Taking just a few seconds to coolfreshly laid eggscould add calendar week to their shelf life story , according to a study from Purdue University .
The speedy - cooling operation , modernise by Kevin Keener , Ph.D. , a nutrient skill prof at Purdue , utilise fluent carbon dioxide to stabilize the proteins in egg egg white , so much that they could be rated AA — the high grade for eggs — for 12 weeks . Eggs cooled under current methods drop off the AA grade in about six weeks .
accord to Keener , freshly laid testicle and rapidly chill ball at 12 weeks measured by the Haugh trial — units used to measure an egg white ’s protein lineament — showed statistical differences .
“ This speedy - cooling summons can provide a important extension in the shelf life-time of eggs equate to traditional processing , ” Keener says .
Keener ’s results , published in the daybook Poultry Science , also show that membranes surrounding the eggs ’ yolk were maintained for 12 weeks when testicle were chop-chop cooled . The tissue layer assist as a roadblock to keep harmful bacteria from reaching the egg yolk , a nutrient - rich reservoir that bacterium could use as a food beginning .
“ The structural unity of the yolk membrane stays strong longer , which may provide a food safety benefit , ” Keener say . “ The tissue layer being impregnable would be another defending team against bacterial encroachment , such as salmonella . ”
The rapid - cool down engineering takes fluid carbon dioxide and turns it into a “ snow ” to rapidly lower the eggs ’ temperature . Eggs are position in a cool down chamber at about minus 110 grade F , and carbon dioxide gas is yield . The cold gas is circulated around the eggs and forms a thin layer of ice inside the shell . After treatment , the ice layer melts and quickly lower an testis ’s intimate temperature to below 45 degrees F , the temperature at which salmonella can no longer grow .
Keener ’s previous enquiry showed that the carbon dioxide in bicarbonate form significantly increase the bodily process of muramidase , an enzyme in the egg white that has bactericidal properties .
Traditionally , eggs are at more than 100 level F when placed into a cartonful . Thirty dozen eggs are then packed in a instance , and 30 cases are stacked onto pallets and placed in refrigerated coolers . The eggs in the middle of the pallet can take up to 142 hours — nearly six days — to cool down to 45 degrees , Keener says .
A 2005 U.S. government composition showed that if eggs were cooled and store at 45 grade within 12 60 minutes of laying , there would be about 100,000 few salmonella illnesses from eggs in the res publica each year .
Keener say with additional funding , he would keep to study the benefit of rapid cooling system , including inoculate the interior of shell eggs with salmonella and examining how other proteins in the whites and yolk of testis are affected .
Keener is a technical consultant to the American Egg Board and a fellow member of the United Egg Producers Scientific Advisory Panel . His work was fund by Purdue and gift funds .
