Shelf Life of Sliced Raw Potatoes of Various Cultivar Varieties—Substitution of Bisulfites

Abstract

The effects of potato variety (Van Gogh, Bintje and Fambo), washing with browning prevention chemicals in place of sodium bisulfite, percentages of CO2, O2, and N2 in the package headspace, and storage time (1, 4, and 7 days) on the sensory and microbiological quality of potato slices were examined. Citric acid and ascorbic acid (at 0.1% each and at 0.5% each) were used as browning prevention chemicals. In the packaging atmosphere the percentage of N2 was 75 or 80%, the percentage of O2 was 5 or 0%, and the percentage of CO2 was 20% at the beginning of storage. Packed potato slices were stored in the dark at 5 degrees C. Darkening was the most important factor limiting the sensory quality of raw potato slices. Darkening occurred quickly with Fambo slices; it seems that Fambo is not a suitable potato variety if slices are to be stored. Water-washed and cooked Van Gogh slices were still acceptable for retailing after a storage period of 7 days. After 7 days of storage the best sensory quality of both raw and cooked Bintje slices was obtained with washing solutions containing 0.1 to 0.5% citric and ascorbic acids and with the gas mixture containing 20% CO2 and 80% N2. The number of microorganisms was higher in samples stored in the atmosphere containing 5% O2 than samples stored in the atmosphere containing 0% O2. Washing of potato slices with browning prevention chemicals decreased the number of microorganisms compared to potato slices not washed or potato slices washed with water after 7 days of storage.

Reassessment of treatments to retard browning of fresh-cut Russet potato with emphasis on controlled atmospheres and low concentrations of bisulphite

“…This synergistic combination of AA + CIA with CA has been reported for various fresh-cut products (Laurila et al, 1998a;Gorny et al, 2002;He & Luo, 2007), but Jiang et al (2004) found that CIA alone retarded discolouration of cut water chestnut. SB was much better than AA + CIA as an anti-browning agent, a result consistent with many other reports (Gunes & Lee, 1997;Laurila et al, 1998b;Beltra´n et al, 2005). AA or ⁄ and CIA have been found effective to inhibit browning on cut potato in other studies (Ahvenainen et al, 1998;Rocha et al, 1998;Jiang et al, 2004;Limbo & Piergiovanni, 2006, but were ineffective in the present study on high browning potatoes.…”

“…An O 2 concentration as low as 0.3% would likely induce anaerobic metabolism (Mateos et al, 1993;Gorny et al, 2002;Ango´s et al, 2007). Laurila et al (1998b) found that modified atmospheres alone provided some benefit but did not completely maintain visual appearance of cut potato slices. The 3% O 2 + 12% CO 2 atmosphere was used in further testing because of the benefits noted and because it is an atmosphere that can be easily achieved with currently available plastic film packaging for fresh-cut products.…”

“…Citric acid (CIA), another widely used anti-browning agent, has a dual inhibitory effect by lowering the pH and chelating the copper at the active site of PPO (Martinez & Whitaker, 1995). AA is often applied in combination with CIA for improved efficacy (Laurila et al, 1998b;Limbo & Piergiovanni, 2006Rocculi et al, 2007).…”

“…Although sulphites can cause allergic reactions in some people, they are allowed at low concentrations in potato products as most of the sulphite is lost during cooking (FDA, 2010;FMI, 2010). Because sulphites are low cost and very effective, it has been a challenge to find efficacious anti-browning replacements (Sapers et al, 1990;Gunes & Lee, 1997;Ahvenainen et al, 1998;Laurila et al, 1998b).…”

“…Chemicals containing SH-groups including sulphites are employed to prevent browning in vegetables such as potatoes (Laurila et al, 1998b). Sulphites retard microbial activity and inhibit enzymatic (competitive inhibitor of PPO) and nonenzymatic browning reactions (Beltra´n et al, 2005).…”