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Okra is a common vegetable in the African cuisine, known for its distinctive slimy texture. Plant cell walls include hydrocolloids, especially pectin, which contribute to their sliminess. This textural property is known to become lost during thermal treatment. In this research, okra hydrocolloid is extracted and used to produce a model medium at a pH of 6.0, representing okra's natural state. This medium is subjected to various controlled thermal treatments (70–130 °C) to evaluate their impact on pectin degradation. At the same time, the texture of okra puree is also assessed using an instrumental method under the same conditions. The two main products of pectin degradation—reducing end sugars from depolymerization and methanol from a demethylation—are measured and found to show an increase as a function of time and temperature. Kinetic modeling indicates that a first-order reaction fits well with the experimental concentrations of both products. The rate constants, as a function of temperature, aligns with the Arrhenius model, confirming the chemical basis of the degradation. Instrumental results correlate well with the production of methanol and reducing end sugars, indicating that pectin degradation is the primary cause of texture changes during the thermal treatment of okra and that this change can be controlled by adjusting the temperature. [ABSTRACT FROM AUTHOR]

This work investigated the coupling of microfiltration (MF) and nanofiltration (NF) to concentrate the volatile compounds in a raspberry hydroalcoholic extract. Enzymatic treatment increased the MF permeate flux by 30%–50%. The highest MF permeate flux was above 50 kg·h−1·m−2 at a mass reduction ratio of 5. MF allowed efficient clarification of the extract without significant retention of aroma compounds. Among the NF membranes tested using the MF permeate as feed, one membrane was clearly more effective in concentrating the extract in terms of flux (19 kg·h−1·m−2 at 35 bar), retention of aroma compounds (average retention of 85%), phenolic compounds (61%) and dry matter (90%). Three other membranes were of interest for the fractionation of volatiles in both permeate and retentate but with a lower permeate flux. Finally, one membrane retained few aroma compounds but showed 70% dry matter retention, making it a promising method for aroma purification versus dry matter content in the permeate. Practical Applications: In this study, we investigated the coupling of crossflow MF and NF with a pectinolytic pretreatment, in order to concentrate the aroma compounds from a raw organic raspberry extract. The aim was to avoid aroma degradation and reduce the operating costs, compared to the conventional concentration thermal technologies. Few authors have studied aroma concentration by NF, which presents an interesting area of research for industrial applications. This work provides keys for flavor manufacturers to add value to their products at a low cost and with limited environmental impact, producing concentrated natural aroma extracts for food. Another originality of this work for industrial companies was to show that thanks to the same process, several fractionations could be achieved simply by modifying the operating conditions. Therefore, this work contributed to propose new applicable processing for the production of natural flavors in a context of high consumer and market demand for organic ingredients. [ABSTRACT FROM AUTHOR]

Aleppo pine seeds are a potential candidate for the production of nondairy milk due to their high protein (26%) and lipid (37%) content and their availability. For the first time, this study presents the implementation of a manufacturing scheme from seeds to final product, including pre‐extraction, extraction, and post‐extraction (physical and microbiological stabilization), using a 2(7‐4) fractional factorial screening design. The seven factors were seed soaking time, grinding time, temperature and seed/water ratio during extraction, xanthan gum concentration, homogenization pressure, and pasteurization temperature. Beverage quality analysis consisted of measurements of chemical composition, color, stability, and rheological behavior. The results of experimental design showed that the dry matter as well as the lipid and protein contents increased significantly by increasing the ratio (grain/water) and the grinding time. On the other hand, the extraction temperature led to a better extraction of lipids but a lower extraction of proteins. Regarding stability, xanthan gum had a negative effect, while homogenization pressure and pasteurization temperature showed their effectiveness in decreasing the particle size and increasing the physical stability of the product. Practical applications: Plant‐based drinks, also called plant milks, are interesting alternatives to animal milk. They have similar organoleptic properties but are more sustainable and offer very different nutritional composition depending on the plant used. As the consumers demand is constantly increasing, setting up fabrication processes from new plant sources is relevant. Aleppo pine seeds are a potential matrix for the production of vegetable beverages because they are very nutritious and available in the entire Mediterranean area. This study presents the setting up of a fabrication diagram of a plant‐based beverage made from Aleppo pine seeds. Seven production parameters were tested, including pre‐extraction (seed conditioning), extraction, and post‐extraction (physical and microbiological stabilization), thanks to a fractional factorial 2(7‐4) screening design. The best conditions enabled the production of a final beverage comparable to other commercialized plant‐based beverages in terms of nutritional and organoleptic quality. [ABSTRACT FROM AUTHOR]