Preparation and characterization of licorice‐chitosan coatings for postharvest treatment of fresh strawberries

Several plant extracts are being investigated to produce edible coatings, mainly due to their antioxidant and antimicrobial activities. In this study, licorice root extracts were produced by ultrasound‐assisted extraction and were combined with chitosan to elaborate edible coatings. Different solvents and temperatures were used in the extraction process, and the antioxidant and antimicrobial activity of the extracts were assessed. The most bioactive extracts were selected for the development of the edible coatings. The rheological properties of the coatings were studied, and they were applied on strawberry to evaluate their physicochemical and microbiological properties. The addition of licorice extract to chitosan resulted in positive effects on the rheological properties of the coatings: the incorporation of phytochemicals to chitosan decreased the shear stress and improved the restructuring ability of the coating solutions. The films presented a reduction of the Burger model parameter, indicating a reduction of rigidity. Furthermore, the strawberry coated with chitosan and licorice extract maintained good quality parameters during storage and showed the best microbiological preservation in comparison with controls. Hence, the use of chitosan with licorice extract is a potential strategy to produce edible coating for improving the postharvest quality of fruitsThis research was funded by Comunidad Autónoma de Madrid, grant number P2013/ABI27, project Bolívar Gana con Ciencia, MinCiencias Contract 368-2019 and Programa Nacional de Innovación Agraria—PNIA of Perú, Contract: No. 152-2018-INIA-PNIA-PASANTI

The effect of storage temperature and time on total phenolics and enzymatic activity of sapodilla (Achras sapota L.)

The tropical fruits are sensitive to low storage temperatures, so optimal parameters have been searched for storage and transport for the purpose of maintaining its overall quality as long as possible to the consumer. The effect of different storage temperatures (6, 10, 15, 21 and 27 ºC) and storage durations (0 to 20 d) on total phenolics and enzymatic activity of peroxidase (POD), catalase (CAT), and polyphenol oxidase (PPO) on sapodilla (Achras sapota L.) fruit was investigated. The extraction and quantitation of protein and phenols from fruit was performed, then the enzymatic activity of PPO, POD and CAT was determined. The concentration of total phenolics decreased in the control fruit. POD activity was 3268.7 ± 1.4 U g-1 in ripening and senescence of sapodilla stored at 27 °C. CAT activity reached a peak of 34.0 ± 0.25 U g-1 in senescence in control fruit. PPO activity remained unchanged in the ripening stage and until consumption. The best storage temperatures to prolong the post-harvest life of the sapodilla fruit were 6 °C and 10 °C when storage was at low temperatures. POD activity was inactivated during sapodilla storage at low temperatures (6 and 10 °C) and after being transferred to 27 °C the activity was reactivated. Likewise of fruits stored at 21 °C after being transferred to 27 °C the POD activity was reactive with a maximum value of 46.3 ± 0.012 U g-1. Enzyme activity decreased at low temperatures, which contributed to the preservation of the fruit, showing that the cold retards the maturation processes

Ultrasound-Assisted Extraction of Mango (<i>Mangifera indica)</i> Kernel Starch: Chemical, Techno-Functional, and Pasting Properties

(1) Background: Starch is the main component of mango (Mangifera indica) kernel, making it an alternative to obtain an ingredient from a non-conventional source with potential application in food and other industrial applications; however, reports on the use of new extraction techniques for this material are scarce. The main objective of this research was to evaluate the effect of ultrasound-assisted extraction (UAE) on the yield, chemical, techno-functional, rheological, and pasting properties of starch isolated from a non-conventional source such as a mango kernel. (2) Methods: Different power sonication conditions (120, 300, and 480 W) and sonication time (10, 20, and 30 min) were evaluated along with a control treatment (extracted by the wet milling method). (3) Results: Ultrasound-assisted extraction increases starch yield, with the highest values (54%) at 480 W and 20 min. A significant increase in the amylose content, water-holding capacity, oil-holding capacity, solubility, and swelling power of ultrasonically extracted starches was observed. Similarly, mango kernel starch (MKS) exhibited interesting antioxidant properties. The sol-gel transition temperature and pasting parameters, such as the breakdown viscosity (BD) and the setback viscosity (SB), decreased with ultrasound application; (4) Conclusion: indicating that ultrasound caused changes in physical, chemical, techno-functional, rheological, and pasting properties, depending on the power and time of sonication, so it can be used as an alternative starch extraction and modification technique, for example, for potential application in thermally processed food products such as baked goods, canned foods, and frozen foods

Food emulsion type oil in water prepared with high-protein from shrimp (Penaeus vannamei) heads flour – SHF

The use of flour from shrimp (Penaeus vannamei) heads with a high content of protein (SHF) to stabilize food emulsions type oil in water (o/w) is an alternative to take advantage of the by-products of the shrimp industry. The aim of this work was to prepare food emulsion type oil in water (o/w) using the SHF due to the high percentage in proteins; for this procedure a physicochemical and bromatological characterization of flour of shrimps (Penaeus vannamei) heads has been done, in which a percentage of protein 51 %, moisture of 11,82 %, fat 8,52 % and 22,23 % of ash has been obtained. The base emulsions may be used in food products such as salad dressing, mayonnaise, spreads, dressings and other products. The different emulsions with adequate rheological and microstructural characteristics were prepared using different concentrations of palm oil (20, 30 and 40%w/w) and different concentrate of SHF (0,5, 1 and 2 % w/w). Therefore, we have obtained a food emulsion stable type oil in water (O/W) with 2 % w/w of SHF, which presented a behavior non-Newtonian fluid type shear-thinning and homogeneous distribution of droplets.El uso de harinas obtenidas a partir de las cabezas de camarones (Penaeus vannamei) - SHF con un altos contenido en proteína para la estabilización de emulsiones alimentarias del tipo de aceite en agua (O/W) son una alternativa para poder aprovechar estos residuos de la industria del camarón. El objetivo de este trabajo fue preparar emulsiones alimentarias aceite en agua (O/W), utilizando la SHF, debido a su alto porcentaje de proteínas. Se realizó la caracterización fisicoquímica y bromatological de la harina SHF, obteniendo unos porcentajes del 51 % en proteína, 11,82 % de humedad, 8,52 % de grasa y 22,23 % de ceniza. Las emulsiones logradas pueden ser utilizadas en productos alimenticios tales como ensaladas, mayonesa, productos para untar, aderezos, entre otros. Se prepararon emulsiones bases con diferentes concentraciones de aceite de palma (20, 30 y 40 % w/w) y de SHF (0,5, 1 y 2 % w/w). A las diferentes emulsiones que presentaron estabilidad se les realizaron las caracterizaciones reológicas y microestructural. Por lo tanto, se obtuvieron emulsiones estables del tipo aceite en agua (O/W) con 2 % w/w de SHF que presenta un comportamiento no newtoniano del tipo reofluidificante y la distribución homogénea de gotitas

Development of Dressing-Type Emulsion with Hydrocolloids from Butternut Squash Seed: Effect of Additives on Emulsion Stability

Background: Natural ingredients have been employed to develop food products. Methods: Hydrocolloids from butternut squash seeds (HBSSs) were extracted with water at pH 3, 7, and 10 and characterized bromatologically and rheologically; then these HBSSs were used to stabilize the dressing-type emulsion by evaluating its physicochemical, rheological, and microstructural properties. Results: Hydrocolloids presented higher protein (from 20.43 to 39.39%) and carbohydrate (from 50.05 to 52.68%) content and rheological properties with a predominant elastic modulus. HBSSs extracted at pH 10 were used for the development of the dressing-type emulsion. The samples were stable during the storage period (15 days), with a good microstructural organization showing non-Newtonian fluid properties with shear-thinning behavior when the pseudoplasticity and the oil droplet size decreased with the addition of HBSS. Conclusions: Hydrocolloid constituents were detected surrounding the droplets of the emulsions, intensifying the effects of inner droplet interaction due to depletion events and a strong influence on the structure and physical stability. The hydrocolloids used to stabilize the dressing-type emulsions are additively promising in microstructured food design

Novel Hydrocolloids Obtained from Mango (Mangifera indica) var. Hilaza: Chemical, Physicochemical, Techno-Functional, and Structural Characteristics

Background: Hydrocolloids are ingredients used to improve the technological properties of products; currently, there is a growing demand from the food industry and consumers to use natural ingredients and reduce the environmental impact. Methods: This work evaluated the effect of pH on hydrocolloid extraction from the pulp, seed, and peel of mango (Mangifera indica) var. hilaza and their chemical, physicochemical, techno-functional, and structural properties. Results: The main component of the hydrocolloid was the carbohydrates for pulp (22.59%) and peel (24.05%), and the protein for seed (21.48%) was corroborated by NIR spectra and associated with the technological and functional properties. The solubility increases with the temperature presenting values higher than 75% at 80 &deg;C; the swelling index was higher than 30%, while the water holding capacity was higher in samples with higher carbohydrate content (110&ndash;121%). Moreover, a higher content of total phenolic compounds (21.61 &plusmn; 0.39&ndash;51.77 &plusmn; 2.48 mg GAE/g) and antioxidant activity (&ge;193.82 &mu;Mol&nbsp;Trolox/g) was obtained. The pH of extraction changes the color parameters and microstructural properties. Conclusions: Novel ingredients from mango pulp, seed, and peel at different pH levels have technological and functional properties that are potential use in the food industry as an alternative to the development of microstructural products

Development of Dressing-Type Emulsion with Hydrocolloids from Butternut Squash Seed: Effect of Additives on Emulsion Stability

Background: Natural ingredients have been employed to develop food products. Methods: Hydrocolloids from butternut squash seeds (HBSSs) were extracted with water at pH 3, 7, and 10 and characterized bromatologically and rheologically; then these HBSSs were used to stabilize the dressing-type emulsion by evaluating its physicochemical, rheological, and microstructural properties. Results: Hydrocolloids presented higher protein (from 20.43 to 39.39%) and carbohydrate (from 50.05 to 52.68%) content and rheological properties with a predominant elastic modulus. HBSSs extracted at pH 10 were used for the development of the dressing-type emulsion. The samples were stable during the storage period (15 days), with a good microstructural organization showing non-Newtonian fluid properties with shear-thinning behavior when the pseudoplasticity and the oil droplet size decreased with the addition of HBSS. Conclusions: Hydrocolloid constituents were detected surrounding the droplets of the emulsions, intensifying the effects of inner droplet interaction due to depletion events and a strong influence on the structure and physical stability. The hydrocolloids used to stabilize the dressing-type emulsions are additively promising in microstructured food design

Physicochemical, Rheological, and Microstructural Properties of Low-Fat Mayonnaise Manufactured with Hydrocolloids from Dioscorea&nbsp;rotundata as a Fat Substitute

(1) Background: In this study, the potential use of Dioscorea rotundata hydrocolloids was evaluated to develop low-fat mayonnaise. (2) Methods: The effect of different concentrations of hydrocolloids on the physicochemical, microstructural, and rheological properties of mayonnaise was evaluated. (3) Results: Physicochemical analyses showed pH values that were stable over time but decreased with increasing hydrocolloid concentration. The color parameters showed a decrease in luminosity and an increase in the values of a* and b* over time, which can be translated into an increase in yellow and a decrease in white, with a greater accentuation in the control sample. The rheological study allowed us to obtain a non-Newtonian flow behavior of the shear-thinning type for all samples, and the flow curves were well-fitted by the Sisko model (R2 &ge; 0.99). The samples had an elastic rather than viscous behavior, typical of dressings and emulsions. This indicates that the storage modulus was greater than the loss modulus (G&prime; &gt; G&Prime;) in the evaluated frequency range. (4) Conclusions: hydrocolloids from Dioscorea rotundata have potential as a fat substitute in emulsion-type products

Physicochemical, Rheological, and Microstructural Properties of Low-Fat Mayonnaise Manufactured with Hydrocolloids from <i>Dioscorea rotundata</i> as a Fat Substitute

(1) Background: In this study, the potential use of Dioscorea rotundata hydrocolloids was evaluated to develop low-fat mayonnaise. (2) Methods: The effect of different concentrations of hydrocolloids on the physicochemical, microstructural, and rheological properties of mayonnaise was evaluated. (3) Results: Physicochemical analyses showed pH values that were stable over time but decreased with increasing hydrocolloid concentration. The color parameters showed a decrease in luminosity and an increase in the values of a* and b* over time, which can be translated into an increase in yellow and a decrease in white, with a greater accentuation in the control sample. The rheological study allowed us to obtain a non-Newtonian flow behavior of the shear-thinning type for all samples, and the flow curves were well-fitted by the Sisko model (R2 ≥ 0.99). The samples had an elastic rather than viscous behavior, typical of dressings and emulsions. This indicates that the storage modulus was greater than the loss modulus (G′ > G″) in the evaluated frequency range. (4) Conclusions: hydrocolloids from Dioscorea rotundata have potential as a fat substitute in emulsion-type products

Natural Yogurt Stabilized with Hydrocolloids from Butternut Squash (Cucurbita moschata) Seeds: Effect on Physicochemical, Rheological Properties and Sensory Perception

Stabilizers are ingredients employed to improve the technological properties of products. The food industry and consumers have recently become interested in the development of natural ingredients. In this work, the effects of hydrocolloids from butternut squash (Cucurbita&nbsp;moschata) seeds (HBSS) as stabilizers on the physicochemical, rheological, and sensory properties of natural yogurt were examined. HBSS improved the yogurt’s physical stability and physicochemical properties, decreasing syneresis and modifying the samples’ rheological properties, improving the assessment of sensory characteristics. The samples presented shear thinning behavior characterized by a decrease in viscosity with the increase of the shear rate; nevertheless, the samples showed a two-step yield stress. HBSS is an alternative as a natural stabilizer for the development of microstructured products