Refrigerated potato strips production

The effects of processing conditions ---blanching time, ascorbic acid (AA) and calcium chloride (CaCl2) concentrations and potato variety--- on color and textural quality of refrigerated potato strips were investigated. The highest peak force was determined in potato fries blanched at low temperature (60°C) for 30 min and then blanched at high temperature (∼98°C) for 5 min. However, there was no significant difference in peak force of potato fries blanched at low temperature for 30 or 20 min followed by high temperature blanching for 10 or 5 min. Changes in blanching time did not affect the lightness of potato fries. Increasing CaCl2 concentration caused a significant increase in peak force of potato strips. Ascorbic acid did not affect color. The highest iii peak force was obtained in potato fries prepared from the Russet Burbank variety. The results indicate that blanching the Russet Burbank variety of potato strips at low temperature (60°C) in 0.5% CaCl2 solution for 20 or 30 min followed by blanching at high temperature (∼98°C) in boiling water for 5 or 10 min was effective in potato strips processing to improve color and textural quality. However, optimal quality varies based on customer preferences.;In this part of the study, the effect of low (60°C) and high (∼98°C) temperature blanching time and storage time on microbial, color and textural quality of near-aseptically packaged refrigerated potato strips were examined. Microbial spoilage was observed for all treatments which received a high temperature blanch of only one minute. No microbial growth was observed within 28 days of refrigerated storage for strips treated for either 10- or 20-min in low temperature blanch followed by 5- or 10-min in high temperature blanch. Near-aseptically packaged refrigerated potato fries were lighter in color (P < 0.05) than unprocessed fries (neither blanched nor near-aseptically packaged) and less color difference (P < 0.05) was observed in near-aseptic potato fries compared to unprocessed fries. Near-aseptic potato fries were higher in peak force (P < 0.05) compared to unprocessed fries. No significant changes were observed in the quality of near-aseptically packaged refrigerated potato strips during 28 days of storage at 7°C.;Gaseous ozone, a strong antimicrobial agent, was studied as an in-package treatment of blanched potato strips to extend shelf-life. Potato strips were subjected to a batch ozone treatment for 20 s or a continuous ozone treatment for 5, 15 or 30 min by injecting ozone gas into the package. Microbial growth was observed the following day for bags with no ozone treatments. Continuous ozone treatment was effective in extending shelf-life of refrigerated potato strips compared to batch ozone treatment. No microbial growth was observed in 30- and 15-min continuous ozone treated strips after 28 and 21 days storage, respectively. There was no significant difference between the color of blanched strips and ozone treated blanched strips.;Finally, using the best treatments for the earlier experiments, the effects of near-aseptic packaging and in-package chemical treatments with gaseous ozone, sodium metabisulfite (SM) solution and FIT Fruit and Vegetable Wash(TM) solution on 2-step blanched potato strips were investigated. There was no microbial growth on any of the potato strips during 28 days of refrigerated storage. In SM treated strips, lighter color (P < 0.05) and less color difference (P < 0.05) were observed after frying compared to other treatments. Near-aseptic packaging was found to be an effective non-chemical alternative because there was no significant difference in before-frying color, textural quality and oil content compared to SM treatment which is currently the industry practice. FIT was found to be the most effective chemical treatment because the FIT significantly increased after-frying peak force of fries. Gaseous ozone treatment significantly decreased the color quality of potato strips. There was no significant difference in the oil content of near-aseptically packaged potato fries, in package chemically treated potato fries and unprocessed fries.;Overall, the research results indicate that two-step blanching is necessary in improving color and textural quality of potato strips. Near-aseptic packaging as a non-chemical treatment and in-package FIT treatment are the better alternatives for blanched potato strips to extend shelf-life and maintain quality. (Abstract shortened by UMI.)...