Valorization of okara by-product for obtaining soluble dietary fibers and their use in biodegradable carboxymethyl cellulose-based film.

In the face of mounting environmental concerns and the need for sustainable innovation, the use of agro-industrial wastes as raw materials offers a promising pathway. In this context, this study investigated the okara, a by-product of soy processing, as a novel source of soluble dietary fiber for the enrichment of carboxymethyl cellulose (CMC) biodegradable films based on environmental benefits of waste reduction with the creation of renewable packaging alternatives. Okara soluble dietary fiber (OSDF)-enriched CMC film was compared with films made from traditional and innovative soluble dietary fibers, such as pectin, inulin, and ß-glucan. OSDF was obtained through acid hydrolysis at 121 °C, achieving a yield of 5.31 % relative to its initial dry weight. All the produced films exhibited a maximum crystallinity of 5 %, as revealed by X-ray diffraction (XRD), indicative of their largely amorphous structure, while scanning electron microscopy (SEM) ensured their uniformity and flawlessness. The CMC film enriched with okara soluble dietary fiber exhibited key properties, such as thickness, water vapor permeability, and thermal stability, comparable to other soluble fibers studied. These characteristics are essential for effective packaging applications. A notable distinction of the OSDF-enriched film was its capacity to block UV light, offering protection for light-sensitive items. The solubility tests showed that okara and ß-glucan contributed to films with a higher solubility percentage. Mechanical testing underscored the influence of fiber on tensile strength, with the film enriched with ß-glucan outperforming others at 27.5 MPa. All films showed rapid biodegradation within one week, emphasizing their eco-friendliness and the study alignment with sustainable development objectives in packaging.

O uso de embalagens cartonadas no envase asséptico de alimentos e bebidas: uma revisão narrativa / The use of carton packaging in the aseptic packaging Of food and beverages: a narrative review

A embalagem constitui um importante componente para a preservação de alimentos. Um dos avanços mais notáveis na tecnologia de alimentos foi o método de envase asséptico, criado para atender à necessidade de prolongar a vida útil dos alimentos, otimizar a qualidade do produto e reduzir custos. A embalagem cartonada pode ser utilizada no envase asséptico e está presente em diversos mercados, como o de lácteos, sucos, e até alimentos sólidos, como vegetais e grãos. O presente trabalho fez uma revisão narrativa da literatura científica com informações de estudos disponíveis sobre o uso da embalagem cartonada no envase asséptico de alimentos e bebidas, com ênfase nos aspectos nutricionais, sensoriais e de sustentabilidade. As embalagens cartonadas são consideradas seguras e não foram identificados na literatura problemas de saúde associados a elas. O alumínio presente nas embalagens não possui proximidade direta com o alimento, pois existe uma camada interna de polietileno de baixa densidade que entra em contato com o produto. O envase asséptico em embalagens cartonadas não possui impacto negativo na qualidade nutricional dos produtos e as tecnologias disponíveis são capazes de preservar as características sensoriais dos mesmos. O envase em embalagens que atuam como uma barreira à luz e oxigênio, como a embalagem cartonada, pode representar uma boa alternativa para redução de alterações físico-químicas em alimentos. Alguns obstáculos ainda dificultam a reciclagem completa das embalagens cartonadas, no entanto, esforços e investimentos vêm sendo empregados para encontrar novas soluções.(AU)

Packaging is an important component for food preservation. One of the most notable advances in food technology has been the aseptic filling method, created to meet the need to extend the shelf life of food, optimize product quality and reduce costs. Carton packaging can be used in aseptic packaging and is present in several markets, such as dairy products, juices, and even solid foods, such as vegetables and grains. The present work carried out a narrative review of the scientific literature with information from available studies on the use of carton packaging in the aseptic packaging of food and beverages, with an emphasis on nutritional, sensory and sustainability aspects. Carton packaging is considered safe and no health problems associated with it have been identified in the literature. The aluminum present in the packaging is not directly close to the food, as there is an internal layer of low-density polyethylene that comes into contact with the product. Aseptic packaging in carton packaging does not have a negative impact on the nutritional quality of products and the available technologies are capable of preserving their sensory characteristics. Filling in packaging that acts as a barrier to light and oxygen, such as carton packaging, can represent a good alternative for reducing physical-chemical changes in food. Some obstacles still make it difficult to completely recycle carton packaging, however, efforts and investments have been made to find new solutions.(AU)

Assessing the reinforcement effect by response surface methodology of holocellulose from spent coffee grounds on biopolymeric films as food packaging materials.

The pollution caused by petroleum-derived plastic materials has become a major environmental problem that has encouraged the development of new compostable and environmentally friendly materials for food packaging based on biomodified polymers with household residues. This study aims to design, synthesize, and characterize a biobased polymeric microstructure film from polyvinyl alcohol and chitosan reinforced with holocellulose from spent coffee grounds for food-sustainable packaging. Chemical isolation with a chlorite-based solution was performed to obtain the reinforced holocellulose from the spent coffee ground, and the solvent casting method was used to obtain the films to study. Physicochemical and microscopic characterizations were conducted to identify and select the best formulations using a simplex-centroid design analysis. The response surface methodology results indicate that the new packaging material obtained with equal amounts of polymers and reinforced material (1:1:1) possesses the appropriate barrier properties and microstructural character to prevent water attack and hydrophobic behavior and thus could be used as an alternative for food packaging materials.

Biodegradable starch foams reinforced by food-chain side streams.

Biodegradable starch foam trays offer an eco-friendly substitute for petroleum-based single-use packaging, notably polystyrene foams. However, they lack flexibility, tensile strength, and water-sensitivity, addressable through lignocellulosic reinforcement. This study aimed to develop biodegradable starch foam trays filled with different food-chain side streams for sustainable alternative packaging. Corncob, soybean straw, cassava peel, araucaria seed hull, yerba mate stalks and yerba mate leaves petiole were collected, dried and ground to <250 µm. The trays were filled with 13 % (w/w) of each food-chain side streams and produced by hot molding. The trays morphology, moisture, water activity (aw), thickness, bulk density, tensile strength, elongation at break, Young's modulus, bending strength, maximum deflection, and sorption isotherms were investigated. Reinforcements slightly increased the foams bulk density, reduced the tensile strength and maximum deflection and while bending strength increased from 0.20 MPa to 1.17-1.80 MPa. The elasticity modulus decreased by adding any filling, that resulted in ductility improvement; however, these packaging have moisture-sensitive material especially for aw higher than 0.52, which drives the use recommendation for dry products storage or shipping/transport. The biodegradable starch foam trays filled with side streams were successfully produced and offer excellent alternative to petroleum-based packaging low-density material with bending strength improved.

Effects of PVA and yerba mate extract on extruded films of carboxymethyl cassava starch/PVA blends for antioxidant and mechanically resistant food packaging.

Global concerns over environmental damage caused by non-biodegradable single-use packaging have sparked interest in developing biomaterials. The food packaging industry is a major contributor to non-degradable plastic waste. This study investigates the impact of incorporating different concentrations of polyvinyl alcohol (PVA) and yerba mate extract as a natural antioxidant into carboxymethyl cassava starch films to possibly use as active degradable packaging to enhance food shelf life. Films with starch and PVA blends (SP) at different ratios (SP radios of 100:0, 90:10, 80:20 and 70:30) with and without yerba mate extract (Y) were successfully produced through extrusion and thermoforming. The incorporation of up to 20 wt% PVA improved starch extrusion processing and enhanced film transparency. PVA played a crucial role in improving the hydrophobicity, tensile strength and flexibility of the starch films but led to a slight deceleration in their degradation in compost. In contrast, yerba mate extract contributed to better compost degradation of the blend films. Additionally, it provided antioxidant activity, particularly in hydrophilic and lipophilic food simulants, suggesting its potential to extend the shelf life of food products. Starch-PVA blend films with yerba mate extract emerged as a promising alternative for mechanically resistant and active food packaging.

Smart labels based on polyvinyl alcohol incorporated with chitosan nanoparticles loaded with grape extract: Functionality, stability and food application.

Anthocyanins (ACNs) are natural compounds with potential applications due to their colorimetric response to pH. Due to their sensitivity to various environmental factors, nanoencapsulation with biopolymers is a successful strategy for stabilizing ACNs. In this work ACNs were extracted from grape skins and encapsulated into chitosan (CS) nanoparticles by ionic gelation using sodium tripolyphosphate (TPP) as a cross-linking agent. CS nanoparticles loaded with ACNs had particle sizes between 291 and 324 nm and polydispersity index around 0.3. The encapsulation efficiency of ACNs was approximately 60 %; and encapsulated anthocyanins (ACN-NPs) exhibited color change properties under different pH conditions. pH-sensitive labels based on polyvinyl alcohol (PVA) were prepared by the casting method. The effect of incorporating ACN-NPs on the physical, structural, and pH-sensitive properties of PVA labels was evaluated, and its application as shrimp freshness indicator was studied. The nanoencapsulation protected ACNs against heat and light treatments, preserving the original purple color. When applying the label, visible changes from red to blue until reaching yellow were observed with the change in the quality of the shrimp at the refrigeration temperature. The results suggest that PVA labels containing ACNs encapsulated in C-NPs can be used as smart packaging labels in the food industry.

Functional characterization of biodegradable films obtained from whole Paecilomyces variotii biomass.

The indiscriminate use of petroleum-based polymers and plastics for single-use food packaging has led to serious environmental problems due the non-biodegradable characteristics. Thus, much attention has been focused on the research of new biobased and biodegradable materials. Yeast and fungal biomass are low-cost and abundant sources of biopolymers with highly promising properties for the development of biodegradable materials. This study aimed to select a preparation method to develop new biodegradable films using the whole biomass of Paecilomyces variotii subjected to successive physical treatments including ultrasonic homogenization (US) and heat treatment. Sterilization process had an important impact on the final filmogenic dispersion and mechanical properties of the films. Longer US treatments produced a reduction in the particle size and the application of an intermediate UT treatment contributed favorably to the breaking of agglomerates allowing the second US treatment to be more effective, achieving an ordered network with a more uniform distribution. Samples that were not filtrated after the sterilization process presented mechanical properties similar to plasticized materials. On the other hand, the filtration process after sterilization eliminated soluble and hydratable compounds, which produced a reduction in the hydration of the films.

Assessment of the risk of contamination of enteral nutrition bottles based on the simulation of home use conditions and hygiene procedures.

BACKGROUND: Home-prepared enteral formulations are supplied to patients through enteral nutrition bottles, via a gravity bag or other container, which may be inadequately sanitized and reused more times than recommended by the manufacturer. Such procedures increase the risk of contamination and can compromise the patient's clinical outcome. In light of this, the present study aimed to assess the risk of contamination of enteral nutrition bottles by simulating home use conditions and hygiene procedures. METHODS: A simulation of bottle usage was conducted across the three categories of enteral nutrition (homemade enteral preparations, blended enteral preparations, and commercial enteral formulas) for 3 days, using three hygiene procedures reported by caregivers: use of detergent (DET); use of detergent and boiling water (DET+BW); and use of detergent and bleach (DET+BL). The microbiological contamination was determined by the analysis of aerobic mesophilic microorganisms. RESULTS: The bottles that were used for 3 days, regardless of the enteral nutrition category, were within the acceptable limit for aerobic mesophilic microorganisms (between <4 and 8.0 colony-forming units [CFU]/cm2) when sanitized using the DET+BW and DET+BL procedures. The enteral nutrition bottles, when cleaned using the DET procedure during the 3 days of usage, showed low microbial contamination (between <4 and 3.0 CFU/cm2) in blended preparation and commercial formula only. CONCLUSION: Thus, regardless of the enteral nutrition category, we found that the bottles can be used for 3 days, as long as the DET+BW or DET+BL hygiene procedure is applied and safe food handling measures are adopted.

Bacterial microbiota shifts in vacuum-packed beef during storage at different temperatures: Impacts on blown pack spoilage.

We aimed to evaluate the bacterial growth and diversity in vacuum-packed beef bags stored at different temperatures and to monitor blown-pack spoilage. We used culture-based methods and high-throughput sequencing to study the development of the main bacterial groups naturally present in beef stored at 4 and 15 °C for 28 days. The growth of sulfite-reducing clostridium (SRC) was impaired in beef bags stored at 4 °C; significant differences among SRC counts were observed in beef bags stored at 4 and 15 °C on days 14, 21, and 28 (P = 0.001). Blown pack was observed in most beef bags stored at 15 °C, from day 14 to day 28, but not in beef bags stored at 4 °C. A storage temperature of 4 °C was able to maintain a stable bacterial microbiota (most prevalent: Photobacterium, Hafnia-Obesumbacterium, and Lactococcus). Remarkable changes in microbial abundance occurred at 15 °C from day 14 to day 28, with a predominance of strict anaerobes (Bacteroides) and the presence of Clostridium spp. The relative frequencies of strict anaerobes and Clostridium were statistically higher in the beef bags stored at 15 °C (P < 0.001 and P = 0.004, respectively). The temperature influenced the microbial counts and relative abundance of spoilage bacteria, leading to blown pack spoilage.

Development of ternary polymeric films based on cassava starch, pea flour and green banana flour for food packaging.

The development of alternative materials to replace plastics used in food packaging is an important approach to reducing environmental pollution and minimizing harmful impacts on ecosystems. In this study, biopolymeric films were formulated using cassava starch (Manihot esculenta Crantz), pea flour (Pisum sativum) and green banana flour (Musa sp.) to obtain a material for application in food packaging. The influence of a plasticizer on the optical and physicochemical properties of the films was analyzed and the synergy between higher concentrations of starch and plasticizer resulted in films with low opacity. In addition, the morphology, thermal, mechanical and barrier properties were examined. The film with the best formulation (p < 0.05) contained 12 g cassava starch, 3.6 g pea flour and 30 % glycerol (the maximum levels of the experiment). This film presented average values of thickness, moisture, solubility, opacity, maximum strength (F), maximum tensile stress (σ), elongation at break (ε) and elasticity (E) of 0.47 mm, 19.95 %, 87.45 %, 20.93 %, 9.30 N, 1.75 MPa, 30.10 % and 5.93 %, respectively. This research demonstrates the potential application of films obtained by combining starches from different sources. The sustainable production of environmentally-friendly packaging provides an alternative to fossil-based plastics, which have well-documented adverse effects on the environment.

Biodegradable PBAT/PLA blend films incorporated with turmeric and cinnamomum powder: A potential alternative for active food packaging.

Active packaging made from biodegradable polymers and natural additives appears as an ecological alternative. In addition to having antioxidant activity and enhancing food preservation, it allows mitigating the negative impacts caused by improper disposal. This study pursued to produce biodegradable films based on a polymer blend PBAT/PLA (Ecovio®) using the flat extrusion method. The films were prepared with the incorporation of 5 wt% of powdered turmeric or cinnamon as natural additives. The films obtained, and those reprocessed twice, were characterized in terms of colorimetric, UV light transmittance, water contact angle, water vapor permeability, morphology, mechanical properties, and antioxidant activity. Cinnamon reduced the UV light transmittance and made a surface more hydrophobic. Reprocessing led to greater elongation and maximum load, associated with increased dispersion and distribution, as evidenced in the morphological analysis. The films developed have significant potential for applications in active food packaging, with emphasis on cinnamon-additivated films.

Effect of beef long-storage under different temperatures and vacuum-packaging conditions on meat quality, oxidation processes and microbial growth.

BACKGROUND: The global beef market demands the meat industry to ensure product quality and safety in markets that are often very distant. The present study aimed to evaluate the effects of chilled (CH, 120 d) and chilled-then-frozen (CHF, 28 d + 92 d) storage conditions of beef vacuum packaged (VP) and vacuum packaged with antimicrobial (VPAM) on meat quality, oxidative status and microbial loads. Treatments resulted from the combination of storage condition and packaging type: VP + CH, VP + CHF, VPAM + CH and VPAM + CHF. RESULTS: Warner-Bratzler shear force values decreased in all treatments after 28 d of chilling. Except for VP + CH, L* values (lightness) of meat color did not differ in each treatment as the storage time increased. Meat from VP + CH had greater a* values than CHF treatments on day 120 of storage. A consumer panel did not detect differences in tenderness, flavor and overall liking between VP and VPAM beef, but they preferred CHF steaks rather than CH beef. TBARS values did not differ between VP and VPAM and between CH and CHF at any time during the storage period. At the end of storage time, all treatments except VP + CHF presented a greater concentration of thiols than at 48 h post-mortem. On day 120 of storage, VP + CH had greater catalase enzyme activity than CHF treatments while VP + CH and VP + CHF showed a greater superoxide dismutase activity than VPAM + CHF. Storage condition (CH or CHF) had a greater impact on microbial counts than the type of packaging. CONCLUSION: Freezing meat after an ageing period represents a suitable strategy to extend beef storage life without a detrimental impact on its quality. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Use of Nile tilapia (Oreocromis niloticus) processing residues in the production of pâtés with the addition of oregano (Origanum vulgare) essential oil.

The effect of the use of Nilo tilapia filleting residues in the production of pâtés with the addition of oregano essential oil stored for 90 days at 4 °C was evaluated. For that, 5 treatments were performed as follows: TSA-control treatment; TES with the addition of sodium erythorbate; and formulation TOE1 with 600 ppm oregano essential oil; TOE2 with 1000 ppm essential oil; and TOE3 with 1400 ppm essential oil. The pâtés showed adequate technological and physicochemical characteristics and microbiological counts within the legislation standards. No significant differences were observed in the luminosity of the pâté formulations during storage, and the addition of oil contributed to the increase in a* values and stability of b* values. Regarding the lipid and protein oxidation, TOE3 showed lower values at the end of the shelf-life. The addition of essential oil did not affect the hardness and cohesiveness of the products. The fatty acids in greater amounts in the samples were linoleic, oleic, palmitic, and stearic acids. The analysis of biogenic amines indicated that only the treatments with the highest amounts of sodium erythorbate (TES and TOE1) showed losses of spermidine. It was observed that decreasing the inclusion of sodium erythorbate and increasing the inclusion of oregano essential oil resulted in a drop in cadaverine values. A total of 46 volatile compounds were detected in the samples with the highest amount of free fatty acids and all the formulations were well accepted sensorially.

κ-Carrageenan/poly(vinyl alcohol) functionalized films with gallic acid and stabilized with metallic ions.

Given the environmental issues caused by the extensive use of conventional petroleum-based packaging, this work proposes functional films based on commercial κ-carrageenan (κc), poly(vinyl alcohol) (PVA), and gallic acid (GA) prepared by the "casting" method. Metallic ions in the κc composition stabilized the films, supporting processability and suitable mechanical properties. However, the incorporated GA amount (6.25 and 10 wt%) in the films created from an aqueous κc solution at 3.0 % wt/v (κc3) prevented crystalline domains in the resulting materials. The κc3/GA6.25 and κc3/GA10 films had less tensile strength (8.50 ± 0.61 and 10.28 ± 0.65 MPa) and high elongation at break (2.36 ± 0.16 and 1.19 ± 0.17 %) compared to the other samples, respectively. Low κc contents (κc2.5/GA6.25 and κc2.5/GA10) promoted stiff films and less permeability to water vapor (5.36 ± 0.51 and 3.76 ± 0.02 [×10-12 g(Pa × m × s)-1], respectively. The κc/GA weight ratio also influenced the film wettability, indicating water contact angles (WCAs) between 55 and 74°. The surface wettability implies a low oil permeability and high water swelling capacity of up to 1600 %. The κc/GA also played an essential role in the film's antimicrobial action against Staphylococcus aureus and Escherichia coli. Thus, the κc3/GA10 film showed suitable physical, chemical, and biological properties, having the potential to be applied as food coatings.

Shelf life estimation of refrigerated vacuum packed beef accounting for uncertainty.

This study estimates the shelf life of vacuum packed beef meat (three muscles: striploin (longissimus thoracis et lumborum, LTL), tenderloin (psoas major, PM) and outside chuck (trapezius thoracis, TT)) at refrigeration temperatures (0 °C-10 °C) based on modelling the growth of two relevant groups of spoilage microorganisms: lactic acid bacteria (LAB) and Enterobacteriaceae. The growth models were developed combining a two-step and a one-step approach. The primary modelling was used to identify the parameters affecting the growth kinetics, guiding the definition of secondary growth models. For LAB, the secondary model included the effect of temperature and initial pH on the specific growth rate. On the other hand, the model for Enterobacteriaceae incorporated the effect of temperature on the specific growth rate and the lag phase; as well as the effect of the initial pH on the specific growth rate, the lag phase and the initial microbial count. We did not observe any significant effect of the type of muscle on the growth kinetics. Once the equations were defined, the models were fitted to the complete dataset using a one-step approach. Model validation was carried out by cross-validation, mitigating the impact of an arbitrary division between training and validation sets. The models were used to estimate the shelf life of the product, based on the maximum admissible microbial concentration (7 log CFU/g for LAB, 5 log CFU/g for Enterobacteriaceae). Although LAB was the dominant microbiota, in several cases, both LAB and Enterobacteriaceae reached the critical concentration practically at the same time. Furthermore, in some scenarios, the end of shelf life would be determined by Enterobacteriaceae, pointing at the potential importance of non-dominant microorganisms for product spoilage. These results can aid in the implementation of effective control measures in the meat processing industry.

Correlation between natural microbial load and formation of ropy slime affecting the superficial color of vacuum-packaged cooked sausage.

The present study outlines a comprehensive correlation between the natural microbial load, which is predominantly composed of heat-resistant sporous-forming Bacillus, and the changes in the original properties related to the superficial color of vacuum-packaged cooked sausages. For this purpose, microbial growth curves were plotted by stimulating the growth of the natural microbiota in sausage packages at different temperatures. The correlations were investigated during sample incubation by the instrumental evaluation of color and the ropy slime detection on the sausage surface. The entrance of the natural microbiota into the stationary phase (ca. 9.3 log cfu/g) resulted in changes in the superficial color, which was demonstrated by the discoloration of vacuum-packaged cooked sausages. Therefore, it seems to be a suitable borderline for predictive models applied in durability studies that aim to estimate the period in which vacuum-packaged cooked sausages keep their typical superficial color, anticipating product refusal in markets.

Development and Evaluation of the Properties of Active Films for High-Fat Fruit and Vegetable Packaging.

ß-cyclodextrin and allyl isothiocyanate inclusion complexes (ß-CD:AITC) have been proposed for developing fresh fruit and vegetable packaging materials. Therefore, the aim of this research was to develop active materials based on poly(lactic acid) (PLA) loaded with ß-CD:AITC and to assess changes in the material properties during the release of AITC to food simulants. PLA films with 0, 5 and 10 wt.% ß-CD:AITC were developed by extrusion. Surface properties were determined from contact angle measurements. Films were immersed in water, aqueous and fatty simulants to assess the absorption capacity and the change in the thermal properties. Moreover, the release of AITC in both simulants was evaluated by UV-spectroscopy and kinetic parameters were determined by data modeling. Results showed that a higher concentration of ß-CD:AITC increased the absorption of aqueous simulant of films, favoring the plasticization of PLA. However, the incorporation of ß-CD:AITC also avoided the swelling of PLA in fatty simulant. These effects and complex relationships between the polymer, inclusion complexes and food simulant explained the non-systematic behavior in the diffusion coefficient. However, the lower partition coefficient and higher percentage of released AITC to the fatty simulant suggested the potential of these materials for high-fat fruit and vegetable active packaging applications.

Improved Antioxidant and Mechanical Properties of Food Packaging Films Based on Chitosan/Deep Eutectic Solvent, Containing Açaí-Filled Microcapsules.

The development of biobased antioxidant active packaging has been valued by the food industry for complying with environmental and food waste concerns. In this work, physicochemical properties for chitosan composite films as a potential active food packaging were investigated. Chitosan films were prepared by solution casting, plasticized with a 1:2 choline chloride: glycerol mixture as a deep eutectic solvent (DES) and incorporated with 0-10% of optimized açaí oil polyelectrolyte complexes (PECs). Scanning electron microscopy and confocal laser scanning microscopy revealed that the chitosan composite films were continuous and contained well-dispersed PECs. The increased PECs content had significant influence on the thickness, water vapor permeability, crystallinity (CrD) and mechanical and dynamic behavior of the films, as well as their antioxidant properties. The tensile strength was reduced in the following order: 11.0 MPa (control film) > 0.74 MPa (5% DES) > 0.63 MPa (5% DES and 5% PECs). Films containing 2% of PECs had an increased CrD, ~6%, and the highest elongation at break, ~104%. Films with 1% of PECs displayed the highest antioxidant properties against the ABTS and DPPH radicals, ~6 and ~17 mg TE g-1, respectively, and highest equivalent polyphenols content (>0.5 mg GAE g-1). Films with 2% of particles were not significantly different. These results suggested that the chitosan films that incorporated 1-2% of microparticles had the best combined mechanical and antioxidant properties as a potential material for food packaging.

Schiff base crosslinked gelatin-Spirulina platensis protein concentrate films with enhanced antioxidant activity.

The aim of this work is to produce bioactive films suitable for aerobic packaging applications by combining the bioactivity of Spirulina platensis protein concentrate (PC; 1% and 2% w/w), the sustainable nature of bovine gelatin (Ge), and sodium alginate dialdehyde (ADA, 5% w/w) as Schiff base crosslinking agent. PC was obtained by an optimized acid-base extraction process and characterized. PC showed a dose-dependent radical scavenging activity (RSA; IC50  = 24.3 mg/L) related to its high content of C-phycocyanin and total phenolic compounds (32.44 ± 1.37 mg gallic acid equivalents per gram of PC). As a general trend, crosslinking decreased the water solubility, improved mechanical properties, and helped improve RSA of Ge-ADA-PC films. Ge-5ADA-2PC film recorded best compromise between solubility (only 33.6%), high UV barrier (0.134% transmittance at 400 nm), reasonable extensibility (217.00 ± 2.34%), tensile strength (3.50 ± 0.43 MPa), water vapor permeability (2.00 ± 0.17 × 10-12  kg·m/m2 ·Pa·s), and RSA (44.70 ± 2.19%). Wrapping hake fillets in this filmdelayed lipid oxidation during storage under refrigerated conditions for 11 days, maintaining the thiobarbituric acid index below 0.5 mg malonaldehyde/kg muscle. Results suggest that Ge-ADA-PC films have potential as aerobic packaging materials for oxidation-sensitive food. PRACTICAL APPLICATION: The combination of gelatin, alginate dialdehyde and Spirulina platensis protein concentrate gave rise to fully biobased films with reduced water solubility and enhanced antioxidant activity, which were able to delay the secondary lipid oxidation of refrigerated seafood. This study also shows the potential of cyanobacteria as renewable resources of high-value ingredients for the design of active and intelligent aerobic packaging solutions.

Biopolymers as green-based food packaging materials: A focus on modified and unmodified starch-based films.

The ideal food packaging materials are recyclable, biodegradable, and compostable. Starch from plant sources, such as tubers, legumes, cereals, and agro-industrial plant residues, is considered one of the most suitable biopolymers for producing biodegradable films due to its natural abundance and low cost. The chemical modification of starch makes it possible to produce films with better technological properties by changing the functional groups into starch. Using biopolymers extracted from agro-industrial waste can add value to a raw material that would otherwise be discarded. The recent COVID-19 pandemic has driven a rise in demand for single-use plastics, intensifying pressure on this already out-of-control issue. This review provides an overview of biopolymers, with a particular focus on starch, to develop sustainable materials for food packaging. This study summarizes the methods and provides a potential approach to starch modification for improving the mechanical and barrier properties of starch-based films. This review also updates some trends pointed out by the food packaging sector in the last years, considering the impacts of the COVID-19 pandemic. Perspectives to achieve more sustainable food packaging toward a more circular economy are drawn.