Journal de recherche et développement
Libre accès
ISSN: 2311-3278
ISSN: 2311-3278
Philippe Evon
Post-harvest tomato plants were accustomed manufacturefireboards by thermopressing. Four plant materials were investigated: exhausted tomato plants ground to 5-10 mm (PHTr), tomato (PHT) and maize (PHM) plants ground to <0.5 mm, composted tomato plants (CPHT). These materials had significantly different chemical composition, which significantly influenced the fireboards mechanical properties. The PHM fireboards containing the highest amount hemicellulose and water soluble sugars, and the lowest minerals‘ amount, performed best. The data allow estimating the role of each plant proximate in determining board mechanical behavior. Moreover, the findings of the work prospect a desirable integration of municipal and agriculture biowastes as a step forward toward the valorization of renewable organic matter and the realization of the zero waste objective.
Keywords:
Post-harvest plants; Tomato; Maize; Thermo pressing; Self-bonded fiberboards
Uncontrolled Keywords:
Post-harvest plants - Tomato - Maize - Thermo pressing - Self-bonded fiberboards
Abbreviations:
PHT Post-harvest tomato BPs Soluble biopolymers EVOH Polyethylene-co-vinyl alcohol
Introduction:
In the last twelve years, several papers have been published on the valorization of biowastes from municipal and agriculture sources as feedstock for the production of multipurpose speciality chemicals to be used in the chemical industry, agriculture and animal husbandry, for environmental remediation, and for the manufacture of materials. The wide range of applications arises from the fact that these chemicals are constituted by mixes of biopolymers (BPs) with molecular weight ranging from 5 to several hundred kDa .They contain organic C and N distributed over a variety of aliphatic and aromatic C moieties substituted by acid and basic functional groups, which are bonded to several mineral elements. These chemical features represent the memories of the protein, fats, polysaccharide, and lignin proximates constituting the pristine bio waste. They are associated to the BPs properties as surfactants, agents for sequestering or carrying small molecules and mineral ions in solution, photosensitizers and reactive biopolymers.
Highlights:
Bio based plastics from post-harvest tomato plants. Biopolymers from post-harvest plants and food wastes.Chemically processed versus raw post-harvest plants as feedstock to manufacture bio based plastics.
Blends of bio based materials and synthetic polymers from fossil sources.
Recycling renewable Cover the urban and agriculture environment.
Poly(vinyl alcohol-co-ethylene) was compounded with 2–10% post-harvest tomato (PHT) plant powder and processed by single-screw extrusion to yield composite films. Upon increasing the filler content, the values of the mechanical properties indicators were found to decrease as follows: Young's modulus from 1797 to 750 MPa, stress at yield from 36 to 15 MPa, maximal stress from 39 to 15 MPa, stress at break from 35 to 14 MPa, and strain at break from 6.6 to 4.3%. The results are discussed in comparison with other composite films containing poly(vinyl alcohol-co-ethylene) and water soluble biopolymers obtained by alkaline hydrolysis of fermented municipal biowastes, and with other commercial materials, such as starch based and low density polyethylene mulch films. Depending on the intended application, the post-harvest tomato blend films may be competitive for cost, performance and sustainability.
Experimental:
Post-harvest tomato and maize plant materials:
The post-harvest tomato (PHT) and maize (PHM) plant materials were obtained from the Lycopersicon Esculentum Cv. Naomi F1 tomato and Zea Mays maize [5] plants, respectively, which were collected at the end of the crop harvest season. The exhausted plants were pulled out of the soil, roughly ground to 5-10 mm size on site.
Chemical composition and thermal analyses:
The following analyses were carried out in duplicates according to known analytical methods: moisture and volatile solids by French standard NF V 03-903 , minerals by French standard NF V 03-322 cellulose, hemicelluloses and lignins by ADF-NDF method from Van Soest and Wine Water-soluble components were estimated through measurements of mass reduction of the test sample after 1 h in boiling water.
Statistical analyses:
All determinations were conducted in triplicates or quadruplets, and data are expressed as means ± standard deviations. The means were compared by the use of a singlefactor analysis of variance (ANOVA) using the GLM procedure of the SAS data analysis software
Results and Discussion:
Chemical composition of post-harvest plant materials:
chemical composition of the post-harvest plant materials used for manufacturing the fiberboards. It shows that PHM has the lowest relative content of mineral matter, low lignin content, the highest contents of cellulose and hemicelluloses, and a substantial amount of free sugars. On the contrary, CPHT has the highest minerals’ content. Compared to the post-harvest tomato raw (PHTr) and fine (PHT) matter, the higher mineral content of CPHT is the result of the mineralization of the pristine organic matter in the post-harvest tomato plants during composting. The data indicates that the organic matter loss due to composting results from the mineralization of the saccharide proximates. On the contrary, microbial degradation of recalcitrant lignin does not occur to much extent.
Conclusions:
The findings of this work evidence how the mechanical properties of materials made with post-harvest plant depend strongly on the composition of the native proximates. Due to the large variety of post-harvest plants and agriculture residues, which are available all year around, a wide range of ecofriendly materials may be fabricated. These will exhibit different responses to different types of mechanical stress. Thermopressing may therefore be a viable route to recycle native renewable matter for other uses.
Bottom line: This work is partly presented at 8th International Conference on Environmental Chemistry and Engineering September 20-22, 2018 Berlin, Germany/ Golden Tulip Berlin – Hotel Hamburg