Quality of fresh-cut apples treated at harvest with 1-MCP

Abstract

Most apples diverted to long term storage are currently treated with 1-methylcyclopropane (1-MCP) in many countries. We tested the hypothesis that 1-MCP treatment could improve the quality of fresh-cut apple slices. 'Red Chief' and 'Granny Smith' apples treated or not with 600 nl L-1 of 1-MCP at harvest were sliced after 43 and 111 d ('Red Chief') or 33 and 90 d ('Granny Smith') of storage at 0°C, 90-95% RH. The slices were treated with water or 2% ascorbic acid + 1% CaCl<inf>2</inf> (Asc+Ca), sealed in PE bags and stored at 1-2°C, 80-85% RH for three and six days. Freshly cut apple slices were used as reference control. Quality evaluation included flesh color and firmness and juice soluble solids content (SSC), acidity (TA) and total phenols. In both cultivars, slices from fruit treated with 1-MCP had similar color, SSC, TA and total phenol content and higher firmness than slices from fruit not treated with 1-MCP. In both cultivars, slice quality was similar after short or prolonged cold storage. The quality of slices after three days did not change significantly with three additional days of storage. Asc+Ca-treated slices usually had similar overall quality to freshly cut slices, but higher phenol content. Asc+Catreated slices had lighter and greener flesh color, higher total phenol content and similar firmness, SSC and TA to slices treated with water. In conclusion, 1-MCP treated apples gave harder fresh-cut product without any other quality differences compared with non-treated fruit, and treatment with 2% ascorbic acid + 1% CaCl<inf>2</inf> successfully retained the overall quality of apple slices for at least six days.