An investigation of uncertainties in determining convective heat transfer during immersion frying using the general uncertainty management framework

Research output: Contribution to journalArticle


Although extensively studied (and of large importance for food processing) there is still no general consensus on the time-dependent convective heat transfer coefficient (h) in immersion frying – reported values differ by orders of magnitude (4–7000 W m−2 K−1). Moreover, none of the many methods suggested have become a generally agreed upon standard. This study uses the general uncertainty management (GUM) framework to analyze the standard uncertainties in four commonly used methods to measure h in immersion frying. It is concluded that the uncertainties (when including all sources of uncertainty in a systematic manner using the GUM) are often substantially larger than previously reported (up to 100% relative uncertainty), i.e., some methods used in previous studies are very sensitive to measurement uncertainties. This can help explain the large variation in previously reported h-values. Comparisons between methods suggest that evaporation rate based methods (with numerical differentiation) provide the highest reliability.


Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Food Engineering


  • Convective heat transfer, Deep-fat frying, Experimental design, Heat transfer coefficients, Immersion frying, Uncertainty management
Original languageEnglish
Pages (from-to)424-436
Number of pages13
JournalJournal of Food Engineering
Publication statusPublished - 2019 Dec 1
Publication categoryResearch