W.  Jitjaroen, A.  Jitjaroen, A.  Suvannakita, O.  Bunthawong, 
    Performance Efficiency of In-line Stirred Yoghurt Machine Modeling for Use in SMEs,
    Journal of Engineering and Applied Sciences,
    Volume 9,Issue 6,
    2014,
    Pages 243-248,
    ISSN 1816-949x,
    jeasci.2014.243.248,
    (https://makhillpublications.co/view-article.php?doi=jeasci.2014.243.248)
    Abstract: A prototype in-line stirred yoghurt machine was designed and constructed for use in SME dairy plants and education establishments. The prototype consisted of mixer, pre-heater, pasteurizer, cooler, incubator and filling systems all necessary processes were aggregated within a 2.8 m<SUP>2</SUP> steel base. The operation of production was controlled by a set of Programmable Logic Controller (PLC) and/or one personal computer. Testing was done with a yoghurt mix. Results showed that the pasteurization system, using heat from a small gas burner transferred to the flowing raw milk through heat exchangers, destroyed all pathogenic microorganisms. Thereafter, the yoghurt mix was incubated in an insulated stainless steel tank at 42&deg;C for 3 h, then cooled to 20-25&deg;C over 30 min and total acidity of product was not &gt;0.76%. Production capacity was approximately 100 cups h<SUP>-1</SUP> by one operator. Overall, it was felt the prototype offered significant advantages in terms of its small size, portability and ease of operation. The 73% energy efficiency will also offer significantly reduced production costs.
    Keywords: Yoghurt;pasteurization;incubation;shell and tube heat exchanger;energy efficiency