Yellow tomatoes are not just unripe tomatoes.
Yellow tomatoes are actually a distinct variety of tomato that have their own unique characteristics and ripening process.
Some yellow tomatoes may start out green, although many varieties of tomatoes are yellow when fully ripe.
There are also numerous tomato varieties and some tomato varieties are bred to ripen to yellow, orange or even green in color instead of red.
Red tomatoes get their red color from lycopene, and yellow tomatoes get their yellow color from different pigments, such as carotenoids.
Yellow tomatoes also often have a milder taste and are less acidic, and sometimes are sweeter in flavor than red tomatoes.
A tomatoes color change also indicates ripening, although the final color of the tomato can vary depending on the variety.
And some tomatoes may show a blush of yellow color or light pink color before turning fully red.
When it comes to canning of tomatoes, ripe tomatoes of any color including yellow are safe and are equivalent in terms of their acidity.
Yellow tomatoes are just a different type of tomato that have their own unique qualities and are also just as delicious and safe to eat when they are fully ripe.