By Lauren Haughey Strawberries are undoubtedly a favourite snack among many Brits – though their shelf-life can be a bit of a problem. Now, one expert claims their quick trick will keep them fresher for far longer – and involves using just one surprising kitchen staple. Believe it or not, this ingredient is white vinegar which can be mixed with water to create a game-changing preservation solution. This was unveiled by cooking authors, Ariel Klein and Samantha Leffler at Real Simple, who both claimed this trick can save your fruits throughout the week and even beyond. “More often than not, per…