Green synthesis of nanomaterials for smart biopolymer packaging: Challenges and outlooks

There are several physical and chemical methods for synthesizing nanomaterials, while the most appropriate techniques involve using green chemistry and eco-friendly material. Recently, green synthesized materials for different applications have gained attention as a result of their environmental friendliness and cost-effectiveness. Applying green synthesized nanoparticles (NPS) in food packaging has been extensively investigated. Biopolymers require filler to enhance the optical, barrier, thermal, antimicrobial, and mechanical properties of packaging. Biopolymer packaging incorporated with green synthesized NPs is expected to simultaneously enhance performance while reducing environmental damage. The current review article focuses on biopolymer films with bio (green)-synthesized nanomaterials and their effectiveness in reducing the negative environmental implications of synthetic packaging. It also covers the general concepts of green synthesis of NPs, their production methods, their performance, and characterization, and discusses the potential, performance and recent developments of bio-nanocomposite films/coatings in biodegradable food packaging. Recent reports and trends provide more insight into the impact of green synthesized nanomaterials on food packaging. Graphical Abstract: [Figure not available: see fulltext.]

Plant by-product antioxidants: control of protein-lipid oxidation in meat and meat products

Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGProtein-lipid oxidation is one of the main causes of quality deterioration in meat and meat products during processing and storage. The application of natural antioxidants in muscle food appears a sustainable option for reducing the consumption of synthetic antioxidants with confirmed carcinogenic and toxicological effects. Hence, the food industry today prefers low-cost natural additives instead of synthetic ones. Agro-food industry generates a large quantity of plant by-products annually during the cultivation and processing of agricultural products. There is a wide variety of natural antioxidants in plant by-products. Several parts of plant (seeds, peels, leaves, husks, stems, and roots) as unexploited novel sources of natural antioxidant can be applied either through technological strategies to control oxidative process in meat and meat products. This paper provides an overview of the current trends in the use of natural antioxidants from plant by-products for potential applications against protein–lipid oxidation in muscle food. In addition, the effect of encapsulation of plant by-product antioxidants on the protein–lipid oxidation of meat and meat products is reviewed.Xunta de Galicia | Ref. IN607A2019/0

Extraction Optimization, Functional and Thermal Properties of Protein from Cherimoya Seed as an Unexploited By-Product

Plant-based proteins are gaining in attraction compared with animal-based proteins due to their superior ethical profiles, growing concerns on the part of various organizations about animal health and welfare, and increased global greenhouse-gas emissions in meat production. In this study, the response surface methodology (RSM) using a Box-Behnken design (BBD) was applied to optimize the ultrasound-assisted alkaline extraction of cherimoya-seed proteins as valuable by-products. The effects of three pH, temperature, and time factors on the protein-extraction yield and protein content were investigated. The pH at 10.5 and temperature of 41.8 °C for 26.1 min were considered the optimal ultrasound-assisted alkaline-extraction conditions since they provided the maximum extraction yield (17.3%) and protein content (65.6%). An established extraction technique was employed to enhance the cherimoya-seed protein yield, purity, and functional properties. A thermogravimetric analysis (TGA) of the samples showed that the ultrasound-assisted alkaline extraction improved the thermal stability of the protein concentrate

Valorization of wastewater from table olives: NMR identification of antioxidant phenolic fraction and microwave single-phase reaction of sugary fraction

The table olive industry is producing a huge amount of wastewater, which is a post-processing cost and an environmental concern. The present study aims to valorize this processing by-product to obtain a value-added product, thereby enhancing resource efficiency and contributing to achieving sustainable development goals (SDGs). In this sense, a chemical reaction-based platform was developed to obtain valuable components, such as levulinic acid (LA) and 5-hydromethylfurfural (HMF). The products were then analyzed using NMR identification of the antioxidant phenolic fraction and microwave single-phase reaction of the sugary fraction. According to the results, the highest concentration of phenolic compounds does not correspond to the sample directly obtained from NaOH treatment (S1), indicating that water washing steps (S2-S5) are fundamental to recover phenolic substances. Moreover, glucose was presented in the sugary fraction that can be transformed into levulinic acid by a single-phase reaction under microwave irradiation. The information provided in this manuscript suggests that the wastewater from the olive processing industry can be valorized to obtain valuable products

Table olive wastewater as a potential source of biophenols for valorization : a mini review

The table olive industry generates high amounts of wastewater annually during the alkaline treatment, fermentation, and washing steps of olives. High conductivity and salt content, as well as the high organic and biophenol contents of these waters, is a worldwide problem, especially in the Mediterranean region, which is the major table olive producing area. There is a wide variety of bioactives found in wastewater derived from table olive processing. The main compounds of table olive wastewater, such as those derived from phenolic, hydrocarbon, and sugar fractions, can be recovered and reused. In this review, the table olive manufacturing processes and the volumes and composition of wastewater generated from the different methods of table olive processing are discussed. In addition, biophenols of table olive water and their biological activities are also introduced. The high concentrations of valuable biophenols, such as tyrosol and hydroxytyrosol, show promising potential for valorizing table olive wastewater; however, more research is needed in this area

Optimization of Extraction of Protein from Alfalfa Leaf (Medicago sativa) for Human Consumption

La creixent població mundial està augmentant la demanda de fonts de proteïnes vegetals dietètiques barates i més sostenibles per a complementar o fins i tot reemplaçar fonts cares i limitades de proteïna animal. L'alfals (Medicago sativa) és una important lleguminosa productiva farratgera, àmpliament conreada a tot el món. A causa de la seva alta qualitat nutricional i adaptabilitat, la proteïna de la fulla d'alfals s'usa principalment com un suplement alimentós, mentre que només juga un paper menor en el sector de l'alimentació humana. L'ús de concentrats de proteïnes vegetals derivats de l'alfals en l'alimentació humana està limitat per la seva qualitat negativa, com el color marró, el sabor amarg i els compostos antinutricionals. Després de la collita de les fulles d'alfals, les proteases endògenes de la fulla estan degradant la proteïna, mentre que els enzims polifenoloxidasa (PPO) i peroxidasa (POD) amb alta activitat inicial estan causant simultàniament l'ennegriment del teixit. El resultat d'aquestes accions és una proteïna fosca i parcialment degradada. Per a evitar aquests efectes negatius en la proteïna extreta, es va dur a terme un primer estudi sobre els efectes del blanqueig en vaporitzar les fulles d'alfals des del començament de la collita. El primer objectiu de la tesi va ser optimitzar la inactivació de PPO, POD i proteases de plantes en fulles d'alfals a través del procés de blanqueig de vapor. També es va investigar l'efecte d'aquest procés en l'índex d’enfosquiment, el color, el nitrogen no proteic i el pes molecular. Algunes de les propietats indesitjables de l'alfals poden deure's als nivells més alts de saponina com un factor antinutricional principal que es troba en l'alfals. La segona part de la tesi va tenir com a objectiu descobrir les condicions òptimes d'extracció assistida per ultrasò per a obtenir el major rendiment de soponines totals i la seva bioaccesibilitat per a la seva posterior aplicació en els aliments utilitzant la tècnica RSM. A més, s’ha emprat la irradiació UV per a la degradació de les saponines d'alfals a diferents temperatures i pH. En conseqüència, el procés d'extracció de la proteïna d'alfals com a aliment és extremadament important per aconseguir una proteïna d'alta qualitat sense cap problema de seguretat. Així, s’ha desenvolupat i utilitzat la tècnica de precipitació isoelèctrica alcalina assistida per ultrafiltració ultrasònica (UUAAIP) com un nou procés en l'extracció de proteïnes de les fulles d'alfals. Finalment, es van investigar la composició, les propietats fisicoquímiques i funcionals de la proteïna extreta i es van comparar amb els resultats d'altres mètodes comuns d'extracció. En cobrir tots els problemes esmentats, aquesta tesi tracta de proporcionar un aïllat de proteïna d'alfals d'alta qualitat sense cap problema de seguretat. Aquesta recerca suggereix que el blanqueig amb vapor de fulles d'alfals senceres fresques en condicions òptimes va ser útil per a evitar l'aparició del color fosc i la degradació de la proteïna extreta. Per tant, la combinació de mètodes d'extracció i purificació va crear un mètode nou i eficient, que pot millorar la puresa, la seguretat, la qualitat i les propietats funcionals de la proteïna d'alfals. La UUAAIP és una tècnica apropiada per a fabricar aïllats de proteïna d'alfals i podria resoldre les restriccions del consum humà de proteïna d'alfals.La creciente población mundial está aumentando la demanda de fuentes de proteínas vegetales dietéticas baratas y más sostenibles para complementar o incluso reemplazar fuentes caras y limitadas de proteína animal. La alfalfa (Medicago sativa) es una importante leguminosa productiva forrajera, ampliamente cultivada en todo el mundo. Debido a su alta calidad nutricional y adaptabilidad, la proteína de la hoja de alfalfa se usa principalmente como un suplemento alimenticio, mientras que solo juega un papel menor en el sector de la alimentación humana. El uso de concentrados de proteínas vegetales derivados de la alfalfa en la alimentación humana está limitado por su calidad negativa, como el color pardo, el sabor amargo y los compuestos antinutricionales. Después de la cosecha de las hojas de alfalfa, las proteasas endógenas de la hoja están degradando la proteína, mientras que las enzimas polifenoloxidasa (PPO) y peroxidasa (POD) con alta actividad inicial están causando simultáneamente el pardeamiento del tejido. El resultado de estas acciones es una proteína oscura y parcialmente degradada. Para evitar estos efectos negativos en la proteína extraída, se llevó a cabo un primer estudio sobre los efectos del blanqueo al vaporizar las hojas de alfalfa desde el comienzo de la cosecha. El primer objetivo de la tesis fue optimizar la inactivación de PPO, POD y proteasas de plantas en hojas de alfalfa a través del proceso de blanqueo de vapor. También se investigó el efecto de este proceso en el índice de pardeamiento, el color, el nitrógeno no proteico y la masa molecular. Algunas de las propiedades indeseables de la alfalfa pueden deberse a los niveles más altos de saponina como un factor antinutricional principal que se encuentra en la alfalfa. La segunda parte de la tesis tuvo como objetivo hallar las condiciones óptimas de extracción asistida por ultrasonido para obtener el mayor rendimiento de saponinas totales y su bioaccesibilidad para su posterior aplicación en los alimentos utilizando la técnica RSM. Además, se ha utilizado la irradiación UV para la degradación de las saponinas de alfalfa a diferentes temperaturas y pH. En consecuencia, el proceso de extracción de la proteína de alfalfa como alimento es extremadamente importante para lograr una proteína de alta calidad sin ningún problema de seguridad. Así, se ha desarrollado y utilizado la técnica de precipitación isoeléctrica alcalina asistida por ultrafiltración ultrasónica (UUAAIP) como un nuevo proceso en la extracción de proteínas de las hojas de alfalfa. Finalmente, se investigaron la composición, las propiedades fisicoquímicas y funcionales de la proteína extraída y se compararon con los resultados de otros métodos comunes de extracción. Al cubrir todos los problemas mencionados, esta tesis trata de proporcionar un aislado de proteína de alfalfa de alta calidad sin ningún problema de seguridad. Esta investigación sugiere que el blanqueo con vapor de hojas de alfalfa enteras frescas en condiciones óptimas fue útil para evitar la aparición del color oscuro y la degradación de la proteína extraída. Por lo tanto, la combinación de métodos de extracción y purificación creó un método nuevo y eficiente, que puede mejorar la pureza, la seguridad, la calidad y las propiedades funcionales de la proteína de alfalfa. La UUAAIP es una técnica apropiada para obtener aislados de proteína de alfalfa y podría resolver las restricciones del consumo humano de proteína de alfalfa.The world’s growing population is raising the demand for sources of cheap and more sustainable dietary plant proteins to supplement or even replace expensive and limited sources of animal protein. Alfalfa (Medicago sativa) is an important productive forage legume, widely cultivated around the world. Owing to its high nutritional quality and adaptability, the alfalfa leaf protein is mainly used as a feed supplement, while it only plays a minor role in the human food sector. The use of plant protein concentrates derived from alfalfa in human food is limited by their negative quality such as brown color, bitter taste, and anti-nutritional compounds. After harvesting of the alfalfa leaves, the endogenous proteases of the leaf are degrading the protein while the polyphenol oxidase (PPO) and peroxidase (POD) enzymes with high initial activity are simultaneously causing browning in the tissue. The result of these actions is a dark and a partially degraded protein. To avoid these negative effects in the extracted protein, the authors carried out a first study on the effects of blanching by steaming the leaves of alfalfa from the beginning of the harvest. The first aim of the thesis was to optimize the inactivation of PPO, POD and plant proteases in alfalfa leaves through the steam blanching process. The effect of this process on the browning index, color, non-protein nitrogen and molecular weight was also investigated. Some of undesirable properties of alfalfa may be due to the higher levels of saponin as a main anti-nutritional factor found in alfalfa. The second part of thesis aimed to find out the optimal conditions of ultrasound-assisted extraction for obtaining the highest yield of total saponins and their bioaccessibility for further application in the food using the RSM. Beside, UV irradiation has been employed for degradation of alfalfa saponins in different temperature and pH. Accordingly, the extraction process of alfalfa protein as a food is extremely important for achieving a high quality protein without any safety concerns. So the ultrasonic-ultrafiltration-assisted Alkaline Isoelectric precipitation (UUAAIP) technique as a new process was developed and employed in the alfalfa leaves’ protein extraction. Finally, the composition, physiochemical and functional properties of the extracted protein were investigated and compared with the results of other extraction common methods. By covering all the mentioned issues, this thesis tries to provide alfalfa protein isolate with high quality without any safety concerns. This research suggests that steam blanching of fresh whole alfalfa leaves under the optimum conditions was helpful for avoiding the appearance of the dark color appears and the degradation of the extracted protein. Thus, the combination of methods of extraction and purification created a new and efficient method, which is able to improve the purity, safety, quality and functional properties of alfalfa protein. UUAAIP is an appropriate technique for manufacturing alfalfa protein isolates and could resolve restrictions of human consumption of alfalfa protein

Recent Advances in Potential Health Benefits of Quercetin

Quercetin, a flavonoid found in fruits and vegetables, has been a part of human diets for centuries. Its numerous health benefits, including antioxidant, antimicrobial, anti-inflammatory, antiviral, and anticancer properties, have been extensively studied. Its strong antioxidant properties enable it to scavenge free radicals, reduce oxidative stress, and protect against cellular damage. Quercetin's anti-inflammatory properties involve inhibiting the production of inflammatory cytokines and enzymes, making it a potential therapeutic agent for various inflammatory conditions. It also exhibits anticancer effects by inhibiting cancer cell proliferation and inducing apoptosis. Finally, quercetin has cardiovascular benefits such as lowering blood pressure, reducing cholesterol levels, and improving endothelial function, making it a promising candidate for preventing and treating cardiovascular diseases. This review provides an overview of the chemical structure, biological activities, and bioavailability of quercetin, as well as the different delivery systems available for quercetin. Incorporating quercetin-rich foods into the diet or taking quercetin supplements may be beneficial for maintaining good health and preventing chronic diseases. As research progresses, the future perspectives of quercetin appear promising, with potential applications in nutraceuticals, pharmaceuticals, and functional foods to promote overall well-being and disease prevention. However, further studies are needed to elucidate its mechanisms of action, optimize its bioavailability, and assess its long-term safety for widespread utilization

Bioactive peptide fractions from collagen hydrolysate of common carp fish byproduct: antioxidant and functional properties

Collagen isolated from byproducts of common carp was hydrolyzed with alcalase enzyme to obtain peptide fractions. The resulting >30 kDa (PF1), 10–30 kDa (PF2), 3–10 kDa (PF3) and <1 kDa (PF4) fractions were studied for their antioxidant and functional properties. All peptide fractions illustrated antioxidant activity at different concentrations (1, 5, and 10 mg/mL). Although PF4 indicated the highest DPPH radical-scavenging activity (87%) at a concentration of 1 mg/mL, the highest reducing power (0.34) and hydroxyl radical scavenging activity (95.4%) were also observed in PF4 at a concentration of 10 mg/mL. The solubility of the peptide fractions was influenced by pH. The lowest solubility of the peptide fractions was observed at pH 4. The highest emulsifying activity index (EAI) was observed for PF4 (121.1 m2/g), followed by PF3 (99.6 m2/g), PF2 (89.5 m2/g) and PF1 (78.2 m2/g). In contrast to what has been found in the case of EAI, the emulsion stability of the peptide fractions decreased at lower molecular weight, which ranged from 24.4 to 31.6 min. Furthermore, it was revealed that PF1 had the highest foam capacity (87.4%) and foam stability (28.4 min), followed by PF2 and PF3. Overall, the findings suggest that peptide fractions isolated from byproducts of common carp are a promising source of natural antioxidants for application in functional food and pharmaceutical products