MODEL MATEMATIK PERPINDAHAN PANAS DAN MASSA SERTA PERUBAHAN KARAKTERISTIK PRODUK SELAMA PROSES PENGGORENGAN BUAH PADA KEADAAN VAKUM

• Main Authors: , Jamaluddin, Drs.,MP., , Prof. Dr. Ir. Budi Rahardjo, MSAE
• Format: Theses and Dissertations NonPeerReviewed
• Published: [Yogyakarta] : Universitas Gadjah Mada 2011
• Subjects: ETD
• Online Access: https://repository.ugm.ac.id/89358/; http://etd.ugm.ac.id/index.php?mod=penelitian_detail&sub=PenelitianDetail&act=view&typ=html&buku_id=51285
• Institution: Universitas Gadjah Mada

Recently, fruit flaky product from vacuum frying process has been popularly consummed by people, because product�s characteristics are puffing, natural color, hard texture and crunchy while being eaten. To meet the characteristics of fruit flaky product being suitable with the consummer taste, it is necessary to consider characteristics and process condition, and also raw material changes. During the frying process, heat and mass transfer simultanously occur that causes many physical and chemical changes in fried fruit. The physical changes in product are water vaporization, oil absorption, shorten the cooking time, development of the crispiness and taste, changing of volume, texture, and taste, whereas the chemical changes in product are gelatinizing starch, and product color change. The main objectives of this research consist of four aims. Firstly, developing simultaneous heat and mass transfer mathematical model of jack fruit during vacuum frying. Secondly, developing jack fruit volume and density change ratio mathematical model during vacuum frying by considering water and starch content degradation/reduction. Thirdly, developing fruit hardness and crunchiness mathematical model during vacuum frying by considering water and starch content reduction. Fourthly, developing mathematical model of fruit color changes (L, a, and b) during vacuum frying by considering water and sucrose content reduction in product. Research samples are jack fruits vacuumly fried at 70 � 100 Heat and mass transfer model involves changes of water, oil, starch, sucrose, glucosa reduction, and β-carotene content in product. Model reconstruction is based on concept of �lump capacitance�. The form of model is a one order simultaneous differential equation solved by Runge-Kutta numerical method. The observed parameters are the contents of water, starch, sucrose, glucosa reduction, β-carotene, volume, density, texture, and sample color before and after being fried. The simulation results of increasing temperatur, water content reduction and oil absorption of product during vacuum frying describe that the developed mathematical models are appropriate to explain simultaneous heat and mass transfer phenomena in vacuumly fried fruit. Computation results of volume change and density change ratio showing that the developed models could predict volume change and ratio of density change during vacuum frying caused by water vaporization and starch content reduction. Besides, from the calculations of product hardness and crunchiness changes using models showed that the developed model could be utilized to reveal the changes of hardness and crunchiness caused by water vaporization and starch content reduction in product O C, frying duration of 15 � 60 minutes, and vacuum pressure of 13 � 23 kPa. during vacuum frying. Based on color change calculation result (L, a, and b) showed that the developed color (L, a, and b) change model can be used to explain color changes (L, a, and b) that were caused by water and sukrosa content reduction in product during vacuum frying.