This research is to study the appropriate factors to increase the strength of the sealed packets containing seasoning sauce to experiments. This study began with the introduction of cause and effect diagram to analyze the factors that affect the s strength of seals. From the evaluation of several factors involved and found that the 3 factors may affect the strength of seals which are sealing temperature, speed in film feeding, and degree of shut-off valves. Therefore, an experimental design has been conducted by Central Composite Design to analyze the optimal conditions of the packaging, and using Response Surface Methodology to find the best value and it was found that the temperature sealing at 126 oC, film feeding 18 rpm and degree of shut-off valves at 115 degrees, given the maximum strength of the top and bottom seals. After the application of the experimental result, the strength of the sealing on top increased from 34 N to 56 N or 64.71% more, the standard deviation decreased from 3.14 to 2.92, or a decrease of 7.01% and the strength of seals at the bottom increased from the original 34 N to 55 N, or 61.77% more, the standard deviation decreased from 3.21 to 2.98, or decreased 7.17%. The result of improvement has determined to decrease the waste caused by sealing down from 81.5% to 3.68%, causing the waste of the packaging process reduce from 7.84% to 2.47% or down by 5.37% but the quality of seasoning sauce remain the same. This project has achieved the objective of the study

1. V. Vichit Tanthasut, W. Rijiravanich, and C. Mahittafongkul, Industrial Work Study. Bangkok, Thiland: Chulalongkorn University, 2000
2. W. Rijiravanich, Productivity in the Industry. Bangkok, Thiland: Chulalongkorn University, 2000.
3.  D. C. Montgomery, G. C. Runger, and N. F. Hubele, Engineering Statistics. New York, NY: Wiley, 2011.
4.  D. C. Montgomery, Introduction to statistical quality control. New York, NY: John Wiley & Sons, 2009.
5.  H. K. Celik, G. Kunt, A. E. W. Rennie and I. Akinci, “Non-linear fem-based shattering simulation of shelled edible agricultural products: Walnut shattering by nut cracker hand tool,” International Journal of Technology and Engineering Studies, vol. 3, no. 2, pp. 84–92, 2017. doi:10.20469/ijtes.3.40006-2
6.  K. Gopal Rao and R. Joseph V, “Reduction of testing of chemical parameter using design of experiments,” Quality Engineering, vol. 14, no. 2, pp. 301–305, 2010. doi: 10.1081/qen-100108687
7. K. Kankanok, B. Khamon, and P. Kongrod, “Study of waste reducing in packing process,” in Proceedings of Conference on Industrial Engineering Network, Cordoba, Spain, 2010.
8.  R. A. Bourque, Hot-Fill Technology. New York, NY: Wiley, 2000.
9. J. R. David, R. H. Graves, and T. Szemplenski, Handbook of Aseptic Processing and Packaging. Boca Raton, FL: Crc Press, 2012.
10. S. Tangsitcharoen and P. Jamchue, “Reduction of bubbles defects in plastic packaging plastic process: Utilizing box behnken experimental design,” in Proceedings Industrial Engineering Network Conference, Montréal, Canada, 2001.
11.  R. Coles, D. McDowell, and M. Kirwan, Plastic in food packaging. London, UK: Blackwell Publishing, 2003.
12.  R. H. Myers, D. C. Montgomery, and C. M. Anderson-Cook, Response surface methodology: Process and product optimization using designed experiments. Hoboken, NJ: John Wiley & Sons, Inc., 2009.
13. P. Chutima, “The experimental design engineering,” Chulalongkorn University, Bangkok, Thailand, Unpublsihed master’s thesis, 2004.
14. T. S. Parsana and M. T. Patel, “A case study: A process fmea tool to enhance quality and efficiency of manufacturing industry,” Bonfring International Journal of Industrial Engineering and Management Science, vol. 4, no. 3, pp. 145–152, 2014. doi: 10.9756/bijiems.10350
15. M. Guide, Data Analysis and Quality Tools. Pennsylvania, PA: Minitab Inc, 2000.
    
16. K. K. Chowdhury and E. V. Gopal, “Quality improvement through design of experiment. A case study, quality engineering,” in IFIP Network Conference, Paris, France, 2000.
17.  G. M. Smith, Statistical Process Control and Quality Improvement. London, UK: Prentice Hall, 2000.
    

B. Khamon, “study of factors affecting strength of sealing in the product packing process by utilizing central composite design,” International Journal of Technology and Engineering Studies, vol. 4, no. 3, pp. 77-85, 2018.