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Purpose. The conversion of waste such as discarded jicama (DJ) to value added starch, offers possibility of local economic development and sustainability. Methods. To evaluate the feasibility of reduced food waste, starch from discarded jicama (DJS) and commercial jicama (CJS) were obtained by a conventional method to compare whether the fact that the discarded product is used influences the yield and characteristics of the starch obtained. Results. Significant differences in extraction yield were obtained, both starches presented a granule size between 1 and 12 µm, a type C diffraction pattern, amylose content around 14%, a gelatinization temperature of 61 °C to DJS and CJS; however, properties such as water solubility index (WSI), swelling power (SP), and pasting did present some differences, WSI and SP are higher for CJS causing a faster gelatinization process than in DJS. Conclusion. There are differences in the characteristics of DJS and CJS, particularly it is suggested that DJ does have a significant impact on the internal structure of the starch granule, on the amylopectin fraction mainly.

The structuring of food is mainly done through a complex set of various food materials, such as proteins, polysaccharides, lipids, minerals, and water. Among these components, proteins and polysaccharides are the most used materials in food processing. In extrusion processing, the molecular interactions between its main components play a synergistic role in the achieved structure by performing specific functions in food that affect the sensory, physicochemical, and functional properties. In this research, food for pet animals based on beans (Phaseolus vulgaris L.), fodder corn (Zea mays L.), polished rice (Oryza Sativa), and polysaccharides as inulin, sodium alginate, and/or a native microbial exopolysaccharide from mining waste, was designed and evaluated. To produce the pellet, a single-screw extruder at 140 rpm and 140°C at the exit zone and the effects of the moisture content [13-18%] and concentration of each polysaccharide [0.3-0.9%] on the physicochemical properties of the food were evaluated. The obtained responses were: 1.16-1.4 for expansion index, 0.8-1.7 g/cm3 for bulk density, 1.5-7.4 g/g for water absorption index, 8.8-12.6% for water solubility index, and 8.8-35 N for hardness. According to the recorded values, native exopolysaccharides can provide better physicochemical characteristics than commercial polysaccharides.

The initial oleogelation process (microstructuring) as well as the formulation are determinant to obtain the desired characteristics in oleogels with potential application in the industry. The microstructuring process in oleogels has been extensively studied by means of techniques highly sensitive to thermal variations, such as differential scanning calorimetry (DSC). However, there are other readily available techniques and equipment that can be employed to perform similar evaluations. Non-isothermal nucleation kinetics by spectrophotometric methods can be used as alternatives to basic crystallization studies in oleogels. Therefore, in this research a comparison of both techniques is presented, highlighting their similarities, advantages and limitations, in the study of the microstructure of oleogels. Oleogels were obtained with a minimum concentration of gelator and another saturated one, using vegetable oils of different degrees of saturation. The crystallization profiles of the oleogels were obtained by DSC, a non-isothermal nucleation kinetics was performed from the molten system and the final microstructure was evaluated by optical microscopy. The Fisher-Turnbull and Avrami model was used to evaluate the behavior during microstructuring. A gap was observed during the crystallization process by DSC which can be evaluated by spectrophotometry. Differences in the microstructuring process were found in both methods due to the temperature ramp used and formulation variables. The results obtained by spectrophotometry indicate that it can be a good alternative, easily accessible in oleogel crystallization studies, when high sensitivity or very specific thermal parameters are not required.

Nowadays, there are great research interest in polyhydroxybutyrate (PHB) recovery protocols that reduce the use of organic solvents and efficiently recover this bacterial biopolymer. The present study reports an extraction protocol assisted by ultrasound, which is a rapid protocol that increases the amount of polymeric matter extracted, reduces the cellular digestion step with sodium hypochlorite and eliminates the use of organic solvents. Likewise, characterization studies by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy (1H NMR), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) demonstrated that the biopolymer recovered by this protocol is PHB homopolymer with a major thermal-resistance and crystalline properties. Besides, in this study are reported the thermic and crystalline differences between the PHB obtained from the fermentation of complex carbohydrates (agavins) and simple sugars. The biopolymer obtained by this rapid extraction protocol would be suitable for ecological and biomedical applications, due to the low melting temperature, less than 50% crystallinity, and the lack of lipopolysaccharides. Therefore, this extraction protocol might represent an alternative to the traditional protocol based on NaOCl-chloroform and is part of the green trend to improve the PHB production.

Lupeol, is naturally occurring compound present in plants, with some beneficial health effects. In the present study, organogel-based emulsions (o/w) were obtained from canola oil. Particle size analysis, rheology test, optical microscopy, and permeability of nutraceuticals by cell culture and UPLC-MS/MS were done. Particle hydrodynamic diameters obtained in organogel-based emulsions loaded with nutraceuticals were

Pumpkin pulp is the main waste generated by pumpkin seed growers. This agro-industrial waste is a valuable source of bioactive compounds, especially carotenoids (β-carotene, α-carotene, and lutein), which exhibit a broad spectrum of health-promoting effects. In this study, vegetable oils (canola, corn, and soybean oil) were used as green solvent alternatives to conventional organic solvents for carotenoid extraction from dried pumpkin pulp (DPP) waste. The highest carotenoid extraction yield (CEY) was obtained with canola oil, at a 1:10 DPP/oil ratio. Response surface methodology (RSM) was used to optimize the extraction process parameters (temperature, time, and stirring rate) through a Box-Behnken design (BBD) maximizing CEY in canola oil. The extraction temperature and stirring rate were found to have a significant linear and quadratic effect, respectively, on CEY. Optimum conditions were achieved at 21.8 min, 250 rpm, and 60°C. Under these optimized conditions, the estimated value for CEY was 378.1 µg β-carotene equivalents/g of DPP, corresponding to 61.6% of the total carotenoid content present in the DPP. In contrast, the observed experimental value was 373.2 µg β-carotene equivalents/g of DPP (61.2%). The experimental value was very close to the estimated value, which verifies the model's adequacy and fit. This study shows an alternative method to extract carotenoids from DPP with canola oil, obtaining an oil naturally enriched with carotenoids that could be used as a potential functional ingredient in the development of food, cosmetics, and medicinal products. PRACTICAL APPLICATION: Pumpkin by-products are a potential carotenoid source. Vegetable oil can be used as an alternative solvent for carotenoid extraction from pumpkin residues to obtain an enriched carotenoid oil that can be used to formulate food products.

The modification of vegetable oils from liquid to solid state gel type is achieved by organogelation, the first phenomenon experienced is nucleation that can be spectrophotometrically evaluated and obtain thermodynamic properties. The objective of the work was to evaluate the solid formation from nucleation to macroscopic properties of the mixture: sorbitan monopalmitate and ethyl cellulose in canola, olive and coconut vegetable oils. Nucleation kinetics, solid growth analysis, oscillatory rheology characterization, thermal properties by differential scanning calorimetry and microstructural formation by optical microscopy were evaluated. Non-isothermal nucleation kinetics indicated short induction times for canola and prolonged in coconut, the inclusion of ethyl cellulose involved a more compact solid formation in the systems, without modifying the growth parameters, the coconut organogel was more sensitive to thermal changes. Non-isothermal nucleation kinetics are useful for determining the thermodynamic properties of organogels and the closest to thermodynamic equilibrium, the inclusion of ethyl cellulose being decisive; same that does not influence formation speed and solid growth. The multicomponent gels obtained showed that the structural differences depend on the concentration of the mixture that includes ethyl cellulose, presenting more compact structures and thereby more resistant gels. Keywords: nucleation, organogelation, ethyl cellulose, vegetable oils.

Chemical modification of the native starch of Mexican Oxalis tuberosa was studied by cross-linking it with different concentrations of epichlorohydrin (0.5–2%). The results showed an extraction yield of 65.1 ± 0.20% (dry basis) for native starch, which can be considered as a potential unconventional source for starch extraction. The amylose contents of native and modified starch decreased from 24.66 to 13.57%, respectively. X-ray diffraction analysis showed an increase in the crystalline part in modified starch. The chemical modification changed the functional properties of starch. The clarity of the paste determined by spectrophotometer at 650 nm showed an inversely proportional relationship with the epichlorohydrin concentration. The lipid absorption index showed an increase up to 210% (using 2% epichlorohydrin) compared to that of native starch. The structure was analyzed by SEM and showed granules before and after the modification an ellipsoid morphology while the polarized light microscopy analysis showed birefringence patterns. The average diameter of the granules evaluated using a particle size analyzer (CILAS) ranged between 31.46 μm and 35.32 μm for modified starch and was 30.36 μm for the native starch, both higher than that of the corn-starch granules (16.10 μm). This makes the Mexican O. tuberosa an option for starch extraction and for application in the food industry.

The use of organogels in food and pharmaceutical sciences has several technical problems related with restricted diffusion of the drugs and lack of a proper gelator molecule. These features are important into the new product design. An alternative to improve technological properties in organogels is the use of emulsions. However, there is a lack of knowledge about the behavior on bioaccessibility and permeability of bioactives loaded into organogel-based emulsions. The objective of the present experimental work was to study the physical properties of organogel-based emulsions made with vegetable oil loaded with three different bioactives (betulin, curcumin and quercetin) and the influence on their bioaccessibility. Organogels were made of canola or coconut oils and myverol as gelator (10% w/w). Water-in-oil emulsions (at 5, 10 and 12.5 wt% of water content) were prepared by mixing the melted proper organogel and water (80 °C) under high shear conditions (20,000 rpm). Micrographs, rheological tests (amplitude, frequency, temperature sweeps and creep-compliance measurements), DSC and particle size analysis were performed to samples. In vitro digestion (oral, gastric and intestinal phase), lipolysis assays, bioaccessibility and permeability tests by cell culture of Caco-2 were made. Organogels of coconut oil have shown poor emulsification properties.

The objective of the present investigation was to evaluate the physical stability of emulsions (w/o) with a gel as an oil phase. Two oil phases (canola and coconut oil) were used to assess the impact of the different vegetable oils. Monoglycerides were used as the gelling agent and polyglycerol polyricinoleate as the surfactant. Micrographs, differential scanning calorimetry, and rheology tests were performed. The presence of crystalline structures was observed in the continuous phase characteristic of some organogels and a smaller distribution of sizes as a function of time. Also, a change in the crystallization profile of the aqueous and oily phases concerning to time was also found, the crystallization signals coinciding (≈ − 40 °C), indicating a better organization by the phases. No variability was found in modules G′ and G″, so these systems have good mechanical stability. The properties of the organogelated emulsions are explained by the interface-interface interactions present between the particles and the reduced mobility, which slows the phase separation.

Avocado seeds are an agroindustrial residue widely produced in Mexico that are causing various environmental problems due to their accumulation. The evaluation of avocado residues to recover biopolymers by microwave-assisted extraction (MAE) and the characterization of avocado starch properties were studied in the present work. A central-composite design was used to optimize the MAE process. Moreover, a comparison was performed between MAE non-isothermal mode (NO&ndash, ISO) and conventional extraction. Starch optimization by MAE was obtained at 161.09 &deg, C for 56.23 min with an extraction yield of 49.52% &plusmn, 0.69%, while with NO&ndash, ISO at 161 &deg, C was obtained 45.75% &plusmn, 2.18%. Conventional extraction was 39.04% &plusmn, 2.22%. Compared with conventional starch, MAE starch showed similar proprieties and molecular spectra. In contrast, MAE starch showed high solubility, low water absorption capacity, a non-granular structure with small particle size (&lt, 2 &micro, m) and polydispersity of fragments at different sizes of polymers. Therefore, MAE is a viable technology to extract the starch, and avocado seed can be considered an excellent starch source for the development of novel functional foods, contributing to promoting sustainability across the food chain.

Bioleaching is suggested as a methodology with benefits in ex situ/in situ bioremediation for reducing metal contamination in dredged sediments. The process of bioleaching assisted by microorganisms in a stirred tank is widely used, among other biohydrometallurgical techniques, for the efficient extraction of metals of interest if the recovery costs of valuable metals allow it. Measurement of the mass transfer capacity of oxygen in an aerobic bioreactor is of vital importance; this factor determines the productivity of the system, since it promotes microbial growth and hence enables a bioconversion process at the mineral surface takes place. The main objective of the present research was to determine the volumetric oxygen transfer coefficient (kLa) during the manganese bioleaching process in a stirred tank reactor using silicone oil as a vector to improve the transfer of gaseous substrates. Experiments were carried out in triplicate with a 22 factorial design analyzing temperature (30 and 40 °C) and stirring speed (300 and 500 rpm). The effect of viscosity on the system was also determined by modifying the concentrations of mining waste (30, 40, and 50%), ferrous sulfate (FeSO4 · 7H2O) (2, 4, 8, and 14%), and silicone oil (0, 5, and 10%) at 0 and 24 h of mixing. The results showed an increase in the value of kLawith respect to time, from kLa(0 h, 30 °C, 500 rpm) = 8.75 s−1 to kLa(24 h, 40 °C, 500 rpm) = 18.18 s−1; ANOVA statistical analysis was performed with the Fisher and Tukey tests and showed that there were statistically significant differences.

A rheological study was carried out to evaluate formulations of test dispersions and gels of high methoxyl pectins (HTHMP) obtained at different conditions from husk tomato waste (Physalis ixocarpa Brot.). The effect of extraction agent (hydrochloric acid or citric acid), blanching time (10 or 15min) and extraction time (15, 20 or 25min) on the rheology of the tested samples was evaluated. Flow behavior and activation energy were evaluated on the test dispersions, while (Ea) frequency sweeps, temperature sweep, creep-recovery test and penetration test were performed on the gels. HTHMP dispersions showed shear thinning flow behavior, while showing a good fit to Cross model. Extraction agent, blanching time and extraction time did not have effect on Cross parameters (ηz, η∞, C, and m). Ea decreased as blanching time and extraction time increased. Frequency sweeps revealed high dependence on frequency for both G' and G", while temperature sweeps (25- 95°C) showed thermostable husk tomato pectin gels. Hydrocloric acid (HCl) extracted pectin gels showed stronger structure than citric acid (CA) gels.

The Raman technique can be used in the monitoring of molecular changes in organogel emulsions by intensity changes and band shifts. Raman spectra were obtained from individual components, then from an organogel and then from organogel emulsions. Raman bands corresponding to chemical bonds involved in intermolecular interactions were followed up. Changes Raman in mixture of lipophilic components were observed with respect to individual components and subsequently upon inclusion of an aqueous phase in emulsified systems. The organogel emulsions showed variations in Raman bands of hydrogen bonding and hydrophobic interactions. Variations in intensity ratio values of some bonds indicate modifications in the packing of the continuous phase that is affected by slight changes in surfactant concentration in time.

Emulsions are thermodynamically unstable systems that, by incorporating more components in their formulation, increase their complexity and make their study challenging. However, a good selection of compounds in the formulation, and suitable methods for their preparation, could result in systems with favorable thermomechanical and microstructural properties for multiple applications. The objective of this research was to evaluate the influence of temperature, time, and surfactant concentration on the microstructural, thermodynamic, and rheological properties of organogel emulsions, and to present in a simple way the relationship between enthalpy of fusion and rheological properties (i.e., viscosity) in organogel emulsions W/O. Canola oil, monoglycerides and polyglyceryl polyricinoleate (PGPR) were used as the oil phase. Microscopy, DSC, and Creep-recovery tests were performed. A molecular organization phenomenon was observed that resulted in systems with a more dispersed and ordered microstructure, delaying the phase separation for 28 days of evaluation. In addition, an increase in the internal viscosity of the organogel emulsions was reflected in higher enthalpy of fusion values at 10 °C. An inverse behavior was also presented in emulsions at 25 °C. The combined activity of stabilizing agents, as well as the three-dimensional network formed in continuous phase, avoided phenomena of coalescence and phase separation by keeping distant the drops of water and the oily liquid phase, while leading to a better organized microstructure over time and retaining good rheological properties.

The aim of the present study was to investigate the gelling properties of Pinto Saltillo bean isolate protein (PSBIP) enriched with sodium alginate (SA). In solution, phase diagrams indicated cosolubility at different concentrations of the PSBIP-SA system that is homogeneous at low concentrations of PSBPI ( η 0 obtained using the Carreau model suggest stronger interactions between PSBPI (100 g/L) and SA (20 g/L) indicating the presence of a molecular network that cannot be significantly altered at low shear rates. In frequency studies, mixed gels formed through internal ionic gelation and temperature gradient denaturation, indicates that SA concentrations higher than 20 g/L increase the G′ and G″ values, improving the mechanical spectra in some cases of the binary gels; the K′, K″, n’, and n’’ values suggest that the modifications of the dynamic rheological properties of PSBPI-SA gels are synergistic. Viscoelastic analyses indicate that SA reduces the random associations of proteins in the mixed gels due to a more ordered network structure.

Pectin derived from pomace from the apple variety “Blanca de Asturias” was isolated by acidic extraction and characterized as an alternative source of pectin. The influence of solid:liquid ratio and the extraction time on the chemical, rheological and thermal properties were evaluated. The molecular weight (Mw) decreased from 865 kDa to 590 kDa due to the hydrolysis reaction, effect that is favored at higher extraction times and to the increment in the solid:liquid ratio. Rheological studies suggest that the chains of apple pomace pectin (APP) disentangled during a short period of oscillation at high frequency and were related to inter- and intra-interaction at the junction zones. The composition and rheological characteristics of APP from the variety “Blanca de Asturias” exhibited strong potential as a thickener and gelling agent in the food industry.

In this study the effect of agavin and inulin addition on the microstructural, textural, thermal and sensory properties of apple leathers was investigated. Agavins and inulin were added to leathers at two concentration levels (6 and 4%) individually and as a mixture. Scanning Electron Microscopy (SEM) revealed more compact and less porous matrices in the 6% concentration with respect to the control, influencing leather texture. In formulations with agavins the texture was significantly (p 0.05) smoother than in those with inulin. No relationship was found between hardness and glass transition temperature (Tg), but there was a significant difference between treated leathers and the control. The acceptability of the product showed a direct relationship with the hardness. There were significant changes in the leathers after storage. Agavins and inulin exhibited different technological properties and considering the texturising effect of the agavins, their potential for use in the food industry is promising.

Sodium alginate (SA) at 2% (w/v) and low acylated gellan gum (LAG) at 0.2% (w/v) were used to microencapsulate Lactobacillus helveticus and Lactobacillus delbrueckii spp lactis by employing the internal ionic gelation technique through water–oil emulsions at three different stirring rates: 480, 800 and 1200 rpm. The flow behavior of the biopolymer dispersions, the activation energy of the emulsion, the microencapsulation efficiency, the size distribution, the microcapsules morphology and the effect of the stirring rate on the culture viability were analyzed. All of the dispersions exhibited a non-Newtonian shear-thinning flow behavior because the apparent viscosity decreased in value when the shear rate was increased. The activation energy was calculated using the Arrhenius-like equation; the value obtained for the emulsion was 32.59 kJ/mol. It was observed that at 400 rpm, the microencapsulation efficiency was 92.83%, whereas at 800 and 1200 rpm, the stirring rates reduced the efficiency to 15.83% and 4.56%, respectively, evidencing the sensitivity of the microorganisms to the shear rate (13.36 and 20.05 s−1). Both optical and scanning electron microscopy (SEM) showed spherical microcapsules with irregular topography due to the presence of holes on its surface. The obtained size distribution range was modified when the stirring rate was increased. At 400 rpm, bimodal behavior was observed in the range of 20–420 μm; at 800 and 1200 rpm, the behavior became unimodal and the range was from 20 to 200 μm and 20 to 160 μm, respectively.