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Quantitative analysis of carotenoids has been extensively reported using UV-Vis spectrophotometry and chromatography, instrumental techniques that require complex extraction protocols with organic solvents. Fourier transform infrared spectroscopy (FTIR) is a potential alternative for simplifying the analysis of food constituents. In this work, the application of FTIR with attenuated total reflectance (ATR) was evaluated for the determination of total carotenoid content (TCC) in Cucurbita spp. samples. Sixty-three samples, belonging to different cultivars of butternut squash (C. moschata) and pumpkin (C. maxima), were selected and analyzed with FTIR- ATR (attenuated total reflectance). Three different preparation protocols for samples were followed: homogenization (A), freeze-drying (B), and solvent extraction (C). The recorded spectra were used to develop regression models by Partial Least Squares (PLS), using data from TCC, determined by UV-Vis spectrophotometry. The PLS regression model obtained with the FTIR data from the freeze-dried samples, using the spectral range 920–3000 cm−1, had the best figures of merit (R2CAL of 0.95, R2PRED of 0.93 and RPD of 3.78), being reliable for future application in agriculture. This approach for carotenoid determination in pumpkin and squash avoids the use of organic solvents. Moreover, these results are a rationale for further exploring this technique for the assessment of specific carotenoids in food matrices.

Bee‐pollen is a product collected by bees, gathered for human consumption given its nutritional and bioactive characteristics. However, its external structure is extremely recalcitrant and prevents nutrients and bioactive compounds to be completely digested into the gastrointestinal tract. The aim of this study was to assess enzymatic hydrolysis as a strategy to modify the structure of bee‐pollen and promote the release of compounds. Six different commercial enzymes were used and treatments were evaluated by Differential Scanning Calorimetry and Scanning Electron Microscopy, as well as protein, amino acids, phenolics, flavonoids, and antioxidant activity. The calorimetric analysis showed an increase in the heat flow of hydrolyzed products compared to bee‐pollen. It was also found that proteases improved the protein content of about 13%–18%, phenolics 83%–106%, flavonoids 85%–96%, antioxidant activity up to 68%, and increased all essential amino acids. Finally, a total ranking method established as the best treatment hydrolysis with Protamex. Practical applications Bee‐pollen is an attractive food of plant origin from a nutritional and functional point of view. The modification of its structure through enzymatic hydrolysis increases the availability of compounds that theoretically could be assimilated more easily in the gastrointestinal tract, improving the quality of bee‐pollen as a food resource. The treatment is safe, relatively inexpensive and easy to apply, compared to other bee‐pollen modification strategies such as fermentation.

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Electrospinning was used to produce fibrous membranes, in single and multiple layers, from poly(ε-caprolactone), pullulan, and from mixtures of poly(ε-caprolactone) with potato modified starch and β-glucan. It was possible to obtain single-layer membranes from solutions of pullulan in water, poly(ε-caprolactone) in chloroform, and from mixtures of poly(ε-caprolactone)/β-glucan and poly(ε-caprolactone)/potato modified starch in chloroform. Scanning electron microscopy images showed the formation of ultrathin homogeneous fibers from electrospun poly(ε-caprolactone) and pullulan, whereas the fibers obtained from mixtures of poly(ε-caprolactone)/ β -glucan and poly(ε-caprolactone)/potato modified starch had different sizes and morphologies, as well as irregular microstructures, characterized by the presence of beads. Contact angle analyses showed that pullulan membranes were extremely hydrophilic, while poly(ε-caprolactone) membranes were predominantly hydrophobic. Subsequently, poly(ε-caprolactone)-pullulan-poly(ε-caprolactone) multilayer membranes, with intermediate wettability, were prepared by successive electrospinning steps. Infrared spectroscopy and calorimetric analyses showed the presence of both polymers and the absence of changes in their structure and stability due to electrospinning, indicating adequate compatibility between the two polymers. We foresee that the polyester-polysaccharide multilayer membrane might be used as a biodegradable vehicle for active agents with different hydrophobicity, with applications as food packaging and biocompatible scaffold materials.

Bee-pollen is a product of the hive which has had a growth in consumption in recent years due to the recognition of its nutritional and bioactive potential. However, several reports have shown that the external structure of the grain limits the absorption of nutrients in the human gastrointestinal tract. A structural modification could be achieved through fermentative processes, favoring the release of compounds found inside this food, in addition to obtaining a product with potential probiotic characteristics. The objective of this work was to evaluate how fermentation through the inclusion of yeasts of the species Saccharomyces cerevisiae, bacteria of species Lactobacillus plantarum or a commercial culture Choozit® affeccted such parameters as Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), phenolic compounds, flavonoids and antioxidant activity. The results found that the use of consortia between yeast and lactic acid bacteria significantly increased in such characteristics as total phenolics and antioxidant activity by 31% and 39% respectively. The analysis by DSC showed an increase in the heat flow of the fermented products compared to fresh bee-pollen, which could indicate structural modification caused by the activity of microorganisms, a fact made visible through micrographs obtained by Scanning Electron Microscopy.

This review aims to study the alternatives to conventional industrial starches, describing uncommon sources along with their technological characteristics, processing, and performance on food products. Minor components remaining after extraction play an important role in starch performance despite their low percentage, as happens with tuber starches, where minerals may affect gelatinization. This feature can be leveraged in favor of the different needs of the food industry, with diversified applications in the market being considered in the manufacture of both plant and animal-based products with different sensory attributes. Hydrocolloids, different from starch, may also modify the technological outcome of the amylaceous fraction; therefore, combinations should be considered, as advantages and disadvantages linked to biological origin, consumer perception, or technological performance may arise. Among water-based system modifiers, starches and nonstarch hydrocolloids are particularly interesting, as their use reaches millions of sales in a multiplicity of specialties, including nonfood businesses, and could promote a diversified scheme that may address current monocrop production drawbacks for the future sustainability of the food system.

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