Effective Ways of Decreasing Acrylamide Content in Potato Crisps during Processing

Abstract

The aim of this work was to examine the effect of blanching or soaking in different acid solutions on the acrylamide content in potato crisps. Furthermore, the effects of a shorter frying time and a lower frying temperature combined with a postdrying were investigated. Soaking or blanching of potato slices in acidic solutions decreased the pH of potato juice and increased the extraction of amino acids and sugars. Potato crisps obtained after such pretreatments were characterized by lower acrylamide content. The most effective extraction of free amino acids and sugars as well as the largest decrease of acrylamide content (90%) in crisps was obtained when potato slices were soaked in acetic acid solution for 60 min at 20 degrees C. Shorter frying time followed by postdrying resulted in low-moisture potato crisps. Furthermore, the postdrying treatment gave a decreases in acrylamide content of approximately 70% when potato slices were fried at 185 degrees C and approximately 80% when potato slices were fried at 160 degrees C. Effective ways of decreasing acrylamide content in crisps production have been found. Crisps with low acrylamide content and good sensory quality can be obtained either by blanching in acetic acid as pretreatment or by a short frying followed by postdrying.

Impact of chemical pre-treatments on the acrylamide formation and sensorial quality of potato crisps

“…In addition, this blanching treat-ment led to the preparation of potato crisps with an acceptable sensory quality, such as crispiness, taste and colour. From literature, it appeared that the large product surface and the applied blanching temperatures caused a more efficient acrylamide reduction compared to soaking treatments performed at lower temperatures, due to a higher diffusion of acrylamide precursors from the potato tissue and due to a more efficient diffusion of additives into the slices (Kita et al, 2004;Pedreschi et al, 2004;. For each treatment, the acrylamide-lowering effect was determined, comparing the acrylamide content with the content in potato crisps, blanched in distilled water prior to frying (Table 1).…”

“…A number of raw material pre-treatments were investigated which could mitigate acrylamide formation. These techniques include the extraction of acrylamide precursors by soaking or blanching in water or in acidic solutions (Kita, Bråthen, Knutsen, & Wicklund, 2004;Pedreschi, Kaack, & Granby, 2004;Pedreschi, Kaack, Granby, & Troncoso, 2007).…”

“…Previously, the mitigating effect at low pH was attributed to protonation of asparagine amino groups. This would block the nucleophilic addition of asparagine with a carbonyl compound, preventing the formation of the corresponding Schiff base, a key intermediate in the Maillard reaction and in the formation of acrylamide (Kita et al, 2004;Pedreschi et al, 2004;. Also Na + or Ca 2+ were indicated to interact with asparagine to prevent the formation of acrylamide (Park et al, 2005;Lindsay & Jang, 2005;Gö kmen & Senyuva, 2007).…”

“…Acidification may moreover result in a sour product taste (Kita et al, 2004;Franke, Sell, & Reimerdes, 2005). This effect however depends upon the applied soaking or blanching treatment and the type and concentration of the acid used.…”

“…This effect however depends upon the applied soaking or blanching treatment and the type and concentration of the acid used. It was suggested that acetic acid would be a better acidulant for the pre-treatment of potato crisps compared to citric acid, due to the less appearing sourness (Kita et al, 2004). Addition of (sulphur containing) amino acids may also generate unpleasant off-flavours upon heating, which should be taken into account as well (Claeys et al, 2005).…”