This paper describes studies of the microbiological quality and physicochemical properties of high pressure processed apple desserts. The desserts were produced from fresh apples of excellent quality. After removing useless parts, the fruits were washed, crumbled by cutting and then mixed with pectin acid and sugar or Aspartame at room temperature. Individual portions of dessert were packed in commercial polystyrene packages of 100 or 200 ml and heat sealed with thin aluminium foil cover. Pressure treatment of the desserts was performed at a pressure of 300 MPa, at temperatures 20 deg C or 50 deg C, in 10 min. Pressurization was conducted using high pressure food processor 1.5 1, 700 MPa developed in the High Pressure Center. Microbiological and physicochemical investigations of the pressure processed desserts were carried out directly after pressurization and after 3 months refrigerator storage. The following parameters were determined: soluble solids, (degBrix at 20 deg C), total titrable acidity (g citric acid/100 g f.u.), pH, degradation index (Di) using Fuleki method, Aspartame content and ascorbic acid content. The instrumental colour values L, a, b and dominating wave length were measured with a Minolta Chroma Meter CR200. The appearance, colour, smell, taste and consistency of the desserts were evaluated by a six person trained panel using 5-point quality scores. The products were characterized by good microbiological parameters, slightly gelatinous consistency of fruit jelly, almost natural colour, fresh fruit aroma and a taste better than that of traditional fruit desserts.
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