Effects of temperature, pH, and sunlight exposure on the color stability of strawberry juice during processing and storage

摘要

The natural color of strawberries and their products easily fades or deteriorates during processing and storage. Temperature, pH, and light are common factors that affect the color stability of strawberry juice (Si). Clarified SJ was prepared from fresh fruits and diluted with purified water at a ratio of 1:3. The absorbance at 510 nm (Ab(510)) and the L* and a* values of Si under different processing or storage conditions were determined to describe the attributes and stability of juice color. SJ color was highly sensitive to thermal treatment, pH and sunlight exposure. Storage temperature also significantly affected the SJ color. SJ could achieve color stability by adjusting pH to 3.0 or below, heating at 80 degrees C or below for 20 min of less if thermal treatment is necessary, packing with opaque materials, and then storing at 2 degrees C 4 degrees C. Ab(510) positively correlated with a* under most conditions, except at different pH values. a* could be used as a direct indicator that describes Si color. (C) 2014 Elsevier Ltd. All rights reserved.