412 THE SPRINGING OP TINS OF PRESERVED FRUIT, 



It actively fermented fruit-syrup, and was undoubtedly the cause 

 of the springing of this particular tin. Another tin of pears 

 contained a mixture of inactive yeasts and moulds. As the}' 

 did not ferment fruit-syrup, it was clear that the cause of the 

 trouble had disappeared. A tin of greengages contained inactive 

 bacteria and moulds, and, as in the previous case, the agent 

 which had caused the fermentation had died or had been killed. 

 Several of the containers showed clear evidence of having leaked 

 at some time. 



A second lot of six faulty tins of pears was obtained in June, 

 1917, and the notes upon these are as follows. 



No.l. The container had a faulty lid, the tinplate was spong\', 

 and foaming syrup was oozing out of a central pin-hole. 'J'he 

 syrup was actively fermenting and contained yeasts. 



No.2, The container had a small quantity of syrup, the bulk 

 having apparently leaked out. The syrup contained yeasts and, 

 when set aside under aseptic conditions, it fermented vigorously. 



No. 3. The contents appeared to be normal, but the syrup con- 

 tained bacteria and yeasts. 



No. 4. The fruit appeared normal, but the syrup was thin, and 

 contained bacteria and yeasts. 



Nos.5 and 6. The contents were normal, and the syrup con- 

 tained bacteria only. 



All the containers, with the exception of No. 6, showed signs 

 of having leaked at some time. No. 6 was the only one that ap 

 peared to be intact. 



The bacteria in the tins were the same. On dextrose ajjar, 

 they grew as short, irregular rods, and hs chains, especially in 

 the condensed water. They were Gram-positive, and, as they 

 had no action upon any sugar, they could not have been respon- 

 sible for the springing of the retainers. 



The yeasts w^ere all of the culture-type, that is, they were 

 varieties of Saccharomyces cereinsice. This type is associated 

 with the manufacture of beer, and one would not expect to find 

 it in a factory where there is so much fruit utilised. In a factory 

 such as a fruit-cannery, wild yeasts and torulse should be present 

 in abundance, and it certainly was extraordinary to find only 



