Cassava Residue Research Articles

A green extraction technology of lignocellulose from cassava residue by mechanical activation-assisted ternary deep eutectic solvent

Lignocellulose (LC) is a natural polymer material that holds immense potential for various applications. However, extracting LC from biomass wastes with high-starch content has been challenging due to low selectivity and yield. In this study, LC was prepared from cassava residue (CR) via a combination of mechanical activation pretreatment and a citric acid (CA)-enhanced ternary deep eutectic solvent (TDES) consisting of choline chloride (ChCl), lactic acid (LA), and CA. The mechanical activation reduces the size of CR, greatly promoting the removal ability for starch, lignin and hemicellulose using TDES, and thus improving yield and selectivity of LC through this method. The CA esterified LC to prevent its excessive hydrolysis and increased a significantly higher LC content (82.52 wt%) compared to mechanical activation only and DES without CA, increasing by 6.97 times and 1.26 times, respectively. The extraction temperature significantly affected the structure, composition, thermal stability of LC and the properties of recovered TDES. The LC extracted at 90 °C (LC-90) had the highest cellulose content (82.52 wt%), crystallinity index (44.82 %), and higher degradation temperature (339.7 °C). The properties of the recovered TDES and extraction mechanism were analyzed. This study provides a strategy for the high-value utilization of biomass waste.

Carbon Sequestration and Soil Fertility Management in Sandy and Clayey Soils Revealed by Over Four Decades of Long‐Term Field Experiments in Thailand

ABSTRACTWe investigated the impact of organic matter (OM) application on soil organic carbon (SOC) sequestration and cassava yield in sandy (sand content > 72% and > 62%) and clayey (sand content > 47%) soils through three long‐term experiments conducted from 1975 to 1976 in Thailand. Eight treatments—nitrogen (N), phosphorus (P), and potassium (K) fertilization, cassava residue (CR), and compost application (COM)—were assigned to the control (CT), N, NP, NK, NPK, CR, NPK + CR, and NPK + COM groups. Changes in SOC, cassava yield, and soil chemical properties, were recorded. Interactions of these parameters were visualized using structural equation modeling (SEM). SOC concentrations were determined at five different depths in 2021. A significant treatment effect was observed in the initial stage of the experiment in sandy soils. Conversely, in clayey soil, a significant effect was observed only in the later stage. SOC sequestration rates (mean ± SD of the three sites, Mg C ha−1 0.2 m−1) were in the order of NPK + COM (10.1 ± 6.5), NPK + CR (5.6 ± 3.1), CR (2.8 ± 2.0), NPK (2.0 ± 2.1), NK (1.9 ± 1.3), NP (1.8 ± 2.0), and N (1.2 ± 1.1). SEM highlighted the effect of OM application on SOC sequestration across the three sites. Furthermore, SOC increases positively influenced cassava yield in sandy but not in clayey soils. Vertical distribution of SOC showed consistent treatment effects in deeper soil layers, especially in sandy soils, underscoring the importance of considering deep soil layers for carbon sequestration.

Assessment of the chemical composition of buriti (Mauritia flexuosa Liliopsida) and cassava (Manihot esculenta Crantz) residues and their possible application in the bioproduction of coconut aroma (6 pentyl-α-pyrone).

This work aimed to define strategies to increase the bioproduction of 6 pentyl-α-pyrone (bioaroma). As first strategy, fermentations were carried out in the solid state, with agro-industrial residues: Mauritia flexuosa Liliopsida. and Manihot esculenta Crantz in isolation, conducting them with different nutrient solutions having Trichoderma harzianum as a fermenting fungus. Physicochemical characterizations, centesimal composition, lignocellulosic and mineral content and antimicrobial activity were required. Fermentations were conducted under different humidification conditions (water, nutrient solution without additives and nutrient solutions with glucose or sucrose) for 9days. Bioaroma was quantified by gas chromatography, assisted by solid-phase microextraction. The results showed the low production of this compound in fermentations conducted with sweet cassava (around 6ppm (w/w)). The low bioproduction with sweet cassava residues can probably be related to its starch-rich composition, homogeneous substrate, and low concentration of nutrients. Already using buriti, the absence of aroma production was detected. Probably the presence of silicon and high lignin content in buriti minimized the fungal activity, making it difficult to obtain the aroma of interest. Given the characteristics presented by the waste, a new strategy was chosen: mixing waste in a 1:1 ratio. This fermentation resulted in the production of 156.24ppm (w/w) of aroma using the nutrient solution added with glucose. This combination, therefore, promoted more favorable environment for the process, possibly due to the presence of fermentable sugars from sweet cassava and fatty acids from the buriti peel, thus proving the possibility of an increase of around 2500% in the bioproduction of coconut aroma.

Combined bioprocess for fermentative hydrogen production from food waste: A review

Bio hydrogen is a cheaper, sustainable and safer source to produce fuel comparable to energy obtained from fossil fuels. There are many experimental methods to produce bio hydrogen using food wastes as substrates that are acted upon by specific bacterial and fungal strains. Some of the methods include batch-dark fermentation, solid-state dark fermentation, dark-anaerobic hydrogen fermentation and integrated light-dark fermentation. Different food wastes are used in these fermentation processes such as kitchen food waste, potatoes peels, sugary waste water, fish, meats, grains, cassava residues, corn pulp and starchy solution etc. These food wastes are rich source of main raw materials that are required for bio hydrogen production such as cellulose, carbohydrates, fats, proteins, lipids, starch, phosphorus, volatile solids, Published experimental and research approaches revealed that the use of mixed dark-photo fermentative bacterial consortium in flat photo bioreactors and fermenters resulted in higher yield. Combined dark-photo fermentation is an advanced and promising strategy for increasing overall yield of bio hydrogen.

Biochar production from cassava waste biomass: A techno-economic development approach in the Colombian context

Biochar has been proposed as a potential bioproduct since applications have been elucidated in the agricultural and energy sectors. This research paper aims to (i) evaluate biochar production using cassava residues (i.e., branches and peels), (ii) elucidate potential biochar applications, and (iii) assess the economic potential of biochar production in Colombia. Biochar was produced through slow pyrolysis and characterized considering pH, conductivity, and thermal properties. The economic assessment was done by calculating profitability indicators. Higher biochar yields were obtained using cassava branches (0.11 tons/ton, wet basis). A slow pyrolysis plant with a processing scale higher than 3.4 tons/h, a feedstock cost of 148.7 USD/ton, and a biochar selling price of 1600 USD/ton is feasible in Colombia. Biochar is a business opportunity sine large quantity of waste is readily available in the cassava productive chain. Biochar has potential applications as biofuel, soil amendment, carbon capture agent, graphene-based material, and supercapacitor electrodes.

Utilization of Xylanase Enzymes Derived from Cassava in the Eco-Friendly Biobleaching of Pulp

<p align="center">The demand for paper has been increasing over time, leading to the pulp and paper industry becoming one of the largest contributors to global carbon emissions due to the chlorine-based bleaching process, particularly in Indonesia. An alternative to minimize chlorine usage involves using xylanase enzymes as part of the bleaching sequence. Xylanase can be produced from agricultural waste, including cassava residue, which contains a significant concentration of xylanase, approximately 21.3%. However, it still needs to be utilized in Indonesia. Therefore, this study aims to explore the production of xylanase enzymes from cassava residue and assess its effectiveness in the biobleaching process of pulp. The research methodology includes the production phase of xylanase enzymes by <em>Aspergillus niger</em>, chelating, bleaching sequence, bleaching, kappa number, and chemical saving assay. In the production of xylanase, the study determined that xylanase exhibits optimal activity under specific conditions, notably at a pH of 6 and a temperature of 60°C. Under these parameters, the enzymatic activity reached a level of 0.4986 U/mg protein. During the bleaching sequence, xylanase was used with doses of 0.3, 0.5, 0.7, 0.8, and 1 L/T pulp at 40, 45, 50, 55, 60, 65, and 70°C for 60 minutes. Following this process, bleaching was conducted at 65°C for 70 minutes, extraction at 80°C for 90 minutes, and a second bleaching phase. Subsequently, a kappa number test was performed, revealing the best kappa value at 60°C with a xylanase dose of 0.5 L/T pulp, reducing from an initial kappa number of 9 to 4.04. Additionally, under these conditions and dosage, xylanase enzymes could save approximately 23.67% in chlorine usage</p>

Cassava hydrolysates used as substrates for the production of second-generation ethanol by Saccharomyces cerevisiae ATCC 26602 immobilized in sodium alginate spheres

Cassava has a prominent position in the Brazilian agriculture and economy. During the production of flour, a very large volume of residue is generated. One way to use these residues is through the production of ethanol. In this context, the present research aimed to use cassava residues as raw material for ethanol production. For this, sulfuric acid was used at concentrations of 1.0 to 5.0% during 5, 10 and 15 minutes of heating in an autoclave. The fermentation was carried out by Saccharomyces cerevisiae ATCC 26602, and to achieve a better performance, it was immobilized in sodium alginate spheres. Ethanol production was also estimated using a synthetic medium added with glucose that served as a comparison standard. The results of the experiment showed that the highest concentration of reducing sugars obtained by the hydrolysis of the residue was with the use of 2.0% of H2SO4 with 15 min. heating at 121 ºC, releasing 56.26 g/L of reducing sugars. The parameters used that led to the highest production of ethanol by the yeast, 7.85 g/L of ethanol, were: pH of 6.5, growth temperature of 30 °C, without agitation. The results showed that cassava residues can be used as a potential substrate for ethanol production. Thus, this work presents data on the most suitable conditions for the use of these industrial wastes in order to generate less polluting fuel energy, an increasingly attractive feature in a world where economic and environmental concerns grow every day.

Mechanistic insights into Ga-modified hollow ZSM-5 catalyzed fast pyrolysis of cassava residue

The preparation of valuable chemicals by catalytic fast pyrolysis (CFP) is a promising and environmentally-friendly approach for the selective upgrading of waste cassava residue (CR). This work systematically investigated the conversion mechanism and kinetic characteristics of CR pyrolysis over Ga-modified hollow ZSM-5, for the purpose of enhancing aromatics production. The hollow configuration significantly regulated the structural characteristics of ZSM-5, thus facilitating the diffusion, deoxygenation, and aromatization of pyrolysis intermediates. The incorporation of Ga species and generated Brønsted acid sites remarkably accelerated the reaction rate and suppressed the carbonization at high temperatures, through enhancing the end scission of starch and cellulose components. With the aid of 5Ga/ZSM-H, the relative content of aromatics achieved 95.4% at 700 °C, and still maintained over 92.5% even after 5 cycles. The ring-opening and retro-aldol degradation were identified as crucial steps for the production of ketones and aldehydes separately, which were further transformed into hydrocarbon pools by deoxygenation and subsequently converted into aromatics via Diels-Alder reaction. Kinetic analysis demonstrated that the use of 5Ga/ZSM-H lowered the average activation energy of CR pyrolysis by 14.8%, particularly for the initial pyrolysis stage. Moreover, the plausible mechanism for aromatics formation from Ga-modified hollow ZSM-5 catalyzed CR pyrolysis was proposed.

High capacity and selective adsorption of Congo red by cellulose-based aerogel with mesoporous structure: Adsorption properties and statistical data simulation

Large quantities of organic dyes are discharged into the environment, causing serious damage to the ecosystem. Therefore, it is urgent to develop inexpensive adsorbents to remove organic dyes. A novel cellulose-based aerogel (MPPA) with 3D porous structure was prepared by using cassava residue (cellulose) as basic construction blocks, doping ferroferric oxide (Fe3O4) for magnetic separation, and applying polyethyleneimine (PEI) as functional material for highly efficient and selective capture of Congo red (CR). MPPA exhibited porous network structure, numerous active capture sites, nontoxicity, high hydrophilicity, and excellent thermal stability. MPPA showed superior adsorption property for CR, with an equilibrium adsorption capacity of 2018.14 mg/g, and still had an adsorption property of 1189.31 mg/g after five recycling procedures. In addition, MPPA has excellent selectivity for CR in four binary dye systems. The adsorption behavior of MPPA on CR was further explored using a multilayer adsorption model, EDR-IDR hybrid model and AOAS model. Electrostatic potential and independent gradient models were used to further verify the possible interaction between MPPA and CR molecules. In conclusion, MPPA is a promising adsorbent in the field of treating anionic dyes.

Evaluation of a bioenergy resource of agricultural residues and municipal solid wastes in Benin

<abstract> <p>Benin is one of the West African countries with low access to energy. Abundant residues are generated from different activities in Benin, most of which are not yet considered for energy generation. In this study, we aim to evaluate the potential of bioenergy resources from agricultural residues and municipal solid waste (MSW) in Benin. Eleven (11) agricultural residues have been considered in the study and four of them with high bioenergy potential have been used in the Bioenergy and Food Security Rapid Appraisal (BEFS RA) tool to evaluate how much electricity could be generated from gasification and analyze the social and economic benefits that can be attained. We also introduce the residue-to-product approach and the NPV and IRR method to estimate the potential of agricultural residues and MSW and analyze the viability of generating electricity through the gasification process. Data for agricultural residues have been collected from Benin's Directorate of Agricultural Statistics governmental website and MSW data is estimated using World Bank data for 2012 and 2025. Our estimation shows that a total bioenergy potential of 142.63 PJ can be generated from agricultural residue and MSW in Benin produced in 2021. Agricultural residues are the highest contributor, contributing up to 98%. The bioenergy potential available for electricity generation is estimated at 85.6 PJ with maize the major contributor at 45%, followed by cotton and cassava residues at 17% and 13%, respectively. The BEFS RA simulation shows that 20, 849; 83, 395 and 208, 488 kWh per year can be generated from the available feedstock based on using 10, 40, and 100 kW plants respectively. Moreover, the net present value and the internal rate of return of all power plants are positive, showing the importance of investing in power generation through gasification systems. It is also important that future bioenergy projects include maize, cotton, and cassava residue as a priority for bioenergy generation since their energy potential appears to be higher than for other crops.</p> </abstract>

Dry residue of cassava on slow-growing broiler diets, with or without the addition of carbohydrases.

Dry residue of cassava was studied on the digestibility, performance, intestinal measurements, with or without inclusion of carbohydrases, of slow-growing broilers. 160 Label Rouge broiler chickens, 21-d-old, were distributed in a randomized, 2x5 factorial arrangement (male and female x 0, 10, 20, 30 and 40% residue) (metabolism trial). 1,100 male chicks were distributed in a 2x5 factorial arrangement (with/without carbohydrases x 0; 2.5; 5.0; 7.5; and 10.0% residue), with five replicates (performance trial). Increasing residue levels led to increases in energetic values. Feed intake from 1-21-d-old and 1-63-d-old decreased linearly. At 42 d-old, feed intake and weight gain levels exhibited a quadratic response, which predicted a highest value at 3.32% and 4.77%, respectively, for diets without carbohydrases. For 21- and 42-d-old chickens, the inclusion of carbohydrases reduced the weight and length of the small intestine. The energetic values of the diets were positively influenced by the residue and had similar digestibility values for both sexes. Inclusion of up to 10% of residue in slow-growing broiler diets does not impaired performance and intestinal morphology. The addition of carbohydrases reduced the viscosity of the digesta but it was not enough to improve the performance of the birds.

Selective production of aromatics from catalytic fast pyrolysis of cassava residues over vanadium modified ZSM-5: Experimental and kinetic study

In the present study, vanadium modified ZSM-5 catalysts (denoted as xV/ZSM-5) were applied for the fast pyrolysis of cassava residues. Systematical structural characterizations were carried out to reveal the basic characteristics of as-prepared xV/ZSM-5. Remarkably, the incorporation of vanadium species endowed the catalysts with large amounts of Brønsted and Lewis acid sites, thus facilitating the formation of aromatics via catalytic cleavage, dehydration, decarbonylation, decarboxylation, cyclization, and aromatization. Among the as-prepared xV/ZSM-5, 3V/ZSM-5 was found to be much more efficient in the fast pyrolysis of cassava residues into aromatics. The total yield of aromatics was up to 22.63 wt% at 750 ℃ with a heating rate of 10 ℃/ms, and the corresponding apparent activation energy of 211.9 kJ/mol was attained. The recycling experiments demonstrated that the vanadium modified ZSM-5 catalysts presented good thermal stability and could be reused for several cycles. Furthermore, plausible reaction mechanism for the fast pyrolysis of cassava residues over vanadium modified ZSM-5 was discussed in depth.

New and effective cassava bagasse-modified biochar to adsorb Food Red 17 and Acid Blue 9 dyes in a binary mixture.

A promissory technic for reducing environmental contaminants is the production of biochar from waste reuse and its application for water treatment. This study developed biochar (CWb) and NH4Cl-modified biochar (MCWb) using cassava residues as precursors. CWb and MCWb were characterized and evaluated in removing dyes (Acid Blue 9 and Food Red 17) in a binary system. The adsorbent demonstrated high adsorption capacity at all pH levels studied, showing its versatility regarding this process parameter. The equilibrium of all adsorption experiments was reached in 30 min. The adsorption process conformed to pseudo-first-order kinetics and extended Langmuir isotherm model. The thermodynamic adsorption experiments demonstrated that the adsorption process is physisorption, exhibiting exothermic and spontaneous characteristics. MCWb exhibited highly efficient and selective adsorption behavior towards the anionic dyes, indicating maximum adsorption capacity of 131 and 150 mg g-1 for Food Red 17 and Acid Blue 9, respectively. Besides, MCWb could be reused nine times, maintaining its original adsorption capacity. This study demonstrated an excellent adsorption capability of biochars in removing dyes. In addition, it indicated the recycling of wastes as a precursor of bio composts, a strategy for utilization in water treatment with binary systems. It showed the feasibility of the reuse capacity that indicated that the adsorbent may have many potential applications.

PSII-18 Chemical Composition of Cassava-Based Feed Ingredients from South-East Asia

Abstract Diet formulation in animal production has traditionally relied on a limited number of feed ingredients. Cassava is a starchy tuber crop grown in tropical and subtropical areas that can be used as an alternative ingredient in animal diets due to increasing cereal grain prices and their impact on feed costs. Therefore, information about the chemical composition of cassava-based feed ingredients is needed to formulate diets. The objective of this study was to determine the chemical composition of cassava-based feed ingredients and test the hypothesis that there is variation in chemical composition among cassava products originating from different South-East Asian countries. Sources of dried peeled cassava roots, unpeeled cassava roots, cassava chips, cassava meal, high ash cassava meal, and cassava residue were used. All ingredients were analyzed for dry matter, gross energy, N, amino acids (AA), acid hydrolyzed ether extract, ash, minerals, starch, insoluble dietary fiber, soluble dietary fiber, and total dietary fiber. Peeled cassava roots, unpeeled cassava roots, cassava chips, and cassava meal were also analyzed for sugars. Data were analyzed by ANOVA to test statistical differences among all cassava-based ingredients, and an alpha value of 0.05 was used to assess significance among means. Results indicated that high ash cassava meal had greater (P < 0.05) dry matter and ash, but less (P < 0.05) starch and gross energy than all other cassava products (Table 1). Peeled cassava roots, unpeeled cassava roots, and cassava chips had greater (P < 0.05) starch than the other cassava ingredients. Cassava residue had greater (P < 0.05) Lys, insoluble, soluble, and total dietary fiber concentrations compared with the other cassava products, but Trp and Glu were greater (P < 0.05) in peeled cassava roots, cassava chips, and cassava meal samples compared with the other ingredients. The concentration of most minerals was greater (P < 0.05) in high ash cassava meal than in the other cassava products. In conclusion, cassava-based ingredients sold as peeled roots, unpeeled roots, chips, or meal have chemical compositions that are not different, and peeling seems to have little impact on chemical composition. High ash cassava meal has less nutritional quality compared with other cassava products due to low starch and gross energy. The high fiber content in cassava residue makes this ingredient more suitable for ruminants and sows than for younger pigs or poultry.

Eco-saving and green anode materials for Li-ion batteries utilizing oxide-decorated biocarbon substrates proceeded from cassava residues

In this work, an eco-saving and green anode structure (CRC) of MnO/Mn3O4 nanoparticles (NPs) anchored on biocarbon substrates derived from cassava residues (CRs) was designed and fabricated successfully by an in-situ method from MnCl2 and CRs. The amount of MnO/Mn3O4 NPs in the CRC can be effectively modulated by altering the mass ratio of MnCl2 to CRs. In Li-ion batteries, CRC anodes exhibit outstanding electrochemical performances such as high Coulombic efficiency, high capacity, excellent rate capacity, and stable cycling. The high reversible capacity of 698 mAh g−1 at 100 mA g−1 can be achieved even after 100 cycles. This could be accredited to the special structure of MnO/Mn3O4 NPs and biocarbon substrates. First, CR-derived biocarbon favors the alleviation of volume change and prevents the aggregation of MnO/Mn3O4 NPs during cycling. Then, an appropriate amount of MnO/Mn3O4 NPs formed on the surface and empty cages of biocarbon generate various free contacting channels between the electrolyte and active materials. Finally, MnO/Mn3O4 NPs intensify the electrochemical activity of biocarbon, leading to an increase in Li-storage capacities. Therefore, the facile in-situ method in this work is quite promising to produce cost-effective and eco-friendly anodes for Li-ion batteries utilizing recycled CRs and simple chemicals.

Evaluation of the effect of tween-80 and its additive amount on the maturity of cassava residue compost

Cellulose, hemicellulose, and lignin interweave to form a dense network structure that makes lignocellulosic biomass difficult to degrade. Tween-80 is a non-ionic surfactant that can be used to promote microbial growth and increase the rate of microbial metabolism in compost. In this study, different doses of Tween-80 were presented as additives in the composting process to reduce the composting time and improve the maturity of the compost. The composting trial was conducted in a 10 L reactor for 46 days. The results showed that the addition of the chemical surfactant Tween-80 increased the temperature in the composting process and could effectively promote the degradation of lignocellulose and reduce phytotoxicity. During the composting process, the microbial population showed exponential growth followed by a gradual decline. At the end of composting, Tween-80 added at 0.35% reduced the C/N ratio to 9.61, much lower than that of the CK group at 12.3. Meanwhile, the degradation rates of cellulose and hemicellulose increased by 2.76% and 7.86%, respectively. Toxicity experiments on compost products also proved that the seed germination index of compost with 0.35% Tween-80 addition increased to 98.57%, which is 17.33% higher than that without the addition. FT-IR and TG experiments showed that the addition of Tween-80 could effectively accelerate the composting process and promote the rapid maturation of the heap. In conclusion, the addition of 0.35% Tween-80 was most conducive to promoting the rapid decomposition of organic matter in cassava residue compost and improving the maturity of the heap.

A Review on Cassava Residues as Adsorbents for Removal of Organic and Inorganic Contaminants in Water and Wastewater

An increase in water demand for drinking, agriculture, and industries necessitates the treatment of water and wastewater. Among various conventional treatment techniques available, adsorption is found to be one of the most economical and feasible methods. Adsorbents from plant biomass are effective for the removal of organic and inorganic pollutants. Cassava has gained attention among researchers during the past decades due to its plentiful availability and resilient characteristics. Even though cassava contains cyanogenic glucosides as toxins, it is used in industries for development of various products. Cassava stem, rhizome, peel, and bagasse are industrial residues that are generated in abundance. The present review focusses on factors affecting adsorption using cassava residues, adsorbent preparation and activation methods, equilibrium, mass transfer, kinetics, and thermodynamic studies of adsorption.

Aromatics production from catalytic pyrolysis of waste cassava residue using La and P modified ZSM-5: Experimental and kinetic study

In the present study, selective transformation of waste cassava residues into aromatics via catalytic pyrolysis over as-prepared La and P modified ZSM-5 was systematically investigated, especially in the aspects of product regulation and kinetic analysis. Comprehensive physicochemical characterizations were undertaken for unveiling the essential structural properties of La and P modified ZSM-5. The introduction of La and P species significantly enriched the Lewis and Brønsted acid sites in ZSM-5, thus facilitating the directional pyrolysis of waste cassava residues into aromatics. Higher apparent activation energy for aromatics formation from waste cassava residues pyrolysis in the presence of La and P modified ZSM-5 might be due to the fact that the catalytic pyrolysis belonged to diffusion-controlled gas-solid reaction. In comparison with that of the parent ZSM-5, LaP2/ZSM exhibited better performance towards aromatics formation in waste cassava residues pyrolysis, wherein the relative content of aromatics reached 83.3% at a temperature of 650 °C. Gratifyingly, the relative content of aromatics was increased to 90.5% for the catalytic pyrolysis of acid pretreated cassava residue, in the case of LaP1/ZSM catalyst.

Carcass characteristics and meat quality of lambs fed diets with different roughage: concentrate ratios supplemented with liquid residue of cassava

The objective of this study was to evaluate the effects of lambs fed two roughage: concentrate (R:C) ratios, with or without the liquid residue of cassava (LRC) on carcass traits and meat quantity. Forty lambs (19.5 ± 1.45 kg body weight), non-castrated, crossbred Santa Inês were distributed in a completely randomized 2 × 2 factorial design. There was no effect (p > 0.05) of the inclusion of LRC on the variables. The roughage:concentrate ratio of 40:60 promoted higher values for empty body weight, hot carcass weight, cold carcass weight, subcutaneous thickness fat, cooling loss, Longissimus muscle area, carcass morphometric measurements, and commercial cuts. Higher weight of leg, muscles, fat, bone and other tissues, as well as for the ratio muscle:fat, and muscle:bone was observed in lambs fed 40R:60C. For the meat chemical composition, there was the effect (p < 0.05) only for ether extract (EE) for lambs fed 40R:60C ratio. The redness (a*) of meat was greater (p < 0.05) for lambs fed 80R:20C. The other physicochemical characteristics were not influenced. The roughage:concentrate ratio of 40:60 improves the carcass traits and commercial cuts, but does not promote changes in meat quality, independent of supplementation with liquid residue of cassava.

Chemical composition of cassava-based feed ingredients from South-East Asia.

Information about the chemical composition of cassava-based feed ingredients is needed to accurately formulate animal diets. A study was conducted to determine the chemical composition of cassava-based feed ingredients and to test the hypothesis that there is variation in chemical composition among cassava products originating from different South-East Asian countries. Sources of dried peeled and unpeeled cassava roots, cassava chips, cassava meal, high-ash cassava meal, and cassava residue were used. All samples were analyzed for dry matter, gross energy, nitrogen, amino acids (AA), acid-hydrolyzed ether extract (AEE), ash, minerals, total starch, insoluble dietary fiber, and soluble dietary fiber. Samples of peeled and unpeeled cassava roots, cassava chips, and cassava meal were also analyzed for sugars. High-ash cassava meal had greater (p<0.05) dry matter and ash, but lower (p<0.05) total starch and gross energy than all other cassava products. Peeled cassava roots, unpeeled cassava roots, and cassava chips had greater (p<0.05) total starch than the other cassava-based ingredients. Cassava residue had greater (p<0.05) concentrations of lysine, insoluble dietary fiber, and soluble dietary fiber compared with the other cassava products, but tryptophan and glutamic acid were greater (p<0.05) in peeled cassava roots, cassava chips, and cassava meal samples compared with the other ingredients. Concentration of most minerals was greater (p<0.05) in high-ash cassava meal than in the other cassava products. Cassava-based ingredients sold as peeled roots, unpeeled roots, chips, or meal have chemical compositions that are not different from each other, and peeling has little impact on chemical composition. High-ash cassava meal has lower nutritional quality compared with other cassava products due to low starch and gross energy. The high fiber content in cassava residue makes this ingredient more suitable for ruminants and sows than for younger pigs or poultry.