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-The thermomechanical properties of dough and the physical characteristics of bread from quinoawheat and potato-wheat composite flours at 10 and 20% substitution level were evaluated. The functional properties of flours were measured by the water absorption index (WAI), water solubility index (WSI) and swelling power (SP). The thermomechanical properties of wheat and composite flours were assessed using a Mixolab and the baking quality characteristics of breads were weight, height, width, and specific volume. The results showed that the higher values of WAI (4.48), WSI (7.45%), and SP (4.84) were for potato flour. The quinoa-wheat composite flour presented lower setback and cooking stability data, which are a good indicator of shelf life of bread. On the other hand, the potato-wheat composite flour showed lower stability, minimum torque and peak torque, and higher water absorption. Weight, height, width, and specific volume of wheat bread were most similar to samples of potato-wheat composite flour at 10% substitution level.

The influence of the drying temperature (35 and 45C) on bee pollen is evaluated based on the physical, chemical and nutritional characteristics of dried bee pollen from two zones in Colombia (La Calera and Zipaquira). The methods used to establish the effect of the treatment are: determination of chemical composition, measurement of water activity, solubility index, mean particle size, vitamin C content and carotene content. The results confirm that the drying process of bee pollen at 45C has the shorter drying time (156–198 min), moisture content (7–8%) and water activity (0.3), but higher levels of carotene and vitamin C losses. The protein, fiber and ash contents are not affected by the drying temperature. The observed higher carotene content of the pollen from La Calera is probably because of the flora composition in this zone. The vitamin C content decreases as the drying temperature increases, but there are no significant differences between zones. PRACTICAL APPLICATIONS Bee pollen can be sold as both fresh and dried products. However, refrigeration with temperature between 5 and 10C is required for storage of the fresh bee pollen to preserve quality. The bee pollen drying allows preserving the product at room temperature, making the product marketing easier and increasing the profits of beekeepers. The drying process of bee pollen in Colombia is done by sun, solar and oven‐drying methods. But hot‐air drying is considered as a suitable drying method because it decreases drying time and improves the hygienic quality of the dried product. The chemical, physical and nutritional properties of dried bee pollen were studied in order to evaluate the effect of drying temperature on pollen from different origins. Thus, the results of this investigation can help the apiarists to use the best drying conditions to produce dried bee pollen.

-Orange peel represents approximately 30-40 g/100g of the fresh fruit weight and could be used to develop value-added products. Hence, this study aims to evaluate the effects of drying conditions on the physical properties of orange peel impregnated with sucrose solution. The response surface method (RSM) was used to optimize two parameters: drying temperature (35-55 °C) and air flow rate (2-3 m/s). The measured responses used to determine the effect of dying process conditions were: moisture content. drying time. total soluble solids. color and hardness. The dried orange peels from the optimal process were subjected to a sensory test by 60 consumers. The optimum conditions for the drying of orange peels were determined to obtain minimum hardness, moisture content and drying time for a w values below 0.6. The optimum conditions were found to be a dying temperature of 52.3 °C and air flow rate of 2.0 m/s. At this point, drying time, hardness and moisture content were found to be 20 h, 78.4 N and 7.6%, respectively. The sensory results showed that consumers aged over 30 years old accepted well the dried orange peel.

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 cm 2 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.

The effect of guar gum and a guar gum/hydroxypropyl methylcellulose (HPMC) blend on the pasting profile of a tapioca starch-precooked corn flour mixture was assessed. Moreover, the baking quality characteristics of gluten-free (GF) cheese bread with these hydrocolloids added were evaluated. The properties were weight, height, diameter, specific volume, hardness, dough stickiness, and dough and crumb moisture content. The guar gum increased the peak, breakdown and final viscosities, whereas the guar gum/HPMC blend increased the setback viscosity. The addition of hydrocolloids (guar gum and guar gum/HPMC) decreased the GF dough stickiness. As the concentration of guar gum increased, the hardness of the GF cheese bread decreased. Adding guar gum at levels of 5% w/w based on the amount of cheese prevented increases in the hardness of the GF cheese bread during 6 days of storage and, therefore, might be used to increase the shelf life of this product. PRACTICAL APPLICATIONSThis research would have practical applications in gluten-free (GF) cheese bread in terms of providing technological information about the influence of hydrocolloids on the quality characteristics of this product. Gums and hydrocolloids are essential ingredients in GF bread formulations for improving the texture and the appearance of the final products. In this study, guar gum and a guar gum/ hydroxypropyl methylcellulose blend were used to overcome quality losses and improve the texture properties of GF cheese breads. Adding guar gum at levels of 5% w/w based on the amount of cheese decreased hardness in the GF cheese bread during storage for 6 days at room temperature and, therefore, can assure a longer shelf life.

Background: Colombia is the fifth largest producer of avocado and its agribusiness chain lacks value-added diversified products; therefore, at the governmental level, there has been promotion of internationalization policies aimed at opening up new markets and innovation with improved technology and food consumption patterns. The spray drying is an alternative conservation for avocado, a highly perishable fruit. Objectives: the aim of this study was to optimize the spray drying process for obtaining Hass avocado powder with better physicochemical properties and processing. Methods: an experimental design "Optimal" was used in the response surface methodology based on four factors: (A) maltodextrin (MD) concentration (2.81 to 11.25% w/w), (B) air inlet temperature (140-160°C), (C) outlet air temperature (80-90°C) and (D) atomizer disk speed (20000-26000 rpm). Results: the response variables where statistically significant differences (p<0.05) were found including: moisture, water activity, solubility, color coordinates (L*, a*, b*) hygroscopicity, wettability, extractable oil and deposit formation versus factors studied. Optimized value factors were: (A) 6.93% (B) 160°C (C) 84°C and (D) 26000 rpm. Conclusions: the experimental process optimization is presented as an effective tool for agribusiness, which improves product quality in terms of the factors that affect it, and in the case of avocado, allows the development of new value-added products, with potential uses in the food industry, pharmaceutical, cosmeceutical, among others.

Degradation kinetic parameters in vitamins and antioxidants in coconut powder fortified with functionally active compounds (CP+FAC) during storage represents a valuable tool to predict the product’s shelf life. The aim of this research was to evaluate the degradation kinetics during storage of vitamins (C, D3, and E), total phenols, and properties associated to antioxidant activity. Vitamins were quantified via high-resolution liquid chromatography and the antioxidant activity through DPPH and ABTS free radical scavenging activity. An experimental design was used with two-factor factorial design: 1) storage time (tS) and 2) treatment: temperature (TA) - type of packaging (N2 and atmospheric air), where the dependent variables were adjusted to zero-, first-, and second-order kinetic models. In general, losses of FAC were significant with respect to the factors evaluated and their interactions, with minor changes at lower TA and packaged with N2, indicating that the degradation kinetics of the FAC is slower under these storage conditions. Increased storage temperature reduced FACstability, where the Arrhenius equation was able to quantify the effect of temperature of the rate of deterioration reactions of the FAC.