Carolina Cecilia Acebal

This study explores the valorization of olive pomace through the green recovery of bioactive phenolic compounds for application in active packaging for olive oil preservation, alongside the development of a low-cost analytical strategy aligned with white analytical chemistry principles. Ultrasound-assisted extraction using 50% (v/v) aqueous ethanol significantly improved polyphenol recovery, reducing extraction time to 2 min while increasing efficiency compared to conventional maceration. Total phenolic content was determined using the Folin–Ciocalteu method and measured with both a UV–Vis spectrophotometer and a portable 3D-printed smartphone-based device, which showed excellent agreement with the reference method and comparable analytical performance. Optimized extracts were incorporated into starch–glycerol films, enhancing UV-barrier properties and enabling controlled release of phenolics. When applied to olive oil packaging, the films reduced color degradation under accelerated aging, indicating improved photo-oxidative stability. Composting tests suggested the biodegradation capability of the developed materials under the evaluated conditions. Overall, the study demonstrates an integrated sustainable approach combining waste valorization, active packaging development, and accessible analytical innovation.

The olive oil industry generates large amounts of by-products, particularly olive pomace and olive mill wastewater, which represent valuable sources of polyphenolic compounds with well-recognized antioxidant, anti-inflammatory, antimicrobial, and health-promoting properties. Within the framework of the circular economy, the valorization of these olive-derived residues has emerged as a promising strategy for converting low-value waste into high-added-value ingredients for food, pharmaceutical, and cosmetic applications. This review provides a comprehensive overview of recent advances in sustainable extraction and sample preparation approaches for the recovery of olive polyphenols, including ultrasound-, microwave-, enzyme-, and membrane-assisted technologies, as well as the use of green solvents and environmentally friendly extraction systems. Furthermore, the review discusses advanced analytical strategies for the identification and quantification of olive-derived polyphenols, covering chromatographic, spectrometric, electrophoretic, and miniaturized analytical platforms. Special attention is given to biopolymer-based encapsulation systems developed to enhance stability, controlled release, bioaccessibility, and bioavailability of these bioactive compounds. Finally, current challenges and future perspectives regarding the integration of green extraction technologies, analytical methodologies, and advanced delivery systems are highlighted to promote the sustainable exploitation of olive by-products within a circular economy framework.

Eco-friendly packaging for functional foods aims to reduce environmental impact while maintaining product integrity and ensuring consumer safety. Both the food industry and consumers must transition toward packaging solutions that are sustainable, biodegradable, and non-toxic. Among the key benefits of using environmentally friendly materials for functional food packaging are their sustainability, growing consumer preference, and regulatory compliance. Functional foods are products that offer health benefits beyond basic nutrition, such as enhancing immunity, improving digestion, or promoting overall well-being. This review emphasizes that the packaging of functional foods using an eco-friendly design approach is aligned with the Sustainable Development Goals and the consumers’ preferences. It included the definition and regulatory framework of functional foods, the bioactivity and health effects of bioactive compounds/microorganisms, packaging requirements and solutions for functional foods, as well as conventional and innovative analytical techniques for bioactive compound analysis. Eco-friendly packaging for functional foods is environmentally vital for waste reduction, socially crucial for meeting conscious demand, and economically sound for driving sustainable innovation and green markets.

Food powders were produced from olive pomace (Coratina, COP, and Arbequina, AOP) using freeze-drying with maltodextrin (MD) and native corn starch (NS) as wall materials in varying proportions. Optical microscopy revealed that OP was partially recovered by MD and NS. COP presented a total polyphenol content (TPC) of 53.8 g GAE/kg; meanwhile, AOP was 31.9 g GAE/kg. Accordingly, powders obtained from COP presented higher TPC than those from AOP. NS allowed obtaining powders with higher TPC and antioxidant activity. The greatest encapsulation efficiency was achieved by using 15% MD, achieving values of 94.9% for COP and 89.4% for AOP. Hydroxytyrosol was identified as the predominant polyphenol in the powders. It was demonstrated that powders could be added to food formulations and withstand cooking temperatures up to 220 °C without suffering a significant thermal degradation. Chemometric analysis of MIR and NIR spectra evidenced that they are analytical techniques capable of differentiating OP varieties and wall material types, besides variations in OP concentration. Results derived from this study demonstrated that it is feasible to give added value to olive pomace, obtaining powders rich in antioxidants to be used as ingredients of functional foods.

One of the main goals of green chemistry is to reduce the use of toxic materials and the generation of hazardous waste, both during method development and in the synthesis of the materials used. Thus, a biodegradable, single and reusable material composed of agarose and multi-walled carbon nanotubes was proposed. The film preparation was carefully optimized in order to obtain a one-piece sorbent, with high extraction efficiency and the possibility of reuse. The film was tested in the simultaneous extraction and preconcentration of three non-steroidal anti-inflammatory drugs (ketorolac, ketoprofen and piroxicam) from environmental water samples. The optimal extraction parameters were as follows: isopropyl alcohol as the activation solvent, a sample pH value of 3.0, extraction time of 30 min, 2.00 mL of acetonitrile as the eluent, an elution time of 5 minutes, and a sample volume of 250.00 mL. Under these conditions, the film was reusable 50 times without losing its extraction capacity significantly. HPLC with a photodiode array detector was used for the separation and determination. The method presented a linear range between 0.10 and 1.2 μg L⁻¹, good sensitivity with limits of detection between 0.0075 and 0.0089 μg L⁻¹, and quantification between 0.025 and 0.030 μg L⁻¹. In addition, low RSD values (0.46–3.13%) were obtained demonstrating satisfactory precision. Stream water samples were analyzed, and recoveries between 82.0 and 109.0% were obtained.

Para Red (PR) and Sudan dyes have been illegally used as colorants to adulterate certain foods by enhancing their red/orange colour. In addition, they are toxic and carcinogenic. This work presents the development of a simple flow injection chromatographic method combined with chemometric tools to perform the determination of PR, Sudan I (SI) and Sudan II (SII) in food samples. The flow chromatographic system consisted of a low-pressure manifold coupled to a reverse phase monolithic column. A Partial Least Square (PLS) model was applied to resolve overlapped absorption spectra registered for each dye at the corresponding retention time. The relative errors of calibration (RMSECV, %) were 0.49, 0.85 and 0.23, and the relative errors of prediction (RMSEP, %) were 1.12, 0.75 and 0.33 for PR, SI and SII, respectively. The residual predictive deviation (RPD) values obtained were higher than 3.00 for all analytes. The method was successfully applied to quantify the dyes in six different commercial spices samples. The results were compared with the HPLC reference method concluding that there were no significant differences at the studied confidence level (α = 0.05). The proposed method can be used to rapidly determine the analytes in a simple, reliable, low-cost and environmentally-friendly manner.