Try using activated charcoal odor absorber instead of baking soda. Or, at least use it for something besides freshening the refrigerator. I found that the best way to really keep odors out of the fridge or freezer is with an activated charcoal odor absorber.
The one I got is made with a bamboo bag that goes around the odor absorber. It does not mask odors. It eliminates them without adding any fragrance to the fridge. I recommend bamboo because it is sustainable and allergen-free. It is safe for foods to be around and will last for about two years. What you have to do to take care of the bags is place them in sunlight for an hour once every few months. This rejuvenates the charcoal. When the charcoal gets reactivated, it works harder to absorb odors and even excess moisture in the refrigerator.
I have two of these bags. I use one in the fridge and one in the freezer. I’d look for one that is made with bamboo because it is a renewable resource and that makes me feel good about the product. Most times, you can buy these bags online in packets of two.