THE INFLUENCE OF CHILLING STORAGE ON COLOR, pH AND ACIDITY OF FRUIT SMOOTHIE BEVERAGES

Recently, for increasing smoothies shelf life, food industries used thermal processing, which has been shown in some studies to affect the sensorial and physic-chemical properties of these products. Color, flavor, texture and physico-chemical properties of food products have an important role in correlation with taste, sensory perception and consumer acceptance. These are critical quality attributes affecting the acceptability of fruits, fresh or processed, thus being of major concern in product design. The aim of this study is to observe the influence of chilling storage on color, pH and acidity of some products based on mixtures of pressed and squeezed fruits without adding preservatives or stabilizers. For this purpose, some mixtures of several pressed fruit like apples-pears, peaches-mango and sour cherry ?bananas were purchased from a local market. These mixtures were stored in climate chamber at 50 C, the color, pH and acidity being analyzed throughout the 27 days chilling storage period. During chilling storage the lightness index, L, yellowness index, b and the redness index, a, were measured and it was observed color changes for all of fruit smoothie samples. pH and acidity values, showed that the fruit smoothie samples registered insignificant changes in this comparative study between the same samples after different chilling storage period.