Mineral element (P [a], K [b], Ca [c], Mg [d], Na [e], Zn [f], Cu [g], Mn [h], Fe [i] and Al [j]) content of French fries after processing. LTLT low-temperature long-time (75 °C for 10 min for blanching and 160 °C for 2 min for frying), HTST high-temperature short-time (85 °C for 5 min for blanching and 180 °C for 1 min for frying). Bars with the same letter differ non-significantly (P > 0.05)