Mongoose ignoring part of object unless defined as Schema.Types.Mixed

Sorry for the coffee-script.

Pulling my hair out with this one. I have a schema similar to this:

reviewSchema = Schema
  title: String
  meta: 
    author: String
    date: String
  article: String
  tags: [
    type: Schema.Types.ObjectId
    ref: "Tag"
  ]
  images: [
    type: Schema.Types.ObjectId
    ref: "Image"
  ]
  attr: 
    appearance: String
    aroma: String
    flavor: String
    from: String
    grade: String
    lineage: String
    name: String
    overall: String
    packaging: String
    pickupdate: String
    price: String
    reason: String
    story: String
    type: String
Review = mongoose.model 'Review', reviewSchema

I also have some data which I have assembled into some JSON files with corresponding data. When I go to make a new schema I look into that file and grab the JSON and create a new review object by:

thisReview = new Review json, minimize: false

If I console.log the json prior to creating 'thisReview' I see that my 'attr' key is properly filled with data but if I console.log 'thisReview' or check the database, I receive NO results for the 'attr' key of my documents. 'attr' is completely ignored.

I went as far as making sure each JSON file's JSON.attr object had each key from the schema with a "" (empty) string for those which didn't exist. The other nested objects like the meta object of the schema are populating perfectly.

Any idea what is happening?

Extra Info: When I get rid of the key/value pairs within the attr object and instead assign: attr: Schema.Types.Mixed

Then all of the data is successfully saved including the empty ("") strings.

Any help would be much appreciated.