Thursday, June 24, 2010

Please, no substitutions. Mostly.

"Please, no substitutions."  How many times have you seen those words discreetly printed at the bottom of a restaurant's menu?  The main dishes and the sides that come with them are prescribed by the restaurant, and they're loathe to deviate from those set combinations.  (Thankfully, I've found that most restaurants with "no substitutions" policies are quite accommodating when you bring up the topic of food allergies...)

Of course, at home in the kitchen we all make substitutions with recipes all the time.  Maybe you don't have the exact ingredient called for in a recipe, so you use something else in its place.  Maybe you modify a recipe to suit your own preferences, taking out a food you don't like, and adding one that you do.  Maybe you sub a recipe's ingredients in order to make it fit with your personal dietary ethics (as is often the case with vegetarians and vegans), or to improve its nutritional profile.  Maybe you simply want to modify a recipe in order to "make it your own."  Or maybe you take a "standard" recipe, and substitute ingredients in order to make it fit with dietary restrictions (such as gluten, dairy, peanuts, whatever...).  These are all good and valid reasons to make substitutions in a dish.

When making substitutions, however, it's important to have realistic expectations.  Not all substitutions are created equal.  Depending on what type of food you're making, and what ingredient(s) you're substituting, it can be a non-trivial thing.  This is especially true in baking.  Sub-ing ingredients in and out of a baking recipe is not nearly as simple and straightforward as swapping a glass of soy milk for a glass of cow's milk.  Baking is a science, genuinely.  Every ingredient is in a recipe for a reason.  It has certain properties and performs certain functions, and oftentimes, substitutes just don't get it done.  (At least, not easily and not without other major modifications.)

Here's a case in point: Some time after posting my finalized recipe for gluten-free sandwich bread, I received a personal email from a reader to this effect - "I tried your recipe and it didn't work for me.  Oh, and by the way, I substituted soy milk for cow's milk, Earth Balance for real butter, and Ener-G Egg Replacer for the egg whites."  Well, no wonder problems arose!  In truth, this person didn't make my recipe, and my recipe didn't fail.  They made a heavily modified version of the recipe, with significant and crucial substitutions.

Consider the eggs.  I used eggs whites in my bread recipe for a very specific reason.  Egg whites are comprised almost exclusively of protein.  In particular, they contain a brand of proteins known as albumins, which are what enable you to whip egg whites into stiff peaks.  In baking, those same albumin proteins - in concert with xanthan gum - can help to more closely mimic gluten, resulting in the sandwich bread I was so proud of.  Now, consider Ener-G Egg Replacer.  It is made mostly from potato starch and tapioca starch.  Nutritionally, it is almost exclusively carbohydrate.  In other words, although it is called "egg replacer," when it comes to baking and the role of eggs in sandwich bread, Ener-G Egg Replacer does nothing of the sort.  It is all carbs.  Egg whites are all protein.  The egg replacer contains none of the desirable albumin proteins.

I'm not saying you shouldn't bake without eggs, or shouldn't use "replacement" products as you see fit, or shouldn't substitute in recipes.  Quite the contrary.  But when you do, first take a step back and ask yourself some important questions: Why is an ingredient in the recipe?  What role does it play?  When it comes to gluten, we tend to be more familiar with the answer - gluten is what makes dough "doughy."  It makes dough elastic and stretchy, and enables it to retain gas bubbles when dough rises and bakes.

When it comes to dairy, egg and other substitutions, the waters may get a little murkier.  Even if the answer isn't obvious, it's helpful to think about these sorts of things, and to adjust expectations accordingly.  And remember: if a recipe doesn't work out quite according to plan after you've made some substitutions, don't be discouraged.  There's almost certainly a solution out there, even if you haven't found it or figured it out just yet.

- Pete

6 comments:

Kim Nixon said...

Sometimes it is not a choice. I cannot use eggs. I cannot digest eggs. I need a way to make bread and bake that fits my restrictions. I am gluten free, dairy/casien, egg, corn, oat, and can only tolerate small amounts of soy. As ou can imagine this makes adaptation of recipes difficult at best. Do you have suggestions for those of us needing a better egg replacer?

peterbronski said...

Hi Kim... I absolutely understand that's it often not a choice. That's why, in the second paragraph of my post, I talk about making substitutions for the sake of dietary restrictions, such as gluten, dairy, egg, corn, etc. Don't get me wrong - in certain applications, Ener-G Egg Replacer is just fine. But when what you need is the protein from egg whites, it's insufficient. Most of the egg substitutions (Ener-G, applesauce, cornstarch mixed in water, banana, an oil-water-baking powder blend, etc.) are all carb heavy, and light on the protein. So far, I think the best analog is flax gel, made from 1 tbsp flax meal to 3 tbsp water. However, I have to test using flax gel in recipes more before I can recommend it with confidence.

Cheers, Pete

Stephanie said...

I agree that learning about WHAT you're substituting out is so important when adapting a recipe. I get all sorts of creative in the kitchen, and feel much more confident now that I know what purpose each of my ingredients serves in the dish. Breads can be especially tricky though!

peterbronski said...

Hi Stephanie... Yeah, I agree. Substitutions in bread are some of the trickiest. Have you tackled any of the hikes on your list recently?

Cheers, Pete

theMom said...

Your post brings up a question I've been wondering for awhile now. What is the function of the small amount of potato flour in your artisan blend?

I have so many other flours around, as I'm sure you understand, that the few times I've found myself needing it didn't justify the extra shelf space it took.

Is it for moisture and what I'll call clinginess, which is different somewhat to what I think of as elasticity? I often use potato water (the drained liquid from boiled potatoes) to replace all or some of the liquid in a recipe. I don't know anything about the science of potato water, but it seems to give breads the quality of maintaining their moisture longer. It deters them from becoming dry and crumbly as quickly, hence the moist/clingy descriptor. Is this the quality your potato flour adds? If so, perhaps combined with dry milk powder, potato water could replace the small amount of potato flour.

I've not used glutinous rice (sweet rice) often, because I have to drive 75 miles to be in a large enough city to stock it. But I do keep it around when I can. Does it lend the same qualities as potato flour? Again, I don't know the science, but I'm trying to remember what it seemed to accomplish the times I've used it.

You guys are so good about the details that make cooking outside the ordinary much easier. Thanks.

Mary

peterbronski said...

Hi Mary... The potato flour in our blend is for texture. When we were in the final days of tweaking the blend, we kept all factors constant and adjusted only the ratio of potato starch and potato flour to get the best texture in baked goods.

Unlike potato starch, which is just the isolated starch from potatoes, potato flour is made from the whole potato, so it also has a small amount of protein, and a coarser, less dense particle size that's good for texture.

I'll have to check how the texture of dry milker powder compares. It has similar carbs, but more protein. In combo with a little potato water, it might work, but I can't say for sure. One of these weeks I'll try and do a test batch!

Cheers, Pete