Native and fermented waxy cassava starch as a novel gluten-free and clean label ingredient for baking and expanded product development.

Amylose-free and wild-type cassava starches were fermented for up to 30 days and oven- or sun-dried. The specific volume (ν) after baking was measured in native and fermented starches. The average ν (across treatments) for waxy starch was 3.5 times higher than that in wild-type starches (17.6 vs. 4.8 cm3 g-1). The best wild-type starch (obtained after fermentation and sun-drying) had considerably poorer breadmaking potential than native waxy cassava (8.4 vs. 16.4 cm3 g-1, respectively). The best results were generally obtained through the synergistic combination of fermentation (for about 10-14 days) and sun-drying. Fermentation reduced viscosities and the weight average molar mass led to denser macromolecules and increased branching degree, which are linked to a high loaf volume. The absence of amylose, however, was shown to be a main determinant as well. Native waxy starch (neutral in taste, gluten-free, and considerably less expensive than the current alternatives to cassava) could become a new ingredient for the formulation of clean label-baked or fried expanded products.

Genome Analysis and Pathobiology of Cassava-Infecting Torradoviruses Containing a Putative Maf/HAM1 Pyrophosphatase Domain.

Next generation sequencing has been used to identify and characterize the full genome sequence of a cassava-infecting torradovirus, revealing the presence of a Maf/HAM1 domain downstream of the RNA-dependent RNA-polymerase (RdRp) domain in RNA1 in all isolates sequenced. A similar domain is also found in unrelated potyvirids infecting Euphorbiaceae hosts in the Americas and cassava in Africa. Even though cassava torrado-like virus (CsTLV) could not be mechanically transmitted to a series of herbaceous hosts, it can be efficiently transmitted by bud graft-inoculation to different cassava landraces. Our bioassays show that CsTLV has a narrow host range. Crystal-like structures of isometric virus-like particles were observed in cells of plants with single infection by CsTLV, and consistently induced chlorotic leaf spots and affected root yields significantly. Moreover, CsTLV infection induces changes in the accumulation of total sugars in storage roots. Field surveys indicated the presence of CsTLV in the main cassava growing regions of Colombia, and the occurrence of two different cassava-infecting torradovirus species. Profiles of small RNAs of 21 to 24 nucleotides in length, derived from CsTLV RNAs targeted by cassava RNA silencing defense mechanisms, are also reported.

Correlation of cooking time with water absorption and changes in relative density during boiling of cassava roots.

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 (r 2 > 0.6) were found at 30-min boiling. These alternative protocols facilitate screening large numbers of cassava genotypes for CT.

Near-infrared spectroscopy applications for high-throughput phenotyping for cassava and yam: A review.

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.

A comparison study of five different methods to measure carotenoids in biofortified yellow cassava (Manihot esculenta).

The most commonly used method for measuring carotenoid concentration is high-performance liquid chromatography (HPLC). Nevertheless, easier, quicker, and less costly proxy methods exist. We aimed to determine the diagnostic performance of several proxy methods: the spectrophotometer, iCheck Carotene, and near-infrared spectroscopy using both a desktop (dNIRS) and a portable (pNIRS) device for the measurement of total carotenoid concentration (TCC) and all-trans-ß-carotene concentration (trans-BC) in 30 fresh cassava (Manihot esculenta Crantz) storage roots in comparison with HPLC. The spectrophotometer presented the highest predictability for TCC, followed by iCheck, dNIRS, and pNIRS. The dNIRS showed the highest predictability and agreement for trans-BC. The pNIRS showed the poorest repeatability and greatest underestimations compared with HPLC. The agreement between all methods was lower for higher carotenoid concentration, with the exception of the spectrophotometer. According to our results, and for screening purposes, the measurement of carotenoids in fresh cassava roots can be carried out by spectrophotometer, iCheck Carotene and NIRS methods depending on the availability of equipment.