Ex situ conservation of plant biodiversity has been increasingly used to prevent further loss of genetic resources. Seed banks, for example, shelter the passport data of germplasm, preserved in ...detail, and made available for easy access, actions included in the FAO’s Second Global Plan. We examined the deterioration of tomato seeds of different varieties stored for 10-year intervals at COMAV’s genebank. Samples were analyzed using the conventional Germination and Tetrazolium tests, as well as the non-conventional Differential Scanning Calorimetry and Fourier Transform Infrared Spectrometry techniques, to quickly identify the physiological status of the accessions. Fatty acid profile was also determined. The relationship observed between lipid behavior and seed deterioration under long time storage conditions was the same for both non-conventional and conventional techniques. The viability of the samples was not affected by storage time, however, all the employed methods permitted identifying differences between varieties or accessions of the same variety. The complementary methods helped us interpret a complex data set with many interacting factors, leading to rapid identification of seed quality, increasing processing efficiency in tomato seeds conservation.
•Alginate-starch hydrogels are a vehicle for natural antioxidant delivery in foods.•Starch addition improved encapsulation efficiency of calcium alginate beads.•Encapsulated polyphenols were totally ...recovered after passing digestive model fluids.•Yerba mate polyphenols were released by diffusion and erosion mechanism.
A liquid extract of yerba mate (Ilex paraguariensis), with antioxidant properties was encapsulated in calcium-alginate hydrogels containing corn starch as filler at different concentrations. Hydrogel beads were characterized for morphological and size aspects, encapsulation efficiency, Fourier Transform Infrared Spectrometry (FT-IR) and thermal behavior. Addition of starch improved the encapsulation efficiency from 55 to 65%. In vitro release of polyphenols was analyzed in model gastric and intestinal media. The recovery of encapsulated polyphenols occurred mainly in the simulated gastric fluid (85%). Kinetics and release mechanism were satisfactorily fitted to semi-empirical models. The incorporation of starch filler (2g/100mL) in calcium alginate hydrogels modified the release profile of polyphenols in acidic medium. In calcium alginate beads, a release mechanism combining erosion and diffusion was observed. Whereas, for polyphenols release of starch loaded beads, only diffusion was relevant.
Calcium lactate, magnesium sulphate and yerba mate (
Ilex paraguariensis) extracts with antioxidants properties were encapsulated by co-crystallization in a supersaturated sucrose solution. ...Solubility, hygroscopicity, bulk density, water activity (
a
w), particle size distribution and repose angle of co-crystallized products were determined. The surface structure analysis of the co-crystallized products was performed by scanning electron microscopy (SEM). The concentration of mineral components in co-crystallizates was quantified by a volumetric titration method with EDTA (ethylenediaminetetraacetate); Folin–Ciocalteau method was used to determine total polyphenols of yerba extract in co-crystallized products. Size distribution, solubility, density and flow properties strongly depended on sucrose matrix, whereas hygroscopicity and
a
w varied with the active component.
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•Room-temperature extraction methods achieved a similar chia oil yield to Soxhlet.•Extraction method did not greatly affect genuine and quality indexes of chia oils.•FT-IR and DSC ...were fast methods to characterize the quality of chia oil.•Lipid extraction by Biondós method was the most proper for seed aging studies.
Lipids are relevant during the seed aging process, for which it is pertinent to choose an extraction method that does not alter their nature. Thus, three methods were applied to extract lipids from chia seeds: one used as reference (Soxhlet) and two at room temperature using hexane/ethanol (COBio) and hexane/isopropanol (COHar). The fatty acid composition and the tocopherol content of the oils were analyzed. Also, their oxidative status through the peroxide index, conjugated dienes and trienes, and malondialdehyde were determined. Besides, biophysical techniques, such as DSC and FT-IR, were applied. The extraction yield was not affected by the extraction method, while the fatty acid composition presented slight differences. Despite the high content of PUFAs, the oxidation level was low in all cases, especially in COBio, associated with the high content of α-tocopherol. DSC and FT-IR outcomes coincided with those obtained by conventional studies, resulting in efficient and fast characterization tools.
Understanding aging in seeds is vital for conservation and long-term preservation. This study examined the physiological and lipid characteristics of three chia varieties (WN, MNI, MNII) using ...conventional and biophysical methods to establish correlations and explore aging mechanisms. Variables assessed included thousand seed weight, moisture content (MC), and germination parameters, such as normal germination power (NGP), hypocotyl and radicle length, vigor, viability, as well as lipid characteristics, and thermal parameters. Physiological differences were prominent, especially in the MNII, with longer mean germination times (MGT = 2.11 d) and reduced NGP (63.24%). The WN variety exhibited superior germination (NGP = 95.9%), while MNI had an NGP of 93.2% and the highest vigor. Lipid analysis revealed significant differences, particularly in free fatty acid content (FFA). The oxidative status and tocopherol content were evaluated, with high germination in WN being associated with the combination of tocopherol isomers. The thermal analysis highlighted the predictive potential of ΔH for seed health and viability. Spectral analysis distinguished nutlets and oils, showcasing unique vibrational patterns. The correlation analysis revealed significant relationships crucial for conservation. MGT showed positive correlations with moisture content, electrical conductivity, and FFA, but negative correlations with germinated nutlets (GN) and normal seedlings (NS). MC positively correlated with FFA, abnormal seedlings (AS), and deteriorated nutlets, yet negatively correlated with GN and NS. Electrical conductivity emerged as a germination indicator, positively correlating with FFA and deteriorated nutlets, and negatively with GN and NS. δ-tocopherol content positively correlated with successful germination and NS, but negatively with AS. Thus, this research provides relevant knowledge on the conservation of chia nutlets by offering information on seed deterioration markers that can be obtained by FT-IR and DSC. This is particularly valuable for studying germplasm with a limited sample size, common in gene banks.
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•Physiological, biochemical, and biophysical changes were compared for different chia genotypes.•All physiological properties exhibited suboptimal values for the MNII cultivar.•Free fatty acids proved to be a reliable indicator of nutlets deterioration.•The fusion energy determined by DSC correlated with the degree of deterioration.•PCA analysis of FT-IR separated cultivars with different physiological performances.
Betacyanins are betalain derivatives showing a red-violet color suitable as a natural food colorant. An aqueous extract rich in betacyanin pigments and phenolic compounds from Alternanthera ...brasiliana was characterized using a high-performance liquid chromatography system with diode array and electrospray mass spectrometry detection. The major betacyanins (amaranthine, isoamaranthine, betanin and isobetanin, celosianin II and isocelosianin II) were identified and quantified. Eleven peaks were analyzed for phenolic compounds grouped into hydroxycinnamic acids and flavones. Different plant extract concentrations were added to freshly prepared set type yogurts (350, 700, and 1400 μL/80 g yogurt). Color properties in CIELAB space, pH, total phenolic content, and ferric reducing antioxidant power were analyzed on yogurts during storage time. The evolution of pigments and polyphenolic compounds during cold storage was studied by HPLC-ESI-QTOF-MS screening.
The extracted color showed to be stable at the yogurt pH range. When added to yogurts, a natural berry-like color was achieved. These results provide a natural plant pigment-based alternative for application in food products, being the first time that A. brasiliana is used as a colorant in a dairy product. Besides color, polyphenols input turns Alternanthera brasiliana extract into a desirable functional food ingredient.
•Betacyanin and phenolic compounds were found in A. brasiliana aqueous extract.•Aqueous extract was added into yogurts to dye and functionalize them.•Pigments and phenolic compounds were tested by HPLC-ESI-QTOF-MS during cold storage.•The aqueous extract color was stable (4–11 pH range) during 21 days of cold storage.•Correlations were noted between measured a* and b* color parameters and yogurt pH.
•Yerba mate liquid extract was converted to free-flowing powder by co-crystallization.•Powders with a high loading capacity of yerba mate polyphenols were obtained.•Antioxidant activity of the yerba ...mate extract was not affected by the process.•Co-crystallization is an alternative to protect the antioxidants during storage.•Yerba mate powders could be used as an natural antioxidant in food formulations.
The interest on yerba mate has increased in the last years due to its high content of bioactive compounds related to health benefits. Antioxidant aqueous extracts of yerba mate were entrapped into a sucrose matrix by co-crystallization. The products were characterized in terms of their morphology, entrapment yield, loading capacity, water activity, moisture content, antioxidant activity, thermal behavior, solubility and hygroscopicity. It was found that the co-crystallization process led to high entrapment yield and maintained the antioxidant activity of the yerba mate extract towards DPPH radical. Also, the co-crystallized powders showed values of water activity, moisture content, hygroscopicity and flowability indicative of high stability and good handling properties. The total polyphenols content of the co-crystallized products remained almost constant along storage at 75% RH and 20°C, however, fluctuations in their DPPH radical scavenging activity were observed.
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•Ca(II)-alginate with yerba mate powder were efficient to encapsulate N, P and K.•Phosphorous precipitation as calcium phosphate provoked many structural changes.•Urea and phosphorous ...release in water was a diffusion-governed process.•Degradation in soil and thermal properties were determined by matrix components.•Slow release of Ca2+ from the phosphate crystals generate thin and compact rods.
Yerba mate (Ilex paraguariensis) is an infusion traditionally drunk in many countries of South America. Along its industrial manufacture, a fine yerba mate powder represents a considerable proportion of the total production, consisting of an industrial by-product not safe for human consumption, rich in minerals, that could be useful as organic compost. In line with current bioeconomic trends, here we present the recycling of yerba mate industrial by-products into urea, potassium and phosphate-containing capsules as an environmentally friendly strategy for the design of controlled-release fertilizers. The capsule matrix is based on Ca(II)-alginate with a final yerba mate powder (YMP) content of 83% w/w. The aim of this work was to study the kinetics of mineral fertilizers release both in soil and water, along with an exhaustive macro and microstructural characterization (PIM, DSC, TGA, SEM-EDX, X ray scan tomography and SAXS) to allow the analysis of structure/function relationships. The encapsulation efficiency and release in water of phosphorous were affected, being significantly lower than urea and potassium and releasing under different mechanism. Retention and degradation in soil was mainly related to capsule structure, as well as their thermal properties. The incorporation of different fertilizer induced structural changes in Ca(II)-alginate network as assessed by SAXS.
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