Effect of granular characteristics on the viscoelastic and mechanical properties of native chestnut starch (Castanea sativa Mill)

2015 ◽  
Vol 51 ◽  
pp. 305-317 ◽  
Author(s):  
André M. Lemos ◽  
Ana S. Abraão ◽  
Bruno R. Cruz ◽  
Maria Luísa Morgado ◽  
Magda Rebelo ◽  
...  
2013 ◽  
Vol 43 (2) ◽  
pp. 200-207 ◽  
Author(s):  
M. Romagnoli ◽  
S. Spina

Ring shake is a defect that strongly affects chestnut (Castanea sativa Mill.) use and its occurrence is known to be mainly related to mechanical stress within a tree; however, few investigations have compared the physico-mechanical properties of healthy and shaken trees. Hence, the aim of this study is to compare the density, compression strength, bending strength (MOR), and shrinkages between healthy and shaken trees in coppice stands. The investigation was carried out in the Lazio Region in central Italy in trees with a cambial age between 6 and 25 years. The results showed that shaken trees had lower mechanical strength and shrinkages than healthy ones and that the physico-mechanical parameters might be used to predict ring shake occurrence in a specific geographic area. Geographical location strongly affected the physico-mechanical properties of the chestnut wood, and this factor influenced ring shake occurrence. MOR value was assumed to be the parameter that could be applied at almost all study sites to distinguish between shaken and healthy trees. There was no difference between the shaken and healthy portions of a disk inside the same tree.


2013 ◽  
Vol 94 (1) ◽  
pp. 594-602 ◽  
Author(s):  
Bruno R. Cruz ◽  
Ana S. Abraão ◽  
André M. Lemos ◽  
Fernando M. Nunes

2001 ◽  
Vol 44 (1) ◽  
pp. 69-78 ◽  
Author(s):  
Ivo Mottin Demiate ◽  
Marília Oetterer ◽  
Gilvan Wosiacki

Studies were conducted to characterize the chestnut and its starch. Chemical composition of the chestnuts showed high level of starch. Moisture level in the raw nuts was around 50g/100g in wet basis and starch content, around 80g/100g in dry basis; other nut flour components were protein (5.58 g/100g), lipid (5.39 g/100g), crude fiber (2.34 g/100g) and ash (2.14 g/100g). Starch fraction was chemically characterized in order to identify the granule quality as compared with those of cassava and corn. This fraction showed more lipids and proteins than the other starches. Chestnut starch granules showed peculiar shape, smaller than the control starches and low amount of damaged units. Chemical composition concerning amylose : amylopectin ratio was intermediate to that presented by cassava and corn starch granules. Water absorption at different temperatures as well as solubility were also intermediate but closer to that presented by cassava granules. The same behavior was observed in the interaction with dimethyl-sulfoxide. Native starch granules and those submitted to enzymatic treatment with commercial alpha-amylase and also with enzymes from germinated wheat were observed by scanning electronic microscopy. Water suspensions of chestnut starch granules were heated to form pastes that were studied comparatively to those obtained with cassava and corn starches. Viscographic pattern of chestnut starch pastes showed a characteristic profile with high initial viscosity but peak absence, high resistance to mechanical stirring under hot conditions and high final viscosity. There was no way to compare it with the paste viscographic profiles obtained with the control starches. Chestnut starch pastes were stable down to pH 4 but unstable at pH 3. The water losses observed in the chestnut starch pastes after freeze-thaw cycles showed more similarity to the pattern observed in corn starch pastes as well as clarity and strength of the gel. In general the results showed that chestnut pastes functional properties are intermediate to those of the cassava and corn starch pastes.


Forests ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 73
Author(s):  
Maurizio D’Auria ◽  
Marisabel Mecca ◽  
Maria Roberta Bruno ◽  
Luigi Todaro

Improvements in the yield and solubility of chestnut wood extractives, by using different extraction methods and molybdenum catalysts as support, have rarely been reported in literature. Many studies focus on the different parts of trees, except for the chemical characteristics of the remaining extractives achieved from thermally modified (THM) chestnut (Castanea sativa Mill) wood. This research seeks to better understand the effects of extraction techniques and catalysts on the yield and solubility of extractives. GC-MS analysis of the chloroform soluble and insoluble fractions was also used. Accelerated Solvent Extraction (ASE) 110 °C, Soxhlet, and autoclave extraction techniques were used to obtain extractives from untreated and thermally modified (THM) chestnut wood (170 °C for 3 h). Ethanol/H2O, ethanol/toluene, and water were the solvents used for each technique. A polyoxometalate compound (H3PMo12O40) and MoO3 supported on silica were used as catalysts. The THM induced a change in the wood’s surface color (ΔE = 21.5) and an increase in mass loss (5.9%), while the equilibrium moisture content (EMC) was reduced by 17.4% compared to the control wood. The yields of the extractives and their solubility were always higher in THM and mainly used ASE as the technique. GC-MS analysis of the extractives, without catalyst support, showed different results for each extraction technique and type of wood (untreated and THM). Ultimately, the amount of extractive compound dissolved in each solvent will differ, and the choice of extraction technique will depend on the intended final application of the extracted chemical product.


Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 231
Author(s):  
Mariam Gaidamashvili ◽  
Eka Khurtsidze ◽  
Tamari Kutchava ◽  
Maurizio Lambardi ◽  
Carla Benelli

An optimized cryopreservation protocol for embryonic axes (EAs) of chestnut (Castanea sativa Mill.) has been developed based on the encapsulation–vitrification procedure. EAs of mature seeds were aseptically dissected and encapsulated in alginate beads with or without 0.3% (w/v) activated charcoal (AC). Embedded EAs were dehydrated with Plant Vitrification Solution 2 for different treatment times up to 120 min, followed by direct immersion in liquid nitrogen. Cryopreserved embryonic axes encapsulated with AC showed higher survival (70%) compared to those encapsulated without AC (50%). Sixty-four percent of embryonic axes, from synthetic seeds with AC, subsequently developed as whole plants. Plantlet regrowth was faster in AC-encapsulated EAs and showed enhanced postcryopreservation shoot and root regrowth over 2 cm after five weeks from rewarming. Results indicate that encapsulation–vitrification with activated charcoal added to the beads is an effective method for the long-term preservation of Castaneasativa embryonic axes.


Agronomy ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 109
Author(s):  
Theocharis Chatzistathis ◽  
Evgenia Papaioannou ◽  
Anastasia Giannakoula ◽  
Ioannis E. Papadakis

One of the most challenging topics for the sustainable agriculture is how to decrease high fertilization rates. A pot experiment, exploring the effects of zeolite (ZEO) and/or vermiculite (VER) as soil amendments, comparing to the soil application of a controlled release fertilizer (CRF), was realized in chestnut plants. Various parameters related to soil fertility, and plant growth, nutrition, and physiology were investigated to gain knowledge towards more sustainable management. After ZEO application and in comparison to CRF, an impressive boost in soil K was achieved. Moreover, soil P and Zn levels were higher in the VER-treated soil, compared to CRF. Leaf K and Ca concentrations were significantly higher in ZEO, compared to the VER treatment; the highest foliar N and Zn concentrations were measured in CRF and VER, respectively. However, significantly lower foliar Mn and Cu were found in VER. The highest root biomass produced in the ZEO treated plants. For most nutrients, their total uptake per plant was higher in CRF and ZEO. Finally, photosynthetic rates were higher in VER (mainly due to non-stomatal factors) and CRF (mainly due to stomatal factors). Our data open a discussion towards the application of ZEO and/or VER as soil amendments in chestnut nurseries and orchards, aiming at partially decreasing fertilization rates and boosting sustainable nutrient management.


Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1538
Author(s):  
Ana Teresa Alhinho ◽  
Miguel Jesus Nunes Ramos ◽  
Sofia Alves ◽  
Margarida Rocheta ◽  
Leonor Morais-Cecílio ◽  
...  

The sweet chestnut tree (Castanea sativa Mill.) is one of the most significant Mediterranean tree species, being an important natural resource for the wood and fruit industries. It is a monoecious species, presenting unisexual male catkins and bisexual catkins, with the latter having distinct male and female flowers. Despite the importance of the sweet chestnut tree, little is known regarding the molecular mechanisms involved in the determination of sexual organ identity. Thus, the study of how the different flowers of C. sativa develop is fundamental to understand the reproductive success of this species and the impact of flower phenology on its productivity. In this study, a C. sativa de novo transcriptome was assembled and the homologous genes to those of the ABCDE model for floral organ identity were identified. Expression analysis showed that the C. sativa B- and C-class genes are differentially expressed in the male flowers and female flowers. Yeast two-hybrid analysis also suggested that changes in the canonical ABCDE protein–protein interactions may underlie the mechanisms necessary to the development of separate male and female flowers, as reported for the monoecious Fagaceae Quercus suber. The results here depicted constitute a step towards the understanding of the molecular mechanisms involved in unisexual flower development in C. sativa, also suggesting that the ABCDE model for flower organ identity may be molecularly conserved in the predominantly monoecious Fagaceae family.


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