Procedure B is required for “low-lactose” or “lactose-free” samples containing high levels of monosaccharides.  Generally, these types of samples contain high levels of “free” galactose which causes a high background and reduces the dynamic range available to measure the galactose that is released from lactose in the test. To avoid this the borohydride step is used to reduce the free galactose.

Product Page (K-LACGAR)