Residence time distribution studies in continuous thermal processing of liquid foods: a review

Abstract

This paper presents a review on residence time distribution (RTD) studies in continuous thermal processing of liquid foods. The theoretical basis of the Danckwerts analysis is summarized, as well as the most important flow models, with special emphasis on tubular systems. Methods for experimental determination, modelling and estimation of RTD are critically described. While main design objectives in continuous thermal processes may be guaranteed by a proper minimum residence or holding time, process optimization requires the knowledge of the residence time distribution. Both concepts are reviewed and discussed. A significant scatter was noticed among published results and the need ,for a systematic work is clear It was concluded that future research should focus on studies at pasteurizationlsterilization temperatures, as well as on studies conducted with real food products or model food systems with FIO~I-Newtoniun flow bchaviour: Furthermore. information relating RTD to processing conditions would be a useful tool for process optimization.

Residence time distribution in a single‐phase rotor–stator spinning disk reactor

“…When the integration interval exceeds six times the residence time (s 5 V R /Q), the measurement is discarded to prevent tailing dominated measurements. [21][22][23][24] Less than 2% of the measurements were discarded.…”

First International Conference on Resource Efficiency in Interorganizational Networks – ResEff 2013 –

“…However, it is not always possible to define the TRU in continuous processes directly. Instead, the focus should be on residence time (Pinheiro Torres & Oliveirah, 1998). Andersson & Pucar (1995) define "the residence time of the feed material as the expected time needed from entering at the input of the flow system to exiting at the output."…”

Heat and mass transfer modeling during continuous flow processing of fluid food by direct steam injection

“…The mean holding time of the flow and the product volumetric flow rate (τ = 3.5 s and Vj = 0.023 m 3 /s, respectively) reported in [22] were first employed to resume the vessel volume, by means of the relationships reported in the review by Pinheiro Torres and Oliveira [31]:…”