When Anuksha Purohit was just 10 years old, she was appalled by the sight of a Starbucks barista throwing leftover cakes and sandwiches into the garbage. 

A decade later, the memory helped inspire her to launch a startup that turns surplus bread into craft beer.

"When you go to a hotel breakfast buffet, they have a bread spread. On a plane, everybody gets a slice of bread and a bottle of water.  Bread is so common and in all the meals that we have, which is why so much of it gets thrown out," Purohit, now 23 years old, told CNBC last week on the sidelines of the Forbes 30 Under 30 Summit Asia in Singapore. 

Purohit and three university classmates came up with the idea while they were stuck studying online during the Hong Kong protests and the city's subsequent pandemic lockdown. 

"All our friends were drinking alcohol. So we decided to make alcohol instead and become the cool kids on the block," Purohit said candidly. 

They bought a 1,218 Hong Kong dollar ($156) beer brewing kit on Amazon and experimented for three weeks before making a pot of beer from leftover bread.

"The beer wasn't good when we tried it for the first time, but it made us realize this idea can work," she said.

It took the team about six months to nail down the taste before launching Breer in 2020.

Apart from a pale ale and hibiscus sour, the company also sells beers that feature flavors like egg tart and bolo bao, or pineapple bun — an homage to Hong Kong's vibrant food scene.

The company said it made HK$2.5 million in revenue in the last two years. Breer said it has already hit HK$1.8 million in sales this year and expects HK$1.2 million in profits.

The startup hasn't raised any funding, but has won about HK$6 million through startup and entrepreneur competitions without giving away equity.

Overseas expansion is not in the cards just yet, and Purohit said it would only happen if it can be done sustainably. 

"We won't ship outside of Hong Kong, but would rather work with local bakeries and breweries instead," Purohit said. "Sustainability is not about a sacrifice. You don't have to stop eating meat or you don't have to stop driving your car, you can just drink while you're drinking but choose the more sustainable option."

How it works

Every year, each person in Hong Kong wastes about 71 kilograms (156 pounds) of food.

But that presents an opportunity for companies like Breer.

Breer collects leftover bread from local restaurants, bakeries and Hong Kong-style diners known as cha chaan tengs for free. The bread is then sent to contract breweries, producing up to 4,000 to 6,000 liters of beer at least six times a year.

The amount of beer brewed per session fluctuates with demand, Purohit explained. 

"If something like Covid suddenly happens again, demand will get hit and we'll end up with so much stock. So we've decided to go with the flow and brew when people buy." 

There was even more bread waste during the pandemic when shops had a hard time estimating daily demand.

"Food estimation was askew. There would be demand for 15 kg of bread on Monday, but nobody would end up buying on Tuesday and shops will end up having more waste," recounted Purohit. She added that Breer donates excess bread to the elderly and the poor, or for use as pig and chicken feed. 

Tips for young entrepreneurs

Being a young entrepreneur comes with its own challenges, particularly difficulties in gaining trust.

When Purohit first started asking bakeries for leftover bread, she faced questions like "you just became of legal drinking age, how do you even know how to brew beer?" and "how do I believe you won't just take the bread [for yourself]?"

But after two weeks of persistence, the first bakery she approached gave her 2 kg of leftover bread on the condition that she brings back the beer made from it.

And she did just that.

Purohit shared her tips for other young entrepreneurs.

1. Be passionate about what you're doing
"If you have passion and purpose for something, the profits will flow. If there's even an ounce of you that doesn't like what you're doing, you're going to find reasons or excuses not to do it."

2. You'll never know if you don't try
"I would not be here had if I hadn't taken that one chance. You should definitely take the first step."

3. Be careful with your money
"Money is not the only investment that you need. All the money we have earned has gone back into the business."

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