Mary Berry has criticised other cookery shows, saying that they appear not to be entirely honest with viewers.
The Great British Bake Off star, 79, is back next week for another series of the hit BBC show with fellow judge Paul Hollywood.
But Mary told Radio Times magazine that it appeared that on other culinary shows, judges were selecting certain winners to tick boxes.
She said that Bake Off had been a hit with viewers because it was honest and that the judges were left to make up their own minds and pick a winner on talent alone.
"We get no pressure from the BBC to say, 'We need someone from Scotland to win'. Nobody does that. We make the decisions," she said of Bake Off.
While not naming names, Mary added: "I often look at other cooking programmes and it doesn't seem that way."
Mary also told the magazine that her new TV career had not tempted her to consider going under the knife - adding that surgeons should be doing better things with their time.
"Botox? No, no!", she said, adding of the prospect of getting other work done: "No. I think surgeons should be saving lives rather than pulling faces about. But I do think about what I look like now, whereas before I didn't, unless I was going out to a party."
The cookery writer, who enjoyed a fashion moment when a floral jacket sold out in hours after she wore it on Bake Off, said: "At home, I don't really think about what I wear. Now people really notice, and you make more effort. Although I dress for my age... I can't wear short sleeves... because of... what do you call it? Bat wings? (bingo wings)."
She said that she makes sure that she tastes every culinary creation, whatever the consequences for her weight.
"It's terribly important to taste absolutely every bake properly. So you eat very lightly after that, for a day. Just a few salads. And then back to normal eating," she told the magazine.
The fifth series has already been filmed and is moving from BBC2 to BBC1.
Berry said of the 12 contestants: "They have watched the (previous) series. And they have concentrated on their bakes and not the peripherals, which is good.
"We can only judge them on the bake. Not on ribbons or extra sauce, or sprinkles, or things they have made around to create the atmosphere.
"The bake is the atmosphere and that is what we taste. The viewer can't, of course, taste, and the taste is very important. And we are the only two people who can describe that."
One of the people behind the scenes who does not enjoy any of the limelight is Iva Vcelak, who washes up every spatula and bowl by hand, the magazine reports, while filming is going on, because dishwashers are too noisy.
This year, in more than 160 hours, she washed around 1,000 cloths, used 80 sponges and 30 litres of washing up liquid.
