When Del Currie decided to give up single-use plastic he had one "naughty secret" - he couldn't quit his love of crisps.
 
He says his environmentally-minded daughter was not pleased when she found out that he was cheating.
 
She suggested that if he was serious about making a difference then he should launch his own crisp company, one that doesn't sell them in plastic packets.
"So I replied, 'Alright then, I will,'" says Mr Currie, who previously worked in app development. "It wasn't so much a choice to create packet-free crisps, there just wasn't anyone doing anything good, so I decided to jump into it."
 
True to his word, in March this year he launched Spudos, which now supplies crisps to more than 65 so-called "zero-waste shops" across the UK and Republic of Ireland. These are stores that aim to eliminate packaging, and instead encourage customers to turn up with their own containers, which they fill from dispensers.
 
Purchasers of Spudos then flavour and season the crisps in the store, with one of the company's "Spud Dust" shakers. These cylinder-shaped shakers are made of plastic, but are designed to be sent back to the firm's base in East London for refilling.
 
For internet orders from customers both across the UK and overseas, Spudos packages its crisps and flavourings in packets made from a natural material called cellulose, which is derived from wood pulp. These decompose in about 45 days.
 
Additionally, people can order a refillable tub which, although made of plastic, is designed to be used again and again.
 
While most of us don't give crisps, or as they say in North America, potato chips, much thought as we crunch on them, their manufacture and sale is a huge industry.
Worldwide sales in 2021 totalled $32.2bn (£26.6bn), according to one study, and in the UK alone it is widely reported that six billion packets of crisps are consumed every year. Meanwhile, data for the US says Americans typically eat 1.85 billion pounds (839 million kg) of potato chips per year.
 
A problem with this consumption is the packaging - most crisps continue to be sold in single-use, non-recyclable plastic packets. These can take decades to finally decompose.
 
The biggest names in the crisps sector say they will need additional time to switch to more environmentally-friendly packaging.
 
In the UK, the best-selling brand by far is Walkers, which makes 14 million packs of crisps per day. In 2018, the fact that its packets are not recyclable made the headlines when environmental campaigners started to post the packets back to the company.
 
Walkers' owner, US giant PepsiCo, says it will move to the use of recycled or renewable plastics by 2030.
 
In the meantime, it is smaller crisps firms who are leading the way in terms of more eco-friendly packaging, such as Canadian business Humble Potato Chips. It was launched earlier this year by Alicia Lahey and her husband Jeff.
 
Their compostable crisp packets are also made mostly from cellulose, and are certified plastic-free. They are said to have a comparable shelf life to plastic bags, and are now on sale in both Canada and the US.
 
"We started Humble Potato Chips for our son Wilder," says Ms Lahey. "When he was born we began to hope for a future that wasn't just our own.
 
"Our goal is to inform people that we don't have to rely solely on plastic for food packaging, and we can all help to kick micro-plastics from our food system, human bodies, oceans and soil."
 
Back in the UK, Herefordshire-based farmers Sean Mason and Mark Green launched sustainable crisps brand Two Farmers in 2018. They were inspired to seek biodegradable packaging after being fed up with finding empty plastic crisp packets on their farms.
The duo ultimately spent four years trying to find suitable packets that would enable them bring the crisps to market. "Eventually we visited a packaging show, and came across sustainable cellulose film, and combined it with plant-based biodegradable ink and glue," says Mr Mason.
 
"They [the packaging firm in question] had never made it into crisp packets before, and it took two and a half years to develop."
 
In the end the cost of the finished packaging had quadrupled in predicted price. "[But] we are trying to give people the option if they want to spend a bit more on something that's more environmentally friendly. As we scale up, costs will come down."
 
Two Farmers crisps are now sold on the Eurostar trains between London and Paris and Brussels, and Mr Mason says they are "in talks to launch in several European countries in early 2023".
 
But why are plastic crisp packets not typically recyclable? Shelie Miller, professor in sustainable systems at the University of Michigan, says it is because "most are not made solely out of plastic, but thin layers of metal and plastic".
 
"The mixture of both metal and plastic pose a real challenge to recycling systems, which need to separate individual materials for recycling. Not only are the packages a mixture of materials, but the separating two different materials on such a thin package is incredibly challenging from a technical perspective, and infeasible economically."
 
But Prof Miller also cautions that there are some issues with biodegradable packaging, such as people wrongly putting it out with their recycling, where it could act as a contaminant. This could mean that affected items can no longer be recycled.