I am going to detect the 10g fruit and the threshold of my pressure sensor is 100g, does anyone know which sensor can use to detect 10g fruit.
Which sensor do you have ? A load cell for 100kg ?
A load cell (it has strain gauges inside) can be accurate and they come in all kind of sizes.
If you buy a cheap pocket scale of 10 dollars/euros, and if you open it up, then you probably find a load cell. You might even use that load cell to connect to a Arduino, with the proper chip to read the strain gauges.
Now that I think about it, I'm 100% sure that those pockets scales use a load cell.
You can pick up one of these cheaply
https://uk.farnell.com/duratool/d03407/weighing-scale-pocket-0-01g-200g/dp/3573554
Less than £4, might be worth a hack.