protolith, with an emphasis on understanding the tectonic history of the Yenisey Ridge fold-and-thrust belt at the western margin of the Siberian Craton. These pre-Grenville, Grenville, and post-Grenville episodes of regional crustal evolution are correlated with the synchronous successions and similar style of rocks along the Arctic margin of Nuna-Columbia and Rodinia and support the possible spatial proximity of Siberia and North Atlantic cratons (Laurentia and Baltica) over a long period ~1.4–0.55 Ga. Full article

The South China Craton comprises the Yangtze and Cathaysia blocks and is one of the largest Precambrian continental blocks in East Asia. However, the early geological and geographical evolution of the Cathaysia block is relatively poorly understood, due to the sparse exposure of pre-Neoproterozoic rocks and reworking during Phanerozoic polyphase magmatism and metamorphism. In this contribution, we carried out detrital zircon U-Pb geochronology and sedimentary analyses on five Proterozoic meta-sedimentary rocks collected from the northeastern Cathaysia block, which belong to the previously defined Chencai, Mayuan, and Mamianshan Groups (strata). LA-ICP-MS U-Pb dating results of the detrital zircons show various ~1.85–1.35 Ga maximum depositional ages. They are significantly older than the previously constrained Neoproterozoic formation ages of these Proterozoic strata of northeastern Cathaysia, suggesting that their deposition and formation were probably initiated as early as the late Paleoproterozoic. Provenance analyses reveal that the late Paleoproterozoic to early Mesoproterozoic detrital zircons with igneous-origin were derived from in situ contemporary crystalline basements in eastern Cathaysia. In addition, by implication, the easternmost part of Cathaysia was probably an emerged area (i.e., the “proto-Cathaysia Land”) under active erosion. It had a ~NWW orientation and provided detrital sediments to the neighboring marine basin (i.e., the Cathaysia Sea) during the late Paleoproterozoic to early Mesoproterozoic. Finally, the Paleoproterozoic evolution of Cathaysia was involved in the assembly of the Nuna supercontinent. Our results, together with the published data, reveal a distinct late Paleoproterozoic (~1.8 Ga) detrital zircon age peak, which seems to support the view that eastern Cathaysia had close tectonic affinities with terranes such as the Precambrian terranes of current northern India, in the framework of the Nuna supercontinent reconstruction. Full article

The Mesoproterozoic Gaoyuzhuang and Wumishan Formations are major geothermal reservoirs in the Hebei Province, North China. Compared to the exploration of geothermal resources and heat-controlling structures, carbon and oxygen isotopic records of the two formations are limited. Here, we present integrated field, petrological, geochemical, carbon, and oxygen isotopic data of carbonate rocks from the Gaoyuzhuang and Wumishan Formations. The Wumishan Formation is characterized by higher CaO and MgO contents and lower SiO₂ contents than the Gaoyuzhuang Formation, indicating that the source of the Wumishan Formation likely contains less terrigenous clastic materials. The two formations have low total rare earth element contents, similar to marine carbonate rocks. They show different Eu and Ce anomalies, Al/(Al + Fe + Mn) and Fe/Ti ratios, and (Co + Ni + Cu) contents. They generally show similar carbon isotopic compositions, whereas the carbonate rocks of the middle-upper Gaoyuzhuang Formation show lower δ¹⁸O values than the samples from the Wumishan and lower Gaoyuzhuang Formations. These data suggest that the two formations have experienced different transgressive–regressive cycles and that their sedimentary environments varied and were unstable in different sedimentary periods. The middle-upper Gaoyuzhuang Formation was likely affected by hydrothermal fluids, whereas the Wumishan Formation is composed of normal seawater deposits. Integrated evidence reveals that both of the Mesoproterozoic Gaoyuzhuang and Wumishan Formations were deposited in rift environments caused by the breakup of the Columbia/Nuna supercontinent. Full article

Zircon age peaks at 2100–1650 and 1200–1000 Ma correlate with craton collisions in the growth of supercontinents Nuna and Rodinia, respectively, with a time interval between collisions mostly <50 Myr (range 0–250 Myr). Collisional orogens are two types: those with subduction durations <500 Myr and those ≥500 Myr. The latter group comprises orogens with long-lived accretionary stages between Nuna and Rodinia assemblies. Neither orogen age nor duration of either subduction or collision correlates with the volume of orogen preserved. Most rocks preserved date to the pre-collisional, subduction (ocean-basin closing) stage and not to the collisional stage. The most widely preserved tectonic setting in Proterozoic orogens is the continental arc (10%–90%, mean 60%), with oceanic tectonic settings (oceanic crust, arcs, islands and plateaus, serpentinites, pelagic sediments) comprising <20% and mostly <10%. Reworked components comprise 20%–80% (mean 32%) and microcratons comprise a minor but poorly known fraction. Nd and Hf isotopic data indicate that Proterozoic orogens contain from 10% to 60% of juvenile crust (mean 36%) and 40%–75% reworked crust (mean 64%). Neither the fraction nor the rate of preservation of juvenile crust is related to the collision age nor to the duration of subduction. Regardless of the duration of subduction, the amount of juvenile crust preserved reaches a maximum of about 60%, and 37% of the volume of juvenile continental crust preserved between 2000 and 1000 Ma was produced in the Great Proterozoic Accretionary Orogen (GPAO). Pronounced minima occur in frequency of zircon ages of rocks preserved in the GPAO; with minima at 1600–1500 Ma in Laurentia; 1700–1600 Ma in Amazonia; and 1750–1700 Ma in Baltica. If these minima are due to subduction erosion and delamination as in the Andes in the last 250 Myr; approximately one third of the volume of the Laurentian part of the GPAO could have been recycled into the mantle between 1500 and 1250 Ma. This may have enriched the mantle wedge in incompatible elements and water leading to the production of felsic magmas responsible for the widespread granite-rhyolite province of this age. A rapid decrease in global Nd and in detrital zircon Hf model ages between about 1600 and 1250 Ma could reflect an increase in recycling rate of juvenile crust into the mantle; possibly in response to partial fragmentation of Nuna. Full article