Hi there ~
No alcohol is permitted on the weight loss phase so the answer regarding the use of Sake in your recipe for weight loss is nope, not now; later for maintenance.
Remember the serving size for red meat is 5 ounces.
Tofu is fine as a protein substitute for meat. Just remember, the portion size for Tofu is
¼ Block firm Tofu or 1 (one) 2” x 1” piece of soft Tofu
If you are using a combination of sirloin and tofu, make appropriate adjustments to the serving sizes so as to get the proper meal portion.