Two different extraction methods were used for a comparative study of Algerian Myrtle leaf essential oils: solvent-free-microwave-extraction (SFME) and conventional hydrodistillation (HD). Essential oils analyzed by GC and GC-MS presented 51 components constituting 97.71 and 97.39% of the total oils, respectively. Solvent-Free-Microwave-Extract Essential oils SFME-EO were richer in oxygenated compounds. Their major compounds were 1,8-cineole, followed by α-pinene as against α-pinene, followed by 1,8-cineole for HD. Their antimicrobial activity was investigated on 12 microorganisms. The antioxidant activities were studied with the 2,2-diphenyl-1-picrylhydrazyl (DPPH^•) radical scavenging method. Generally, both essential oils showed high antimicrobial and weak antioxidant activities. Microstructure analyses were also undertaken on the solid residue of myrtle leaves by Scanning Electronic Microscopy (SEM); it showed that the SFME-cellular structure undergoes significant modifications compared to the conventional HD residual solid. Comparison between hydrodistillation and SFME presented numerous distinctions. Several advantages with SFME were observed: faster kinetics and higher efficiency with similar yields: 0.32% dry basis, in 30 min as against 180 min for HD.

While the use of “puffing” process is mainly limited to products like cereals or carrot, the instant controlled pressure drop (DIC) can treat and expand the large domain of heat sensitive food products. In the present article, this operation is applied on partially dried apple and onion, to produce snack or, by shadow grinding, expanded granule powder. DIC is a high-steam pressure treatment (up to 0.6 MPa in this article), where steam is applied constantly during a short treatment time t (5–55 s) and instantaneously dropping the pressure toward vacuum 5 kPa with a rate higher than 0.5 MPa s⁻¹. The expanded structure allows the product to achieve better functional properties linked with a greater specific surface area. Thus, the time of final hot air drying (with air flow at 40°C, 1 m s⁻¹, and 267 Pa partially pressure humidity) is reduced by about 55% through greater effective diffusivity and initial starting accessibility. The product's nutritional value is partially preserved (vitamins) or even improved through more available flavonoids. DIC can perfectly decontaminate the products, and end quality attributes are higher than normally dried or as good as freeze-dried fruits.

In the present article, a new manner to use the instant controlled pressure drop (DIC) was adopted in the drying of onion. Instead of using it as a texturing treatment inserted in the second stage of hot air swell-drying operation and performed when water content is less than 30 g H₂O/100 g dry matter, here the DIC was performed as a blanching–steaming pretreatment of fresh cut onion, with a steam pressure of 0.2–0.5 MPa, for 5–15 s, and an instant pressure drop (with a rate > 5 MPa s⁻¹) toward a vacuum of 5 kPa. Afterward, drying was carried out with 40°C, 1 m s⁻¹, and 267 Pa partially pressure humidity hot air. Although this DIC treatment aimed to avoid notable expansion, it could intensify mass transfer, reducing the total drying time, which reached 700 min instead of 3200 min for untreated samples; the effective diffusivity and the initial starting accessibility dramatically increased. Consequently, sensorial and nutritional attributes could be preserved with a perfect decontaminated end product.

Food processing systematically aims at meeting the needs of consumers who are looking for total high quality and perfect food safety. As the various thermal and non-thermal food preservation technologies often affect the natural properties in terms of sensation, flavor, texture, etc., instant controlled pressure drop (DIC) has been conceived as a relevant, innovative process in this field. DIC uses high saturated steam pressure and short duration to provide a new way to expand biological matrices, improve drying, decontaminate, and extract biologically active compounds, among other attributes. Therefore, this review focuses on describing the applications of DIC technology on a wide range of products such as foods and by-products that have been processed both in the laboratory and on an industrial scale. The application of DIC has shown the possibility of a significant leap in quality improvement and cost reduction in the food industry. DIC reduces the drying time of fruits and vegetables, and improves the extraction of essential oils, vegetable oils, and antioxidant components. It also provides strong decontamination, eliminates vegetative microorganisms and spores, and reduces non-nutritional and allergenic components. Over the past 33 years, this technology has continued to expand its food applications and improve its characteristics on an industrial scale. But there are still many food unit operations that can be taken to the next level with DIC.

The goal of this article is to define a new industrial operation called three-stage spray drying that can increase the specific surface area of powder while reducing the amount of fine dust. Because of their compact structure, spray-dried granules have an exchange surface limited to their surface area. We performed experiments inserting the instant controlled pressure drop (DIC®) treatment between the atomization (first stage of spray drying) and the final drying stage. As a high-temperature, short time (HTST) process, DIC treatment expanded granule texture at a rate depending on pore distribution, mesopore volume, and the mean porosity thus generated; the cumulative specific surface area thus induced evolved as a function of the DIC treatment conditions: the higher the DIC steam pressure, the higher the expansion rate. Both specific surface area and mean particle diameter may then simultaneously increase. Technological properties were investigated in order to compare DIC textured powders and conventional spray-dried powders and optimize the treatment; such an optimization can include the rate of decontamination thus generated.

Sustainability is becoming increasingly important in the world we live in, because of the rapid global population growth and climate change (drought, extreme temperature fluctuations). People in developing countries need more sustainable protein sources instead of the traditional, less sustainable meat, fish, egg, and dairy products. Alternative sources (plant-based, such as grains (wheat, rice sorghum), seeds (chia, hemp), nuts (almond, walnut), pulses (beans, lentil, pea, lupins), and leaves (duckweed), as well as mycoproteins, microalgae, and insects) can compensate for the increased demand for animal protein. In this context, our attention has been specifically focused on duckweed—which is the third most important aquatic plant after the microalgae Chlorella and Spirulina—to explore its potential for use in a variety of areas, particularly in the food industry. Duckweed has special properties: It is one of the fastest-growing plants in the world (in freshwater), multiplying its mass in two days, so it can cover a water surface quickly even in filtered sunlight (doubling its biomass in 96 hours). During this time, it converts a lot of carbon dioxide into oxygen. It is sustainable, environmentally friendly (without any pesticides), and fast growing; can be grown in indoor vertical farms and aquaculture, so it does not require land; is easy to harvest; and has a good specific protein yield. Duckweed belongs to the family Araceae, subfamily Lemnoideae, and has five genera (Lemna, Spirodela, Wolffia, Wolffiella, Landolita) containing a total of approximately 36–38 recognised species. Duckweed is gaining attention in nutrition and food sciences due to its potential as a sustainable source of protein, vitamins, minerals, and other bioactive compounds. However, there are several gaps in research specifically focused on nutrition and the bioaccessibility of its components. While some studies have analysed the variability in the nutritional composition of different duckweed species, there is a need for comprehensive research on the variability in nutrient contents across species, growth conditions, harvesting times, and geographic locations. There has been limited research on the digestibility, bioaccessibility (the proportion of nutrients that are released from the food matrix during digestion), and bioavailability (the proportion that is absorbed and utilised by the body) of nutrients in duckweed. Furthermore, more studies are needed to understand how food processing (milling, fermentation, cooking, etc.), preparation methods, and digestive physiology affect the nutritional value and bioavailability of the essential bioactive components in duckweed and in food matrices supplemented with duckweed. This could help to optimise the use of duckweed in human diets (e.g., hamburgers or pastas supplemented with duckweed) or animal feed. More research is needed on how to effectively incorporate duckweed into diverse cuisines and dietary patterns. Studies focusing on recipe development, consumer acceptance, palatability, and odour are critical. Addressing these gaps could provide valuable insights into the nutritional potential of duckweed and support its promotion as a sustainable food source, thereby contributing to food security and improved nutrition. In summary, this article covers the general knowledge of duckweed, its important nutritional values, factors that may affect their biological value, and risk factors for the human diet, while looking for technological solutions (covering traditional and novel technologies) that can be used to increase the release of the useful, health-promoting components of duckweed and, thus, their bioavailability. This article, identifying gaps in recent research, could serve as a helpful basis for related research in the future. Duckweed species with good properties could be selected by these research studies and then included in the human diet after they have been tested for food safety.