Ingredient and Meal models (Django)

models.py

class Ingredient (models.Model):
    """Describes an ingredient for meals. This ingredient contains specific
    diet and food preference information and can be attached to multiple meals."""
    name = models.CharField(max_length=255)
    franchise = models.ForeignKey(Franchise)
    diets = models.ManyToManyField(Diet, null=True, blank=True, verbose_name="special diets or food allergies")
    preferences = models.ManyToManyField(FoodPreference, null=True, blank=True)

class Meal (NutritionCapable, PricedModel, DatedModel):
    """Basic object representing a meal. NutritionCapable, PricedModel,
    and DatedModel all come from a utility class that adds fields for
    nutrition information, pricing information, and created/updated auto
    fields."""
    name = models.CharField(max_length=255)
    mc = models.ManyToManyField(MC, verbose_name="Menu Category")
    ingredients = models.ManyToManyField(Ingredient)

    def __uncode__ (self):
        return unicode(self.name)