To solve the optimization problem described, we will use the Gurobi Python API. The goal is to maximize the objective function given, subject to various constraints related to fat and carbohydrate content from milkshakes, ravioli, and sashimi.

The objective function to maximize is: 4.36*milkshakes + 8.29*ravioli + 5.64*sashimi

Constraints:
1. Fat content constraints
   - At least 20 grams of fat from milkshakes and ravioli.
   - At least 38 grams of fat from ravioli and sashimi.
   - At least 24 grams of fat from milkshakes and sashimi.
   - At least 50 grams of fat from all three.
   - Up to 131 grams of fat from milkshakes and ravioli.
   - Up to 139 grams of fat from milkshakes and sashimi.
   - Up to 139 grams of fat from all three.

2. Carbohydrate content constraints
   - At least 122 grams of carbohydrates from milkshakes and sashimi.
   - Up to 286 grams of carbohydrates from ravioli and sashimi.
   - No more than 384 grams of carbohydrates from milkshakes and sashimi.
   - No more than 227 grams of carbohydrates from milkshakes and ravioli.
   - No more than 227 grams of carbohydrates from all three.

3. Integer constraints
   - Milkshakes, ravioli, and sashimi must be integers.

Here is the Gurobi code that captures this problem:

```python
from gurobipy import *

# Create a model
m = Model("Optimization_Problem")

# Define variables
milkshakes = m.addVar(vtype=GRB.INTEGER, name="milkshakes")
ravioli = m.addVar(vtype=GRB.INTEGER, name="ravioli")
sashimi = m.addVar(vtype=GRB.INTEGER, name="sashimi")

# Objective function
m.setObjective(4.36*milkshakes + 8.29*ravioli + 5.64*sashimi, GRB.MAXIMIZE)

# Constraints
# Fat constraints
m.addConstr(6*milkshakes + 9*ravioli >= 20, name="fat_milkshakes_ravioli")
m.addConstr(9*ravioli + sashimi >= 38, name="fat_ravioli_sashimi")
m.addConstr(6*milkshakes + sashimi >= 24, name="fat_milkshakes_sashimi")
m.addConstr(6*milkshakes + 9*ravioli + sashimi >= 50, name="fat_all")
m.addConstr(6*milkshakes + 9*ravioli <= 131, name="max_fat_milkshakes_ravioli")
m.addConstr(6*milkshakes + sashimi <= 139, name="max_fat_milkshakes_sashimi")
m.addConstr(6*milkshakes + 9*ravioli + sashimi <= 139, name="max_fat_all")

# Carbohydrate constraints
m.addConstr(9*milkshakes + 25*sashimi >= 122, name="carb_milkshakes_sashimi")
m.addConstr(23*ravioli + 25*sashimi <= 286, name="max_carb_ravioli_sashimi")
m.addConstr(9*milkshakes + 25*sashimi <= 384, name="max_carb_milkshakes_sashimi")
m.addConstr(9*milkshakes + 23*ravioli <= 227, name="max_carb_milkshakes_ravioli")
m.addConstr(9*milkshakes + 23*ravioli + 25*sashimi <= 227, name="max_carb_all")

# Optimize
m.optimize()

# Print results
for v in m.getVars():
    print(f"{v.varName}: {v.x}")

print("Objective:", m.objVal)
```