Tortillas are Mexico’s most popular finger food. Whereas the thin, flat rounds of bread sold from street and market stalls are always baked and eaten fresh, packed industrial products from supermarkets must stay soft and flexible for weeks. By using highly functional enzyme compounds, manufacturers can achieve a shelf life of around 90 days.
Mexican cooking is like the country itself: colorful, diverse, and full of surprises. In the south, the traditional recipes of the Mayas and Aztecs are still popular — prepared mostly with beans, maize, chili and tomatoes. In the north, the eating habits of the Spanish conquistadores have asserted themselves, with dishes containing pork and rice. And in the coastal areas of the east, fish and seafood bring a Caribbean flair to the table.
In 2010, the UNESCO honored this extraordinary diversity by adding the Mexican cuisine to the official list of the Intangible Cultural Heritage of Humanity.
Despite all the regional differences, one culinary preference can be traced throughout the country. Tortillas — thin rounds of bread made from maize or wheat flour — are an essential part of every meal. They might be called the real star of Mexican cooking.
Tortillas are always eaten with the fingers — and Mexicans are immensely creative where their favorite finger food is concerned. Filled, rolled, deep-fried or grilled, tortillas are the indispensable base for tacos, quesadillas, burritos, huaraches, enchiladas or tostadas. Typical accompaniments are baked beans, grilled meat, cheese, vegetables, avocados and salad.
A day without a tortilla is unthinkable for a Mexican. The arterial roads of the cities are lined with taco fast-food chains, one next to the other. But the authentic national cuisine is mainly to be found in the markets and family-run taquerias, where the dough pieces are prepared in the traditional manner on thin, hot griddles called comales. Freshness is imperative. The cooks (taqueros) often have only a tiny space to work in, and yet they conjure up an astonishing diversity of flat bread specialties from regional ingredients and seasonings. The business cards of every taqueria are its homemade spicy salsas and creamy sauces (mole) that are served for dipping and seasoning.
Increasing acceptance of wheat tortillas
In the artisan sector and in private households, tortillas are generally made from maize (corn) flour, whereas wheat flour is the more common raw material in the baking industry. Wheat flour tortillas have a softer consistency and are easier to roll and fold. The ideal raw material is hard red winter wheat with a protein content between 10.5% and 11.5%, to which up to 30% soft wheat can be added.
Mexican consumers have precise ideas as to what their wheat flour tortillas should be like. A perfect tortilla should have a uniform shape and a pale beige color with a scatter of brown toasted spots and must neither break nor become soggy when prepared.
The following is a typical recipe for flour tortillas:
- 100% flour
- 1.7% salt
- 10% to 12% shortening
- 1.8% baking powder, double-acting
- 50% to 55% water
The dough is kneaded slowly, shaped into portions of 30 to 90 grams, left to rest for at least 15 minutes, then placed between the plates of a tortilla press (hot press) heated to about 400 degrees F (200 degrees C). A pressure of ca. 1,100 PSI (76 bar or 7.6 MPa) gives the bread its characteristic shape. The diameter of the tortilla is around 5.9 to 7.5 inches (15 to 19 cm), its thickness 1.5 to 3 mm. Through direct contact heating, the starch in the dough already begins to paste in the press.
The subsequent baking process takes less than a minute. At industrial bakeries “triple pass” ovens are widely used. The special construction of these multi-tier, gas-fired ovens permits baking at high temperatures in the turbo mode.
Focus on shelf life
The crucial topic for industrial producers is the shelf life of the tortillas. Some retail chains demand a minimum shelf life of three months for wrapped bread, and even periods of up to 120 days are sometimes discussed.
The main reason for this is the logistic aspect. It may take several weeks for the wrapped products to be delivered to the most distant parts of the country or exported abroad.
To ensure that the tortillas remain edible in the customer’s home for as long as possible subsequently, they must have a shelf life of several months.
Whereas microbiological problems can be solved quite easily with preservatives like sorbic acid (EMCEsorb), propionic acid (EMCEprop) and lactic acid (EMCEtric LA), the product-specific attributes present a much bigger challenge.
For mills, these targets can only be achieved with the use of highly functional flour improvers. To ensure that the tortillas stay soft and succulent for months and do not stick together in the pack or break when filled or rolled, precise interaction between enzymes, emulsifiers, oxidizing agents and hydrocolloids is necessary.
Mühlenchemie offers a toolbox with a host of different agents that ensure the right solution, depending on the application and the quality of the flour. They include the enzyme system Flexizym, the dough softeners EMCEsoft and EMCErelax, baking premixes from the EMCEbest series and the ascorbic acid product ELCO C, that is suitable for flour applications.
Short list of ingredients
Besides the shelf-life topic, some retail chains have another requirement that is important to them in connection with tortillas: namely a label-friendly list of ingredients. With innovative raw material concepts, the baking and milling industry can find appropriate, modern answers to clean label questions. Synergistically-acting flour improvers consisting solely of enzymatic components can replace emulsifiers like mono and diglycerides, SSL or CSL partially or even wholly.
The following overview shows how the most common problems that occur in the production of tortillas can be solved with raw material-based or technological measures:
Problem: Sticky dough
Possible causes: Prolonged mixing and resting; high amylolytic activity; high water temperature; low-fat formulation.
Solution: Adjust process parameters; use flour with low enzymatic activity; add Gloxy TGO; add fat; use emulsifiers e.g. Mulgaprime 90 F or Mulgaprime SSL.
Problem: Poor machinability of the dough
Possible causes: An inappropriate amount of water; flour too weak or too strong.
Solution: Choose different flour; incorporate shortening or emulsifiers such as monoglycerides (e.g. Mulgaprime 90 F); change mixing and resting times.
With weak flour: use oxidizing agents like ascorbic acid or azodicarbonamide or oxidizing enzymes to strengthen the dough (e.g. ELCO C, OXEM, EMCEvit C). With strong flour: use reducing agents such as cysteine (e.g EMCEsoft P / EMCErelax).
Problem: Drying and rapid staling of tortillas
Possible causes: High Falling Number (low intrinsic enzyme activity); dough too firm (insufficient water addition); low water retention; use of thermosensitive amylolytic enzymes.
Solutions: Use Flexizym Plus or Flexizym T-FX (for clean labeling) to reduce starch retrogradation and to prolong the softness; increase water addition; add emulsifying agents (e.g. Mulgaprime SSL), use hydrocolloids like guar gum or gum arabic to increase water retention (e.g. EMCEgum).
Problem: Short shelf life (microbial); tortillas are rapidly decomposed by microorganisms.
Possible causes: pH of the product is above the optimum for wheat tortillas of 5.3 to 5.5; high bacterial count in the process environment.
Solutions: Adjust the pH with acidifying agents and control the addition of leavening agents; check hygiene conditions; use air filters, particularly for ventilation in the packaging area; add preservatives such as propionate (e.g. EMCEprop P).
Problem: Tortillas stick to the machine during production.
Possible causes: Poor wheat quality; dough overmixed; dough temperature too high.
Solution: Improve gluten quality with EMCEvit C or Gluten Enhancer GE 22; use less reducing ingredients or shorten mixing time.
Problem: Frayed edges of the tortillas
Possible causes: Curling of the dough leaving the hot press; cupping caused by a wide temperature difference between the top and bottom plates (>50 to 70 degrees F /10 to 20 degrees C).
Solution: Bring the temperatures of the top and bottom plates into line.
Problem: Translucent tortillas
Possible causes: Dough too warm or overmixed; dwell time too long; press temperature or press pressure too high; too much reducing agent; too much fat in the formulation, unsuitable type of fat.
Solution: Adjust dough characteristics and mixing parameters; check recipe and reducing agents; adjust equipment.
Stern Ingredients México offers customer service with its own pilot tortilla plant
Tortillas are the shooting star in the international fast-food sector and have long competed for popularity with burgers, pizza, etc. According to the industry service Market Research Future, “The global tortilla market has been witnessing a constant demand over the last few years and is projected to reach $48.51 billion at a CAGR of 5.1% by 2023.”
The biggest markets are still North and Latin America, but more consumers in Asia, Africa and Europe are acquiring a taste for “Tex-Mex” cuisine and boosting demand.
Stern Ingredients México (SIMEX), the Mexican affiliate of the flour improvement specialist Mühlenchemie, has prepared itself for this continuing boom and invested in a tortilla laboratory of its own. At the customer’s request, product optimization and innovations are carried out on the variable pilot plant. How can a larger proportion of soft wheat be integrated? What is the effect of replacing lard with vegetable oil in the recipe? What baking powder is the best raising agent? Which product is most suitable for delaying mold formation on the surface of the baked foods?
The SIMEX applications technologists go on analyzing the recipes and production parameters until the client’s specifications have been met in full.
This unique customer service is appreciated far beyond the borders of Mexico. Tortilla producers around the globe send their flour samples to SIMEX, asking for recommendations for optimizing their production processes.
Sven Mattutat is a product manager with Mühlenchemie. He may be contacted at firstname.lastname@example.org.