Characterization, mathematical modeling of moisture sorption isotherms and bioactive compounds of Andean root flours.

Andean roots can be used as an alternative to gluten-free food. The objective of this study was to enhance the technological and nutritional properties of Andean root flours to promote their industrial applicability. The water content and activity of the flour were lower than those required to prevent mold growth. The bulk density of the flour was comparable to that of wheat flour. The flour of Ipomoea batatas (L.) Lam. exhibited the lowest water absorption capacity of the tested samples. However, both this flour and Tropaeolum tuberosum Ruiz & Pavón showed a higher fat absorption capacity. The samples exhibited type-II isotherms, indicating that the flours were highly hygroscopic. The Guggenheim, Anderson, and de Boer GAB model showed a higher coefficient of determination in mathematical modeling. The chroma of T. tuberosum Ruiz & Pavón flour was higher than the other samples, which was related to total carotenoids and lycopene. Furthermore, I. batatas (L.) Lam. exhibited the highest phenol value.

Traditional soil fertility management ameliorates climate change impacts on traditional Andean crops within smallholder farming systems.

Global changes, particularly rising temperatures, threaten food security in smallholder mountain communities by impacting the suitability of cultivation areas for many crops. Land-use intensification, associated with agrochemical use and tillage, threatens soil health and overall agroecosystem resilience. In the Andean region, farmers often cultivate crops at multiple elevations. Warming climates have led to a shift in cultivation upslope, but this is not feasible in many areas. Traditional soil fertility management practices together with a focus on traditional (orphan) crops offers promise to cope with rapid climate warming in the region. To understand the impacts of warming and changing nutrient management, we established two side-by-side experiments using the traditional Andean crops Oxalis tuberosa (Oca) and Lupinus mutabilis (Tarwi) at three elevations, each with two fertility treatments (organic and synthetic). Soil and climate data (i.e., temperature and precipitation) were collected throughout the growing season, and crop performance was evaluated through impacts on yield and other growth metrics (e.g., biomass, pest incidence). We used two-way ANOVA to assess the influence of site (elevation) and management type (organic vs. synthetic) on crop performance. Results indicated that warmer climates (i.e., lowest elevation) negatively impact the production and performance of O. tuberosa, but that organic fertilization (sheep manure) can help maintain crop yield and biomass production in warmer conditions relatively to synthetic nutrient inputs. In contrast, L. mutabilis showed accelerated growth in warmer conditions, but grain yield and biomass production were not significantly affected by site and showed no interaction with nutrient management. Our findings highlight that climate warming represents a serious threat to small-scale crop production in the Peruvian Andes and could cause severe declines in the production of locally important crops. Additionally, the continued reliance on traditional crops with organic inputs, instead of synthetic fertilizers, may help support agricultural productivity and resilience under climate change.

Third-Generation Snacks Manufactured from Andean Tubers and Tuberous Root Flours: Microwave Expansion Kinetics and Characterization.

Andean tubers and tuberous roots have nutritional and medicinal properties transferred through ancestral generations. In this study, we aim to promote cultivation and consumption by developing a snack based on these crops. Corn grits were thoroughly mixed with sweet potato, mashua, and three varieties of oca flour (white, yellow, and red) in an 80:20 ratio, and a single-screw laboratory extruder was utilized to produce third-generation (3G) dried pellets. Microwave expansion was studied, and the dried 3G pellets and expanded snacks were characterized. The microwave expansion curves of the dried 3G pellets were adjusted to the Page, logarithmic, and Midilli-Kucuk models. During the characterization, the influence of the raw material composition was observed in sectional expansion, water content, water activity, water absorption, water solubility, swelling, optical and textural properties, and bioactive compounds. According to global color variation (mixture vs. expanded and dried vs. expanded) and bioactive compound analysis, the mashua suffered little chemical change or nutritional loss during the process. The extrusion process was shown to be an ideal method for manufacturing snacks from Andean tuber flours.

Characterization of Second-Generation Snacks Manufactured from Andean Tubers and Tuberous Root Flours.

Andean roots, such as zanahoria blanca, achira, papa China, camote, oca, and mashua, contain high amounts of dietary fiber, vitamins, minerals, and fructo-oligosaccharides. This study aimed to demonstrate the possibility of obtaining healthy second-generation (2G) snacks (products obtained from the immediate expansion of the mixture at the exit of the extruder die) using these roots as raw materials. Corn grits were mixed with Andean root flour in a proportion of 80:20, and a Brabender laboratory extruder was used to obtain the 2G snacks. The addition of root flour increased the water content, water activity, sectional expansion index, hygroscopicity, bulk density, and water absorption index but decreased the porosity. However, all 2G snacks manufactured with Andean root flour showed better characteristics than did the control (made with corn grits) in texture (softer in the first bite and pleasant crispness) and optical properties (more intense and saturated colors). The developed snacks could be considered functional foods due to the high amount of carotenoids and phenolic compounds they exhibit after the addition of Andean root flours. The composition of raw roots, specifically the starch, fiber, and protein content, had the most impact on snack properties due to their gelatinization or denaturalization.

Modification of Oxalis tuberosa starch with OSA, characterization and application in food-grade Pickering emulsions.

The emulsifying properties of Oxalis tuberosa starch (native and chemically modified) were evaluated in Pickering emulsions based on the emulsification index, emulsion stability over time and emulsion morphology. The best conditions of chemical modification were found by esterification of starch with octenyl succinic anhydride (OSA) at a concentration of 3% and a reaction time of 2 h, achieving a degree of substitution of 0.033 ± 0.001. The results obtained using Fourier-transform infrared spectroscopy, a Rapid Visco Analyzer, and differential scanning calorimetry, indicated that the starch underwent a change in its structure and that the insertion of the OSA groups was achieved. The amphipathic characteristics of OSA starch were evaluated by forming oil-in-water emulsions. Various concentrations of OSA-starch granules (1, 2.5 and 5 wt%) were used. A higher concentration of particles produced a smaller droplet size of emulsions (76.5 ± 0.9 µm) compared to those formed at a lower concentration of 1% (92.5 ± 1.0 µm). Therefore, the starch modified with OSA displayed the necessary characteristics to be adsorbed at the oil-water interface, achieving Pickering emulsion stabilization.

Stabilisation of betalains and phenolic compounds extracted from red cactus pear (Opuntia ficus-indica) by spray and freeze-drying using oca (Oxalis tuberosa) starch as drying aid.

The objective of this work was to evaluate the stabilisation of betalains and phenolic compounds extracted from red cactus pear by spray and freeze-drying. After hydroethanolic extraction and partial solvent removal under reduced pressure, the highly coloured extracts were enriched with oca starch and maltodextrin as drying aids in different ratios (100:0, 70:30, and 50:50, oca starch: maltodextrin) prior to spray and freeze-drying. The obtained microencapsulated extract powders were characterised by moisture content, hygroscopicity, solubility and morphology. In addition, the stability of the encapsulated betalains and phenolics was evaluated during storage at room temperature for 105 days. All microcapsules showed high retentions of betacyanins (69.9-86.5% after 105 days), betaxanthins (72.2-81.9%), phenolic compounds (46.5-63.5%) and antioxidant capacity (60.1-64.9%, FRAP method; 49.7-57.5%, ABTS method). The system with 70:30 starch:maltodextrin ratio as drying aids showed the highest values of retention regarding the polyphenol content (63.5%), antioxidant capacity (64.9% to FRAP method) and betacyanin content (86.5%), as well as a low degradation rate constant of betacyanins (1.23 × 10-3 days-1) and a long half-life (563 days). Oca starch used alone or in combination with maltodextrin has been shown to work adequately as a microencapsulating agent and stabilizer of pigments and antioxidants derived from red cactus pear.

Bioactive Potential of Andean Fruits, Seeds, and Tubers.

The Andes is considered the longest continental mountain range in the world. It covers 7000km long and about 200-700km wide and an average height of about 4000m. Very unique plant species are endemic of this area including fruits (e.g., lucuma, cherimoya, sweet pepino, sauco), roots and tubers (potatoes, sweet potatoes, yacón, chicuru, mashua, olluco, etc.), and seeds (quinoa, amaranth, tarwi, etc.). These crops have been used for centuries by the native population and relatively recently have gained the world attention due to the wide range of nutrients and/or phytochemicals they possess. In this chapter, main Andean fruits, seeds, and roots and tubers have been selected and detailed nutritional and functional information is provided. In addition, traditional and current uses are provided and their bioactive potential is reported based on published scientific literature.

Description of Thecavermiculatus andinus n.sp. (Meloidoderidae), a Round Cystoid Nematode from the Andes Mountains of Peru.

Thecavermiculatus andinus n.sp. is described and illustrated from Oxalis tuberosa originally collected in the vicinity of Lake Titicaca high in the Andes mountains of southern Peru. This new species differs markedly front the other two species in the genus, especially in having a much greater female vulval-anal distance and annules with lined punctation on most of the female body with a lacelike pattern restricted to the posterior portion, particularly at the vulva and anus which do not protrude. Females are essentially spherical with protruding neck, white to yellowish in color, and can easily be mistaken for potato cyst nematodes. Among the dozen or more known weed and crop host plants are potato and eggplant. In order to accommodate this new species, the genus Thecavermieulatus is emended. A key to the species of this genus is presented.