Starch-based films affected by the addition of collagen from Prochilodus magdalenae residues and HPMC: Application in Andean blackberry (Rubus glaucus Benth) coatings.

Starch-based films offer the advantages of biodegradability, edibility, barrier properties, flexibility, and adaptability. This study compared the physicochemical properties of starch-based films by adding raw fish collagen and hydroxypropylmethylcellulose (HPMC). The tensile properties were evaluated, and the interaction with water was analyzed. Barrier properties, such as water vapor and oxygen permeability, were examined, and optical properties, such as gloss and good internal transmittance, were evaluated. The films were evaluated as coatings on Andean blackberries (Rubus glaucus Benth) for 2 weeks at 85% RH and 25°C. The results showed that the inclusion of collagen caused a reduction in the tensile strength and elastic modulus of the films. Also, the formulation with the highest collagen concentration (F7) exhibited the lowest weight loss and water vapor permeability, also it had the highest collagen concentration and showed the highest reduction in Xw and WAC, with values of 0.048 and 0.65 g water/g dry film, respectively. According to analyzing the optical properties, F1 presented the highest bright-ness and transmittance values, with 18GU and 82 nm values, respectively. In general, the films and coatings are alternatives to traditional packaging materials to prolong the shelf life of these fruits.

Development of films based on chitosan, gelatin and collagen extracted from bocachico scales (Prochilodus magdalenae).

Biodegradable biopolymers from species of the animal kingdom or their byproducts are sustainable as ecological materials due to their abundant supply and compatibility with the environment. The research aims to obtain a biodegradable active material from chitosan, gelatin, and collagen from bocachico scales (Prochilodus magdalenae). Regarding the methodology, films were developed from gelatin, chitosan, and collagen from bocachico scales (Prochilodus magdalenae) at different concentrations using glycerol as a plasticizer and citric acid as a cross-linker. The films were obtained with the hydrated mass processed by compression molding and characterized according to humidity, water solubility, contact angle, mechanical properties, and structural properties. The results of the films showed a hydrophobic characteristic. First, the chitosan-collagen (CS/CO) films showed a yellowish color, while the gelatin-collagen (Gel/CO) films were transparent and less soluble than the gelatin-collagen (Gel/CO) films. Concerning mechanical properties, gelatin films showed higher stiffness and tensile strength than chitosan films. Furthermore, in the morphological analysis, more homogeneous chitosan films were obtained by increasing the concentration of citric acid. In general, chitosan, gelatin, and collagen extracted from the scales of the bocachico (Prochilodus magdalenae) are an alternative in the application of films in the food industry.

Evaluation of the Reactivity of Methanol and Hydrogen Sulfide Residues with the Ziegler-Natta Catalyst during Polypropylene Synthesis and Its Effects on Polymer Properties.

The study focused on the evaluation of the influence of inhibitory compounds such as hydrogen sulfide (H2S) and methanol (CH3OH) on the catalytic productivity and properties of the polymers in the polymerization process with the Ziegler-Natta catalyst. The investigation involved experimental measurements, computational calculations using DFT, and analysis of various parameters, such as molecular weight, melt flow index, xylene solubility, and reactivity descriptors. The results revealed a clear correlation between the concentration of H2S and methanol and the parameters evaluated. Increasing the H2S concentrations, on average by 0.5 and 1.0 ppm, resulted in a drastic decrease in the polymer's molecular weight. A directly proportional relationship was observed between the flow rate and the H2S concentration. In the case of methanol, the change occurred from 60 ppm, causing a sharp decrease in the molecular weight of the polymer, which translates into an increase in the fluidity index and a decrease in solubility in xylene. The presence of these inhibitors also affected the catalytic activity, causing a reduction in the productivity of the Ziegler-Natta catalyst. Computational calculations provided a deeper understanding of the molecular behavior and reactivity of the studied compounds. The computational calculations yielded significantly lower results compared to other studies, with values of -69.0 and -43.9 kcal/mol for the Ti-CH3OH and H2S interactions, respectively. These results indicate remarkable stability in the studied interactions and suggest that both adsorptions are highly favorable.

Optimization of fluidized bed agglomeration process for developing a blackberry powder mixture.

The research objective was to experimentally optimize the fluidized bed agglomeration process of an agglomerated blackberry powder mixture (ABPM) using the response surface methodology. As a raw material, a powdered mixture of blackberry from Castile (Rubus glaucus Benth) obtained by spray drying (SD) was used. In the evaluation of the agglomeration process, the response surface methodology was applied using a central design with a face-centered composition (α = 1), considering the independent variables: fluidisation air inlet temperature (T) (50-70 °C), the binder solution atomization air pressure (P) (1-2 bar) and process time (t) (20-35 min); and the dependent variable: moisture content (Xw), solubility (S), wettability (We), apparent density (ρa), total phenols (TP), radical scavenging (ABTS·+ and DPPH· methods), anthocyanins (Ant) (cyanidin-3-glucoside (C3G)), ellagic acid (EA) and vitamin C (Vit. C). In general, the ABPM exhibited higher porosity and particle size, which generated changes in S, We and ρa, and a better rehydration capacity of the ABPM. The optimal process conditions (T = 70 °C, P = 1.7 bar and t = 21.7 min) defined the most favourable attributes of the ABPM (Xw = 9.7 ± 0.1%, S = 74.9 ± 4.9%, We = 13.7 ± 3.6 min, ρa = 0.312 ± 0.009 g/mL, TP = 4084.6 ± 30.6 mg AGE/100g dry base (db), ABTS·+ = 4511.4 ± 124.5 mg TE/100 g db, DPPH· = 4182.7 ± 66.4 mg TE/100 g db, Ant = 213.6 ± 15.9 mg C3G/100 g db, EA = 1878.2 ± 45.9 mg/100 g db and Vit. C = 29.8 ± 7.4 mg/100 g db. The agglomeration process improved the instantaneous properties and the flow behaviour of the ABPM. Additionally, it offers significant nutritional value with potential use as an instant drink and raw material for the food industry.

Parts per Million of Propanol and Arsine as Responsible for the Poisoning of the Propylene Polymerization Reaction.

Polypropylene synthesis is a critical process in the plastics industry, where control of catalytic activity is essential to ensure the quality and performance of the final product. In this study, the effect of two inhibitors, propanol and arsine, on the properties of synthesized polypropylene was investigated. Experiments were conducted using a conventional catalyst to polymerize propylene, and different concentrations of propanol and arsine were incorporated into the process. The results revealed that the addition of propanol led to a significant decrease in the Melt Flow Index (MFI) of the resulting polypropylene. The reduction in the MFI was most notable at a concentration of 62.33 ppm propanol, suggesting that propanol acts as an effective inhibitor by slowing down the polymerization rate and thus reducing the fluidity of the molten polypropylene. On the other hand, introducing arsine as an inhibitor increased the MFI of polypropylene. The maximum increase in the MFI was observed at a concentration of 0.035 ppm arsine. This suggests that small amounts of arsine affect the MFI and Mw of the produced PP. Regarding the catalyst productivity, it was found that as the concentration of propanol in the sample increased (approximately seven ppm), there was a decrease in productivity from 45 TM/kg to 44 TM/kg. Starting from 10 ppm, productivity continued to decline, reaching its lowest point at 52 ppm, with only 35 MT/kg. In the case of arsine, changes in catalyst productivity were observed at lower concentrations than with propanol. Starting from about 0.006 ppm, productivity decreased, reaching 39 MT/kg at a concentration of 0.024 ppm and further decreasing to 36 TM/kg with 0.0036 ppm. Computational analysis supported the experimental findings, indicating that arsine adsorbs more stably to the catalyst with an energy of -60.8 Kcal/mol, compared to propanol (-46.17 Kcal/mol) and isobutyl (-33.13 Kcal/mol). Analyses of HOMO and LUMO orbitals, as well as reactivity descriptors, such as electronegativity, chemical potential, and nucleophilicity, shed light on the potential interactions and chemical reactions involving inhibitors. Generated maps of molecular electrostatic potential (MEP) illustrated the charge distribution within the studied molecules, further contributing to the understanding of their reactivity. The computational results supported the experimental findings and provided additional information on the molecular interactions between the inhibitors and the catalyst, shedding light on the possible modes of inhibition. Solubles in xylene values indicate that both propanol and arsine affect the polymer's morphology, which may have significant implications for its properties and final applications.

Dimethylformamide Impurities as Propylene Polymerization Inhibitor.

This research study examined how the use of dimethylformamide (DMF) as an inhibitor affects the propylene polymerization process when using a Ziegler-Natta catalyst. Several experiments were carried out using TiCl4/MgCl2 as a catalyst, aluminum trialkyl as a cocatalyst, and different amounts of DMF. Then, we analyzed how DMF influences other aspects of the process, such as catalyst activity, molecular weight, and the number of branches in the polymer chains obtained, using experimental and computational methods. The results revealed that as the DMF/Ti ratio increases, the catalyst activity decreases. From a concentration of 5.11 ppm of DMF, a decrease in catalyst activity was observed, ranging from 45 TM/Kg to 44 TM/Kg. When the DMF concentration was increased to 40.23 ppm, the catalyst activity decreased to 43 TM/Kg, and with 75.32 ppm, it dropped even further to 39 TM/Kg. The highest concentration of DMF evaluated, 89.92 ppm, resulted in a catalyst productivity of 36.5 TM/Kg and lost productivity of 22%. In addition, significant changes in the polymer's melt flow index (MFI) were noted as the DMF concentration increased. When 89.92 ppm of DMF was added, the MFI loss was 75%, indicating a higher flowability of the polymer. In this study, it was found that dimethylformamide (DMF) exhibits a strong affinity for the titanium center of a Ziegler-Natta (ZN) catalyst, with an adsorption energy (Ead) of approximately -46.157 kcal/mol, indicating a robust interaction. This affinity is significantly higher compared to propylene, which has an Ead of approximately -5.2 kcal/mol. The study also revealed that the energy gap between the highest occupied molecular orbital (HOMO) of DMF and the lowest unoccupied molecular orbital (SOMO) of the Ziegler-Natta (ZN) catalyst is energetically favorable, with a value of approximately 0.311 eV.

A New Route of Valorization of Petrochemical Wastewater: Recovery of 1,3,5-Tris (4-tert-butyl-3-hydroxy-2,6-dimethyl benzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione (Cyanox 1790) and Its Subsequent Application in a PP Matrix to Improve Its Thermal Stability.

The various chemicals in industrial wastewater can be beneficial for improving its circularity. If extraction methods are used to capture valuable components from the wastewater and then recirculate them throughout the process, the potential of the wastewater can be fully exploited. In this study, wastewater produced after the polypropylene deodorization process was evaluated. These waters remove the remains of the additives used to create the resin. With this recovery, contamination of the water bodies is avoided, and the polymer production process becomes more circular. The phenolic component was recovered by solid-phase extraction and HPLC, with a recovery rate of over 95%. FTIR and DSC were used to evaluate the purity of the extracted compound. After the phenolic compound was applied to the resin and its thermal stability was analyzed via TGA, the compound's efficacy was finally determined. The results showed that the recovered additive improves the thermal qualities of the material.

Theoretical-Experimental Study of the Action of Trace Amounts of Formaldehyde, Propionaldehyde, and Butyraldehyde as Inhibitors of the Ziegler-Natta Catalyst and the Synthesis of an Ethylene-Propylene Copolymer.

The copolymer synthesis process can be affected by failures in the production process or by contaminating compounds such as ketones, thiols, and gases, among others. These impurities act as an inhibiting agent of the Ziegler-Natta (ZN) catalyst affecting its productivity and disturbing the polymerization reaction. In this work, the effect of formaldehyde, propionaldehyde, and butyraldehyde on the ZN catalyst and the way in which it affects the final properties of the ethylene-propylene copolymer is presented by analyzing 30 samples with different concentrations of the mentioned aldehydes along with three control samples. It was determined that the presence of formaldehyde 26 ppm, propionaldehyde 65.2 ppm, and butyraldehyde 181.2 ppm considerably affect the productivity levels of the ZN catalyst; this effect increases as the concentration of aldehydes is higher in the process; likewise, these impurities affect the properties of the final product, such as the fluidity index (MFI), thermogravimetric analysis (TGA), bending, tension, and impact, which leads to a polymer with low-quality standards and less resistance to breakage. The computational analysis showed that the complexes formed by formaldehyde, propionaldehyde, and butyraldehyde with the active center of the catalyst are more stable than those obtained by the ethylene-Ti and propylene-Ti complexes, presenting values of -40.5, -47.22, -47.5, -5.2 and -1.3 kcal mol-1 respectively.

Active Films Based on Starch and Wheat Gluten (Triticum vulgare) for Shelf-Life Extension of Carrots.

The use of biodegradable biopolymers with the incorporation of active ingredients has been considered as an alternative to extend the useful life of food. Therefore, the objective of this research was to develop active films based on starch and wheat gluten, containing cinnamon and turmeric essential oils by using the solvent casting method. Different film formulations were made from wheat starch, gluten, glycerol, and essential oils of cinnamon and turmeric. The films were characterized according to their morphology, optical, thermal, antioxidant, and barrier properties. Subsequently, the active properties on baby carrots regarding weight loss, appearance, and fungal growth were evaluated. The results indicated that the starch-based films showed a slight decrease in moisture content with the addition of essential oils (up to 13.29%), but at the same time showed a significant reduction in water solubility (up to 28.4%). Gluten-based films did not present significant differences in these parameters, although the solubility in water tended to increase (up to 13.15%) with the addition of essential oils. In general, the films presented good thermal stability and antioxidant capacity, and in the carrot coating test, a decrease in weight loss of up to 44.44% and 43.33% was observed for the coatings based on starch and gluten with the addition of turmeric essential oil, respectively. Finally, films developed with cinnamon and turmeric essential oils are potential candidates for the design of biodegradable active packaging.

Supercritical CO2 Impregnation of Thymol in Thermoplastic Starch-Based Blends: Chemico-Physical Properties and Release Kinetics.

The aim of the present study was to investigate starch-based materials, prepared in an environmentally friendly way and from renewable resources, suitable for the development of biodegradable active food packaging. For this purpose, a bioactive compound (thymol) was incorporated into thermoplastic starch (TPS) and a TPS blend with poly (ε-caprolactone) (TPS-PCL) by the supercritical CO2 (scCO2) impregnation process. Impregnation experiments with scCO2 were carried out at a pressure of 30 MPa and temperatures in the range of 40-100 °C during 1 to 20 h. The structural, morphological, and thermal properties of the obtained materials were comprehensively evaluated. Bioactive component release kinetic studies were performed in water at 6 °C and 25 °C. It was shown that the scCO2 impregnation process could be successfully employed for thymol loading into TPS and TPS-PCL. The process was significantly influenced by the operating temperature and time as well as content of PCL. The samples showed a controlled release of thymol within seven days with a higher amount of released thymol from the TPS-PCL blend. The obtained materials are solvent-free and release the bioactive component in a controlled manner.

Effect of the Addition of High-Protein Hydrolyzed Flour from Oncorhynchus mykiss Byproducts on the Properties of an Extruded Feed.

This work aims to evaluate the effect of the addition of a high-protein hydrolyzed (HPH) flour from the chemical silage of trout (Oncorhynchus mykiss) residues on the parameters of the extrusion system physicochemical transformations and the microstructure of the extrudate. During the extrusion process, the materials used for the study were the HPH flour obtained from trout by chemical silage, fishmeal, and cassava starch. The extrudate's microstructural changes were evaluated by determining the porosity, scanning electron microscopy, the chemical changes, the amino acid profile, residual formic and lactic acid content, the molecular mass profile, the grade of hydrolysis, and in vitro digestibility. The results showed pellets with high durability due to the cohesiveness of the hydrolyzed protein flour but at the same time with low hardness due to the high porosity achieved. The monitoring carried out to the changes in the protein, such as the degree of hydrolysis, water-soluble protein, and molecular mass profile, verify the binding effect of the high-protein hydrolyzed flour during the extrusion process. Finally, the high-resolution optical microscopy methodology presented a high correlation with the phenomena presented in the experiment.

Epoxidised sesame oil as a biobased coupling agent and plasticiser in polylactic acid/thermoplastic yam starch blends.

This work aims to improve the physicochemical properties of polylactic acid (PLA) and thermoplastic yam starch (TPS) blends using epoxidised sesame oil (ESO). We used epoxidised sesame oil from two Colombian Caribbean crops: Dioscorea rotundata and Sesamum indicum, with an oil substitution of 58.4 %. Films were obtained through extrusion and compression moulding processes. Moisture content, solubility, contact angle, and mechanical, barrier, and structural properties were determined using optical and scanning electron microscopy, infrared Fourier transform spectroscopy. Thermal analyses were also performed using thermogravimetry and differential scanning calorimetry techniques. The results suggest that the PLA and TPS interactions can be improved with the addition of ESO as coupling agent, enhancing the interfacial adhesion between the polymers, and favouring the smoothness of the film surface. Furthermore, the ESO addition led to increased thermal stability while restricting molecular mobility, indicating a coupling agent effect. In conclusion, the use of epoxidised oil for preparing films based on high PLA content and TPS allows obtaining enhanced interfacial adhesion. Considering the above, the developed materials have potential application in semi-rigid food packaging.

Design and Application of Hydrocolloids from Butternut Squash (Cucurbita moschata) Epidermis as a Food Additive in Mayonnaise-type Sauces.

Hydrocolloids play a fundamental role in the design of new food products in their structure and functionality due to the interaction with the components of complex food matrices; for this reason, natural sources that are friendly to the environment must be sought for their extraction. A microstructure product such as mayonnaise is an oil-in-water-type emulsion design with the components of the complex varying from egg yolk, additives, spices, sugar, and other optional ingredients to improve its stabilities and organoleptic characteristics. The main objective of the study was to design and characterize the physicochemical, bromatological, and sensory analyses and rheological properties of the mayonnaise-type sauce formulated with hydrocolloids obtained from the epidermis of butternut squash (Cucurbita moschata) and xanthan gum. The rheological study allowed us to obtain a behavior of a non-Newtonian flow of the shear-thinning type for all the samples, and flow curves could be well described by the Carreau model (R 2 ≥ 0.993). The samples exhibit a more elastic than viscous behavior, with a higher storage modulus than the loss modulus (G' > G″) in the evaluated frequency range. When performing the physicochemical analysis, pH values (4.02-4.28), titratable acidity (0.40-0.48), peroxide index (12.5-20 meq), and a stable behavior were achieved in all the formulations except for MS2, which showed instability. Regarding the sensory evaluation, the MS3 sample reflected the closest values to the control sample, with a higher level of satisfaction. On the other hand, the bromatological analysis of MS3 presented a humidity value of 55.3 ± 0.27; carbohydrates, 7.66 ± 0.42; protein, 0.87 ± 0.02; fiber, 0.94 ± 0.05; and ash, 0.54 ± 0.05. The development of this product contributes to the transformation and agro-industrial use of the butternut squash (C. moschata); likewise, it allows us to obtain a mayonnaise-type sauce with organoleptic and nutritional characteristics for human consumption.

Development and evaluation of edible films based on cassava starch, whey protein, and bees wax.

Films and edible coatings based on biopolymers have been developed as a packaging, which can be obtained from biodegradable materials and have properties similar to common plastics. These edible materials have many applications in the food industry, preventing mass transfer between the product and the surrounding environment. The objective of this study was to develop and evaluate the physicochemical and mechanical properties of edible films based on cassava starch (CS), whey protein (WP), and beeswax (BW). Response surface methodology has been used and the experiments were carried out based on face-centred composite design. On the other hand, three CS-based controls were formulated to evaluate the effect of the inclusion of WP and BW. The optimization of multiple responses established the optimal formulation: CS (3.17 %), WP (1.30 %), BW (0.50 %), presenting the following response variables: tensile stress (1.92 MPa), elongation (40.4 %), Young's modulus (42.1 MPa), water vapor permeability 1.79 × 10-11 (g mm/s cm2 Pa), swelling capacity (300.3 %), thickness (0.128 mm), moisture content (6.74 %), and colour: lightness (89.9), chromaticity a∗ (-1.8), chromaticity b∗ (7.7), saturation (9.9), tone (101.1°), and yellowness index (17.7). The selection and evaluation of this optimal formulation are essential because it is the material that shows the best possible mechanical and physicochemical properties using the studied components. The results, especially its good mechanical properties and low permeability to water vapour, would allow its application as a coating for fruits, vegetables, among others, effectively delaying its weight loss due to dehydration.

Effect of a multifunctional edible coating based on cassava starch on the shelf life of Andean blackberry.

The blackberry is a fragile fruit with a high degree of decomposition, which limits its shelf life. The effect of an edible coating (EC) based on cassava starch, whey protein, beeswax, chitosan, glycerol, stearic acid, and glacial acetic acid on the shelf life of fruit stored at 4 °C was evaluated. The physical, chemical, physical, microbiological, and sensorial quality was evaluated, comparing with a fresh control fruit. The EC had a positive effect on the physicochemical and sensorial properties (mainly in texture, flavor, and aromas), due to the reduction of physiological processes, whereas the color changes are mainly due to anthocyanin losses. After 10 days of storage, weight losses were 39.6% lower and firmness was 81.4% higher; while chitosan reduced the mold and yeast count. The EC increased the useful life of the Andean blackberries by 100%.

Extracción y encapsulación de compuestos fenólicos provenientes de cascarilla de arroz / Extraction and encapsulation of phenolic compounds from rice hus

RESUMEN En la actualidad, el aprovechamiento de los subproductos agroindustriales es de vital importancia. El objetivo del presente trabajo fue estudiar una alternativa de valorización de la cascarilla de arroz, mediante la extracción y la encapsulación de compuestos fenólicos provenientes de las cascarillas. Este proceso fue llevado a cabo en un reactor batch con agitación mecánica a 453,15 K y 1 MPa durante 1 h, se usó agua como solvente. Se evaluó la micro-encapsulación de los componentes del extracto mediante liofilización usando como material encapsulante maltodextrina en diferentes proporciones. Los extractos acuosos mostraron un pH de 3,7, contenido de compuestos fenólicos de 8,2 mg equivalentes de ácido gálico/g de cascarilla, y una actividad antioxidante de 14,6 mg Eq.trolox/g de cascarilla. Mediante análisis de espectroscopía de infrarrojo se identificaron bandas representativas de grupos funcionales presentes en los compuestos fenólicos, reconocidos por su actividad antioxidante. La eficiencia de encapsulación fue de 99,8 % usando 14,3 % de maltodextrina, se obtuvieron cápsulas con 10,08 mg fenoles/g de encapsulado y un tamaño de partícula adecuado para la liberación y retención de los compuestos fenólicos de 63 μm. Posteriormente, se estudió la estructura semicristalina de las cápsulas mediante difracción de rayos X. Como conclusión, estas microcápsulas antioxidantes pueden ser adecuadas para su utilización en la industria farmacéutica o de alimentos como componente de envases alimentarios.

SUMMARY Currently, the use of agro-industrial by-products is of vital importance. The aim of the present work was to study an alternative of valorisation of the rice husk, by extraction and encapsulation of phenolic compounds from the husks. This process was carried out in a batch reactor with mechanical stirring at 453.15 K and 1 MPa for 1 h, water was used as the solvent. Microencapsulation of the extract components was evaluated by lyophilisation using maltodextrin at different proportions as encapsulating material. The aqueous extracts showed a pH of 3.7, contained phenolic compounds of 8.2 mg gallic acid/g of husk, and an antioxidant activity of 14.6 mg Eq.trolox/g of husk. By infrared spectroscopy analysis, representative bands of functional groups present in the phenolic compounds, recognised for their antioxidant activity, were identified. The encapsulation efficiency was 99.8 % using 14.3 % maltodextrin; capsules were obtained with 10.08 mg phenols/g capsules and a particle size suitable for the release and retention of phenolic compounds of 63 μm. Subsequently, the semi-crystalline structure of the capsules was studied by X-ray diffraction. To conclude, these antioxidant microcapsules may be suitable for use in the pharmaceutical or food industry as a component of food packaging.

Efecto del almacenamiento sobre uchuva adicionada con componentes fisiológicamente activos y deshidratada por aire caliente / Effect of storage of hot dried cape gooseberry added with physiologically active components by vacuum impregantion

RESUMEN El objetivo de la investigación fue evaluar el efecto de la temperatura (4, 20 y 30°C), tiempo (0, 1, 2, 3, 4, 5 y 6 meses) y las condiciones del empacado (con y sin vacío), durante el almacenamiento de uchuvas adicionadas por impregnación al vacío con calcio y vitaminas B9, C, D3, E y deshidratadas por aire, a 60°C y 2m/s. El efecto del empacado no fue un factor crítico en la estabilidad de los componentes fisiológicamente activos (CFA). El calcio fue estable a las condiciones de almacenamiento evaluadas. Las vitaminas B9, C y D3 disminuyen con el incremento del tiempo y la temperatura de almacenamiento, mientras que la vitamina E presenta degradación. Las mejores condiciones de almacenamiento durante los 6 meses fueron 4ºC y empacado atmosférico, alcanzando valores de 434,0 ± 45,0mg; 179,1 ± 89,2µg; 28,3 5,4mg; 3,5 ± 1,1µg y 8,7 ± 1,2mg, para Ca y vitaminas B9, C, D3 y E, respectivamente, cumpliendo con el descriptor "Excelente fuente", en todos los nutrientes evaluados, en una porción de 100g, según la normativa colombiana. La técnica de impregnación a vacío es un pretratamiento efectivo para la incorporación de CFA, contribuyendo en la generación de valor de la agrocadena de uchuva.

ABSTRACT The aim of the research was to evaluate the effect of temperature (4, 20 and 30°C), time (0, 1, 2, 3, 4, 5 and 6 months) and the packaging conditions (with and without vacuum), during the storage of gooseberries added with calcium and vitamins B9, C, D3, E by means of vacuum impregnation and then dehydrated by air at 60°C and 2 m/s. The effect of the packing was not a critical factor in the stability of the physiologically active components (PAC). The calcium was stable at the storage conditions evaluated. Vitamins B9, C and D3 decreased with increasing storage time and temperature; whereas, vitamin E showed degradation. The best storage conditions during the 6 months were 4ºC and atmospheric packing, reaching values of 434,0 ± 45,0mg; 179,1 ± 89,2mg; 28,3 ± 5,4mg; 3,5 ± 1,1g y 8,7 ± 1,2mg for calcium and vitamins B9, C, D3 y E respectively, complying with the descriptor "Excellent source" in all evaluated nutrients in a portion of 100g according to the Colombian regulations. The technique of vacuum impregnation is an effective pretreatment for the incorporation of PAC, contributing to the generation of value of the cape gooseberry agrochain.

Isolation and characterisation of microcrystalline cellulose and cellulose nanocrystals from coffee husk and comparative study with rice husk.

Cellulosic material from coffee husk has not been previously studied despite being a potential source of reinforcing agents for different applications. This material has been extracted and characterised from coffee husk, in parallel with previously studied rice husk. Samples have been analysed as to their ability to obtain cellulosic fibres and cellulose nanocrystals (CNC) by applying alkali and bleaching treatments and final sulphuric acid hydrolysis. Microstructural changes were analysed after treatments, and the size and aspect ratio of CNCs were determined. Crystallinity and thermal stability of both materials progressed in line with the enrichment in cellulosic compounds. The CNC aspect ratio was higher than 10, which confers good reinforcing properties. These were tested in thermoplastic starch films, whose elastic modulus increased by 186 and 121% when 1 wt% of CNCs from rice and coffee husks, respectively, was incorporated into the matrix. Coffee husk represents an interesting source of cellulosic reinforcing materials.

Enhancement of interfacial adhesion between starch and grafted poly(ε-caprolactone).

The use of a modified poly(ε-caprolactone) (gPCL) to enhance polymer miscibility in films based on thermoplastic starch (S) and poly(ε-caprolactone) is reported. PCL was functionalized by grafting with maleic anyhdride (MA) and/or glycidyl methacrylate (GMA) by reactive blending in a batch mixer. gPCL based materials were analysed in terms of their grafting degree, structural and thermal properties. Blends based on starch and PCL (wt. ratio 80:20) with including gPCL (0, 2.5 and 5wt.%), as a compatibilizer, were obtained by extrusion and compression moulding, and their structural, thermal, mechanical and barrier properties were investigated. Blends containing gPCL evidenced better interfacial adhesion between starch and PCL domains, as deduced from both structural (XRD, FTIR, SEM) and bulk properties (DSC, TGA). Moreover, grafted PCL-based compatibilizers greatly improved functional properties of S-PCL blend films, as pointed out from mechanical performance and higher barrier properties, valuable to meet the food packaging requirements.

Active bilayer films of thermoplastic starch and polycaprolactone obtained by compression molding.

Bilayer films consisting of one layer of PCL with either one of thermoplastic starch (S) or one of thermoplastic starch with 5% PCL (S95) were obtained by compression molding. Before compression, aqueous solutions of ascorbic acid or potassium sorbate were sprayed onto the S or S95 layers in order to plasticize them and favor layer adhesion. S95 films formed bilayers with PCL with very good adhesion and good mechanical performance, especially when potassium sorbate was added at the interface. All bilayers enhanced their barrier properties to water vapour (up to 96% compared to net starch films) and oxygen (up to 99% compared to PCL pure). Bilayers consisting of PCL and starch containing 5% PCL, with potassium sorbate at the interface, showed the best mechanical and barrier properties and interfacial adhesion while having active properties, associated with the antimicrobial action of potassium sorbate.