<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>Retort thermal sterilization of canned food is a technology, which allows preserving food products by applying heat on packaged food in retorts (autoclaves) at temperatures up to 121 °C. The thermodynamics of the processes in the retort are influenced by the product stacking method in the basket and packaging material. The aims of this study were: 1) to analyse and compare temperature distribution (TD) and the slowest to heat location in the steam-air retort stacked with glass jars and with retort pouches; 2) to analyse and compare commercial product heat penetration (HP) characteristics in glass jars and retort pouches. Temperature measurements were performed with wireless thermocouples. The come-up time (heating phase) required to achieve in the retort temperature uniformity criteria of ±0.5 °C, is 28 min when the retort is stacked with glass jars, and 24 min when the retort is stacked with retort pouches. Total calculated process time (holding phase), necessary to achieve the sterilization value (F<sub>0</sub> of 3 min), for sample in glass jars was 67 min, but in retort pouches – 62 min. The overall sterilization process time difference between two considered packaging types was 9 min, which is significant amount of time in the context of commercial processing. The study clearly shows the necessity to perform the Temperature Distribution and Heat Penetration study, as each packaging material, stacking method and product will affect sterilization process thermodynamics and, therefore, the overall process time and consequently - the safety of food product.</p>
</abstract>

Retort thermal sterilization of canned food is a technology, which allows preserving food products by applying heat on packaged food in retorts (autoclaves) at temperatures up to 121 °C. The thermodynamics of the processes in the retort are influenced by the product stacking method in the basket and packaging material. The aims of this study were: 1) to analyse and compare temperature distribution (TD) and the slowest to heat location in the steam-air retort stacked with glass jars and with retort pouches; 2) to analyse and compare commercial product heat penetration (HP) characteristics in glass jars and retort pouches. Temperature measurements were performed with wireless thermocouples. The come-up time (heating phase) required to achieve in the retort temperature uniformity criteria of ±0.5 °C, is 28 min when the retort is stacked with glass jars, and 24 min when the retort is stacked with retort pouches. Total calculated process time (holding phase), necessary to achieve the sterilization value (F0 of 3 min), for sample in glass jars was 67 min, but in retort pouches – 62 min. The overall sterilization process time difference between two considered packaging types was 9 min, which is significant amount of time in the context of commercial processing. The study clearly shows the necessity to perform the Temperature Distribution and Heat Penetration study, as each packaging material, stacking method and product will affect sterilization process thermodynamics and, therefore, the overall process time and consequently - the safety of food product.

A Case-study: Temperature Distribution and Heat Penetration in Steam-air Retort, Using Glass Jars and Retort Pouches

Latvia University of Life Sciences and Technologies

Rural Sustainability Research

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Retort thermal sterilization of canned food is a technology, which allows preserving food products by applying heat on packaged food in retorts (autoclaves) at...

A Case-study: Temperature Distribution and Heat Penetration in Steam-air Retort, Using Glass Jars and Retort Pouches

Published Online: Dec 22, 2021

Page range: 90 - 96

Received: Jun 29, 2021

Accepted: Nov 02, 2021

DOI: https://doi.org/10.2478/plua-2021-0020

Keywords
Process evaluation, process determination, CUT, holding time, autoclave processing

© 2021 Evalds Raits et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

A Case-study: Temperature Distribution and Heat Penetration in Steam-air Retort, Using Glass Jars and Retort Pouches

Published Online: Dec 22, 2021

Page range: 90 - 96

Received: Jun 29, 2021

Accepted: Nov 02, 2021

DOI: https://doi.org/10.2478/plua-2021-0020

KeywordsProcess evaluation, process determination, CUT, holding time, autoclave processing

© 2021 Evalds Raits et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
Process evaluation, process determination, CUT, holding time, autoclave processing