and enhanced CO 2 levels and appropriate conditions need to be esta-
blished for each commodity.
Canned fruits are normally given a relatively low heat treatment
because of their low pH and although most mould propagules would
be killed the ascospores of some members of the Eurotiales are suffi-
ciently heat resistant to survive. Species ofByssochlamysare the best
known but the increasing use of more exotic fruits is providing
cases where spoilage of canned fruits have been due to such organisms
asNeosartorya fischeri(anamorphAspergillus fischerianus) andTalaro-
myces flavusvar.macrosporus(anamorphPenicilliumsp.).
5.5.5 Vegetables and Vegetable Products
The higher pH values of the tissues of many vegetables makes them more
susceptible to bacterial invasion than fruits although there are also a
number of important spoilage fungi of stored vegetables. The bacteria
involved are usually pectinolytic species of the Gram-negative genera
Pectobacterium, PseudomonasandXanthomonas, although pectinolytic
strains ofClostridiumcan also be important in the spoilage of potatoes
Figure 5.9 Examples of antifungal biocides which may be used to protect fruits from
mould spoilage
Chapter 5 153