Here's the Gurobi code to solve the optimization problem. The code defines the variables, objective function, and constraints based on the provided description. It then optimizes the model and prints the results, including the optimal objective value and the values of the decision variables.

```python
from gurobipy import Model, GRB

# Create a new model
model = Model("vitamin_optimization")

# Create variables
b1 = model.addVar(lb=0, vtype=GRB.CONTINUOUS, name="vitamin_b1")
b7 = model.addVar(lb=0, vtype=GRB.CONTINUOUS, name="vitamin_b7")
fat = model.addVar(lb=0, vtype=GRB.CONTINUOUS, name="fat")
b12 = model.addVar(lb=0, vtype=GRB.CONTINUOUS, name="vitamin_b12")
zinc = model.addVar(lb=0, vtype=GRB.CONTINUOUS, name="zinc")

# Set objective function
model.setObjective(9 * b1 + 1 * b7 + 7 * fat + 8 * b12 + 1 * zinc, GRB.MAXIMIZE)

# Add constraints
model.addConstr(25 * fat + 24 * zinc >= 45, "c1")
model.addConstr(3 * b1 + 2 * b7 + 24 * zinc >= 51, "c2")
model.addConstr(25 * fat + 16 * b12 + 24 * zinc >= 51, "c3")
model.addConstr(3 * b1 + 16 * b12 + 24 * zinc >= 51, "c4")
model.addConstr(2 * b7 + 25 * fat + 16 * b12 >= 51, "c5")
model.addConstr(3 * b1 + 25 * fat + 24 * zinc >= 51, "c6")
model.addConstr(3 * b1 + 25 * fat + 16 * b12 >= 51, "c7")
model.addConstr(3 * b1 + 2 * b7 + 24 * zinc >= 43, "c8")
model.addConstr(25 * fat + 16 * b12 + 24 * zinc >= 43, "c9")
model.addConstr(3 * b1 + 16 * b12 + 24 * zinc >= 43, "c10")
model.addConstr(2 * b7 + 25 * fat + 16 * b12 >= 43, "c11")
model.addConstr(3 * b1 + 25 * fat + 24 * zinc >= 43, "c12")
model.addConstr(3 * b1 + 25 * fat + 16 * b12 >= 43, "c13")
model.addConstr(3 * b1 + 2 * b7 + 24 * zinc >= 50, "c14")
model.addConstr(25 * fat + 16 * b12 + 24 * zinc >= 50, "c15")
model.addConstr(3 * b1 + 16 * b12 + 24 * zinc >= 50, "c16")
model.addConstr(2 * b7 + 25 * fat + 16 * b12 >= 50, "c17")
model.addConstr(3 * b1 + 25 * fat + 24 * zinc >= 50, "c18")
model.addConstr(3 * b1 + 25 * fat + 16 * b12 >= 50, "c19")
model.addConstr(3 * b1 + 2 * b7 + 24 * zinc >= 56, "c20")
model.addConstr(25 * fat + 16 * b12 + 24 * zinc >= 56, "c21")
model.addConstr(3 * b1 + 16 * b12 + 24 * zinc >= 56, "c22")
model.addConstr(2 * b7 + 25 * fat + 16 * b12 >= 56, "c23")
model.addConstr(3 * b1 + 25 * fat + 24 * zinc >= 56, "c24")
model.addConstr(3 * b1 + 25 * fat + 16 * b12 >= 56, "c25")
model.addConstr(3 * b1 + 2 * b7 + 24 * zinc >= 67, "c26")
model.addConstr(25 * fat + 16 * b12 + 24 * zinc >= 67, "c27")
model.addConstr(3 * b1 + 16 * b12 + 24 * zinc >= 67, "c28")
model.addConstr(2 * b7 + 25 * fat + 16 * b12 >= 67, "c29")
model.addConstr(3 * b1 + 25 * fat + 24 * zinc >= 67, "c30")
model.addConstr(3 * b1 + 25 * fat + 16 * b12 >= 67, "c31")
model.addConstr(3 * b1 + 2 * b7 + 24 * zinc >= 49, "c32")
model.addConstr(25 * fat + 16 * b12 + 24 * zinc >= 49, "c33")
model.addConstr(3 * b1 + 16 * b12 + 24 * zinc >= 49, "c34")
model.addConstr(2 * b7 + 25 * fat + 16 * b12 >= 49, "c35")
model.addConstr(3 * b1 + 25 * fat + 24 * zinc >= 49, "c36")
model.addConstr(3 * b1 + 25 * fat + 16 * b12 >= 49, "c37")
model.addConstr(3 * b1 + 16 * b12 <= 328, "c38")
model.addConstr(2 * b7 + 16 * b12 <= 167, "c39")
model.addConstr(3 * b1 + 2 * b7 <= 328, "c40")
model.addConstr(2 * b7 + 25 * fat <= 341, "c41")
model.addConstr(3 * b1 + 25 * fat <= 342, "c42")
model.addConstr(3 * b1 + 2 * b7 + 25 * fat + 16 * b12 + 24 * zinc <= 342, "c43")


# Optimize model
model.optimize()

# Print results
if model.status == GRB.OPTIMAL:
    print(f"Optimal objective value: {model.objVal}")
    for v in model.getVars():
        print(f"{v.varName}: {v.x}")
elif model.status == GRB.INFEASIBLE:
    print("Model is infeasible.")
else:
    print(f"Optimization ended with status {model.status}")

```
