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Biofortified cassava (Manihot esculenta) plays a crucial role in enhancing the nutritional value of this essential staple, particularly in regions with limited dietary diversity and prevalent nutritional deficiencies. The cassava program at the International Center of Tropical Agriculture has dedicated over a decade to increase β‐carotene content in biofortified cassava, simultaneously focusing on improving yield, dry matter, and plant architecture. This paper presents realized genetic gains in biofortified cassava by analyzing the data from replicated multilocation breeding yield trials at the target population of environments spanning a 10‐year period (2013–2022). Following data curation, we observed significant positive genetic gains per year for β‐carotene content (7.03%), fresh yield (4.15%), dry matter content (0.55%), and height at the first branch (1.29%). A negative correlation between β‐carotene content and dry matter content was observed within 78% of trials. Moreover, our study uncovered a significant negative correlation between β‐carotene content and fresh root yield (r = −0.22, p < 0.01) and an unfavorable positive correlation between β‐carotene content and the number of branches (r = 0.23, p < 0.01). Such negative correlations between β‐carotene content and farm‐preferred traits presented substantial challenges for the development of biofortified cassava varieties. This research showed significant genetic gains and navigated the complexities of biofortified cassava development, providing breeding insights to enhance nutritional value while optimizing agronomic performance. Core Ideas: The biofortified cassava population was simultaneously improved over a decade for quality and agronomic traits.Significant rates of genetic gains were achieved in β‐carotene content, yield, dry matter, and plant architecture.Negative correlations were observed between β‐carotene content and dry matter, as well as fresh root yield.The observed trade‐offs present substantial challenges in developing biofortified cassava cultivars. Plain Language Summary: Biofortification, the method of increasing nutrient levels in crops through selective breeding, can help alleviate global hidden hunger or micronutrient deficiencies. Researchers have biofortified cassava (Manihot esculenta), a food staple for millions in the tropics, by increasing the β‐carotene (provitamin A) content in roots. This involved years of careful selection and testing of cassava plants with high β‐carotene, high yield, and optimal plant characteristics. Researchers monitor this process by calculating what is known as genetic gain, an indicator of the change or improvement of cassava traits over time. Substantial genetic gains have been achieved in β‐carotene content, yield, and plant type over a decade. Yet, gains in nutritional quality (high β‐carotene content) sometimes come at the expense of sacrificing other desirable traits like high yield. Overcoming these trade‐offs is crucial for developing new cassava varieties that excel in all desirable traits. [ABSTRACT FROM AUTHOR]

Background: Cassava roots are widely consumed in tropical regions of Asia, Africa, and Latin America. Although the protein, vitamin, carotenoid, and mineral content in the leaves makes them a nutritionally attractive option, their consumption is limited due to their high levels of cyanogenic compounds (CCs). In this study, the CC content in different parts of the plant (leaves, storage root cortex, and parenchyma) was assessed at harvest for 50 landrace genotypes representative of cassava diversity in Latin America. The changes in CC in leaves at different physiological ages (3, 6, 9, and 11 months after planting) were also investigated. Results: The average CC was higher in the cortex (804 ppm) and leaves (655 ppm) than in root parenchyma (305 ppm). Genotypes from different regions of Latin America, as identified by seven genetic diversity groups, differed significantly in CC levels. The Andean and Amazon groups had, respectively, the lowest (P = 0.0008) and highest (P < 0.0001) CC levels in all three parts of the plants. Cyanogenic compound concentrations were higher in leaves from young plants (P < 0.0001) and decreased with increasing physiological age. Conclusion: The results help to guide the selection of parental lines with low CC levels for breeding and to contribute to the expanded use of cassava and its by‐products for food and feed. Cassava for fresh consumption, especially, requires varieties with low total CC content, especially in the root cortex and parenchyma. COL1108 (204, 213, and 174 ppm, respectively, in the parenchyma, cortex, and leaves) and PER297 (83, 238, and 299 ppm, respectively, in the parenchyma, cortex, and leaves) can fulfill this requirement. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: The purpose of this study was to investigate the potential of hyperspectral imaging for the characterization of cooking quality parameters, dry matter content (DMC), water absorption (WAB), and texture in cassava genotypes contrasting for their cooking quality. RESULTS: Hyperspectral images were acquired on cooked and fresh intact longitudinal and transversal slices from 31 cassava genotypes harvested in March 2022 in Colombia. Different chemometric methods were tested for the quantification of DMC, WAB, and texture parameters. Data analysis was conducted through partial least squares regression, K nearest neighbors regression, support vector machine regression and CovSel multiple linear regression (CovSel_MLR). Efficient performances were obtained for DMC using CovSel_MLR with, coefficient of multiple determination Rp2=0.94, root‐mean‐square error of prediction RMSEP = 0.96 g/100 g, and ratio of the standard deviation values RPD = 3.60. High heterogeneity was observed between contrasting genotypes. The predicted distribution of DMC within the root can be homogeneous or heterogeneous depending on the genotype. Weak predictions were obtained for WAB and texture parameters. CONCLUSIONS: This study showed that hyperspectral imaging could be used as a high‐throughput phenotyping tool for the visualization of DMC in contrasting cooking quality genotypes. Further improvement of protocols and larger datasets are required for WAB and texture quality traits. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Consumers of boiled cassava in Africa, Latin America and Asia use specific preference criteria to evaluate its cooking quality, in terms of texture, colour and taste. To improve adoption rates of improved cassava varieties intended for consumption after boiling, these preference criteria need to be determined, quantified and integrated as post‐harvest quality traits in the target product profile of boiled cassava, so that breeding programs may screen candidate varieties based on both agronomic traits and consumer preference traits. RESULTS: Surveys of various end‐user groups identified seven priority quality attributes of boiled cassava covering root preparation, visual aspect, taste and texture. Three populations of contrasted cassava genotypes, from good‐cooking to bad‐cooking, in three countries (Uganda, Benin, Colombia) were then characterized according to these quality attributes by sensory quantitative descriptive analysis (QDA) and by standard instrumental methods. Consumers' preferences of the texture attributes mealiness and hardness were also determined. By analysis of correlations, the consumers' preferences scores were translated into thresholds of acceptability in terms of QDA scores, then in terms of instrumental measurements (water absorption during boiling and texture analysis). The thresholds of acceptability were used to identify among the Colombian and Benin populations promising genotypes for boiled cassava quality. CONCLUSION: This work demonstrates the steps of determining priority quality attributes for boiled cassava and establishing their corresponding quantitative thresholds of acceptability. The information can then be included in boiled cassava target product profiles used by cassava breeders, for better selection and adoption rates of new varieties. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: The consumption of foods such as sweet potato and cassava with high levels of carotenoids is a possible solution to reduce vitamin A deficiency. In this study, we evaluated the kinetics of thermal degradation of carotenoids. The content of carotenoids was quantified by high‐performance liquid chromatography, first in fresh material, then in flour and finally in bakery products using mixtures of wheat, sweet potato and cassava. The degree of acceptance of the bakery products by children was also assessed through a sensory acceptance test. Results: The study found that the degradation of carotenoid compounds in sweet potato followed first‐order kinetics and fitted the Arrhenius equation with correlations of R2 > 0.9. The retention rates of all‐trans‐β‐carotene were 77%, 56% and 48% at cooking temperatures of 75, 85 and 95 °C respectively, during a cooking time of 20 min. The concentrations of all‐trans‐β‐carotene, after baking, for bread, cookies and cake were 15, 19 and 14 μg g−1 db, respectively. In a sensory acceptance test carried out in a school, 47.6% of the boys and 79.2% of the girls rated the cookies made from a mixture of cassava, sweet potato and wheat flour with the indicator I like it a lot. Conclusion: The content of carotenoid compounds was reduced by exposure to high temperatures and long cooking times. The combinations of cooking time and temperature which minimized degradation of all‐trans‐β‐carotene occurred at 75 °C–20 min and 95 °C–10 min. All‐trans‐β‐carotene retentions for bread, cookies and cake were 25%, 15% and 11% respectively. The mixture of wheat, sweet potato and cassava flour can be considered in the development of cookies with positive contributions of all‐trans‐β‐carotenes and with a good acceptance by children between 9 and 13 years old. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Attiéké, made from biofortified (yellow) cassava genotypes, requires a new cooking method to minimize carotenoid degradation during processing. Thus, this research is aimed at designing and building a more efficient steamer to produce high-quality attiéké from biofortified cassava roots. Using three improved biofortified cassava genotypes (IBA141092, IBA070593, and IBA011368) obtained from IITA research farms, attiéké samples were produced using traditional and developed steamers. The results show that the developed steamer outperformed the traditional steamer; it was 1.5 times faster, used less fuel (2.6 times less), and had higher true carotenoid retention. The developed steamer genotype IBA070593 had the highest true retention of 90.4 percent, while the traditional steamer genotype IBA0141092 had the lowest carotenoid retention of 61.9 percent and the highest in the developed steamer (62.4 percent). When compared to the traditional steamer, the developed steamer had better cooking performance and a more extraordinary ability to retain carotenoids. Thus, the developed steamer is recommended for attiéké processors due to its improved cooking performance, and using this steamer to produce attiéké from biofortified cassava will help to alleviate vitamin A deficiency among attiéké consumers. [ABSTRACT FROM AUTHOR]

BACKGROUND: The isosteric heat of desorption is vital in evaluating the energy performance of food dryers. The isosteric heat of desorption was investigated for different cassava (Manihot esculenta Crantz) products prepared as flour or starch, with and without fermentation. An automated moisture sorption gravimetric analyser was used to measure the desorption isotherms over 10–90% relative humidity of the drying air at temperatures ranging from 25 to 65 °C. RESULTS: Analysis of variance showed an imperceptible contribution of the preparation method in the measured desorption data. This finding also agreed with microscopical images, which revealed the lack of compelling structural differences among different products. A set of empirical sorption equations suggested by the ASAE standard was examined over the measured desorption isotherms. The standard error of estimation was found to be in the acceptable range of 2.36–3.71%. Furthermore, the fulfilment of the enthalpy‐entropy compensation theory was considered as an additional criterion in the thermodynamic results of different sorption equations, besides their fitting adequacy. The modified Chung–Pfost equation has proved to be the most suitable equation for cassava products, as it is capable of reflecting the temperature dependency of the isosteric heat of desorption. The net isosteric heat of desorption obtained was in the range of 540–1110 kJ kg−1 for 0.10 kg kg−1 dry‐basis moisture content and 52–108 kJ kg−1 for 0.25 kg kg−1 dry‐basis moisture content. CONCLUSION: These findings are technologically relevant for optimising common drying technologies such as flash and flatbed dryers. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A pneumatic drying model, developed in a previous work, was tested and validated based on a series of 56 experiments of cassava starch drying conducted on a pilot-scale pneumatic dryer. After fitting two parameters, the average diameter of starch particles and a heat loss factor, the model predicted the effects of main operating conditions with a level of accuracy comparable to that of the experimental measurements. Transient phases with sudden variations of product feed rate were also successfully simulated. The model is therefore suitable for equipment design purposes. The experimental results showed that the size of starch particles considerably decreases with increasing air velocity. As a result, at high air velocity, despite the shorter residence time in the drying pipe, the overall drying performance is improved due to the smaller particle size. It is therefore possible to increase air velocity, and hence product feed rate and production capacity, without detrimental effect on the drying efficiency. [ABSTRACT FROM AUTHOR]

Various cassava genotypes were developed with distinct starch characteristics, including amylose-free and small-granule mutations. Despite these unique traits, the ethanol production potential of these starches has not been explored. Cassava starch plays a crucial role in ethanol production, particularly in tropical countries like Colombia. This study aimed to assess the physicochemical properties of different cassava starches (including the amylose-free and small granule mutations), and to evaluate their potential for ethanol production using the Simultaneous Liquefaction, Saccharification, and Fermentation process under very high gravity (SLSF-VHG) and no-cooking conditions. Comparative analysis revealed that two double mutant starches and small-granule starch (GM4694–1) exhibited lower resistant starch content than those from wild-type and amylose-free cassava, making them more susceptible to enzymatic breakdown. The amylose content for GM4694–1 and wild-type cassava was 21.9 and 16.1 %, respectively, while the remaining samples were amylose-free. In the SLSF-VHG process, GM4694–1 demonstrated a significant ethanol yield, surpassing 16 % v/v, equivalent to 80 % of the theoretical ethanol yield within 90 hours. This suggests that the GM4694–1 genotype has the potential to produce ethanol efficiently at a temperature of 30°C. Furthermore, the solid residue obtained after the SLSF-VHG process could serve as a high-quality feed additive. This study enhances our understanding of the properties of special cassava starches and their correlation with ethanol production. [Display omitted] • Characterization of physicochemical properties of special cassava starches from the CIAT cassava breeding program. • Evaluation of ethanol production capacity by no-cook SLSF process at very high gravity. • The process using small-granule starch achieved a high 17 % v/v ethanol after 90 h, compared to 160 h for other starches. • Starch properties can predict the level of ethanol conversion. [ABSTRACT FROM AUTHOR]

Cassava production requires nitrogen (N) inputs to drive processes such as protein synthesis. Nevertheless, N not taken up by cassava roots is subjected to microbial transformation resulting in nitrous oxide (N2O) production, a potent greenhouse gas. The temporal dynamics of soil N is partially influenced by the N source (i.e., organic or inorganic fertilizer) and the synchrony between N supply and demand. This study, which was conducted in Colombia on soils with high organic carbon and phosphorus contents, aimed at monitoring N2O emissions from cassava plots fertilized with organic (49.8 kg N ha‐1 year‐1) or inorganic fertilizers (22.7 kg N ha‐1 year‐1). Although the organic fertilizer (vermicompost) contained more than double the amount of N, cumulative N2O emissions from organic cassava production (1.28 kg N2O‐N ha‐1) were lower than those from inorganic fertilizer‐based cassava production (1.74 kg N2O‐N ha‐1) system. This finding indicates that, if crop yields can be maintained, there is potential to reduce cassava production's environmental impact through organic fertilization on highly fertile soils. However, a transition to organic fertilization depends on the availability of sufficient amounts of organic fertilizers at the farm level. The N2O emissions in this study were higher than those predicted using the default IPCC emission factor, which confirmed the relevance of using country or regional specific emissions factors. [ABSTRACT FROM AUTHOR]

Consumers prefer cassava roots that cook quickly during boiling. Current methods to evaluate cooking time (CT) are slow and labour‐intensive. This article describes improved protocols for assessing CT in roots. We evaluated CT in 36 genotypes monthly at 8–11 months after planting. CT showed differences for plant age at harvest and among genotypes. During boiling, roots absorbed water (WAB) and thus reduced their relative density (DEN). We classified three groups of genotypes with increasing CT (≤25 min, 25–40 min and >40 min), associated with decreasing WAB, respectively, 15.3 ± 3.1, 10.7 ± 1.7 and 4.9 ± 3.8% of initial root weight. A similar trend was observed for changes in DEN (46.3 ± 9.8, 54.5 ± 11.1 and 75.9 ± 6.9% of initial DEN, respectively). The highest correlations between WAB and DEN with CT (r2 > 0.6) were found at 30‐min boiling. These alternative protocols facilitate screening large numbers of cassava genotypes for CT. [ABSTRACT FROM AUTHOR]

Summay: We studied the textural and rheological (viscoelastic) properties of fresh lafun dough, a fermented cassava product, and their changes during storage at 45 °C for 5 and 24 h, in order to determine after‐cooking storability. Lafun flours were produced from three types of cassava varieties: seven improved white‐fleshed varieties, seven improved provitamin A carotenoids (pVAC) varieties and two local white‐fleshed varieties; and processed into lafun doughs. Pasting properties of the flours were assessed. Flours from local varieties had pasting profiles with highest viscosities, while pVAC flours had the lowest. The three types of cassava varieties varied significantly in most of their pasting properties. Four promising improved varieties were identified, based on high peak viscosity (55.8–61.5 P) and stiffer texture than local varieties during storage. Undesirable varieties were also found, which softened during storage instead of hardening. Optimum texture of lafun dough was obtained after 5 h of storage. [ABSTRACT FROM AUTHOR]

Summary: The objective of this study was to characterise the nutritional potential of leaves and identify a diversity centre with low cyanide and high nutrient content among 178 Latin American cassava genotypes. This field‐based collection represents the seven diversity centres, held at The International Center for Tropical Agriculture (CIAT Palmira, Colombia) by the Cassava Program. The cyanide, all‐trans‐β‐carotene and lutein concentrations in cassava leaves ranged from 346 to 7484 ppm dry basis (db), from 174–547 μg g−1 db and 15–181 μg g−1 db, respectively. Cassava leaves also showed significant levels of essential amino acids leucine, lysine, phenylalanine, valine and threonine, and average total protein content of 26.24 g 100 g−1 db. Among seven diversity centres, South American rainforest group showed low cyanide and high carotene content in leaves. In addition, VEN77 and PAN51 genotypes stood out for having low cyanide in leaves and roots and high carotene in leaves. This genetic diversity can be used to select high potential progenitors for breeding purposes. [ABSTRACT FROM AUTHOR]

Summary: The purpose of this review is to support breeders and food scientists by examining research carried out on end‐user preferences for gari and its derived dough product, eba, in Africa. The review focused on gari regarding the physical and chemical composition of raw cassava roots, methods of storage, the composition of gari with or without enrichment, and the sensory evaluation of gari and eba. The primary sensory attributes identified to describe gari are colour, taste, texture, aroma and flavour. Texture attribute of importance is crispiness for uncooked gari, and hand feel before consumption for eba. There was a significant correlation between the sensory characteristics of gari and the starch and cyanogenic potential (CNP) contents of the raw roots. Hence, the correlation of the end‐user preferences with the chemical composition of the cassava roots could be helpful to breeders in refining selection criteria and developing high‐throughput screening methods. [ABSTRACT FROM AUTHOR]

Summary: The gari‐making process involves several unit operations (U.O.), some of which strongly influence the quality of the end product. Two contrasting process scales (laboratory‐scale vs conventional) were compared in order to identify which U.O. were affected by the change of scale. U.O. that changed end‐product characteristics depending on process scale were deemed critical; whereas U.O. that resulted in similar characteristics were deemed robust. The classification depended on quality attributes considered: rasping and roasting were critical for physical properties, in particular particle size which ranged from 0.44 to 0.89 mm between the two process scales; and robust for biochemical properties. In contrast, fermentation and pressing were critical for biochemical properties such as lactic acid content (0.93–1.88 g/100 g dry matter after pressing), which influences the perception of flavour, and robust for physical properties. This classification between critical and robust operations help quality control of gari, by pinpointing which U.O. control specific quality characteristics. [ABSTRACT FROM AUTHOR]

Summary: The review aimed to identify the different high‐throughput phenotyping (HTP) techniques that used for quality evaluation in cassava and yam breeding programmes, and this has provided insights towards the development of metrics and their application in cassava and yam improvements. A systematic review of the published research articles involved the use of NIRS in analysing the quality traits of cassava and yam was carried out, and Scopus, Science Direct, Web of Sciences and Google Scholar were searched. The results of the review established that NIRS could be used in understanding the chemical constituents (carbohydrate, protein, vitamins, minerals, carotenoids, moisture, starch, etc.) for high‐throughput phenotyping. This study provides preliminary evidence of the application of NIRS as an efficient and affordable procedure for HTP. However, the feasibility of using mid‐infrared spectroscopy (MIRS) and hyperspectral imaging (HSI) in combination with the NIRS could be further studied for quality traits phenotyping. [ABSTRACT FROM AUTHOR]

Summary: Consumers, traders and processors consider post‐harvest physiological deterioration (PPD) an important constraint. In Experiment 1, PPD was assessed three consecutive years in roots from five genotypes through seven storage days. PPD, scopoletin and dry matter content (DMC) was recorded during storage. Year, genotype, duration of storage and their interactions were significant. PPD was associated with duration of storage period, DMC and scopoletin contents. Ambient moisture and temperature during storage influenced PPD. In Experiment 2, roots from seven clones were harvested 10 months after planting from 30 consecutive biweekly plantings. PPD was assessed 0, 2 and 7 days after harvest. In 13 harvests, roots from plants pruned six days earlier were also evaluated. Results indicated large seasonal variation across genotypes. Pruning reduced PPD and DMC. Complex and contrasting relationships among the variables analysed were found. There is no uniform model explaining the relationship between PPD and the independent variables considered. [ABSTRACT FROM AUTHOR]

Cassava ( Manihot esculenta ) is the most important staple food in sub-Saharan Africa. However, the shelf-life of the crop is short and, for this reason, the roots are usually processed into more stable products like cassava flour by village-based enterprises. Most of these enterprises use small-scale locally built pneumatic dryers, but such dryers still need further development, so the objective of this research was to improve their energy performance. Experiments were conducted at two cassava processing centres, one in Tanzania and one in Nigeria. Sensors were installed on the dryers, product samples were collected and the mass and energy balance of the equipment analysed, allowing the dryers' minimum air mass flow rates to be calculated. The air mass flow rates of both dryers were then reduced to a level approximating the minimum value. In Tanzania, the air mass flow rate of the dryer was reduced by 24%, while in Nigeria it was reduced by 14%. In both locations, the modifications decreased the dryers' heat input without jeopardising evaporation rates, and so not affecting the final moisture content of the dry products. Air temperatures at the dryer outlets decreased and relative humidity increased, while enthalpy remained unchanged. The energy required to evaporate 1 kg of water decreased by 20% in Tanzania and by 13% in Nigeria. The modification also improved energy efficiency by 25% in Tanzania and by 14% in Nigeria. However, in Nigeria, where yellow cassava flour was being used, the dryer modifications resulted in greater product colour losses. [ABSTRACT FROM AUTHOR]

Exposure to air pollutants and heat stress from traditional cooking fires is the leading cause of mortality and morbidity in low- and middle-income countries globally and have an adverse effect on the environment. According to the World Health Organization, 3.8 million people die annually prematurely from illness related to household air pollution. Families living in poverty are at the highest risk, especially women and children. In this study, exposure to particulate matter (PM2.5 and PM10), carbon monoxide (CO) and nitrogen dioxide (NO2) was measured among resource-poor women cassava processors. The test locations were chosen in the peri-urban settlements of Abeokuta in the Ogun State of Nigeria, where household women entrepreneurs roast garri (granulated cassava) for sale in the local market. The measurements were taken for two types of stoves which are generally existing in the study location. First, a rectangular stove (RS) with two operators and, second, a circular stove (CS) with one operator; both stoves used wood as fuel. The emissions were compared with a modern mechanical liquefied petroleum gas burner-based garri roaster (GS). Hours spent per day in front of garri stoves ranged from 6 to 12 h for both stoves, with a frequency of 1 to 3 days of operation per week. It was found that CS operators were spending significantly more time in producing garri, which is due to the low capacity of the CS. The average PM2.5 concentrations for RS and CS were 381 and 273 μg/m3, respectively, estimated to be 21 and 41 μg/m3 on an annual mean level basis. Similarly, for PM10, the mean concentration levels were 1580 and 594 μg/m3 for RS and CS, respectively. The annual mean levels for PM10 were about 89 μg/m3 for both types of stoves. CO exposure during garri processing was up to five times higher than the recommended concentrations with a 4-h mean of 48 and 50 mg/m3 for RS and CS, respectively. NO2 levels were very low, ~ 0 ppm. This investigative research concluded that wood-fired small-scale garri producers in Nigeria are exposed to very unhealthy levels of PM, CO and thermal stress. The concentration levels of both PM and CO were exceeding the global as well as Nigerian ambient air quality standard regulations. Along with air pollution, thermal stress was a significant issue, which is known to exacerbate the negative effect of air pollution on the human body. [ABSTRACT FROM AUTHOR]

Cassava (Manihot esculenta Crantz) produces edible roots, a major carbohydrate source feeding more than 800 million people in Africa, Latin America, Oceania and Asia. Post-harvest physiological deterioration (PPD) renders harvested cassava roots unpalatable and unmarketable. Decades of research on PPD have elucidated several genetic, enzymatic and metabolic processes involved. Breeding populations were established to enable verification of robust biomarkers for PPD resistance. For comparison, these PPD populations have been cultivated concurrently with diversity population for carotenoid (β-carotene) content. Results highlighted a significant variation of the chemotypes due to environmental factors. Less than 3% of the detected molecular features showed consistent trends between the two harvest years and were putatively identified as phenylpropanoid derived compounds (e.g. caffeoyl rutinoside). The data corroborated that ∼20 μg β-carotene/g DW can reduced the PPD response of the cassava roots to a score of ∼1. Correlation analysis showed a significant correlation of β-carotene content at harvest to PPD response (R2 -0.55). However, the decrease of β-carotene over storage was not significantly correlated to initial content or PPD response. Volatile analysis observed changes of apocarotenoids derived from β-carotene, lipid oxidation products (alkanes, alcohols and carbonyls and esters) and terpenes. The majority of these volatiles (>90%) showed no significant correlation to β-carotene or PPD. Observed data indicated an increase (∼2-fold) of alkanes in varieties with β-carotene >10 μg/g DW and a decrease (∼60%) in varieties with less β-carotene. Fatty acid methyl esters with a chain length > C9 were detected solely after storage and show lower levels in varieties with higher β-carotene content. In combination with correlation values to PPD (R2 ∼0.3; P -value >0.05), the data indicated a more efficient ROS quenching mechanism in PPD resistant varieties. [Display omitted] • β-carotene (∼20 μg/g DW) can modulate PPD in cassava by reducing lipid oxidation and ROS. • There is an environment influence on cassava metabolism and PPD response(s). • Phenylpropanoid pathway has a significant involvement in PPD response(s) of cassava roots. [ABSTRACT FROM AUTHOR]

Structural and functional properties of starches from ensete pseudostems and water caltrop fruits were characterized and compared with other root and tuber (yam bean, taro, and cassava) and legume (chickpea and mungbean) starches. Taro and ensete starch granules were the smallest and largest, at respectively 2 μm and 42 μm average diameter. Amylose content varied from 7.91% in taro starch to 35.59% in chickpea starch with 19.20 and 20.85% in water caltrop and ensete starches. RVA analysis indicated that only water caltrop, mungbean, and chickpea starches had positive setback from peak, indicating strong gel formation. The dynamic rheological analysis also revealed high storage modulus ( G′) values upon cooling for these three starches. Ensete starch granules had the lowest susceptibility to α-amylase hydrolysis. Principal component analysis (PCA) confirmed substantial differences between the functional properties of these starches. These results demonstrate the potential of atypical starches to find value-added uses as food ingredients, either in pure form or as blends of various starches. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine and compare the melting (T m ), glass transition (T g ) and mechanical relaxation (T α ) temperatures of a new waxy cassava starch. Thermal transitions measurements were obtained by Differential Scanning Calorimetry (DSC) and Dynamical Mechanical Thermal Analysis (DMTA). The experimental data showed a high correlation between water volume fraction and melting temperature (T m ) indicating that the Flory–Huggins theory can be used to describe the thermal behavior of this starch. The T m of waxy cassava starch-water mixes were lower than a waxy corn starch-water reference system, but differences were not statistically significant. The mechanical relaxation temperatures taken at tan δ peaks were found 29–38 °C larger than T g . The T α and T g measured for waxy cassava starch exhibited similar properties to the ones of waxy corn starch, implying that waxy cassava starch can be used in food and materials industry. [ABSTRACT FROM AUTHOR]