This research work was to study the improvement of toughness and impact resistance of polylactic acid (PLA) with modified soybean oil (MSBO) and palm fiber (PF). The detail of this work was divided into three parts. The first was to find the suitable condition for modification of soybean oil with ozonolysis. The second and last parts were to study the effects of MSBO and PF contents on the properties of PLA respectively. For oil modification the reaction times were varied from 0 to 3 hours and the chemical changes in molecules of soybean oil were investigated by Nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopies. The result suggested that the most suitable condition for ozonolysis reaction was 2 hours considering the decrease in double bond between carbon atoms and the increase in hydroxyl group into molecular structure of MSBO. For the effect of MSBO content on mechanical properties it was evaluated by tensile and impact testing. Differential scanning calorimeter (DSC) and scanning electron microscope (SEM) were used for thermal and morphology analyses. The result showed that elongation at break and impact strength of modified PLA by MSBO increased about 89 and 25 % compared to those of neat PLA respectively. MSBO act as the efficient plasticizer for PLA considering the conversion of fracture behavior from brittle to ductile good dispersions of MSBO droplets in PLA and the decrease of glass transition temperature (Tg) with addition of MSBO. The addition of PF improved the impact strength of modified PLA. Strong interfacial bonding between PLA and PF indicated MSBO being both coupling agent for PLA and natural fiber and plasticizer for PLA. For migration test it was found that contents of released heavy metal and migrated chemical from specimens of PLA and PLA/PF composite were under the criteria according to Notification of the Ministry of Public Health (No. 295) B.E. 2548.

Soybeans are a crop that can be utilized especially in terms of food rich in protein and fat as the human and animal needs. For using the soybeans must be processed to obtain the desired physical characteristics. The process is mostly a grinding and extraction. However these two processes are completely different applications. This research aims to study and create the soybeans grinder machine become to flour the quantity of grinding the variable that affect to the amount of grinding and economic analysis for guiding to investment. The researchers have designed the grinder unit by the coarse grinding and mill grinding unit. For the coarse grinding unit is similar to a disc and in case of grinding mill will be used the roller set. Base on the power train of bolt grinding unit the electric motor with 2 HP. at 1450 RPM are used for the experiment. For the grinding mil process the rough material is feed into grinding mil chamber for reduce the size of material become to the flour. The results of the research found that the suitable speed of the coarse grinding and mill grinding unit was 480 and 725 RPM respectively. In case of these relationships the average quantity of grinding for the coarse grinding and mill grinding unit was 271.8 and 150 kglhr respectively. Furthermore the results of experiment discover the materials that are not accounted of the coarse grinding for 13.9 percent. For the economic analysis for guiding to investment found that the breakeven point and pay-back period was 110378 kg and 0.0067 year respectively.

The purposes of the research on soy milk product mixed with carrot were to study the preparation of soy milk carrot juice extraction appropriate ratio of soy milk to carrot juice and sugar content shelf - life and consumers’ acceptance of the product. The study was focused on the product’s physical quality chemical composition sensory quality and micro-organism content. The results of the research revealed that soy milk with soy bean : water at 1:4 (by dry soy bean weight)used in extraction process; blanching of carrot prior to extracting which yields 70.31% of the juice and 4580 μg . (763.33 R.E) beta - carotene per 100 grams of carrot which is a higher amount than extracting fresh carrot ; the ratio of soy milk to carrot juice at 70:30 and 5% of sugar content by weight are appropriate in soy milk mixed with carrot production. The L*value a*value and b* value were 66.79 25.24 and 39.25 respectively. The viscosity was 17.33 centipoint; total soluble solid was 11.67 brix; and pH was 6.25. The acceptance scores on color flavour texture and overall preference were 7.98 8.00 7.93 and 8.05. This means preference on color and texture was moderate; the preference on flavour and texture was very high. For chemical composition it was found that there were 71.08 kcal. energy 4.40 g. protein 1.56 g. fat 9.86 g. carbohydrate and 1378 μg.(229.67 R.E.) beta-carotene per 100 grams. The cost of raw materials was 6.41 baht per 180 ml./bottle. The study of consumers’ product acceptance showed that most consumers had knowledge on nutrition; they accepted and had preference on the product at the moderate level. The price of 12.00 baht per 180 ml. bottle was accepted. It was also found that there was no physical or chemical change of the product when kept at 70C for 14 days. Total bacterial count was 4.8x10 CFU/cm3 when compared to Soy Milk Thai Community Product Standard (SPC. 529/2004) which specified that not exceeding 1x104 CFU/ cm3 should be found in the product. It was evident that the product was still safe for consumption when kept for 14 days.