The prickly pear fruit (Opuntia ficus indica L. Miller) belongs to the Cactaceae family.The fruit is a berry, composed by an epicarp and the pulp, which represents theedible portion. At maturation, the epicarp turns yellow, red or white, depending onthe cultivar. In Italy, the prickly pear is mainly cultivated in Sicily (90% of the nationalproduction). The fruit is very sensitive to low storage temperatures (< 5°C) which causechilling injuries. The fruits can be successfully commercialized as a ready-to-eat product,peeled and suitably packaged. The main limit to its production is the formationof off-flavours due to different factors, such as the growth of microorganism and theaction of endogenous enzymes (lipid oxidation). In fact, the oxidoreductases are directlyresponsible for the lipid oxidation, which has influence on the production of off-flavours,on the structure and on the shelf-life of the fruit. The lipoxygenase (LOX) is a dioxygenasewhich catalyzes the oxidation of polyunsaturated fatty acids to hydroperoxides.The aim of this work was to compare different packaging technologies to extend theshelf life of ready-to-eat prickly pear fruits. The LOX activity, microbial counts and gascomposition were evaluated for non-treated samples packed in ordinary atmosphereand in two modified atmospheres having different O2 and CO2 composition (MA1 5%O2, 2% CO2, 93%N2; MA2 2% O2, 5% CO2, 93% N2) and for samples treated either witha blanching or with a blanching followed by a dipping in a citric acid solution. Thepretreatment conditions are essential for the LOX activity, in particular the blanchingreduced its activity by at least 30% especially in combination with fruit acidification andlimited the microbial proliferation. As a result of suitable pretreatment and packagingoperations the shelf life of ready-to-eat prickly pears can be successfully extended.
|Numero di pagine||4|
|Rivista||Italian Journal of Food Science|
|Stato di pubblicazione||Published - 2012|
All Science Journal Classification (ASJC) codes