Application of high pressure processing for prevention of greenish-gray yolks and improvement of safety and shelf-life of hard-cooked peeled eggs. (February 2018)

• Record Type: Journal Article
• Authors: Shahbaz, Hafiz Muhammad; Jeong, Bora; Kim, Jeong Un; Ha, Namho; Lee, Hyunah; Ha, Sang-Do; Park, Jiyong
• Is Part Of: Innovative food science & emerging technologies. Volume 45(2018)
• Page Start: 10
• Page End: 17
• Publication Date: 2018-02
• Subjects: Egg products -- High pressure post-processing -- Yolk color -- Salmonella Enteritidis; Food -- Biotechnology -- Periodicals; Food industry and trade -- Technological innovations -- Periodicals; Aliments -- Biotechnologie -- Périodiques; Food -- Biotechnology; Periodicals; Electronic journals; 664.005
• DOI: 10.1016/j.ifset.2017.09.016
• Languages: English
• ISSNs: 1466-8564

Abstract

Abstract: Hard-cooked peeled eggs (HCEs) are value-added ready-to-use egg products susceptible to microbial re-contamination during post-processing stages. A post-processing terminal step using high hydrostatic pressure (HHP 500, 550, 600 MPa for 5 min at 25 °C) was applied to ensure maximum safety of HCEs and the effects of processing were evaluated and compared with a commercial thermal post-processing intervention using steam heating. A significant discoloration in the form of greenish-gray yolks was observed in HCEs after steam heat post-processing due to overcooking. Color values of the HCE yolk (L*, a*, b*) after HHP post-processing were not significantly different (P > 0.05) from non-post-processed HCEs. Non-thermal and thermal post-processing interventions each kept the growth of microbial contaminants at < 10 4 CFU/g throughout 45 days of refrigerated storage. Microbial counts in non-post-processed HCEs exceeded this safety limit within 3 d. Sensory analysis showed significantly higher preference scores for the quality attributes of HCEs post-processed with HHP than with steam heating. Inactivation curves of Salmonella Enteritidis inoculated onto HCE surfaces after all HHP levels were well-fitted to the biphasic mathematical model. HHP post-package pasteurization at 550 MPa for 5 min showed potential as a terminal non-thermal kill step for commercial production of HCEs. Industrial relevance: A non-thermal post-processing intervention using HHP can be considered as a terminal kill step during commercial production of HCEs to ensure maximum microbiological safety and to extend the shelf life of HCEs without formation of unappetizing greenish-gray yolks. The biphasic mathematical model can be used to predict growth and survival of Salmonella Enteritidis in HCEs and to conduct a risk analysis of this type of food products. Highlights: HHP was applied as a post-processing intervention in hard-cooked peeled eggs (HCEs). HHP did not cause greenish-gray yolks in HCEs compared to thermal post-processing. HHP showed ability to inactivate Salmonella Enteritidis inoculated on HCE surface. HHP controlled microbial contaminants on HCEs surfaces during refrigerated storage. HHP terminal kill step can be applied in HCEs production to ensure microbial safety.