When it comes to our favourite fruit and veg, be they bananas or potatoes or plums, a very small number of varieties tend to dominate the supermarket shelves.
These varieties have been carefully bred and selected to meet the imperatives of shelf stability, appearance, customer preference, and maximum yield. That sometimes comes at the expense of smell and taste and colour and, some claim, it can affect a fruit or vegetable's nutritional composition too.
Mark Christensen of the Heritage Food Crops Research Trust in Whanganui told This Way Up's Simon Morton, "There's been a great deal of breeding and manipulation of our food and unfortunately it's been done predominantly for commercial reasons. In doing that the beneficial compounds have either been bred down or bred out of the varieties."
So Mr Christensen is trying to take our fruit and veggies back to the future to make them better for us. He's rediscovering healthier fruit and vegetables among the heirloom varieties that have been forgotten by the modern food production system.
He's done it already with apples and a variety called Monty's Surprise, now he's onto orange tomatoes that can confer health benefits when they're eaten raw and not just when they're cooked. Next he's set his sights on the carrot!
This isn't a money making venture either; Mr Christensen and the Trust give the seeds away to home gardeners across the country.
Gallery: Mark Christensen's heirloom garden