The pisco industry in Peru generates large amounts of grape pomace, which is a natural source of bioactive compounds with potential nutraceutical applications. Hot pressurized liquid extraction (HPLE) with water-ethanol solvent mixtures (20–60%) at high temperatures (100–160 °C) was applied to recover polyphenols from the skin and seeds of a Peruvian pisco-industry grape-pomace waste. At the same HPLE conditions (60% ethanol, 160 °C), the seed fraction extracts contained ~6 times more total polyphenol and presented ~5 times more antioxidant activity than the extract from the skin fraction. The lowest ethanol concentration (20%) and the highest temperature (160 °C) achieved the highest recovery of flavanols with 163.61 µg/g dw from seeds and 10.37 µg/g dw from skins. The recovery of phenolic acids was maximized at the highest ethanol concentration and temperature with 45.34 µg/g dw from seeds and 6.93 µg/g dw from skins. Flavonols were only recovered from the skin, maximized (17.53 µg/g dw) at 20% of ethanol and the highest temperature. The recovery of specific polyphenols is maximized at specific extraction conditions. These conditions are the same for seed and skin extractions. This alternative method can be used in other agroindustrial wastes in order to recover bioactive compounds with potential applications in the pharmaceutical and food industry.

El estrés académico en estudiantes universitarios asociado a la pandemia COVID-19 está incrementándose debido al cambio de la educación presencial a virtual, causando disminución de motivación y aumento de ansiedad en los estudiantes. El objetivo del presente trabajo, es la evaluación del estrés académico en estudiantes universitarios frente a la educación virtual asociada al COVID-19, para ello se aplicó el cuestionario validado de estrés académico SISCO SV- COVID-19, obteniendo que el 92.27% de estudiantes encuestados tienen estrés académico, identificándose como factor estresor a la sobrecarga de tareas y trabajos que deben cumplir en los plazos establecidos por los docentes.

The use of water–ethanol mixtures in hot pressurized liquid extraction (HPLE) to recover phenolic compounds from agro-industrial waste has been successfully investigated. However, the unresolved challenge of reducing solvent costs associated with the process hinders the scaling of this eco-friendly technology. This study evaluated the use of isopropanol as an alternative, lower-cost solvent for recovering polyphenols from discarded blueberries through the HPLE process. HPLE was carried out using water–isopropanol mixtures (0, 15 and 30%) at 70, 100, and 130 °C. The total polyphenol content (TPC), antioxidant capacity (DPPH and ORAC), glucose and fructose contents, and polyphenol profile of the extracts were determined. HPLE extracts obtained using high isopropanol concentrations (30%) and high temperatures (130 °C) presented the highest TPC (13.57 mg GAE/gdw) and antioxidant capacity (IC50: 9.97 mg/mL, ORAC: 246.47 µmol ET/gdw). Moreover, the use of 30% water–isopropanol resulted in higher yields of polyphenols and removal of reducing sugars compared to atmospheric extraction with water–acetone (60%). The polyphenolic profiles of the extracts showed that flavanols and phenolic acids were more soluble at high concentrations of isopropanol (30%). Contrarily, flavonols and stilbenes were better recovered with 15% isopropanol and pure water. Therefore, isopropanol could be a promising solvent for the selective recovery of different bioactive compounds from discarded blueberries and other agro-industrial residues.

Prickly pear (Opuntia ficus-indica L. Miller) is a natural source of antioxidant compounds that have gained significant attention due to their potential health benefits. This study aims to investigate the effectiveness of pressurized liquid extraction (PLE) and Ultrasound-Assisted Extraction (UAE), combined with water–ethanol mixtures from 0 to 60%, at moderate temperatures between 50 °C to 70 °C to improve the recovery of antioxidant compounds from red peel prickly pear. The recovery of these compounds was affected by solvent composition and temperature for both extraction techniques. Interestingly, the use of pure water at 70 °C during the PLE process allowed the recovery of high concentrations of antioxidant compounds (12.96 mg GAE/g dw, IC_5O: 2.03 mg/mL, ORAC: 625 µmol TE/g dw). On the contrary, when the UAE process was combined with 30% ethanol at 50 °C, the extractability of these compounds (10.52 mg GAE/g dw, IC_5O: 3.09 mg/mL, ORAC: 561.26 µmol TE/g dw) was improved. In addition, different solvent compositions were identified to improve the recovery of specific polyphenols. For PLE, pure water at 70 °C was effective in recovering phenolic acids, flavanols, and flavonols, while the highest concentrations of stilbenes were obtained with 60% ethanol at 70 °C. For UAE, the use of 30% ethanol at 50 °C was more effective in extracting phenolic acids and stilbenes, whereas pure water at 50 °C provided high concentrations of flavanols and flavonols. These results contribute to the development of sustainable and efficient extraction strategies for obtaining antioxidant-rich extracts from prickly pear peel with important applications in functional foods, nutraceuticals, and pharmaceutical industries.

In recent years, the consumption of gluten-free products has increased due to the increasing prevalence of celiac disease and the increased preference for gluten-free diets. This study aimed to make cookies using a mixture of cañihua flour, whey, and potato starch. The use of a Box–Behnken design allowed for flexible ingredient proportions and physicochemical properties, centesimal composition, color, texture, and sensory attributes to be evaluated through consumer tests (Sorting and acceptability). The results highlighted significant variations in physicochemical data, composition, color, and texture across formulations. The blend with 38.51% cañihua flour, 10.91% sweet whey, 25.69% potato starch, 8.34% margarine, 11.10% sugar, 0.19% sodium chloride, 0.51% baking powder, 0.51% vanilla essence, and 4.24% egg exhibited superior sensory appeal. This formulation boasted excellent texture, aroma, flavor, color, and appearance, indicating high sensory and physicochemical quality. The use of cañihua flour, sweet whey, and potato starch not only provides a gluten-free option but also delivers a nutritious and sensorily pleasing choice for those with dietary restrictions. Future research could explore the commercial viability of producing these cookies on a larger scale, as well as investigating the potential health benefits of these ingredients.

This study aimed to extract and characterize the morphological, physicochemical, thermal, and rheological properties of the starches of native potatoes grown in the department of Puno. Among the varieties evaluated were sweet native potato varieties Imilla Negra (Solanum tuberosum spp. Andígena), Imilla Blanca (Solanum tuberosum spp. Andígena), Peruanita, Albina or Lomo (Solanum chaucha), and Sutamari, and the bitter potatoes Rucki or Luki (Solanum juzepczukii Buk), Locka (Solanum curtilobum), Piñaza (Solanum curtilobum), and Ocucuri (Sola-num curtilobum), acquired from the National Institute of Agrarian Innovation (INIA-Puno). The proximal composition, amylose content, and morphological, thermal, and rheological properties that SEM, DSC, and a rheometer determined, respectively, were evaluated, and the data obtained were statistically analyzed using a completely randomized design and then a comparison of means using Tukey’s LSD test. The results show a significant difference in the proximal composition (p ≤ 0.05) concerning moisture content, proteins, fat, ash, and carbohydrates. Thus, the amylose content was also determined, ranging from 23.60 ± 0.10 to 30.33 ± 0.15%. The size morphology of the granules is 13.09–47.73 µm; for the thermal and rheological properties of the different varieties of potato starch, it is shown that the gelatinization temperature is in a range of 57 to 62 °C and, for enthalpy, between 3 and 5 J/g.