Tortilla treatment

Bakery Products. Sorbates are used in and/or on yeast-raised and chemically leavened bakery products. The internal use of sorbates in yeast-raised products at one-fourth the amount of calcium—sodium propionate that is normally added provides a shelf life equal to that of propionate without adversely affecting the yeast fermentation. Sorbates added at one-tenth the propionate level reduce the mix time by 30% (126). This internal treatment combined with an external spray of potassium sorbate can provide the same or an increased shelf life of pan breads, hamburger and hot-dog buns, English muffins, brown-and-serve roUs, and tortillas. The total sorbate useful in or on these baked goods ranges from 0.03 wt % for pan breads to 0.5 wt % for tortillas 0.2—0.3 wt % sorbic acid protects chemically leavened yellow and chocolate cakes (127). Emit-pie fillings and icings can be protected with 0.03—0.1 wt % sorbates. 

Torres, P., Guzman-Ortiz, M. and Ramirez-Wong, B., Revising the role of pH and thermal treatments in aflatoxin content reduction during the tortilla and deep frying processes, J. Agric. Food Chem., 49, 2825, 2001. 

The Role of Lime in the Alkaline Treatment of Corn for Tortilla Preparation... 

Lime Treatment of Corn for Tortilla Preparation. The lime treatment of com for tortilla preparation consists of the following (see Figure 2) a 3 1 mixture of lime water (1.3%, w/v) and dry com grains is... 

Zein, which is the major protein in corn, was chosen because it contains no lysine. This precluded the formation of LAL during alkali treatment. Therefore, any changes in digestibility or uptake could be attributed to racemization effects alone. Additionally, we were interested in comparing the effects of sodium hydroxide treatment with the effects of calcium hydroxide treatment because lime is used in the preparation of corn meal for use in tortillas. If the traditional lime treatment of com meal is unnecessarily harsh, it could have important nutritional consequences because a large segment of the Mexican population obtains much of their dietary protein in the form of tortillas (22). 

Sources. Niacin and substances that are convertible to niacin are found naturally in meat (especially red meat), poultry, fish, legumes, and yeast. In addition to preformed niacin, some L-tryptophan found in the proteins of these foods is metabolized to niacin. Niacin is also present in cereal grains, such as corn and wheat. However, consumption of corn-rich diets has resulted in niacin deficiency in certain populations. The reason for this is that niacin exists in cereal grains in bound forms, such as the glycoside niacytin, which exhibit little or no nutritional availability. Interestingly, niacin deficiency is not common in Mexico and Central America even though the diets of those in these countries are based on com. Alkaline treatment, such as soaking corn in a lime solution—the process used by the populations of Mexico and Central America in the production of com tortillas—yields release of bound niacin and increased availability of the vitamin. 

American natives knew that corn needed to be processed to be nutritious in a process known nixtamalization (alkaline treatment commonly used in Mexico and Central America in the preparation of tortillas, tamales and hominy) or ingested as immature ears. This knowledge was lost when Christopher Columbus returned from the New World with samples of the new seed. 

Treatment of cereals with alkali (for example soaking overnight in calcium hydroxide solution, as is the traditional method for the preparation of tortillas in Mexico) releases much of the nicotinic acid. This may explain why pellagra has always been rare in Mexico, despite the fact that maize is the dietary staple. Up to 10% of the niacin in niacytin may be biologically available as a result of hydrolysis by gastric acid. 

RECENT DEVELOPMENTS IN THE TREATMENT AND PREVENTION OF PROTEIN-ENERGY MALNUTRITION, A variety of new high-protein food products has been developed by large food concerns for distribution in developing countries. Many of these products are currently being test marketed in Latin American countries. For example, the protein quality of tortilla flour in Mexico has been enhanced by the mixing of soy flour with the traditional corn flour. 

Cereals are considered one of the best sources of B-vitamins thiamin, riboflavin, niacin, pyridoxine, and folates, but a poor source of fat-soluble vitamins and vitamin Bi2. Most B-vitamins are associated with the aleurone. The niacin associated with cereals is found in free and bound forms. Bound niacin is not well utilized by the human system. Interestingly, the alkaline treatment of maize for production of tortillas and other traditional food products increases niacin bioavailability because the alkali and heat treatment breaks the glycosidic bond that binds free niacin with the other components (Chapters 9 and 17). 

Serna-Saldivar, S.O., Rooney, L.W., and Greene, L.W. 1992. Effects of lime treatment on the bioavailability of calcium in diets of tortillas and beans Bone and plasma composition in rats. Cereal Chem. 69 78-81. 

The flavor formed by the cooking of fragrant rice (e.g., Basmati) is described as popcornlike, hence it is not surprising that 2-acetyl-1-pyrroline is the character impact volatile (51). In masa corn tortillas, 2-aminoacetophenone provided the character impact resulting from the lime treatment of corn (53) in corn chips, its contribution is modified by 2-acetyl-1-pyrroline and unsaturated... 

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