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Aqueous suspensions rely on electrostatic interactions among suspended solids, posing a significant challenge to maintaining stability during storage, particularly in the food and pharmaceutical industries, where synthetic stabilizers are commonly employed. However, there is a growing interest in exploring new materials derived from natural and environmentally friendly sources. This study aimed to optimize the stability parameters of a novel Altoandino Nostoc Sphaericum hydrocolloid (NSH) extracted via micro atomization. Suspensions were prepared by varying the pH, gelatinization temperature and NSH dosage using a 23 factorial arrangement, resulting in eight treatments stored under non-controlled conditions for 20 days. Stability was assessed through turbidity, sedimentation (as sediment transmittance), ζ potential, particle size, color and UV-Vis scanning. Optimization of parameters was conducted using empirical equations, with evaluation based on the correlation coefficient (R2), average relative error (ARE) and X2. The suspensions exhibited high stability throughout the storage period, with optimized control parameters identified at a pH of 4.5, gelatinization temperature of 84.55 °C and NSH dosage of 0.08 g/L. Simulated values included turbidity (99.00%), sedimentation (72.34%), ζ potential (-25.64 mV), particle size (300.00 nm) and color index (-2.00), with simulated results aligning with practical application. These findings suggest the potential use of NSH as a substitute for commercial hydrocolloids, albeit with consideration for color limitations that require further investigation.

RESUMO

Modifying starch allows for improvements in its properties to enable improved uses in food matrices, bioplastics, and encapsulating agents. In this research, four varieties of native potato starch were modified by acid treatment, enzymatic treatment, and ethanol precipitation, and their physicochemical, structural, thermal, and techno-functional characteristics were analyzed. According to FT-IR analysis, no influence of the modified starches on the chemical groups was observed, and by scanning electron microscopy (SEM), spherical and oval shapes were observed in the acid and enzymatic treatments, with particle sizes between 27 and 36 µm. In particular, the ethanolic precipitation treatment yielded a different morphology with a particle size between 10.9 and 476.3 nm, resulting in a significant decrease in gelatinization temperature (DSC) and more pronounced crystallites (XRD). On the other hand, the enzymatic treatment showed higher values for z-potential (ζ), and the acid treatment showed lower mass loss (TGA). Acid and ethanolic treatments affected the dough properties compared to native starches. The techno-functional properties showed a decrease in the water absorption index, an increase in the water solubility index, and varied swelling power behaviors. In conclusion, the modification of potato starches through acid, enzymatic, and ethanolic precipitation treatments alters their physicochemical properties, such as swelling capacity, viscosity, and thermal stability. This in turn affects their molecular structure, modifying morphology and the ability to form gels, which expands their applications in the food industry to improve textures, stabilize emulsions, and thicken products. Furthermore, these modifications also open new opportunities for the development of bioplastics by improving the biodegradability and mechanical properties of starch-based plastic materials.

RESUMO

Despite the extensive development of microalgae biotechnology, it still requires new methodologies to lower production costs, especially in the field of biofuel production. Therefore, innovative methods that facilitate operations and enable cost-effective production are important in driving this industry. In this study, we propose a new low-cost and easy-to-use procedure, addressed to the generation of a culture medium for Scenedesmus acutus. The medium was obtained by thermal reduction of a sludge sample from El Ferrol Bay (Chimbote, Peru), whereby we obtained an aqueous medium. Our results indicated that the aqueous medium incorporates all necessary nutrients for microalgae production; allowing a maximum biomass of 0.75 ± 0.07 g/L with 60% of the medium; while high lipids production (59.42 ± 6.16%) was achieved with 20%. Besides, we quantified, in the experimental medium and at the end of the cultures, the levels of inorganic nutrients such as ammonium, nitrites, nitrates, and phosphates; in addition to COD and TOC, which were significantly reduced ( p < 0.05) after 7 days of culture, mainly in the treatment with 20%. These results suggest tremendous potential for sludge reuse, which also entails a cost reduction in microalgae biomass production, with additional positive impacts on large-scale application over highly polluted environments.

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RESUMO

Tara gum, a natural biopolymer extracted from Caesalpinia spinosa seeds, was investigated in this study. Wall materials were produced using spray drying, forced convection, and vacuum oven drying. In addition, a commercial sample obtained through mechanical methods and direct milling was used as a reference. The gums exhibited low moisture content (8.63% to 12.55%), water activity (0.37 to 0.41), bulk density (0.43 to 0.76 g/mL), and hygroscopicity (10.51% to 11.42%). This allows adequate physical and microbiological stability during storage. Polydisperse particles were obtained, ranging in size from 3.46 µm to 139.60 µm. Fourier transform infrared spectroscopy characterisation confirmed the polysaccharide nature of tara gum, primarily composed of galactomannans. Among the drying methods, spray drying produced the gum with the best physicochemical characteristics, including higher lightness, moderate stability, smaller particle size, and high glass transition temperature (141.69 °C). Regarding rheological properties, it demonstrated a non-Newtonian pseudoplastic behaviour that the power law could accurately describe. The apparent viscosity of the aqueous dispersions of the gum decreased with increasing temperature. In summary, the results establish the potential of tara gum as a wall material applicable in the food and pharmaceutical industries.

RESUMO

Germination is an effective strategy to improve the nutritional and functional quality of Andean grains such as quinoa (Chenopodium quinoa Willd.); it helps reduce anti-nutritional components and enhance the digestibility and sensory aspects of the germinated. This work aimed to evaluate the effect of germination (0, 24, 48, and 72 h) on the physicochemical properties, content of bioactive compounds, and antioxidant capacity of three varieties of quinoa: white, red, and black high Andean from Peru. Color, nutritional composition, mineral content, phenolic compounds, flavonoids, and antioxidant activity were analyzed. Additionally, infrared spectra were obtained to elucidate structural changes during germination. The results showed color variations and significant increases (p < 0.05) in proteins, fiber, minerals, phenolic compounds, flavonoids, and antioxidant capacity after 72 h of germination, attributed to the activation of enzymatic pathways. In contrast, the infrared spectra showed a decrease in the intensity of functional groups -CH-, -CH2-, C-OH, -OH, and C-N. Correlation analysis showed that flavonoids mainly contributed to antioxidant activity (r = 0.612). Germination represents a promising alternative to develop functional ingredients from germinated quinoa flour with improved nutritional and functional attributes.

RESUMO

There is a growing emphasis on seeking stabilizing agents with minimal transformation, prioritizing environmentally friendly alternatives, and actively contributing to the principles of the circular economy. This research aimed to assess the stability of a novel spray-dried hydrocolloid from high Andean algae when introduced into an aqueous solution. Nostoc sphaericum freshwater algae were subject to atomization, resulting in the production of spray-dried hydrocolloid (SDH). Subsequently, suspension solutions of SDH were meticulously prepared at varying pH levels and gelling temperatures. These solutions were then stored for 20 days to facilitate a comprehensive evaluation of their stability in suspension. The assessment involved a multifaceted approach, encompassing rheological analysis, scrutiny of turbidity, sedimentation assessment, ζ-potential, and measurement of particle size. The findings from these observations revealed that SDH exhibits a dilatant behavior when in solution, signifying an increase in with higher shear rate. Furthermore, it demonstrates commendable stability when stored under ambient conditions. SDH is emerging as a potential alternative stabilizer for use in aqueous solutions due to its easy extraction and application.

RESUMO

Nanoencapsulation of native potato bioactive compounds by spray-drying improves their stability and bioavailability. The joint effect of the inlet temperature and the ratio of the encapsulant (quinoa starch/gum arabic) on the properties of the nanocapsules is unknown. The purpose of this study was to determine the best conditions for the nanoencapsulation of these compounds. The effects of two inlet temperatures (96 and 116 °C) and two ratios of the encapsulant (15 and 25% w/v) were evaluated using a factorial design during the spray-drying of native potato phenolic extracts. During the study, measurements of phenolic compounds, flavonoids, anthocyanins, antioxidant capacity, and various physical and structural properties were carried out. Higher inlet temperatures increased bioactive compounds and antioxidant capacity. However, a higher concentration of the encapsulant caused the dilution of polyphenols and anthocyanins. Instrumental analyses confirmed the effective encapsulation of the nuclei in the wall materials. Both factors, inlet temperature, and the encapsulant ratio, reduced the nanocapsules' humidity and water activity. Finally, the ideal conditions for the nanoencapsulation of native potato bioactive compounds were determined to be an inlet temperature of 116 °C and an encapsulant ratio of 15% w/v. The nanocapsules obtained show potential for application in the food industry.

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Iron deficiency leads to ferropenic anemia in humans. This study aimed to encapsulate iron-rich ovine and bovine erythrocytes using tara gum and native potato starch as matrices. Solutions containing 20% erythrocytes and different proportions of encapsulants (5, 10, and 20%) were used, followed by spray drying at 120 and 140 °C. Iron content in erythrocytes ranged between 2.24 and 2.52 mg of Fe/g; microcapsules ranged from 1.54 to 2.02 mg of Fe/g. Yields varied from 50.55 to 63.40%, and temperature and encapsulant proportion affected moisture and water activity. Various red hues, sizes, and shapes were observed in the microcapsules. SEM-EDS analysis revealed the surface presence of iron in microcapsules with openings on their exterior, along with a negative zeta potential. Thermal and infrared analyses confirmed core encapsulation within the matrices. Iron release varied between 92.30 and 93.13% at 120 min. Finally, the most effective treatments were those with higher encapsulant percentages and dried at elevated temperatures, which could enable their utilization in functional food fortification to combat anemia in developing countries.

RESUMO

Native potato clones grown in Peru contain bioactive compounds beneficial to human health. This study aimed to optimize the spray-drying nanoencapsulation of native potato phenolic extracts utilizing a central composite design and response surface methodology, obtaining the optimal treatment to an inlet temperature of 120 °C and an airflow of 141 L/h in the nano spray dryer B-90, which allowed maximizing the yield of encapsulation, antioxidant capacity (DPPH), encapsulation efficiency (EE), total phenolic compounds, and total flavonoids; on the other hand, it allowed minimizing hygroscopicity, water activity (Aw), and moisture. Instrumental characterization of the nanocapsules was also carried out, observing a gain in lightness, reddening of the color, and spherical nanoparticles of heterogeneous size (133.09-165.13 nm) with a negative ζ potential. Thermal, infrared, and morphological analyses confirmed the encapsulation of the core in the wall materials. Furthermore, an in vitro release study of phenolic compounds in an aqueous solution achieved a maximum value of 9.86 mg GAE/g after 12 h. Finally, the obtained nanocapsules could be used in the food and pharmaceutical industry.

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RESUMO

Native potatoes (Solanum tuberosum spp. andigena) have diverse pigments and are cultivated in Peru's high Andean regions; they are characterized by containing bioactive compounds that prevent various degenerative diseases. The study aimed to evaluate the physicochemical and sensory quality in chips of native potato clones grown at 3496 m altitude, for which the potatoes were cut into slices and fried in extra virgin olive oil at 180 °C for 200 s. This was determined by proximal analysis, reducing sugars, minerals, color, antioxidant capacity (AC), total phenolic compounds (TPC), and anthocyanins in fresh and chips; an instrumental characterization by FTIR and SEM and sensory tests were also performed. The native potatoes presented low moisture and reduced sugar contents; when frying, their bioactive properties improved, increasing AC, TPC, and trace elements, such as K, Mg, Ca, P, Fe, and Zn. To conclude, fresh clones have high yields in the field and are an essential source of nutrients and bioactive; the salt-free chips of clone B presented better physicochemical properties and greater sensory acceptance, closely followed by clone A. Both clones could be used as raw material by food companies that produce snacks to benefit high Andean agricultural producers.