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This study aimed to produce the degradable packaging from agricultural products and agricultural residues for useful and value added and developed the processing and forming machine on packaging production.
Start for researched the agricultural residues; husk of durian fruit (Cv. Monthong and Chanee) and banana piseudo-stem (Cv. Namwa and Khai). The agricultural residues were selected from best properties, which monthong husk and namwa pseudo-stem were selected because monthong husk had highest holocellulose content of 53.7%, pseudo-stem of namwa had highest of fiber length was 4.01 mm. Afterthat monthong husk and namwa pseudo-stem were extracted for cellulose using sodium hydroxide and then lignin removed with hydrogen peroxide. The percent yield of cellulose from husk of durian fruit and banana pseudo-stem were 21.51% and 20.25% whereas the yield of cellulose after bleaching were 84.80% and 74.75%. The cellulose of durian husk was selected to produce the degradable packaging; fiberboard, ethylene absorber paper and carboxymethyl cellulose (CMC).
Monthong husk fiber with 3%AKD was processed to 7 inch plate by hot compression molding at 160 ?C, 150 bar and 5 min. The plate from unbleached fiber was best forming than bleached fiber but plate from bleached fiber was best physical properties; density of 573.44 kg/m3, moisture content of 0.39%, thickness swelling of 89.68%, water absorption of 294.09% and time for absorption of 0.05 cm3 water was morethan 7 hrs. Mechanical properties of plate from unbleached fiber were compression strength at Top and bottom were 2.97 and 3.28 kF, burst strength of 419 kPa, puncture resistance of 0.66 J, tensile strength of 9.63 kN/m and elongation of 1.72%, which cannot test in plate from bleached fiber. The results indicated that properties of fiberboard plate from agricultural residues were lower than plate from bagasse but plate from bleached fiber had could be a potential for development.
Ethylene Absorber Paper (EAP) as active packaging for ethylene gas removal from agricultural products, which extend the duration of shelf life. The fiber (bleach and unbleached) of durian husk were produced to paper by sheet former. The suitable of fiber type was unbleached fiber because the paper was best properties, which following to Thai industrial standard: 170-2550 (55 grammage of Kraft Paper) except tensile strength. Afterward, unbleached fiber was prepared to EAP, which added with three different type of activated carbon viz. powder, granular and rod as ethylene absorber materials. Powder Activated Carbon (PAC) type was selected because mango kept in EAP with PAC had the lowest weight loss (10.55%) and could extend postharvest life of mango for 10 days at room temperature storage. Afterthat, demonstrated the suitable content of PAC added in EAP at 0, 5, 15, 25 and 35% (w/w) compared with commercial ethylene absorber. The results EAP with 5% of PAC shown greater extend postharvest life of mango for 15 days at room temperature storage and mango had lowest weight loss (28.59%) significantly different with other condition and commercial ethylene absorber. The properties of all EAP were following to Thai industrial standard: 170-2550 except tensile strength but can be improved by added dry strength agent. Cost of EAP with 5% PAC was 1.60 Baht/sheet while commercial ethylene absorber was 2-3 Baht/small pack. The results indicated that EAP from agricultural residues with 5% PAC had could be a potential for development.
Bioplastic from cellulose of husk of durian fruit was water soluble polymer. The cellulose powder from bleached fiber was then synthesized to carboxymethyl cellulose (CMC) by chloroacetic acid in alkaline condition. The percent yield of CMC was 138.12%. The obtained CMC powder had 95.63% purity and a degree of substitution (DS) at 0.68. It was water soluble with low viscosity at 429.9 cPs and appeared in pale yellow color. CMC solutions were added with four different additives viz. glycerol, sorbitol, polyethylene glycol and calcium carbonate at 10, 20, 30 and 40% (w/w) then it was casted to form the CMC film. The higher content of all additives resulted to the thicker film, greater elongation (%), poorer water solubility and lower tensile strength. The films formed with 30% glycerol had the highest elongation whereas film with 10% calcium carbonate highly resisted to tensile strength. The film with 40% calcium carbonate had the highest rate for oxygen transmission whist the properties of water solubility and elongation became low as compared to other treatments. Besides, all films were heat sealable and allowed oxygen transmitted through at rate of 1.15-17.6 cm2/m2/day. All CMC-based films could be degraded within 24 hour by burying it in high moisture content soil. Afterward, CMC films were processed to sachets for storing dry coffee powder. CMC-20% polyethylene glycol sachets could maintain quality of dry coffee power as similar as the coffee packed in aluminum foil bags at either ambient air or refrigerated storage. The results indicated that bioplastic derived from the husk of durian fruit could be a potential material for dry food packaging.
Agriculture products such as fruit and vegetable have been studied as potential film forming materials to be used as food bio-packaging and biofilm because of their chemical composition of polysaccharide such as pectin and cellulosic substance. Puree from fruits and vegetables were prepared and used as raw materials for film processing. Chemical compositions and film properties were determination. Among the purees, carrot showed the highest pectin, could produce the best film. The film’s properties was Improved by adding hydrocolloids, pectin and alginate at 1.5, 3 and 4.5% w/w of puree. The results showed that increasing concentration of both hydrocolloids were increased thickness, L*, tensile strength and water barrier (WVTR decreased) of film (P<0.05) while oxygen barrier of film were reduced (OTR increased). Film containing 3% alginate had better properties than other films. However, both of hydrocolloids could not improve elongation of films. So, xylitol at 1.25, 2.5, 3.75, 5 and 6.25% w/w of carrot puree were added to increased film’s elongation. The results showed increasing concentration of xylitol that increased thickness, water solubility, moisture content and elongation of film (P<0.05). On the other hands, tensile strength, water vapor barrier, L* and oxygen barrier of film were reduced (P<0.05). The higher levels xylitol caused the increased discolored of carrot film between storage. Afterward, carrot with 3% alginate and 3.75% xylitol was selected to form peanut toffee wrapper. During 6 weeks at 65% RH, peroxide value of samples that wrapped with carrot based film was slower increasing than samples that wrapped with wax paper and unwrapped.
Bio-packaging form cassava starch was determined for value added the cassava and produced the antimicrobial packaging for food. Cassava starch-chitosan blended film were prepared; mixed cassava starch solution with chitosan solution in starch:chitosan ratio (g): 1:0, 1:0.2, 1:0.4, 1:0.6, 1:0.8 and 1:1 and glycerol were added 40% w/w of total solid for plasticizers. The solution were casted in acrylic plate for forming. The result shown best forming, transparent films and the yellow color score (b*) was increase when increase chitosan. The properties of blend films were demonstrated. All of films shown best properties and significantly different (p<0.05); moisture content 9.51-10.45%, water activity (aw) 0.426-0.437, that shown the microbial can’t grow and water solubility 22.31-29.75%, which starch:chitosan 1:0.2 blend film was lower solubility. Afterthat, demonstrated the mechanical properties, water vapour transmission rate (WVTR) and oxygen transmission rate (OTR) of films. The results starch:chitosan 1:0.6 blend film shown higher tensile strength 134.2 kF/cm2, starch:chitosan 1:0 blend film shown higher %elongation 73.77%, starch:chitosan 1:0 blend film shown higher tear strength 590.16 mN, starch:chitosan 1:0 blend film shown higher WVTR and lower OTR, starch:chitosan 1:0.4 blend film shown lower WVTR and starch:chitosan 1:1 blend film shown higher OTR. The efficiency of blend films for antimicrobial packaging were tested. The result shown blend film couldn’t inhibit the Aspergillus flavus A39 growth, that didn’t have clear zone surrounded the piece of blend film. However, should other different microbial test in the future. Cost of blend film was 0.02-0.50 bath/sheet. The starch:chitosan 1:0.6 have potential for more researched on food packaging in the future because it have good properties same as film, that best properties (not significantly different).
Poly-?-hydroxybutyrate (PHB) is a type of the PHA family of polyesters. PHB has been detected in Cyanobacteria such as Spirulina sp., Nostoc sp., or Oscillatoria sp. This research work aims to collect Cyanobacteria from the samples of natural water basin and Corralloid roots of Cycas sp. investigates of biopolymer production of Cyanobacteria as raw material for biodegradable polymer production. Firstly, Cyanobacteria samples were collected from natural water basin using plankton net and Corralloid roots of Cycad. Then, they were isolated by observation of their cells under microscopes. The isolated of SM6-3 was collected from Corralloid roots of Cycas sp. of Queen Sirikit Park in Bangkok, Thailand. This isolate was identified as Nostoc sp. by Morphology. However, this strain showed a large of polyester’s droplets stained with Sudan Black B. Thus, this strain was selected to cultivate in BG-11 culture medium under indoor and outdoor cultivation with continues aeration. The results revealed that BG-11 that lack of nitrogen (N2-free medium) under outdoor condition was suitable for biopolymer production. The cell of Cyanobacteria was reached a maximum growth of 9.96 x 106 cell ml-1 within 18 days cultivation and the maximum biomass was 1.69 gL-1. After harvesting by centrifugal technique by using a high performance self-cleaning Separator, the biomass was extracted by Acid hydrolysis technique. Total PHB was presented as 0.33 gL-1 that was higher than cultivated with the normal BG-11 medium.
Moreover, Effect of bio-packaging materials on postharvest life of rambutan fruit was investigated. Three different bio-packaging materials viz. polylactic acid (PLA), polybutylene succinate (PBS) and Mater-Bi? were blown molded to be bags for containing one kg of rambutan fruit while low-density polyethylene (LDPE) bags were used as control group. There was no additive compound into PLA and PBS film during forming process. All films were measured for mechanical properties, water vapor and oxygen transmission rates, and biodegradability. Afterwards, rambutan fruits were randomly divided into four groups, packed in mentioned packaging and stored at 13?2oC with 78% RH. Mater-Bi? and PBS bags were easier to produce and use than PLA bags. The highest levels of both water vapor and oxygen transmission rates were detected in Mater-Bi? film followed by PBS and PLA bags, respectively. Percentage of elongation of Mater-Bi? in machine direction and transverse were significantly higher than other films whilst the tensile strength of Mater-Bi? was the lowest values in both machine direction and transverse followed by PBS and PLA, respectively. Mater-Bi? and PLA films took over 100 days to start degrading in moist soil whereas PBS film could degrade by 16 days and its degradation increased to 31.25% in 161 days. Rambutan kept in PBS bags had the lowest weight loss (%) with yellowish red color skin and fresh green spintern. The greater weight loss and brown skin appearance were found in rambutan packed in Mater-Bi? bags followed by fruit in LDPE. The results indicated that packaging made from PBS film could extend postharvest life of rambutan fruit for 15 days at 13?2oC storage.
According to above data, that shown the agricultural products and agricultural residues can be used to produce bio-packaging and active packaging, which have the potential to compete with the petrochemical packaging.
In addition, this research aims to develop a machine for preparing and forming agricultural residue for bio-packaging. Durian husk and banana pseudo-stem were selected for research, that difficult to prepared and take a lot of time. So be prepared to develop tools such as durian husk to slice a 2-4 mm. thickness has to be dried well and quickly. The design and construction of shredding fresh durian husk the casing enclosing the blades of two blades climb up on a stainless steel circular diameter of 30 cm. thick, 15 mm. mounted in a horizontal box, enter the second channel is a cylinder diameter of 7.6. cm high, 20 cm for enter durian peel down vertically. Use one electric motor power at blade speed 540 rpm that a rate of 392 kg per hour worked assume as 2 worker. The shredding machine for banana shown a work rate 1200 kg/hr. Speed Blade 1000 rpm. Break equivalent to using 16,963 kg per year, which compared to the wage rate 0.21 baht/.kg, running time 7 hrs/day (work rate of 1200 kg/hr).
The bio-packaging former as compression molding or dry heat compression machine, that using a hydraulic press. Forming machine, which was built with the ability to create hydraulic pressure of up to 30 MPa (306 kg.f/cm2) and mold heating part. The optimal conditions for the plate’s fibers from durian husk were 160 ? C for 5 min at pressures of 150 bar, with the ability to work forming press machine (Mold) Maximum size 400 x 400 x 150. mm3. Cost of forming packaging machines was 345,000 baht. If the price of bio-packaging 5.0 baht/piece, break at producing was 17,092 pieces/year will be payback time in 2,242 days.
Both of which can be applied to or further development of other types of agricultural waste.
Keywords: durian husk, banana pseudo-stem, fruit and vegetable puree, cyanobacteria,
poly-?-hydroxybutyrate, carboxymethyl cellulose, fiberboard, fiberboard plate, hydrocolloid, xylitol, ethylene gas, activated carbon, chitosan, peanut toffee, coffee, rambutan, additive, bioplastic, packaging, bio-packaging, active packaging, antimicrobial packaging, green packaging, isolation, cultivation, postharvest, storage life,
hydraulic press, dry press, hot press, mold |
