Extract and Display First Part of a Field in CloudWatch Query Results

I am trying to write a CloudWatch Log Insights query which will extract the first part of a string field up to a forward slash '/' character, which is always present in the string. Example input log lines for field named "fruit" follow: blue/berries red/apple

I need to extract the first part of the "fruit" field up to the forward slash '/' character and display it in the query results as follows, using the example input lines above: blue red

The "fruit" field is not a blob field, e.g., JSON--it's just a single string. I tried various iterations using the parse command with no luck. I also tried different ideas for using a regular expression to extract the first part of the string up to the forward slash '/' character with no luck. I searched for hints in StackOverflow too but didn't land on anything successful.

I have verified using a regular expression checker that the following will extract the first part of the string up to the forward slash character: /^.*?(?=/)/

I haven't been able to figure out how to apply the regular expression in the query correctly so that it is evaluated and displayed. Any ideas? Thank you.