Andean roots and tubers crops as sources of functional foods

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.

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.

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.

Microorganisms present in artisanal fermented food from South America

Artisanal fermented products (foods and beverages) are produced in an artisanal way in many countries around the world. The main purpose of fermentation is to preserve the food, improve its safety, increase the nutritional and health-promoting value and add specific flavours. In South America, there is a great variety of fermented food produced in an artisanal way. Different raw materials are used such as potatoes, sweet potato, cassava, maize, rice, milk (cow, ewe, goat) and meat (beef, goat, lamb, llama and guanaco). Some of these fermented foods are typical of the region and are part of the culture of native communities, e.g. tocosh, masa agria, puba flour, charqui, chicha, champu and cauim among others (indigenous foods). However, other fermented foods produced in South America introduced by mainly European immigration, such as cheeses and dry sausages, and they are also produced in many different parts of the world. In this work, the microbial composition of the different artisanal fermented products produced in South America is reviewed, taking into consideration the associated raw materials, fermentation conditions and methodologies used for their production.

Extraction and Characterization of Proteins from Pachyrhizus ahipa Roots: an Unexploited Protein-Rich Crop

Pachyrhizus ahipa is an unexploited crop known to be rich in proteins compared to other edible roots and tubers. These proteins are not prolamins, thus ahipa represents an interesting new source of ingredients for gluten-free foods. In this work, ahipa proteins (AP) were extracted and partially characterized in pursuit of their use as food ingredients. The effect of ultrasound treatment on protein extraction efficiency was evaluated. AP were characterized by their size, amino acid composition, surface hydrophobicity, intrinsic fluorescence, FTIR spectra, solubility, and thermal and emulsifying properties. AP were efficiently removed from the vegetal tissue using PBS or water, regardless of the use of ultrasound, but not easily recovered by precipitation. This protein fraction was composed of small proteins, with sizes ranging from 9 to 30 kDa, and highly polar. AP resulted particularly rich in aspartic acid (59% of the total amino acid content), for which they can be classified as Asp-rich proteins. Their elevated content of acidic groups was evidenced in the ATR-FTIR spectrum. The amide I band deconvolution as well as the low surface hydrophobicity and denaturation enthalpy indicated that these proteins are mainly unordered structures. The emulsifying properties of AP were enhanced when the concentration was increased from 0.1 to 1% (w/v) but resulted lower than those of soy protein. The high polarity, small size, and low isoelectric point make AP particularly suitable for acidic food matrices.

Assessing the Nutritional Value of Root and Tuber Crops from Bolivia and Peru

All over the world, there are species which may be considered as neglected or underutilized despite their nutritious properties. At present, such crops contribute to food security in isolated areas by providing energy and nutrients in a diversified diet. Such genetic heritage—improved by ancient cultures—is under threat of losing biodiversity as well as the traditional knowledge associated with their cultivation and usage. Among these species, the Andean root and tuber crops (ARTCs) constitute a valuable resource which should be preserved and popularized because of their food and functional properties. We studied three ARTC species (mashua, arracacha, and yacon) to provide data on their composition, essential for increasing their use globally. We compared their nutritional values with the values of more widely used crops. Important differences in nutrient composition among ARTC landraces were found. Mineral nutrients showed significant differences among species. Considerable variations in the contents of prebiotics like fructooligosaccharides or functional elements (antioxidants and glucosinolates) were found among species and intraspecific samples. Certainly, these species are important assets to complement human nutrition and to secure supply of functional elements for healthy diets.