Search Results (107)

Black Chiloe’s giant garlic is a functional food produced by a mild Maillard reaction that contains relevant bioactive molecules like organosulfur compounds (OSCs) and (poly)phenols (PPs). Compared with raw garlic, black garlic has a higher content of PPs and S-allyl cysteine (SAC), a key OSC due to its bioactivities. The objective of the present work was to optimize by chemometric tools a green microwave-assisted extraction (MAE) of SAC and PPs present in black Chiloe’s giant garlic to detect and identify novel bioactive molecules with antioxidant and/or inhibitory activities over cyclooxygenase, α-glucosidase, and acetylcholinesterase enzymes. The MAE factors were optimized using a central composite design, establishing optimal PP and SAC yields at 67 °C, 0% ethanol, 12 min and 30 °C, 40% ethanol, 3 min, respectively. PP and SAC values were 9.19 ± 0.18 mg GAE/g DW and 2.55 ± 0.10 mg SAC/g DW. Applying effect-directed analysis using high-performance thin layer chromatography-bioassay and mass spectrometry, the bioactive molecules present in the MAE extract with antioxidant and inhibitory activities over cyclooxygenase, α-glucosidase, and acetylcholinesterase enzymes were identified as N-fructosyl-glutamyl-S-(1-propenyl)cysteine, N-fructosyl-glutamylphenylalanine, and Harmane. Full article

Thai fermented soybeans (TFSs) contain phytochemicals with anti-diabetic benefits. In this study, an initial non-optimized TFS extract (TFSE) was prepared using a conventional triplicate 80% ethanol extraction method and evaluated for its biological activity. TFSE effectively reversed TNF-α-induced insulin resistance in 3T3-L1 adipocytes by enhancing insulin-stimulated glucose uptake, indicating anti-diabetic potential. TFSE also upregulated the phosphorylation of AKT (a key insulin signaling mediator) and the expression of adipogenic proteins (PPARγ, CEBPα) in TNF-α-exposed 3T3-L1, suggesting the mitigation of adipocyte dysfunction; however, the results did not reach statistical significance. The conventional extraction process was labor-intensive and time-consuming, and to enhance extraction efficiency and bioactivity, the process was subsequently optimized using environmentally friendly microwave-assisted extraction (MAE) in combination with the Box–Behnken design (BBD) and response surface methodology (RSM). The optimized extract (O-TFSE) was obtained over a significantly shorter extraction time and exhibited higher levels of total flavonoids and antioxidant activity in comparison to TFSE, while showing reduced levels of isoflavones (daidzein, genistein, and glycitein) in relation to TFSE. Interestingly, O-TFSE retained similar efficacy in reversing TNF-α-induced insulin resistance and demonstrated significantly stronger α-glucosidase and α-amylase inhibitory activities, indicating its enhanced potential for diabetes management. These results support the use of MAE as an efficient method for extracting functional compounds from TFS for functional foods targeting insulin resistance and type 2 diabetes mellitus. Full article

Background: Avocado (Persea americana) peels account for ~20% of the fruit weight and are rich in bioactive compounds, offering significant revalorization potential. This study optimized the extraction parameters of phenolics using ultrasound- (UAE) and microwave-assisted technologies (MAE) with a Central Composite Design (CCD). Methods: The extraction variables included EtOH concentration (0–100%), temperature (13–47 °C for UAE and 55–95 °C for MAE), and time (3–37 min for UAE and 3–27 min for MAE). Total antioxidant capacity (TAC) and total phenolic compounds (TPC) were measured, while individual phenolics were analyzed via HPLC/MS. Results: EtOH concentration was the most influential variable, with optimal conditions involving 94.55% EtOH and moderate temperatures over short times (45 °C for 5 min in UAE and 67 °C for 12 min in MAE). Both techniques yielded comparable results for effective conditions, though MAE required higher temperatures and longer times. In this sense, the data show that UAE extracted higher concentrations of procyanidins (+15%), demonstrating superior performance using a lower time and temperature, making it more efficient. Conclusions: UAE and MAE effectively extract antioxidants, promoting sustainability in the agri-food sector. Full article

The valorization of agri-food waste has emerged as a global priority. In this context, fruit seed waste is being investigated for oil extraction due to its richness in bioactive compounds with remarkable health benefits. This review (2020–2025) focuses on the current state of eco-friendly extraction techniques for obtaining high-yield oils enriched with compounds such as tocopherols, polyphenols, fatty acids, phytosterols, and carotenoids. A comparison of the present method with conventional extraction techniques reveals several notable distinctions. Conventional methods are generally characterized by prolonged extraction times, elevated temperatures, and high amounts of solvents and/or energy. The findings of this review suggest that the extraction methodologies employed exerts a substantial influence on the yield and bioactive composition of the oil, which in turn affects its health-promoting properties. Furthermore, the results have demonstrated that alternative methodologies (microwave-assisted extraction, ultrasound-assisted extraction, pressurized liquid extraction, electric pulse extraction, enzyme-assisted extraction, subcritical extraction, and combinations thereof) have analogous oil yields in comparison with conventional methods. In addition, these oils present a superior bioactive profile with feasible potential in industrial and health applications. The novelty of this work lies in its emphasis on the valorization of fruit seed waste, as well as its sustainable approach. This sustainable approach utilizes experimental design strategies, the implementation of developments that employ comprehensive ecological metrics, and the latest trends in the application of artificial intelligence. Full article

Drying is a key method for food preservation; however, conventional techniques often lead to the degradation of bioactive compounds, compromising nutritional quality. This systematic review, following the PRISMA protocol, examines emerging food drying technologies designed to enhance process efficiency while preserving nutritional and functional properties. A bibliometric analysis was conducted to identify research trends from 2014 to 2024. Searches were performed in the Scopus and Web of Science databases accessed on 17 January 2025, including only original research articles published in English focusing on food drying applications. Reviews, editorials, and studies unrelated to the food sector were excluded. Due to the technological nature of the outcomes, a formal risk of bias assessment was not applicable. This review highlights several emerging drying technologies, such as microwave, radiofrequency, infrared, ultrasound, freeze-drying, and cold plasma. The qualitative synthesis indicates these technologies improve the retention of phenolics, flavonoids, and vitamins, thus enhancing nutritional stability. Nevertheless, challenges remain in industrial-scale implementation, particularly regarding the economic feasibility and optimization of operational parameters. This review received no funding and was not registered in any public database. The findings underscore the need for continued research to develop sustainable and functional dried food products that meet current market demands and consumer expectations. Full article

Coffee pulp, which accounts for approximately 40% of the dry weight of coffee cherries, is one of the many byproducts produced by the world’s most popular beverage, coffee. Such neglected waste represents an interesting source of bioactive compounds, such as procyanidins, which have antioxidant, anti-inflammatory, and neuroprotective properties. This study aims to develop an efficient method for procyanidins extraction from Coffea arabica pulp using a novel microwave–ultrasound hybrid method of extraction. Microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE) and a novel hybrid method (MAE–UAE) were comparatively analyzed. Using Box–Behnken design, the hybrid extraction method was optimized, giving a procyanidin yield of 60.88 mg/g (under these conditions: ~60 °C, ~21 min, ~1:13 solid-to-liquid ratio). The purification was carried out through a Sephadex LH-20 packed column chromatography, and the identified procyanidin dimers and trimers were confirmed by HPLC/ESI-MS. The hybrid extract’s acetonic fraction’s DPPH and ABTS tests revealed that procyanidins had a greater capacity to scavenge radicals than Trolox (p < 0.05). The findings highlight the potential of sustainable extraction methods for valorizing coffee pulp in functional food and pharmaceutical applications. Full article

This paper introduces a flexible loop antenna-based sensor optimized for real-time monitoring of meat quality by detecting changes in dielectric properties over a six-day storage period. Operating within the 2.4 GHz ISM band, the sensor is designed using CST Microwave Studio 2024 to deliver high sensitivity and accuracy. The sensing mechanism leverages resonance frequency shifts caused by variations in permittivity as the meat degrades. Experimental validation across five samples showed a consistent frequency shift from 2.14 GHz (Day 0) to 1.29 GHz (Day 5), with an average sensitivity of $0.173\mathrm{GHz}/\mathrm{day}$. A strong correlation was observed between measured and simulated results, as evidenced by linear regression ($R^2=0.984$ and $R^2=0.974$ for measured and simulated data, respectively). The sensor demonstrated high precision and repeatability, validated by low standard deviations and minimal frequency deviations. Compact, printable, and cost-effective, the proposed sensor offers a scalable solution for food quality monitoring. Its robust performance highlights its potential for integration into IoT platforms and extension to other perishable food products, advancing real-time, non-invasive, RF-based food safety technologies. Full article

Cinnamomum iners Reinw. ex Blume has long been recognized as a plant with food and medicinal uses. This study was designed to optimize the MAE process to produce a high-value, polyphenol-rich crude extract from cinnamon leaves (PCL). The primary goal was to apply response surface methodology (RSM) with a face-centered central composite design (FCCD) to identify the ideal conditions for microwave-assisted extraction (MAE). Key factors such as the MAE time, microwave power, and solid-to-liquid ratio were examined to produce a polyphenol-rich crude extract from C. iners leaves. The resulting extracts were assessed for extraction yield, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity. The results showed that MAE using a methanol solvent had a significant impact on antioxidant compound levels. The R² values for all responses, yield, TPC, TFC, and DPPH radical scavenging activity were 0.9497, 0.9494, 0.9199, and 0.9570, respectively, indicating that the developed quadratic polynomial models were accurate and suitable for analyzing MAE parameter interactions. The optimum MAE parameters were determined to be an MAE time of 25 min, microwave power of 214.24 W, and plant leaf–solvent ratio of 1:195.76 g/mL. In these optimized MAE conditions, the predicted extraction yield, TPC, TFC, and IC₅₀ of DPPH scavenging were 18.56%, 22.86 mg GAE/g, 13.89 mg QE/g, and 83.30 µg/mL, respectively. The enhanced efficiency of MAE comes from microwave-induced heating, which disrupts cell walls for faster compound release, making it more effective and time-efficient than traditional HRE for polyphenol extraction. This study demonstrated that polyphenols can be efficiently extracted from C. iners using MAE, producing a valuable extract with potential as a natural preservative in food and a skin-protective, anti-aging ingredient in cosmetics. Full article

The intake of mushrooms provides numerous beneficial properties for the correct functioning of the human body due to their rich content in carbohydrates, proteins, fibers, vitamins, and minerals. However, most of the reports are focused on the determination of bioactive compounds and only a few regarding the essential mineral content and the evaluation of the RDI. Thus, the aim of this study was to determine the mineral composition of different cultivated (A. bisporus and P. ostreatus) and wild edible mushrooms (A. crocodilinus, A. arvensis, A. silvicola, A. impudicus, M. mastoidea, M. rhacodes, and P. ostreatus) collected in the south of Spain and north of Morocco. First, the optimization of a microwave-assisted digestion method was carried out using a Box–Behnken design with a response surface methodology to quantify the total content of five metals: Fe, Mg, Na, K, and Ca in mushrooms. The samples were analyzed by FAAS and ICP-OES. The percentage of the RDI of each mineral covered by the intake of mushrooms was calculated. It was observed that a high percentage of RDI levels are covered and just exceeded for Fe. Thence, due to their beneficial properties and high content of essential minerals, mushrooms would be proposed as a valuable source of nutrients to manufacture some food supplements. Full article

The purpose of the present study was to compare the polyphenolic compounds extracted from five Sideritis species grown in Greece; S. scardica, S. clandestina, S. raeseri, S. euboea, and S. syriaca, using the Microwave-Assisted Extraction (MAE) process. To maximize the extraction yield (EY), total phenolic compounds (TPC), hypolaetin (HYP) and isoscutellarein (ISC), derivative contents (target phenolics), the response surface methodology was used for S. scardica. A Box–Behnken design was undertaken to study the effect of ethanol concentration (30–100%), extraction temperature (40–100 °C), and extraction time (5–25 min) on the responses. The optimal MAE parameters were 87.9% (v/v) ethanol, 25 min, and 100 °C. Under these conditions, there was a good agreement between experimental and predicted values, indicating the reliability of the predictions for Sideritis extracts. Phenolic compounds were then extracted under these conditions, from the five Sideritis species under investigation. The TPC, total flavonoid content (TFC), antioxidant activity based on DPPH, ABTS, and FRAP assays as well as the phenolic profile of different Sideritis extracts, evaluated via HPLC-DAD-MS, were compared. A similar phenolic profile was observed among the five Sideritis species, with HYP and ISC derivatives showing variations in their contents as a function of Sideritis species. MAE Sideritis extracts could be considered green and natural antioxidants for medicinal, cosmetic, and food purposes, accompanied by sustainable approaches. Full article

This research presents the development and analysis of a microwave sensor designed with a microstrip band-stop filter, aimed at applications in electrical engineering and food quality assessment. The sensor employs parallel-coupled lines within the microstrip, integrating a band-stop filter at 2.45 GHz on an FR4 substrate. The primary objective is to evaluate preserved fish samples to demonstrate the sensor’s efficacy and applicability. Measurements were conducted using a KEYSIGHT model E5063A network analyzer, covering a frequency range from 0.1 GHz to 3 GHz. The analysis focuses on the frequency response of the insertion loss (S₂₁) across specified frequencies. The results indicate a significant correlation between the percentage shift in the transmission coefficient and the frequency, even when the sample range was meticulously adjusted. These findings underscore the potential of microwave sensors in monitoring the physical properties of preserved food, particularly within food production and quality control processes. The sensor facilitates rapid and precise assessments of food properties, highlighting its broad applicability in various sectors of the food industry. Furthermore, this research contributes to the advancement of microwave technology, suggesting new pathways for future studies and applications in engineering and industrial contexts. The integration of microstrip technology with band-stop filters in sensor design presents a novel approach that enhances the accuracy and efficiency of food quality monitoring systems. This study not only establishes a foundation for further technological developments but also emphasizes the interdisciplinary nature of modern engineering solutions, combining principles of electrical engineering with practical applications in the food industry. This innovative approach could lead to more sophisticated and reliable methods for ensuring food safety and quality. Full article

Carminic acid is a natural pigment typically found in several insect taxa, including specific insects such as “grana cochinilla fina” in Mexico (Dactylopius coccus Costa). Commercially, it is also referred to as carmine, which is a more concentrated solution presenting as at least 50% carminic acid. To date, this dye has been used in the pharmaceutical, food and cosmetic industries. Unfortunately, one of the main limitations has to do with establishing the appropriate extraction and purification protocol. Currently, there is growing interest in developing eco-friendly and efficient pigment extraction processes for various applications. In this study, we compare the ultrasound- and microwave-assisted extraction versus with a conventional method to obtain carminic acid from cochineal. To do this, we considered three factors that influence the extraction process as independent variables: solvent volume, temperature and irradiation time. The optimization was carried out using the response surface methodology, employing a three-factor and three-level Box–Behnken experimental design. Carminic acid contents were quantified by UV–Vis spectroscopy, and extracts were evaluated by infrared spectroscopy to verify the integrity of the carminic acid molecule. The yield obtained by ultrasound-assisted extraction was 49.2 ± 3.25, with an efficiency of 31.3 mg/min, while microwave-assisted extraction showed a yield of 40.89 ± 2.96, with an efficiency of 27.3 mg/min. Both methods exceeded the extract yield (31.9 ± 3.4%) and efficiency (10.6 mg/min) obtained with the conventional method, demostrating that ultrasound- and microwave-assisted extraction are viable alternatives for obtaining carminic acid, with the potential to be scaled up to an industrial level. Full article

Industrial microwave-heating systems are pivotal in various sectors, including food processing and materials manufacturing, where precise temperature control and safety are critical. Conventional systems often struggle with uneven heat distribution and high fire risks due to the intrinsic properties of microwave heating. In this work, a fiber-optic-sensor-assisted monitoring system is presented to tackle the pressing challenges associated with uneven heating and fire hazards in industrial microwave systems. The core innovation lies in the development of a sophisticated fiber-optic 2D temperature distribution sensor and a dedicated fire detector, both designed to significantly mitigate risks and optimize the heating process. Experimental results set the stage for future innovations that could transform the landscape of industrial heating technologies toward better process quality. Full article

The global consumption of dried mushrooms has increased worldwide because of their rich nutritional value and culinary versatility. Dehydration methods such as sun drying, hot air drying, freeze drying, and microwave drying are employed to prolong the shelf life of a food product. These methods can also affect the food product’s nutritional value and the final product’s microbial profile. Each technique affects the retention of essential nutrients like vitamins, minerals, and bioactive compounds differently. Additionally, these techniques vary in their effectiveness at reducing microbial load, impacting the dried mushrooms’ safety and shelf life. This review addresses the gap in understanding how different dehydration methods influence dried mushrooms’ nutritional quality and microbial safety, which is crucial for optimizing their processing and consumption. It targets researchers, food processors, and consumers seeking to improve the quality and safety of dried mushrooms. This review comprehensively examines the impact of major dehydration techniques, including sun drying, hot air drying, microwave drying, and freeze drying, on the nutritional and microbial profiles of dried mushrooms. Each method is evaluated for its effectiveness in preserving essential nutrients and reducing microbial load. Current research indicates that freeze drying is particularly effective in preserving nutritional quality, while hot air and microwave drying significantly reduce microbial load. However, more well-designed studies are needed to fully understand the implications of these methods for safety and nutritional benefits. These findings are valuable for optimizing dehydration methods for high-quality dried mushrooms that are suited for culinary and medicinal use. Full article

Herbs and spices, with their wealth of bioactive compounds, are widely used in food, medicine, and cosmetics. Among them, coriander (Coriandrum sativum L.) is particularly valued for its medicinal and culinary properties. Growing consumer and industrial interest in natural products has led to the development of modern, environmentally friendly extraction techniques designed to improve the yield and quality of extracts while reducing time, energy, and solvent consumption. These processes make it possible to obtain optimal quantities of active compounds, thereby meeting the growing demand for plant-based products. After showing evidence of coriander’s health benefits, this review summarizes research findings on the impact of some treatments and pretreatments on its phytochemical composition. After that, it summarizes different aspects of the use of conventional and non-conventional extraction techniques for coriander’s bioactive constituents, mainly polyphenols and crude and essential oils (EO). Among these methods, microwave-assisted extraction (MAE/MAHD) emerges as one of the most efficient methods, offering higher yields, better-quality extracts, and a significant reduction in energy costs. Full article