Effect of the Addition of Corn Husk Cellulose Nanocrystals in the Development of a Novel Edible Film.

The cellulose from agroindustrial waste can be treated and converted into nanocrystals or nanofibers. It could be used to produce biodegradable and edible films, contributing to the circular economy and being environmentally friendly. This research aimed to develop an edible film elaborated with activated cellulose nanocrystals, native potato starch, and glycerin. The activated cellulose nanocrystals were obtained by basic/acid digestion and esterification with citric acid from corn husks. The starch was extracted from the native potato cultivated at 3500 m of altitude. Four film formulations were elaborated with potato starch (2.6 to 4.4%), cellulose nanocrystals (0.0 to 0.12%), and glycerin (3.0 to 4.2%), by thermoforming at 60 °C. It was observed that the cellulose nanocrystals reported an average size of 676.0 nm. The films mainly present hydroxyl, carbonyl, and carboxyl groups that stabilize the polymeric matrix. It was observed that the addition of cellulose nanocrystals in the films significantly increased (p-value < 0.05) water activity (0.409 to 0.447), whiteness index (96.92 to 97.27), and organic carbon content. In opposition to gelatinization temperature (156.7 to 150.1 °C), transparency (6.69 to 6.17), resistance to traction (22.29 to 14.33 N/mm), and solubility in acidic, basic, ethanol, and water media decreased. However, no significant differences were observed in the thermal decomposition of the films evaluated through TGA analysis. The addition of cellulose nanocrystals in the films gives it good mechanical and thermal resistance qualities, with low solubility, making it a potential food-coating material.

Preliminary Characterization of a Spray-Dried Hydrocolloid from a High Andean Algae (Nostoc sphaericum).

The search for new natural sources of hydrocolloids with stabilizing, thickening, and good binding capacity, from raw materials that are environmentally friendly and that contribute to the circular economy is a challenge for the food industry. The aim of the study was the preliminary characterization of a spray-dried hydrocolloid from high Andean algae Nostoc sphaericum. Four ecotypes of algae from Peruvian high Andean lagoons located above 4000 m were considered. The samples were collected in the period March−April 2021 and were subjected to a spray drying process in an aqueous medium. The characterization showed that the dehydrated nostoc ecotypes presented high protein and carbohydrate content, making it a potential material for direct use as a functional food for humans. The spray-dried product presented good stability for its use as a hydrocolloid, with zeta potential values (ζ), around 30 mV, evidencing the presence of -CO-, -OH, -COO-, and -CH groups, characteristic of polysaccharides, representing 40% of total organic carbon on average, giving it low water activity values and particle size at the nanometric level. Major minerals such as Ca (>277 mg/100 g), Mg (>19.7 mg/100 g), and Fe (>7.7 mg/100 g) were reported. Spray-dried nostoc is a hydrocolloid material with high potential for the food industry, with good nutritional content and techno-functional behavior.

Storage Conditions and Adsorption Thermodynamic Properties for Purple Corn.

Adsorption isotherms provide insight into the thermodynamic properties governed by food storage conditions. Adsorption isotherms of purple corn of the Canteño variety were evaluated at 18, 25, and 30 °C, for the equilibrium relative humidity (ERH) range between 0.065 and 0.95. The equilibrium moisture (Xe) was determined by the continuous weight-change method. Seven mathematical models of isotherms were modeled, using the coefficient of determination R2, mean absolute error (MAE), and estimated standard error (ESE) as the convergence criterion. Thermodynamic parameters such as isosteric heat (qst), Gibbs Free Energy (ΔG), differential entropy (ΔS), activation energy (Ea), and compliance with the isokinetic law were evaluated. It was observed that the adsorption isotherms presented cross-linking around 75% ERH and 17% Xe, suggesting adequate storage conditions at these values. The GAB and Halsey models reported better fit (R2 > 97%, MAE < 10%, ESE < 0.014 and random residual dispersion). The reduction of Xe from 17 to 7%, increases qst, from 7.7022 to 0.0165 kJ/g, while ΔG decreases considerably with the increase in Xe, presenting non-spontaneous endergonic behavior, and linear relationship with ΔS, evidencing compliance with the isokinetic theory, governed by qst. Ea showed that more energy is required to remove water molecules from the upper layers bound to the monolayer, evaluated using CGAB. The models predicted the storage conditions, and the thermodynamic parameters show the structural stability of the purple corn grains of the Canteño variety during storage.

Elaboración de snack de maíz chulpi (Zea Maidis L. ) salado sin aceite / Preparation of snack chulpi corn (Zea maidis L. ) oil-free salt

Los alimentos deshidratados siempre han sido utilizados para consume directo en épocas de escasez, sin embargo actualmente están siendo muy utilizados para la formulación de otros tipos de alimentos, ya sea como ingredientes de alimentos funcionales, bocadillos, productos lácteos, desayunos integrales, barras de cereales. No obstante, gran parte de los alimentos deshidratados se deben rehidratar en soluciones determinadas como agua, azucaradas, salinas, entre otras, antes de ser consumidos. Este trabajo presenta la elaboración de un Snack de maíz Chulpi rehidratado con sal, se estudian aspectos como la difusión de una solución de salmuera en el seno del maíz (transferencia de materia), la actividad del agua y se realiza un análisis organoléptico del producto a través de una superficie de respuesta.

Dehydrated food has always been used for direct consumption when food is scarce. However, nowadays this kind of food is being used to formulate other kinds of food, either as ingredients for functional food, snacks, dairy products, wholegrain breakfast, cereal bars. However, most of dehydrated in determined solutions such as water, sweetened water and saline, among others, before being consumed. This work presents the elaboration of a corn Snack Chulpi rehydrated with salt, some aspects are studied as the diffusion of a solution of pickle in the bosom of the corn (transference of matter), the activity of the water and a organoléptico analysis of the product is realized by means of a Surface of answer.