The shock result came at the Grocer Own Label Awards, where discount chain Aldi won 16 golds - more than any other retailer.
The final decision on the herbal tea bags was made after independent research including sampling by consumers and testing by an expert panel looking at taste, texture, appearance, packaging, value for money and clarity of labelling.
And the tea bags from Harrods, which cost £5.95 for 50, were found lacking in comparison to Aldi's tea at 99p for 40 bags.
Tony Baines, managing director of buying at Aldi, told the Daily Telegraph: "We are delighted with our incredible win at these awards, and they really show how Aldi is cooking on gas when it comes to own label brands.
"Customers are looking for quality products at everyday low prices – and we're in a position to give UK shoppers just what they need."
Aldi, where profits have grown profits have grown as British shoppers increasingly search for ways to reduce their weekly shopping bills, argues that its success at the awards shows that you do not always have to pay more for quality goods.
In fact, the runner up behind Aldi was Tesco with 12 gold awards, followed by Asda with 11.
Other evidence of the success of Aldi's strategy of sourcing cheap products that offer value for money include its own label red wine Toro Loco Tempranillo 2011, priced at £3.59, beating French Grand Crus that sell for more than £30 a bottle at the recent International Wine & Spirit Competition.
You can read our story on Aldi's 18 golds at that awards ceremony by clicking here.