Encontro de Energia no Meio Rural
AGRENER

Abstract

AFONSO, Marcos R. A. and SILVEIRA JR., Vivaldo. Resfriamento rápido a vácuo de alfaces (Lactuca Sativa L.). In Proceedings of the 3. Encontro de Energia no Meio Rural, 2000, Campinas (SP, Brazil) [online]. 2003 [cited 05 May 2024]. Available from: <http://www.proceedings.scielo.br/scielo.php?script=sci_arttext&pid=MSC0000000022000000100014&lng=en&nrm=iso> .

Vacuum cooling is a method of fast cooling indicated for leafy vegetables. This method of cooling has been successfully applied to produces as lettuce, cabbage, cauli-flower and spinach. The main advantages are the cooling time and uniformity of the final temperature. In this present work heads of lettuce (Lactuca Sativa L.) were vacuum cooled. The influence of processing time, lettuce weight, pumping speed, initial temperature and prewetting on the final pressure, on final temperature, and on weight loss were investigated by experimental design. The smallest temperatures reached were 4.7^oC with 4.5% of weight loss in nonprewetted lettuce and 5.0 ^oC with 1.71% of weight loss in prewetted lettuce, in 40 minutes of process.

Keywords : Resfriamento a vácuo; Resfriamento rápido; alface.