It is possible that Roos was encouraged to seek his luck in Italy following in the steps of his first master Jan de Wael's two sons, Lucas (1591–1661) and Cornelis (1592–1667).
One of his favorite themes where large scale market scenes and still lives which revealed his debt to Frans Snyders.
Roos reveals in this composition the techniques he acquired during his time in the studio of Frans Snyders for the naturalistic representation of animals, flowers, birds, insects and fruits.
In the composition he also displays his remarkable ability to render a range of textures; the downy, white plumage of the geese; the shimmering surface of the beaten copper vessel; the frosted, translucent skin of the grapes; and the gnarled, waxy surface of the pumpkin; each rendered with lifelike precision.
The bearded man looking out from the canvas over his shoulder leans over the stall, forming a diagonal echoed by the neck of the drinking goose and the extended leg of the young woman, which guides the beholder through the composition.
[8] The style of van Dyck influenced Roos' work as can be seen in the Portrait of a boy, now in the Museo del Prado.
Some of Roos' works such as The holy family (Parochial church of Moltedo, Imperia) have in the past been attributed to van Dyck.