4-practical lesson: Starch and Molasses

Plan:

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• Classification of starch
• Production of starch
• Nutritional value and quality of starch
• Quality requirements for starch
• Types of starch products
• Packaging and storage of starch

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• Monosaccharides – monosaccharides (e.g., glucose, fructose, galactose)
• Disaccharides – disaccharides (e.g., sucrose, lactose, maltose)
• Polysaccharides – polysaccharides (e.g., starch, glycogen, cellulose)

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• Starch (formula – (C6H10O5)n) is a white, granular organic substance produced by all green plants.

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Starch content in plants

Tuberous vegetable crops (potatoes)

Legume seeds (beans, peas, lentils)

Cereal crops (corn, rice, wheat, oats, rye, barley)

Use of starch�Starch is widely used in cooking, the food industry (in the production of ice cream, in baking, in sausage production), as well as in medicine and perfumery.

Starch is an important component of food products, serving as a thickener and binding agent.

�In some cases, it is present in the raw materials processed into food products (for example, bakery products).

�In other cases, it is added to give the product certain properties – it is widely used in the production of puddings, soup concentrates, kissels, sauces, salad dressings, fillings, and mayonnaise; one of the components of starch – amylose – is used for edible films and coatings.

Physico-chemical properties of starch�

The main physico-chemical properties of starch that are of great importance for food products include the ability of starch to gelatinize, the viscosity of gelatinized solutions, and their ability to form gels.

Starch gelatinization occurs when it is heated in water.

Types of starch granules under a microscope

1 – potato starch, 2 – wheat starch, 3 – oat starch, 4 – corn starch, 5 – rice starch

Types of starch

Potato starch – has the largest granules (80–110 μm), oval in shape with concentric grooves, produced from potato tubers, capable of swelling in water, and when heated with it forms a viscous transparent paste.

Wheat starch – has granules of flat elliptical or round shape (20–35 μm), has low viscosity, and is more transparent than corn starch.

Corn starch – generally has granules of irregular polyhedral shape (5–25 μm), produced from white-grain varieties of corn, and forms an opaque paste of low viscosity, milky-white in color, with a characteristic odor and taste of corn kernels.

Rice starch – has the smallest granules (3–8 μm) of polyhedral shape and forms a paste of low viscosity.

Starch production technology

• Defects of Starch

� Starch defects mainly occur due to violations of the production technology or storage conditions.�These include the presence of mechanical and foreign impurities, odor and taste of spoiled product (fermentation), crunchiness when chewing caused by mineral impurities (sand), gray color of starch, and its increased moisture content.�Starch with such defects is not allowed for sale in retail trade, but may be used for technical purposes.

Packaging of Starch�Starch must be packed in double bags. It may also be packaged in small paper (cartons or bags) or polymer containers with a net weight of up to 1000 g.�Cartons or bags must be placed in wooden, plywood, or corrugated cardboard boxes with a net weight of no more than 30 kg.

Storage of Starch�Starch is stored at a relative air humidity of no more than 75%, avoiding sharp temperature fluctuations.�The optimal storage temperature is about 10 °C.�Warehouses must be clean, well-ventilated, and free from pests.�Proper product neighborhood must be observed.�Shelf life from the date of production: potato and corn starch – 2 years, wheat starch – 1 year.

1. Molasses (Starch Syrup)

Production: Obtained by hydrolysis of starch (usually corn, wheat, or potato starch) using acids or enzymes.

Composition: Mainly dextrins, maltose, and small amounts of glucose.

Properties: Thick, transparent, colorless or slightly yellow syrup.

Uses:

• In confectionery (candies, caramel, pastries)
• In bread-making to keep products soft and prolong shelf life
• In ice cream and beverages to reduce crystallization

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2. Sago

Production: Derived from the starch of the sago palm trunk, dried and formed into granules.

Composition: Up to 90% starch, small amounts of protein and fiber.

Properties: White or light granules, become translucent when boiled.

Uses:

As porridge, soups, and desserts

Easily digestible, used in dietary and baby foods

3. Glucose (Dextrose)

Production: Obtained by complete hydrolysis of starch using enzymes.

Composition: Monosaccharide, C₆H₁₂O₆.

Properties: Sweet taste, highly soluble in water, quickly absorbed by the body.

Uses:

• In medicine as an energy source (glucose solutions)
• In confectionery to provide sweetness and stability
• In drinks and canned foods to prevent crystallization

4. Maltodextrin

Production: Partial hydrolysis of starch (not fully broken down).

Composition: Mixture of carbohydrate polymers without proteins or vitamins.

Properties: White powder, easily soluble in water, almost tasteless.

Uses:

• Energy supplement for athletes
• Ingredient in baby foods
• In industry – used in dry drink mixes, sweets, sauces, chips as a texture enhancer

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