Abstract: An air cleaning machine (2) separates a flowable product (28) into first and second components (60, 61) using an air leg (4) having upper and lower ends (6, 8). A vacuum source (10) is coupled to the upper end of the air leg to create a vacuum air flow (62) up through the air leg and into the vacuum chamber (12). The product, such as raisins, almonds or dates, is introduced into the air leg through a product entrance (42) and onto a downwardly sloping screen (44) by a product delivery unit (24). An air knife (50) directs a sharp stream of air (56) upwardly into the air leg and through the product as the product enters the air leg but before the product contacts the screen.