Abstrait

Effect of Exo-polysaccharides from different Penicillium sp. on quality of cloudy apple juice during storage

Gamil El-Sayed Ibrahim, Manal M.Housseiny, Heba I.Abo-Elmagd

In the present study, effect of exopolysaccharides of six Penicillium species on the quality parameters including: cloud stability, phenolic degradation, antioxidant activity, volatile and non-volatile compounds of cloudy apple juice were evaluated during storage for two weeks at 4 OC. The added exopolysaccharides showed increase in cloud stability and exhibited a dose-dependent free radical scavenging activity as shown by their DPPH radical and â-carotene assays. The volatile and non-volatile components of the selected treatment (Eup. pinetorum ATCC 14770) were performed using gas chromatography as well as Gas chromatography- Mass spectrometry and High performance liquid chromatography, respectively. Twenty-two volatiles, namely 16 esters, 2 alcohols, 2 aldehydes, 1 ketone and 1 monoterpene hydrocarbons were identified in the investigated samples. A total of 10 phenolic compounds were identified, the predominant compound was chlorogenic acid. This study revealed the value of exopolysaccharides as natural clouding and flavour stabilizer.