Cereals and Cereal Foods - NT

Cereals and Cereal Foods

  • Cereal grains are the seed-grains of cultivated grasses, grown for their highly nutritious edible seeds.

Common Types of Grains

  • There are 8 common cultivated grains:

    • Wheat

    • Corn

    • Oats

    • Rye

    • Millet

    • Barley

    • Sorghum

    • Rice

  • Ancient wheats include einkorn, emmer, spelt, and kamut.

Pseudo-Grains

  • Pseudo-grains or false grains come from broad-leaf plants and are not true grains. Examples include:

    • Amaranth (high-quality protein, and contains all essential amino acids)

    • Quinoa

  • Pseudo-grains are gluten-free and digestible, making them suitable for coeliac individuals.

Wheat Classification

  • Different species of wheat yield different flours:

    • Triticum vulgare: for bread.

    • Triticum durum: for pasta.

    • Triticum compactum: for cake.

Types of Wheat

  • Spring Wheat:

    • Sown in spring, harvested the same year.

    • Protein content: 12-14%.

  • Winter Wheat:

    • Sown in autumn, harvested the following year.

    • Protein content: less than 10%.

Wheat Strength

  • Strength of wheat is determined by gluten protein content:

    • Strong flour: for breadmaking.

    • Soft flour: for biscuits.

Wheat Structure and Composition

  1. Bran (13%) - Tough fibrous skin; contains dietary fibre and minerals.

  2. Germ (2%) - Contains fat, protein, and B-vitamins.

  3. Endosperm - Largest part, high in carbohydrates and some protein.

Production of Wheat Flour

  • Screening: Removal of particles through sieves.

  • Scrubbing & Washing: Removes dirt and dust.

  • Conditioning: Achieves uniform moisture.

Milling Methods

  1. Stone-Milling: Produces whole wheat and specialty flours.

  2. Roller-Milling: Three stages—breaking of grain and reduction into fine flour.

  3. Fragmentation Milling: Further refines flour into different particle sizes.

Flour Nutritional Content and Types

  • Extraction Rate indicates flour quality:

    • 100%: whole wheat (most nutritious)

    • 70-72%: white flour (less fiber).

  • Dietary fiber contents vary:

    • White: 3.1g/100g

    • Brown: 6.4g/100g

    • Wholewheat: 9.0g/100g

Gluten Formation

  • Gluten is formed when gliadin and glutenin proteins are mixed with water:

    • Gliadin: Elastic and extensible

    • Glutenin: Strong and tough

  • Manipulation of dough affects gluten development, leading to desired properties in baked goods.

Starch in Flour

  • Two types of starch molecules:

    • Amylose: Long, thickening sauces when heated.

    • Amylopectin: Branching structure, produces a clear gel when cooked.

Gelatinization Process

  • Occurs when flour is heated with liquid, causing starch granules to swell and thicken the mixture.

Types of Flour

  1. Weak/Specialty Flour: Low protein (~8%); for cakes and pastries.

  2. Medium Flour: All-purpose (10% protein); versatile.

  3. Strong Flour: High protein (~17%); for breadmaking.

Bread Making Process

  • Ingredients: Flour, water, yeast, salt, optional ingredients (milk, sugar, etc.).

  • Yeast ferments and produces CO2, helping dough rise.

Key Points on Cooking Pasta

  • Use plenty of boiling water, add salt after boiling, and avoid adding oil to water. Test for doneness close to al dente. Drain properly when serving.

Nutrient Content of Bread

  • 10% Protein, 40% Carbohydrates, dietary fiber based on flour type.

  • Vitamin contributions diminish with milling and processing; whole grain is preferred for maximum nutrition.

Rice Varieties and Cooking

  • Types include short grain, long grain, medium grain, brown, white, and easy-cook rice, with controlled cooking needed for best nutrient retention.

Storage of Cereals

  • Store in tight containers to prevent spoiling; keep dry and clean to avoid pests.