Most people eat a dairy meal in the morning of Shabu’oth. Let us look at a couple of reasons for this.

Shavuoth is the holiday that celebrates the giving of the Torah. The word for milk (Halav) in Gematria (Jewish numerology) has the numerical value of 40, which is the amount of days and nights in which the Torah was given.

In addition, milk is essentially blood which is red, that turns into milk which is white. So too the sins of man, through the study of the Torah, will turn into Zekhuyoth (merits) and become white as snow.

Also, through the Torah, the attribute of judgement (Middath Haddin), which is red, will be transformed into the Middath Harahamim (attribute of mercy), which is white.

(See Orah Hayyim Haggadah, Siman Taw Sad Dahl, Seder Tefillat Hagh Hashavuoth, Oth Heth)