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1.
Heliyon ; 10(15): e34781, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39161841

RESUMO

Gasification is a thermochemical process that has gained significant interest in the field of biomass energy conversion. Despite the level of technological maturity of the process, the dynamic variation of the process as a result of changes in both the properties of the gasifying agent and biomass has not been analysed in sufficient depth. Therefore, the present study characterizes the process dynamically as a function of step-type changes in rice husk biomass moisture content and gasifying airflow. To identify stability conditions and the range for inducing disturbances, steady-state tests were carried out using a 32-factorial design. The experimental results demonstrate that within the tested range of airflow, the gasification process operates in the oxygen-limited zone. Despite increasing the airflow from 20 to 40 standard liters per minute (SLPM) and driving the reaction towards the combustion zone, the high temperatures achieved resulted in the gas reaching a peak Lower Heating Value (LHV) of 2.6 MJ/Nm3 and a gas power of 2.6 kW, with a Cold Gas Efficiency (CGE) of 62%. In contrast, the effect of biomass moisture content was negligible due to the thermal inertia of the reactor and the natural variation of the process. Dynamic evaluation revealed that the oxidation temperature and gas concentration were the variables that took the longest to return to stability after air disturbances. It took approximately 1200 s for the hydrogen (H2) concentration to stabilize, while the gas power required about 300 s. No clear results were observed regarding the impact of the dynamic disturbance in moisture content, which varied between 12.3% w.t and 21.5% w.t.

2.
Polymers (Basel) ; 16(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-39000643

RESUMO

Natural fiber reinforcements have the potential to enhance mechanical properties, thereby improving performance and durability in various applications. In this study, we comprehensively evaluated the impact of environmental degradation over 120 days on reprocessed polypropylene (PP) reinforced with corn husk fiber (CHF) composites. The manufactured systems underwent rigorous analysis using various techniques, including Fourier transform infrared spectroscopy, thermogravimetric analysis, optical microscopy, scanning electron microscopy, and tensile testing. These analyses revealed that climatic conditions significantly influenced (p < 0.05) the mechanical properties of all systems. Photodegradation led to surface morphological changes and chemical structures. Regardless, adding CHF filler proved a key factor, as it allowed for less susceptibility to environmental degradation than the reprocessed matrix. These findings, therefore, provide robust evidence supporting the feasibility of using CHF composites for manufacturing agricultural containers.

3.
J Microbiol Methods ; 223: 106976, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38925440

RESUMO

Pellet production represents a critical step for several processes requiring fungal biomass, nevertheless, its optimization is seldom reported. The use of finely ground rice husk as a microcarrier and co-substrate permitted a marked increase (≈ 2.7×) in the productivity of fungal pellet production using Trametes versicolor compared to traditional production methods. The pellets show similar structure and smaller size compared to typical sole-mycelium pellets, as well as comparable laccase activity. The efficiency of the pellets for biodegradation was confirmed by the removal of the crystal violet dye, achieving significantly faster decolorization rates compared to the traditionally produced pellets. The use of these pellets during the continuous treatment of the dye in a stirred tank bioreactor resulted in 97% decolorization operating at a hydraulic residence time of 4.5 d.


Assuntos
Biodegradação Ambiental , Reatores Biológicos , Corantes , Oryza , Oryza/microbiologia , Corantes/metabolismo , Corantes/química , Reatores Biológicos/microbiologia , Lacase/metabolismo , Biomassa , Violeta Genciana/metabolismo , Violeta Genciana/química , Trametes/metabolismo , Trametes/enzimologia , Micélio/metabolismo , Polyporaceae/metabolismo
4.
Materials (Basel) ; 17(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38893853

RESUMO

The development of bio-insultation materials has attracted increasing attention in building energy-saving fields. In tropical and hot-humid climates, building envelope insulation is important for an energy efficient and comfortable indoor environment. In this study, several experiments were carried out on a bio-insulation material, which was prepared by using rice husk as a raw material. Square rice husk-based insultation panels were developed, considering the ASTM C-177 dimensions, to perform thermal conductivity coefficient tests. The thermal conductivity coefficient obtained was 0.073 W/(m K), which is in the range of conventional thermal insulators. In a second phase of this study, two experimental enclosures (chambers) were constructed, one with rice husk-based insulation panels and the second one without this insulation. The measures of the temperatures and thermal flows through the chambers were obtained with an electronic module based on the ARDUINO platform. This module consisted of three DS18B20 temperature sensors and four Peltier plates. Daily temperature and heat flux data were collected for the two chambers during the dry season in Panama, specifically between April and May. In the experimental chamber that did not have rice husk panel insulation on the roof, a flow of up to 28.18 W/m2 was observed, while in the chamber that did have rice husk panels, the presence of a flow toward the interior was rarely observed. The rice husk-based insulation panels showed comparable performance with conventional insulators, as a sustainable solution that takes advantage of a local resource to improve thermal comfort and the reduction of the environmental impact.

5.
Polymers (Basel) ; 16(11)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38891558

RESUMO

When the cocoa pod husk (CPH) is used and processed, two types of flour were obtained and can be differentiated by particle size, fine flour (FFCH), and coarse flour (CFCH) and can be used as a possible reinforcement for the development of bio-based composite materials. Each flour was obtained from chopping, drying by forced convection, milling by blades, and sieving using the 100 mesh/bottom according to the Tyler series. Their physicochemical, thermal, and structural characterization made it possible to identify the lower presence of lignin and higher proportions of cellulose and pectin in FFCH. Based on the properties identified in FFCH, it was included in the processing of thermoplastic starch (TPS) from the plantain pulp (Musa paradisiaca) and its respective bio-based composite material using plantain peel short fiber (PPSF) as a reinforcing agent using the following sequence of processing techniques: extrusion, internal mixing, and compression molding. The influence of FFCH contributed to the increase in ultimate tensile strength (7.59 MPa) and higher matrix-reinforcement interaction when obtaining the freshly processed composite material (day 0) when compared to the bio-based composite material with higher FCP content (30%) in the absence of FFCH. As for the disadvantages of FFCH, reduced thermal stability (323.57 to 300.47 °C) and losses in ultimate tensile strength (0.73 MPa) and modulus of elasticity (142.53 to 26.17 MPa) during storage progress were identified. In the case of TPS, the strengthening action of FFCH was not evident. Finally, the use of CFCH was not considered for the elaboration of the bio-based composite material because it reached a higher lignin content than FFCH, which was expected to decrease its affinity with the TPS matrix, resulting in lower mechanical properties in the material.

6.
Sci Rep ; 14(1): 10391, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710729

RESUMO

Colombia has great potential to produce clean energy through the use of residual biomass from the agricultural sector, such as residues obtained from the life cycle of rice production. This document presents a mixed approach methodology study to examine the combustion of rice husks as a possible energy alternative in the Tolima department of Colombia. First, the physicochemical characteristics of the rice husk were analyzed to characterize the raw material. Next, System Advisor Model (SAM) software was used to model a bioenergy plant to obtain biochar, bio-oil, and biogas from the combustion of rice husks and generate performance matrices, such as thermal efficiency, heat rate, and capacity factor. Then, the project was evaluated for financial feasibility using a mathematical model of net present value (NPV) with a planning horizon of 5 years. Finally, a subset of the local population was surveyed to assess perspectives on the project in the region. The results of the rice husk physicochemical analysis were the following: nitrogen content (0.74%), organic carbon (38.04%), silica (18.39%), humidity determination (7.68%), ash (19.4%), presence of carbonates (< 0.01%), and pH (6.41). These properties are adequate for the combustion process. The SAM simulation showed that the heat transferred in the boiler was 3180 kW, maintaining an efficiency between 50 and 52% throughout the 12 months of the year, meaning that the rice husk can generate electricity and thermal energy. The financial analysis showed that the internal rate of return (IRR) was 6% higher than the opportunity interest rate (OIR), demonstrating economic feasibility of the project. The design and creation of a rice husk processing plant is socially and environmentally viable and has the potential to contribute to the economic development of the Tolima community and reduce greenhouse gases. Likewise, this activity has the potential to promote energy security for consumers and environmental sustainability while at the same time being economically competitive.


Assuntos
Oryza , Oryza/química , Colômbia , Biocombustíveis/análise , Biomassa , Agricultura/métodos , Carvão Vegetal/química
7.
Heliyon ; 10(7): e28402, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596090

RESUMO

Purpose of this study is to explore the extraction of potentially valuable cosmetic ingredients from rice crop residues, aiming to mitigate their environmental impact. Methods: We employed AOAC methods to analyze the fat, protein, ash, fiber, soluble, and insoluble carbohydrate content in these residues. To identify sugars rich in galactose and acidic sugars, a total soluble carbohydrate extraction was performed. Cellulose, as part of the insoluble carbohydrates, was isolated through alkaline and acid hydrolysis, while sodium silicate was derived from the ash. Characterization of insoluble cellulose and silicate involved techniques like FTIR, DSC, PXRD, microphotography, porosity assessments, and water absorption studies. For proteins, alkaline solubilization and precipitation at the isoelectric point were utilized, with quantification via BCA and amino acid profiling through gas chromatography. Evaluation of radical scavenging capacity using DPPH led to the calculation of apparent molecular weight via SDS-PAGE. Results: The results revealed low levels of gum, mucilage, and pectin in both residues, contrasting with a high concentration of insoluble polysaccharides. Among these, Iß cellulose displayed potential attributes for cosmetic applications due to its oil and water adsorption characteristics. However, silicates obtained from the ashes did not exhibit direct use potential. In terms of protein extraction, we observed antioxidant properties, with enhanced performance through enzymatic hydrolysis, achieving a hydrolysis degree of 30.41% and a DPPH radical absorption rate exceeding 70%. Conclusion: Rice residues, particularly husk and straw, shown valuable substances suitable for potential cosmetic applications, encompassing cellulose, hydrolyzed proteins, and ash as a silicate precursor.

8.
Polymers (Basel) ; 16(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38611155

RESUMO

In the current contribution, bacterial nanocellulose obtained from a by-product of Kombucha tea production and vegetal nanocellulose isolated from milled rice husks were employed as fillers of PLA-based composites prepared by intensive mixing followed by compression molding. Given the challenges associated with the incorporation of nanocelluloses-initially obtained as aqueous suspensions-into melt compounding processes, and also with achieving a proper dispersion of the hydrophilic nanofillers within PLA, three different nanofibrils incorporation strategies were studied: i.e., direct mixing of dried milled nanocelluloses and PLA; masterbatching by solvent casting of native nanocelluloses followed by melt compounding; and masterbatching by solvent casting of acetylated nanocelluloses followed by melt compounding. Composites with varying filler content (from 0.5 wt.% to 7 wt.%) were characterized in terms of morphology, optical properties, and mechanical performance. Results revealed the relative suitability of each strategy employed to promote nanocelluloses dispersion within the PLA matrix. PLA/nanocellulose masterbatches prepared by solvent casting proved to be particularly useful for feeding the nanocelluloses into the processing equipment in a dry state with limited hornification. Acetylation also contributed to a better dispersion of both nanocelluloses within the PLA matrix, although no clear positive impact on the mechanical properties of the films was observed. Finally, filler loading played an important role in the films' properties by increasing their stiffness while reducing their translucency.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38319422

RESUMO

Lignocellulosic biomass conversion applying thermochemical routes has been postulated as an alternative for generating renewable energy. This research compares energy-driven biorefineries based on two thermochemical routes addressed to upgrade rice husk and rice straw produced in the Department of Sucre-Colombia. Initially, this research analyzes the physico-chemical and structural characterization of the rice residues. Four different scenarios were proposed to compare the energy-driven biorefineries based on fast pyrolysis and gasification considering technical, economic, and environmental metrics. These biorefineries were simulated using the Aspen Plus V.14.0 software. The novelty of this research is focused on the identification of the biorefinery with the best techno-economic, energetic, and environmental performance in the Colombian context. Economic and environmental analyses were done by using economic metrics and emissions. From an economic perspective, the stand-alone gasification process did not have a positive economic margin. In contrast, the fast pyrolysis process has the best economic performance since this process has a positive profit margin. Indeed, scenario 1 (fast pyrolysis of both rice residues) presented an economic margin of 13.75% and emissions of 2170.92 kgCO2eq/kg for 10 years. However, this scenario was not energetically the best, holding second place due to the feedstock requirements, compared to gasification. The biorefinery scenario 1 has the best performance.

10.
Polymers (Basel) ; 16(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38257043

RESUMO

Additive manufacturing has garnered significant attention as a versatile method for fabricating green and complex composite materials. This study delves into the fabrication of polymer composites by employing polylactic acid (PLA) in conjunction with rice husk as a reinforcing filler. The filaments were made by an extruded filament maker and then were used to make tensile and impact samples by another extrusion technology, fused deposition modeling (FDM). The structural and morphological characteristics of the composite materials were analyzed using scanning electron microscopy SEM. Results show that both the filament and samples are very reliable in producing polymer parts with this rice husk solid waste. This research contributes to increasing materials' circularity and potentially creating a local social economy around rice production, where this waste is not much used.

11.
Polymers (Basel) ; 16(2)2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38276697

RESUMO

The present work evaluates the influence of different properties of composite materials from natural sources. Films were prepared using the evaporative casting technique from corn starch reinforced with a waste material such as garlic husk (GH), using glycerin as a plasticizer. The results of the syntheses carried out demonstrated the synergy between these materials. In the morphological analysis, the compatibility and adequate dispersion of the reinforcer in the matrix were confirmed. Using Fourier transform infrared spectroscopy (FTIR), the interaction and formation of bonds between the matrix and the reinforcer were confirmed by the presence of some signals such as S-S and C-S. Similarly, thermogravimetric analysis (TGA) revealed that even at low concentrations, GH can slightly increase the decomposition temperature. Finally, from the results of dynamic mechanical analysis (DMA), it was possible to identify that the storage modulus increases significantly, up to 115%, compared to pure starch, especially at low concentrations of the reinforcer.

12.
Biotechnol Lett ; 46(1): 85-95, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38064041

RESUMO

The objective of this study was to obtain sufficient information on the thermal stabilization of a food-grade lipase from Thermomyces lanuginosus (TLL) using the immobilization technique. To do this, a new non-porous support was prepared via the sequential extraction of SiO2 from rice husks, followed by functionalization with (3-aminopropyl) triethoxysilane - 3-APTES (Amino-SiO2), and activation with glutaraldehyde - GA (GA-Amino-SiO2). We evaluated the influence of GA concentration, which varied from 0.25% v v-1 to 4% v v-1, on the immobilization parameters and enzyme thermal stabilization. The thermal inactivation parameters for both biocatalyst forms (soluble or immobilized TLL) were calculated by fitting a non-first-order enzyme inactivation kinetic model to the experimental data. According to the results, TLL was fully immobilized on the external support surface activated with different GA concentrations using an initial protein load of 5 mg g-1. A sharp decrease of hydrolytic activity was observed from 216.6 ± 12.4 U g-1 to 28.6 ± 0.9 U g-1 of after increasing the GA concentration from 0.25% v v-1 to 4.0% v v-1. The support that was prepared using a GA concentration at 0.5% v v-1 provided the highest stabilization of TLL - 31.6-times more stable than its soluble form at 60 °C. The estimations of the thermodynamic parameters, e.g., inactivation energy (Ed), enthalpy (ΔH#), entropy (ΔS#), and the Gibbs energy (ΔG#) values, confirmed the enzyme stabilization on the external support surface at temperatures ranging from 50 to 65 °C. These results show promising applications for this new heterogeneous biocatalyst in industrial processes given the high catalytic activity and thermal stability.


Assuntos
Lipase , Oryza , Propilaminas , Silanos , Lipase/metabolismo , Dióxido de Silício , Glutaral , Enzimas Imobilizadas/metabolismo , Termodinâmica , Estabilidade Enzimática
13.
Int J Biol Macromol ; 254(Pt 2): 127805, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37918600

RESUMO

In this work, an over-the-counter commercial dye, containing direct blue 151 in its composition, which is also discarded without any environmental regulation, was efficiency photodegraded using a green chemistry-synthesized nanocomposites type silver nanoparticles (AgNPs) supported on pistachio husk (PH). The green synthesis (GS) of the nanocomposites was carried out using the Anemopsis californica leaf extract (ExAc) as a reducing-stabilizing agent (AgNPs/ExAc-PH), for the first time. The presence of AgNPs on the nanocomposite surface was corroborated by field emission transmission electron microscope (FE-TEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The synthesized AgNPs/ExAc-PH has a bimodal size of 24 and 25 nm (4.86 % each) and a 0.72 % of AgNPs on its surface. AgNPs were adhered to the PH surface, through secondary bonds between the Ag and the cellulose of the PH. The optimum conditions, for efficient photocatalytic degradation, were 5 mg of nanocomposite, 3.18 × 10-2 M of NaBH4, natural sunlight, and stirring; this results in a photodegradation efficiency of 100 % almost instantaneously. Furthermore, it was shown that the dye degradation process is primarily due to the photocatalytic degradation of the dye, which occurs almost instantaneously.


Assuntos
Nanopartículas Metálicas , Nanocompostos , Pistacia , Prata/química , Compostos Azo , Celulose , Nanopartículas Metálicas/química , Substâncias Redutoras , Nanocompostos/química , Extratos Vegetais/química , Antibacterianos/química
14.
Environ Sci Pollut Res Int ; 30(59): 123616-123632, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37991611

RESUMO

Pristine pyrogenic carbonaceous material (BRH) obtained from rice husk and modified with FeCl3 (BRH-FeCl3) were prepared and explored as carbocatalysts for the activation of peroxymonosulfate (PMS) to degrade a model pharmaceutical (acetaminophen, ACE) in water. The BRH-FeCl3/PMS system removed the pharmaceutical faster than the BRH/PMS. This is explained because in BRH-FeCl3, compared to BRH, the modification (iron played a role as a structuring agent mainly) increased the average pore diameter and the presence of functional groups such as -COO-, -Si-O-, or oxygen vacancies, which allowed to remove the pollutant through an adsorption process and significant carbocatalytic degradation. BRH-FeCl3 was reusable during four cycles and had a higher efficiency for activating PMS than another inorganic peroxide (peroxydisulfate, PDS). The effects of BRH-FeCl3 and PMS concentrations were evaluated and optimized through an experimental design, maximizing the ACE degradation. In the optimized system, a non-radical pathway (i.e., the action of singlet oxygen, from the interaction of PMS with defects and/or -COO-/-Si-O- moieties on the BRH-FeCl3) was found. The BRH-FeCl3/PMS system generated only one primary degradation product that was more susceptible to biodegradation and less active against living organisms than ACE. Also, the BRH-FeCl3/PMS system induced partial removals of chemical oxygen demand and dissolved organic carbon. Furthermore, the carbocatalytic system eliminated ACE in a wide pH range and in simulated urine, having a low-moderate electric energy consumption, indicating the feasibility of the carbocatalytic process to treat water polluted with pharmaceuticals.


Assuntos
Oryza , Água , Peróxidos/química , Preparações Farmacêuticas
15.
Artigo em Inglês | MEDLINE | ID: mdl-37884710

RESUMO

Grain cultivation and its impacts on the environment have been the focus of many studies, especially due to generated solid waste and the wide use of agrochemicals aiming for greater productivity. In this context, the present study proposes a new and consistent step in constructing self-sustainability in rice farming. The proposed stage includes reusing green silica waste as an adsorbent to treat effluents contaminated by pesticides directly applied to rice cultivation. After nano silica production through the rice husks burning, followed by basic leaching and acid precipitation, a carbonaceous material remains. This material, naturally impregnated by Na2SiO3, was washed and dried, characterized, and used to remove the pesticide 2,4-dichlorophenoxyacetic acid (2,4-D). The adsorption essays were performed at 2,4-D at low concentrations (between 1 and 10 mg L-1) at different temperatures. The washed and dried porous carbon (WDPC) surface is irregular and presents slit-shaped channels. The FT-IR analysis identified the siloxane, carbonyl, carboxylate, and methylene functional groups available to interact with the pesticide molecules. The washing/drying process eliminated impurities, improving the surface area from 539.67 to 619.67 cm2 g-1 and pore volume from 0.29 to 0.44 cm3 g-1. Concerning the adsorption of 2,4-D on WDPC, the best pH was 6.0, where around 75% of the pesticide was removed from the water. The equilibrium isotherms presented an S-shaped form indicating a multilayer and cooperative adsorption, with maximum adsorption capacities of 7.504 and 7.736 mg g-1. The estimated ∆Gads, ΔHads, and ΔSads values suggested that pesticide adsorption was spontaneous, exothermic, and favorable. Finally, WDPC demonstrated a good potential to uptake 2,4-D from water, contributing to self-sustainability in rice farming.

16.
Materials (Basel) ; 16(19)2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37834694

RESUMO

In this work, the Honduras Mahogany (Swietenia macropnylla King, SMK) seed husk was used as a novel biomass resource for producing activated carbon by physical activation. The texture characteristics and chemical characterization of resulting products were investigated in correlation with the process parameters. Based on the thermochemical properties of the SMK biomass, the process conditions were set to a rate of about 10 °C/min under nitrogen (N2) flow of 500 cm3/min heated to 500 °C, then switched to carbon dioxide (CO2) flow of 100 cm3/min in the specified activation conditions (i.e., temperature of 700-850 °C for holding times of 0-60 min). Our findings showed that the texture characteristics (i.e., surface area and pore volume) increased with an activation temperature increase from 700 to 800 °C for a holding time of 30 min but gradually decreased as the temperature increased thereafter. Similarly, the texture characteristics also indicated an increasing trend with the residence time extending from 0 min to 30 min but slightly decreased as the time was extended to 60 min. Therefore, the optimal activation conditions for producing SMK-based activated carbon should be set at 800 °C for a holding time of 30 min to obtain the maximal texture characteristics (i.e., BET surface area of 966 m2/g and total pore volume of 0.43 cm3/g). On the other hand, the chemical characteristics were analyzed by energy dispersive X-ray spectroscopy (EDS) and Fourier Transform infrared spectroscopy (FTIR), showing oxygen complexes contained on the hydrophilic surface of the resulting activated carbon.

17.
J Fungi (Basel) ; 9(10)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37888247

RESUMO

Lentinula edodes is known to show high nutritional and organoleptic properties and can be mixed with different by-products in the production of new foods with important functional characteristics. Cocoa pod husk (CPH) is the main by-product in the cocoa industry and presents important bioactivities. In this research, two mixtures were applied based on Lentinula edodes mushroom flour from fifty different strains (strain 1 to strain 50) and cocoa pod husk flour (CPHF): 60% Lentinula edodes mushroom flour from each strain mixed with 40% CPHF (Mixture 1), and 80% Lentinula edodes mushroom flour from each strain mixed with 20% CPHF (Mixture 2). The parameters evaluated were moisture, proteins, fat, total dietary fiber (TDF), ash, carbohydrates, antioxidant capacity, antimicrobial activity, pH and water activity (aw). The multivariate statistical techniques evaluated those samples that exhibited the highest degree of correlation with the distinct chemical and commercial parameters, showing that sample 13 of both mixture flours (M1 and M2) obtained by the mushrooms of L. edodes (strain 13) with CPH indicated the higher significant of the parameters. In addition, the sensory test of the best flour (sample 13) was applied to 50 panelists, presenting the best sensory characteristics, such as color, aroma, texture and general acceptability.

18.
Foods ; 12(14)2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37509803

RESUMO

Given the substantial world coffee production, tons of coffee fruit cascara rich in bioactive compounds are discarded annually. Using this by-product to produce potentially healthy and acceptable foods is a sustainable practice that aggregates value to coffee production and may help improve people's lives. This study aimed to elaborate kombuchas from coffee cascara tea, evaluate their microbial profile, and monitor the changes in the volatile profile during fermentation, together with sensory attributes and acceptance by consumers from Rio de Janeiro (n = 113). Arabica coffee cascaras from Brazil and Nicaragua were used to make infusions, to which black tea kombucha, a Symbiotic Culture of Bacteria and Yeasts (SCOBY), and sucrose were added. Fermentation of plain black tea kombucha was also monitored for comparison. The volatile profile was analyzed after 0, 3, 6, and 9 days of fermentation via headspace solid phase microextraction GC-MS. A total of 81 compounds were identified considering all beverages, 59 in coffee cascara kombuchas and 59 in the black tea kombucha, with 37 common compounds for both. An increase mainly in acids and esters occurred during fermentation. Despite the similarity to black tea kombucha, some aldehydes, esters, alcohols, and ketones in coffee cascara kombucha were not identified in black tea kombucha. Potential impact compounds in CC were linalool, decanal, nonanal, octanal, dodecanal, ethanol, 2-ethylhexanol, ethyl acetate, ethyl butyrate, ethyl acetate, ß-damascenone, γ-nonalactone, linalool oxide, phenylethyl alcohol, geranyl acetone, phenylacetaldehyde, isoamyl alcohol, acetic acid, octanoic acid, isovaleric acid, ethyl isobutyrate, ethyl hexanoate, and limonene. The mean acceptance scores for cascara kombuchas varied between 5.7 ± 0.53 and 7.4 ± 0.53 on a nine-point hedonic scale, with coffee cascara from three-day Nicaragua kombucha showing the highest score, associated with sweetness and berry, honey, woody, and herbal aromas and flavors. The present results indicate that coffee cascara is a promising by-product for elaboration of fermented beverages, exhibiting exotic and singular fingerprinting that can be explored for applications in the food industry.

19.
Molecules ; 28(13)2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37446659

RESUMO

The objective of the present study was to evaluate the effect of dietary fiber from soybean (glycine max) husk as fat and phosphate replacer on the nutritional, physicochemical, and nutraceutical quality of Frankfurter sausage. A traditional formulation was used for the pork-based sausage and three treatments were established: control treatment (CT), sausage without SHDF; treatment 1 (T1), sausage and 1% SHDF; treatment 2 (T2), sausage and 1.5% SHDF. T2 showed the best nutritional contribution of the treatments, significantly favoring a lower content of fat and sodium, thus increasing the contribution of dietary fiber and calcium. A positive effect of SHDF on the water-holding capacity of the treatments was also observed. In addition, T2 remained stable during storage, while T1 and CT showed significantly reduced water-holding capacities of approximately 5%; this was in turn linked to hardness, as it was observed that on day 7 of storage, 27% less force was required to deform the T2 sausages. Regarding color, no significant difference was observed with the addition of SHDF to the product. The results suggest that the dietary fiber extracted from soybean husks has potential for application in food and can be used as an ingredient to improve the functional and nutritional quality of Frankfurter sausages by reducing the content of fat and phosphates.


Assuntos
Glycine max , Fosfatos , Glycine max/química , Fosfatos/química , Suplementos Nutricionais , Fibras na Dieta , Água
20.
Heliyon ; 9(6): e17258, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37389052

RESUMO

Theobroma cacao L. species, cultivated worldwide for its valuable beans, generates up to 72% weight of the fruit as waste. The lack of reutilization technologies in the cocoa agroindustry has hindered the exploitation of valuable bio-components applicable to the generation of high value added bioproducts. One such bioproduct is microfibrillated cellulose (MFC), a biopolymer that stands out for its desirable mechanical properties and biocompatibility in biomedical, packing, 3D printing, and construction applications. In this study, we isolated microfibrillated cellulose (MFC) from cocoa pod husk (CPH) via oxalic acid hydrolysis combined with a steam explosion. MFC isolation started with the Solid/Liquid extraction via Soxhlet, followed by mild citric acid hydrolysis, diluted alkaline hydrolysis, and bleaching pre-treatments. A Response Surface Methodology (RSM) was used to optimize the hydrolysis reaction at levels between 110 and 125 °C, 30-90 min at 5-10% (w/v) oxalic acid concentration. The cellulose-rich fraction was characterized by Fourier-Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) analyses. Characterization analyses revealed a cellulose-rich polymer with fibers ranging from 6 to 10 µm, a maximum thermal degradation temperature of 350 °C, and a crystallinity index of 63.4% (peak height method) and 29.0% (amorphous subtraction method). The optimized hydrolysis conditions were 125 °C, 30 min, at 5% w/v oxalic acid: with a 75.7% yield. These results compare with MFC obtained through highly concentrated inorganic acid hydrolysis from different biomass sources. Thus, we show a reliable and greener alternative chemical treatment for the obtention of MFC.

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