THE GOCHISO GOURMET: Fermentation 101


Tomato Sourdough Focaccia. photo by Ryan Tatsumoto

columnist-logo_ryantatsumoto_FINALWhether we think about it or not, we’ve all experienced fermentation, whether it’s via imbibing my favorite breakfast, lunch or dinner grape juice-based beverage or simply pushed a little harder in the gym and experienced that muscle burn the next day. In a nutshell, fermentation simply is the biochemical process in which sugars are converted into acids, alcohol or gas. In culinary speak, fermentation is responsible for much more than your favorite malted alcoholic beverage or bottle of vino.

Human Fermentation
Homolactic fermentation occurs in your muscle tissue when oxygen isn’t being delivered at a fast enough pace for actively metabolizing muscle tissue. Like when you’re pushing your cardio to the point that you feel like your lungs are about to exit your mouth, or when you try to speak to your cardio buddies next to you but simply drool when you open your mouth. Under pure aerobic (with oxygen) conditions when you can actually speak to your gym buddies, one molecule of glucose produce two molecules of pyruvic acid, which then enters the Krebs Cycle (remember, biochemistry?) which then produces a gaggle of Nicotinamide adenine dinucleotide  molecules for energy. However, under anaerobic (devoid of oxygen) conditions, that one glucose molecule creates two molecules of lactic acid and actually uses energy leaving you with that lactic acid muscle burn.

Microbial Fermentation
Microbial fermentation in the culinary world occurs primarily via yeast, which produces alcohol and carbon dioxide under anaerobic conditions or lactic acid and carbon dioxide under aerobic conditions or via lactobacilli or other bacteria which produces lactic acid.

I’m sure everyone has participated in that high school chemistry experiment where you mixed a packet of Fleischmann’s yeast with Welch’s grape juice and water, placed it in a one gallon bottle and sealed it with a one-way valve that allowed the carbon dioxide to escape but didn’t allow oxygen back into the bottle. After one week, voila! Home brewed Mogen David! That’s because in the absence of oxygen, Saccharomyces cerevisiae creates ethanol instead of lactic acid. Of course, if you purchase your vino directly from specialty wine shops, Saccharomyces is often assisted by wild-stock yeast like Kloeckera, Candida and Pichia to create that boutique bottle of Cabernet Sauvignon.

And when oxygen is readily available, Saccharomyces’ main contribution to the culinary world is carbon dioxide to make bread dough rise.
Saccharomyces’ bacterial cousins primarily contribute to cuisine by producing lactic acid which either pickles or produces new food products. Lactobacillus bulgaricus and Streptococcus thermophilus are the two main microbes responsible for the fermentation of milk to yogurt. Sauerkraut is assisted by the Leuconostoc species of bacteria to give the pickled cabbage its sour tang,  while Lactobacillus kimchi is involved in the lactic acid production and pickling of that classic Korean banchan, kimchi.

Then there are products where all of the culinary planets align to create a dish like no other, where the fermentative qualities of both yeast and bacteria combine to create a bread with a crisp crust, tender crumb and the unmistakable twang of lactic acid: Sourdough bread. It’s great on its own, slathered with a variety of toppings from plain fresh butter all the way up to savory duck, pork rillettes or even hollowed and toasted then filled with a hearty seafood chowder or bisque complete with an edible ‘bowl.” Another way to enjoy it is cubed and toasted for the perfect croutons to balance the sweetness in any vinaigrette. Because of its unique niche in culinary history, the primary bacteria that contributes to the real San Francisco treat was given the name Lactobacillus sanfranciscensis. And the great thing is you don’t have to only rely on the Boudin Bakery for your sourdough fix, you can actually create your own. And even if you fail (like I have on many occasions) in creating your own sourdough starter, look no further than the King Arthur Flour catalog for a ready to use sourdough starter. I was actually gifted about a half cup of starter from a friend who kept her starter propagated for several years. All it takes is removing one cup of starter that’s replaced with a slurry of one cup of flour and a half cup of water and leaving it at room temperature for several hours until the mass doubles. Then simply place it back in the refrigerator and repeat these steps every two to three weeks. Of course, you don’t waste the cup of active starter that’s removed, but use it to create sourdough bread, sourdough pizza crust, sourdough pancakes or sourdough biscuits. Or my new simple favorite, sourdough focaccia.

Rosemary Sourdough Focaccia. photo by Ryan Tatsumoto
Rosemary Sourdough Focaccia. photo by Ryan Tatsumoto

The following recipe for focaccia is as simple as it gets once you get your hands on sourdough starter. It’s simply mix, rest overnight, sprinkle and bake. There’s no lactic acid inducing muscle straining dough kneading, no punch down with a secondary rising and no cussing involved. Normally, focaccia dough is imbedded with “craters” for the olive oil right before baking but this dough is too delicate to abuse so simply drizzle and sprinkle your toppings then bake. My favorite pan is the Williams-Sonoma Goldtouch pan and I place it directly on top of my ceramic tiles for that extra kick of heat to brown the bottom, though a cast iron pan would accomplish the same.

Sourdough Focaccia
4 cups all-purpose or bread flour
2 cups water
2 tsp salt
2 tbsp extra virgin olive oil
1/2 tsp onion powder
1/2 tsp garlic powder
1 cup sourdough starter

1-2 tsp coarse sea or kosher salt
Fresh cracked black pepper
2 tbsp finely minced fresh rosemary
3 cloves finely minced fresh garlic
2 tbsp extra virgin olive oil

Tomato Sourdough Focaccia. photo by Ryan Tatsumoto
Tomato Sourdough Focaccia. photo by Ryan Tatsumoto

Mix the first seven ingredients until a uniform thick paste is achieved, about five minutes or so. Place the paste in a pre-greased 13” x 9” x 2-3” baking pan. Place the pan in a draft free location for eight to 12 hours. (I usually place my pan in the oven overnight.) After eight to 12 hours, the paste/dough should have risen two to three fold. Mix the minced garlic into the olive oil then drizzle evenly over the top of the paste/dough. Sprinkle evenly with the minced rosemary. Evenly sprinkle with the black pepper and salt. Baked in a pre-heated oven at 450 degrees for 20 to 25 minutes. Cool for 30 minutes before slicing.

So as you see, lactic acid isn’t just associated with the post-workout muscle burn, it can also be associated with a good burn … that’s if you have your daily dose of kimchi …

The Gochiso Gourmet is a column on food, wine and healthy eating. Ryan Tatsumoto is a graduate of both the University of Hawai‘i and UC San Francisco. He is a clinical pharmacist during the day and a budding chef/recipe developer/wine taster at night. He writes from Kane‘ohe, HI and can be reached at

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