Freezing is an effective technology with which to maintain food quality. However, the formation of ice crystals during this process can cause damage to the cellular structure, leading to food deterioration. A good understanding of the relationship between food microstructure and ice morphology, as well as the ability to effectively measure and control ice crystals, is very useful to achieve high-quality frozen foods. Hence, a brief discussion is presented on the fundamentals/principles of optical microscopic techniques (light microscopy), electronic microscopic techniques (transmission electron microscopy (TEM) and scanning electron microscopy (SEM)), as well as other non-invasive techniques (X-rays, spectroscopy, and magnetic resonance) and their application to measuring ice formation rates and characterizing ice crystals, providing insight into the freezing mechanisms as well as direct monitoring of the entire process. And, in addition, this review compares (the negative and positive aspects of) the use of simple and cheap but destructive technologies (optical microscopy) with detailed microscopic technologies at the micro/nanometer scale but with pretreatments that alter the original sample (SEM and TEM), and non-destructive technologies that do not require sample preparation but which have high acquisition and operational costs. Also included are images and examples which demonstrate how useful an analysis using these techniques can be.

This research aimed to evaluate block freeze concentration (BFC) under different centrifugation conditions using response surface methodology to separate an extract from the ice fraction at three centrifugal-BFC (CBFC) cycles, obtaining in the final cycle a phenolic-rich extract. A Box–Behnken design was applied to optimize centrifugation variables, with efficiency of separation (η) selected as the response variable. The extracts were characterized in terms of physicochemical analysis, total and individual bioactive components, and antioxidant capacity. Optimal conditions (3600 rpm, 16 °C, and 14 min) resulted in η of 82%. Thus, from infusion to final cycle, the solids, total polyphenol and flavonoid contents, and antioxidant capacity exhibited from 1.81 to 6.5% (w/w) and 2.5 to 8.7 (°Brix), 0.72 to 12.2 mg gallic acid equivalents/mL, 0.83 to 13.7 mg catequin equivalents /mL, 2.8 to 31.2 μmol trolox equivalents/mL and 4.8 to 122.2 μmol trolox equivalents/mL, identifying by high-performance liquid chromatography that kaempferol, p-hydroxybenzoic, and transferulic acid presented the highest concentrations. The CBFC process has the potential as a non-thermal concentration process to preserve many bioactive compounds, facilitating the production of concentrated fractions with high biological value, where the extracts obtained by BFC are a novel solution for medicinal, pharmaceutical, and food applications.

Gummies have evolved from traditional confectionery products into hydrogel-based systems capable of incorporating and releasing bioactive compounds. This review examines the main formulation and technological factors governing their structure and functionality, with an emphasis on the use of hydrocolloids, alternative sweetening systems, and molecular interactions, the incorporation of bioactives, and the recent use of emerging technologies in their production. The literature was retrieved from Scopus, Web of Science, ScienceDirect, and Google Scholar, encompassing studies published between 2005 and August 2026. The literature shows that the type of hydrocolloid and the sweetener composition strongly influence gel formation, water mobility, hydrogen bonding, crystallization, texture, and storage stability. Plant byproducts, extracts, and marine-derived ingredients provide additional sources of bioactive compounds, while microencapsulation, nanoencapsulation, high-pressure processing, cryoconcentration, ultrasound, and 3D printing offer opportunities to enhance their protection and release. However, interactions between bioactive compounds and the gel matrix can affect texture, sensory acceptance, stability, and bioaccessibility. Therefore, developing functional gummies requires a comprehensive understanding of formulation, hydrogel structure, processing conditions, and bioactive stability to obtain products with suitable technological, sensory, and functional properties.

The objective of this study was to evaluate the application of centrifugal block freeze concentration (CBFC) in fresh almond milk to obtain a concentrated liquid sample with enhanced chemical composition, total bioactive compounds (TBC), antioxidant activity, and process parameters, preserving its physicochemical characteristics. As the cycles progressed, the chemical composition (protein and lipid content), TBC (total polyphenol, flavonoid and protein (albumin) content), and antioxidant activity (2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC)) significantly increased, reaching 5.2% and 3.3%, 3.16 mg gallic acid equivalents/100 mL, 0.2 mg catechin equivalents/100 mL, 33.5 mg albumin/100 mL, and 55.9, 71.4, and 65.1 µM Trolox equivalents/100 mL, respectively. The separation efficiency and solute yield reached values close to 87% and 72%, respectively. In solute terms, a significant threefold was noted, maintaining an attractive color very similar to that of the fresh sample. Thus, CBFC is an efficient low-temperature concentration method for liquid foods, with lower degradation of TBC than evaporation technology. Hence, the concentrated sample has potential for applications as a functional food and nutraceutical ingredient due to its increased TBC and antioxidant capacity, while its preserved physicochemical stability and chemical composition also suggest feasibility for cosmetic formulations.