Schema.pre('save', not saving new columns to table (Mongoose)

I typed this in as the example said to but the new columns are still coming back blank. Odds are it is something small that I’m missing. Any help would be great!

var mongoose = require('mongoose');

require('./User');

var Schema = mongoose.Schema;

var IngredientSchema = new Schema({ 

User: {

    type: Schema.Types.ObjectId,

    ref: 'User'

},

Ingredient: {

    type: String

},

Type: {

    type: String

},

Amount: {

    type: Number

},

tbs: {

    type: Number

},

tsp: {

    type: Number

},

floz: {

    type: Number

}

});

IngredientSchema.pre('save', function(next){

    if(this.Type === 'tbs'){

        this.tbs = 1*this.Amount;

        this.tsp = this.Amount/3;

        this.floz = this.Amount*2;

    }

    if(this.Type === 'tsp'){

        this.tbs = this.Amount*3;

        this.tsp = this.Amount*1;

        this.floz = this.Amount*6;

    }

    if(this.Type === 'floz'){

        this.floz = this.Amount*1;

        this.tbs = this.Amount/2;

        this.tsp = this.Amount/6;

    }

    next();

})

module.exports = Ingredient = mongoose.model('Ingredient', IngredientSchema);