CAUSE OF EXPLOSION IN CHOCOLATE CANDIES 603 



heavy platinum needle. The opening was then sealed with 

 melted chocolate, and the samples incubated at room tempera- 

 ture. None of the chocolates exploded when incubated for 

 fifteen days. It seemed probable that the chocolates used had 

 evaporated too much of their moisture content to permit growth 

 of the organisms. 



The experiment was then repeated by inoculating the culture 

 into the fondant just before dipping. The freshly dipped and 

 inoculated chocolates were then carried to the laboratory and 

 incubated at room temperature as before. On the tenth day 

 the inoculated chocolates were found exploded, while the con- 

 trols remained intact after several months. The fondant con- 

 sisted of egg white, sugar, butter and ground walnuts. 



The experiment was repeated by adding cultures of Bad. 

 coll and Sacch. cereviceae. The chocolates inoculated with 

 Bad. coli failed to explode after prolonged incubation, but those 

 inoculated with the yeast as well as those inoculated with B. 

 sporogenes were found exploded on the tenth day. The controls 

 remained intact. The findings indicate that the yeasts found 

 in one of our earlier analyses were perhaps not without signi- 

 ficance. Apparently too, more than one type of organism is 

 capable of producing gaseous fermentation with consequent ex- 

 plosion of the chocolates. We have no evidence to show that 

 the Bad. coli type of organism is ever causally related to this 

 phenomenon since it was never found in exploded chocolates, 

 and inoculation experiments were negative. 



SUMMARY 



1. Chocolate candies are subject to explosion due to the 

 development of gas-forming microorganisms within them. This 

 tj'pe of explosion should be distinguished from mere cracking 

 due to rough handUng of the candies. 



2. Anaerobic bacteria of the type of B. sporogenes are the 

 chief cause of explosion in chocolates, but yeasts may also cause 

 the phenomenon. Apparently the Bad. coli type of organisms 

 is not involved. 



