Tortilla texture

The texture of tortillas could be determined using the bending test described by Suhendro et al. (1998b). The bending technique is sensitive to changes in tortilla texture throughout storage or equilibration. —continued... 

The objective rollability test uses a custom-designed rollability fixture consisting of an acrylic cylindrical dowel and a metal chain that connects the cyUnder dowel to the texture analyzer arm. The force and work required to pull the axle is determined. The technique is fast, simple, and sensitive to changes in tortilla texture (Suhendro et al. 1998a). 

Suhendro, E.L., Akneida-Dominguez, H. Rooney, L.W., and Waniska, R.D. 1998a. Objective reliability method for corn tortilla texture measurement. Cereal Chem. 75(3) 320-324. 

Texturization enables the creation of more expanded products with boosted protein levels, which are texturally firmer and crispier products, easier to break than the t)q)ical commeal or cornmeal without TWPI. For example, we developed several directly expanded high-protein com meal products containing 30 g/100 g WPC (WPC80) and WPI. The protot)q5e products were pretzels, com chips, and tortilla chips (Onwulata, 2010). 

The chips from the toaster-oven then pass through an equilibrator. This is a chamber with open sides. The chips pass through a series of special conveyor belts. The object is to achieve an even distribution of moisture in the chips. This also makes the chip color and texture more uniform. Moisture of the chips at this stage is around 40% for masa made from cooked com and 30% to 35% for the chips made from dry corn masica. (See Figure 13 for the tortilla system before frying). Temperature of the chips reaches below 100°F (38°C) in the equilibrator. 

Potato chips are fried to a final moisture level of 3% or less, which accounts to an of about 0.2. Tortilla chips, corn chips, and other snacks have a final moisture content of <3%. From a study on potato chips a moisture content of 3.57% was the point at which a taste panel rejected the chips because of their texture deterioration [39]. Moisture absorption and the consequent deteriorative changes can be prevented by the use of packaging materials with appropriate moisture barrier properties. In this case the shelf life of the products can be extended to several months. If the packaging material is not transmitted by light and if the air inside the packaging is replaced by an inert gas, e.g., nitrogen, a considerably longer shelf life can be obtained. 

Maize kernels, lime, and water are the basic ingredients used in alkaline cooking for making masa and table tortillas. Other additives are connmonly nsed, especially when processing dry masa flours. Hydrocolloids or gums, anulsiliers, acidulants, preservatives, and enrichment mixes are used. These additives improve microbial and textural tortilla shelf life and nutritional properties. 

Emulsifiers also improve the textural shelf life of table tortillas. They help delay staling and prodnce softer and more reliable tortillas. The most effective emulsifier is sodium-stearoyl-2-lactylate or SSL. This linear-shaped emulsifier has the ability to bind inside amylose helixes, retarding retrogradation. Commercial lecithin and monoglycerides are also used alone or in combination with SSL (Sema-Saldivar et al. 1990). 

Procedure to evaluate alkaline cooking properties of kg lots of maize. Kernels are placed in a perforated nylon bag, Ume cooked, steeped, washed and stone-ground into masa. The masa is formed into tortillas or tortilla pieces and cooked in a small-scale three-tier baking oven. Yields of tortillas are calculated from the original moisture content of the grain and the amount of tortillas obtained. Resulting tortillas can be used for texture, color, organoleptic, and shelf-life stabihty tests. 

Blue maize Floury or soft-textured maize that contains blue-purple coloration in the aleurone layer due to the presence of anthocyanins and flavonoids. Thus, it is considered a nutraceutical food and is generally sold as flour, tortilla chips, and table tortillas. 

Lecithin One of the main phospholipids found in nature with important implications in metabolism and cell membranes. Lecithin is considered an important nutraceutical compound because it lowers blood cholesterol and is key to the synthesis of choline. Chemically, lecithin is the emulsifier phosphatidyl choline, and commercial lecithin consists of a mixture of different phospholipids such as phosphatidyl ethanol amine, phosphatidyl inositol, and phosphatidyl serine. Most commercial lecithin is obtained during the refining process of soybean oil. The egg yolk is also a rich source of lecithin. Lecithin is widely used in the baking, cookie, and wheat flour tortilla industries to improve dough machinability, improve texture, and retard staling. It is generally used from 0.1%-1%. 

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