|Zhu, Yi - UC DAVIS, DAVIS, CA|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: December 1, 2004
Publication Date: July 16, 2005
Citation: Zhu, Y., Pan, Z. 2005. Effects of dipping treatments on color stabilization and quality of apple cubes. Meeting Abstract No. 96-3. IFT Annual Meeting. July 2005. New Orleans, LA. Interpretive Summary: Dipping is an important and necessary pretreatment in processes of fruits and vegetables. It is used to prevent enzymatic browning caused by polyphenol oxidase. This study investigated the effectiveness of various dipping solutions on the color stability of apple cubes. The research results indicted that using ascorbic acid and citric acid as pretreatments were important for improving the color stability.
Technical Abstract: Dipping is an important and necessary pretreatment in processes of fruits and vegetables. It is used to prevent enzymatic browning caused by polyphenol oxidase. Several chemicals including ascorbic acid (AA), citric acid (CA) and calcium chloride (CC) have shown the capability of stabilizing color of cut apples during long time storage. However, effect of dipping solution concentration and time on the color stabilization has not been well studied. The objective of this research was to investigate the effects of the dipping solution concentration and dipping time on the color, texture and solid loss of fresh cut and infrared blanched apple cubes. Fresh cut 12.8 mm apple cubes were dipped in the solutions containing AA, CA and CC at different concentrations from 0.1% to 1.5% for various times from 0 to 10 min. The solid losses of the samples were measured during dipping. Some of the dipped samples were further blanched with infrared heating. The color and texture of the dipped samples with and without blanching were determined after the samples were exposed in ambient air for different times from 0 to 100 min. The results showed that CA alone had almost no effect on preventing browning of the apple cubes. The combination of any two chemicals among the three chemicals tested could effectively reduce the enzymatic browning rate. No further color change was observed after IR blanching when apple cubes were dipped in 0.5%AA+0.5%CC solution for 5 min. Apple cubes treated with the combination of CA and AA showed poorest texture after IR blanching. The amount of solid loss was directly related to the dipping time. The research suggests that dipping with AA and CC solution is a very important pretreatment in apple blanching process to stabilize the color and improve the texture of blanched products.