One of the drivers behind the technologies is the question of how the world's growing population can be fed.
Mrs Marsh doesn't think the "alternative proteins" will end up being high-priced premium products, or replace meat.
"Eating is also an emotional thing. I'm still going to enjoy my nice juicy steak on a Saturday night if I'm out for dinner," she said.
New Zealand may be best to continue supplying high priced and high quality proteins, produced in traditional ways.
"We are going to have to be picky about what food we grow and who we are selling it to and how. We will be going for a premium."
On the other hand she said young people like to try new foods, and people are tending to eat less meat. The alternative proteins would have a smaller environmental footprint than traditional production and animals would not be killed or mistreated.
Some consumers will like that, while others will be suspicious about the technological side.
The first lab-grown hamburger was eaten in London in 2013. To make it, cattle cells were removed by biopsy and grown in a solution, then clumped together.
Some people have been reluctant to try the new food.
Experiments showed they tended to feel better about eating such meat if they knew the animal in question. It could even be a pet, living a happy life, with just a few cells removed and grown.
In the United States a few restaurants are selling the "impossible burger". It's made out of soy, wheat, coconut oil and potatoes, with an ingredient called haem that provides iron and is made by genetically engineered yeast.
"It can replace an ordinary burger and apparently it tastes quite good - not like a typical vegan patty - it tastes a lot like meat," Mrs Marsh said.
Its Silicon Valley researchers say they can also make chicken, pork, fish and yogurt.
And Silicon Valley has made a synthetic milk, which is not yet commercially available.
Federated Farmers' dairy chairman Andrew Hoggard said that could become a threat to New Zealand's dairy industry.
But he predicts there will still be people who want to buy natural milk, and said cheap synthetic milk might make some production overseas uneconomic, which would favour New Zealand farmers.