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Quality of stored strawberry puree produced in an oxygen-reduced environment
Abstract
The strawberry fruit Fragaria ananassa is a universally desirable fruit. Strawberries are consumed fresh, or processed and have become increasingly popular ingredients in popular foods and drinks. Numerous quality problems are encountered in processed and stored strawberry products. Some of these problems include color changes, loss of texture and changes in the sensory profile, all of which reduce consumer appeal of the product. This research determined the effect of eliminating oxygen during heat processing (85$\sp\circ$C for 20 sec.) and the role of light during storage (3 months) on the physical (a, b and L Hunter Lab Color values and viscosity), chemical (pH. titsatable acidity, polyphenol oxidase activity, total anthocyanins and volatile analysis), and sensory quality (odor, color, texture and flavor) of the stored puree. The elimination of air during processing had a positive effect on color as reflected in Hunter "a" value, hue angle and the saturation index. In the first two months of storage, sensory analysis and instrumental analysis did not show differences between O (control processed in conventional environment (air)) or N (nitrogen treated) samples except in color. But during the third month, the sensory panelists found the O treated samples to be unacceptable in overall appearance and odor. During the third month of storage, the sensory values for all sensory descriptors were higher for NL (nitrogen treated stored under fluorescent light) than NNL (nitrogen treated stored in the dark). This suggests that with long storage, light increased the rate of some reactions (or at least kept them constant) in strawberry purees. These reactions either affected the quality positively (increasing the sensory scores for strawberry, odor and strawberry flavor) or affected the quality negatively by increasing brown pigment formation (sensory color) and increasing acid flavor bitter flavor, and off-flavor. Other chemical analysis did not reveal any significant differences between the two treatments or the sub-treatments.
Subject Area
Food science
Recommended Citation
Al-Maiman, Salah Abdulaziz, "Quality of stored strawberry puree produced in an oxygen-reduced environment" (1997). ETD collection for University of Nebraska-Lincoln. AAI9812344.
https://digitalcommons.unl.edu/dissertations/AAI9812344