Processo de descongelação de alimentos em restauração coletiva

Abstract

Temperature is one of the factors with highest impact in the food production and confection, due to its contribution to the activity and growth of microorganisms. Defrosting of edibles becomes one of the greatest problems of contract catering due to its inherent risks. According to the researched bibliography, food defrosting process should take place on a refrigerated environment, between 2ºC and 5ºC, and during the minimum possible time so undesirable processes can be controlled, as microorganism growth and food deterioration. This work emerged with the objective of understanding the impact of defrosting at environmental temperature in development and growth of microorganisms and its influence in food deterioration. To do this, the total microbial load was evaluated and some specific spoilage organisms: Enterobacteriaceae; Pseudomonas spp.; lactic acid bacteria (LAB) were studied. Samples of fish and meat were used, and the growth of this organisms on products submitted to defrosting was evaluated at environmental temperature (22ºC) in five different sample times: time zero, four hours, eight hours, twelve hours and twenty-four hours after defrosting. According to the obtained results, we can conclude that in both fish and meat samples, 24h after defrosting at environmental temperature, values of specific spoilage organisms above recommended were found. On the meat samples, there were levels above recommended of Pseudomonas spp and total microorganisms, with values of 108 UFC/g. For fish samples, the recommended values were exceeded for Enterobacteriaceae and LAB with values above acceptable. As suggested by bibliography, defrosting should be performed at refrigeration temperatures. Although accordingly to this study results until 12 hours of defrosting at environment temperature the analysed products were in between range of acceptable parameters of quality.

Date of Award	22 Mar 2023
Original language	Portuguese
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Ana Isabel de Almeida Roseira (Supervisor), Beatriz Justina Ferreira Ramos de Oliveira (Co-Supervisor) & Paula Teixeira (Co-Supervisor)