Effect of vacuum packaging on the physico-chemical, textural, microbiological and sensory properties of dried ice cream

Dried ice cream is a dairy product that is traditionally produced in Tabriz. In the case of these traditional product has not been investigated and these research is the first scientific study on this product. The aim of this study was investigation on the effect of vacuum packaging on the qualitative features and shelf life of dried ice cream. In this process, dried ice cream was prepared by adding milk, sugar, glucose syrup and shortening, and then it was packed in two different materials (polyethylene/cardboard). The polyethylene package had been done under two different conditions (under vacuum and under normal atmosphere). Then all the samples were kept in three different temperatures (-18, and °C) for 60 days and evaluated with respect to physico-chemical, textural, microbiological and sensory properties. Moisture content and pH decreased, but acidity, free fatty acid content, peroxide value, firmness, total count and mold and yeast count increased by passing time and increasing storage temperature. In the case of sensory properties, by increasing of storage time and temperature, the related scores of color, surface quality, stiffness, mouth feeling, milky taste, rancidity taste and overall acceptability were decreased. The results showed that, although polyethylene under vacuum/cardboard package was the most suitable package regarding to pH, acidity, free fatty acid content, peroxide value, total count, mold and yeast count, but polyethylene under normal atmosphere/cardboard was the most suitable package considering the features of moisture, firmness and sensory properties. With respect to physico-chemical, textural, microbial and sensory properties, the cardboard pack (control), was the most unsuitable package. In addition, the results showed that the -18°C temperature was the most suitable storage temperature regarding to the maintaining of quality and shelf life of dried ice cream.