Firmness of 60 apples (Kohanz GOLAB local variety)during 10 weeks storage at 2 and 85% RH was evaluated using non destructive acoustic and destructive penetration tests. Aim of this study was , determine of Golab apple firmness by two methods of acoustic test and puncture test during storage. Values of firmness index for apples in storage time changed between 21.76-8.44(×106Hz2gr2/3).To find the dominant frequency of apples ,by a pendulum device, non destructive impulses was hit to apples and by a hand held analyzer, related waves were recorded and to determine penetration firmness on apples ,was used texture analyzer. Decreasing linear functions of acoustic parameters and penetration firmness , estimated firmness of apples. Furthermore a linear relation, between acoustic parameters and penetration measurements obtained and the correlation between them , was found. The results obtained in this study showed, acoustic technique, compared with puncture technique ,is more sensitive for representation of firmness changes of apples in during storage life.

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