Types, Properties, and Applications of Modified Starches

People have been using starch for centuries, from cementing strips of papyrus in ancient Egypt to preventing ink penetration in ancient China. In the 1500s, starch was introduced to England and France for use in laundry and fashion. By the 1930s, scientists developed many starch products. Starches from plants like wheat, potato, rice, maize, and more are important sources of carbohydrates in human diets. Food processors prefer starches with better qualities, so they use modifications to improve their properties for specific uses.

PregelatinizationCold-water dispersibilityUseful in instant convenience foods
Partial acid or enzymatic hydrolysisReduced molecular weight polymers, exhibit reduced viscosity, increased retrogradation, and setbackUseful in confectionery, batters, and food coatings
Oxidation/bleachingLow viscosity, high clarity, and low-temperature stabilityUsed in batters and breading for coating various foodstuffs, in confectionery as binders and film formers, in dairy as texturizers
Pyroconversion (dextrinization)Low to high solubility depending on conversion, low viscosity, high reducing sugar contentUsed as coating materials for various foods, good film-forming ability, and as fat replacers in bakery and dairy products
EtherificationImproved clarity of starch paste, greater viscosity, reduced syneresis, and freeze-thaw stabilityUsed in wide range of food applications such as gravies, dips, sauces, fruit pie fillings, and puddings
EsterificationLower gelatinization temperature and retrogradation, lower tendency to form gels, and higher paste clarityUsed in refrigerated and frozen foods, as emulsion stabilizers and for encapsulation
Cross-linkingHigher stability of granules toward swelling, high temperature, high shear, and acidic conditions

Used as viscosifiers and texturizers in soups, sauces, gravies, bakery, and dairy products
Dual modificationStability against acid, thermal, and mechanical degradation and delayed retrogradation during storageUsed in canned foods, refrigerated and frozen foods, salad dressings, puddings, and gravies
GraftingBetter biodegradability and thermal stability, higher hydrodynamic radius, and hydrodynamic volumeUsed for filmmaking, during delivery, water-absorbing materials, and textile
Table 1. Some Properties and Applications of Modified Starches

Starch can be modified in different ways, including using enzymes, physical methods, or chemicals. Enzymes are used to break down or extend starch, creating maltodextrin, modified starches, or syrups. Physical modification can include heat treatments or non-thermal processes. Chemical modification involves changing the starch through methods like etherification or cross-linking. Scientists can study the changes in starch through tests like microscopy, DSC, and RVA/dynamic rheometer. There is growing interest in the nutritional value of starch, and it is categorized based on its effect on blood sugar levels. Some modified starches have been shown to have lower glycemic loads, providing health benefits.

EnzymaticDegradationFood-grade enzymes such as amyloglucosidase, pullulanase, α-amylase, β-amylase, and isomerase are used to produce syrup, cyclodextrin, and debranched starch
EnzymaticChain extensionβ-amylase are used to retard retrogradation

Amylosucrase are used to extend certain length
α-glucan chain
PhysicalHydrothermalHeat-moisture treatment is heating starch at a temperature above its gelatinization point with insufficient moisture

Annealing is heating starch slurry at a temperature below its gelatinization point for prolonged periods of time
PhysicalPregelatinizationPregels/instant/cold-water swelling starches are prepared using drum drying/spray cooking/ extrusion/solvent-based processing
PhysicalNonthermalRadiation (gamma, electron beam, and ultraviolet irradiation) induces free radicals and changes starch molecular fragments resulting in reduction of viscosity and high water solubility

Sonication is applied sounds at 20-100 kHz to homogenize, emulsify, mix, extract, dry, and disrupt starch

High-pressure processing is used to gelatinize
starch at pressure above 400 MPa but maintains
its granular morphology
ChemicalConversionPyroconversion (dextrinization) and pyrodextrin is prepared by dry roasting acidified starch

Partial acid hydrolysis by hydrochloric acid or ortho-phosphoric acid or sulfuric acid

Alkali treatment with sodium hydroxide or potassium hydroxide

Oxidation/bleaching treatment with peracetic acid and/or hydrogen peroxide, sodium hypochlorite or sodium chlorite, sulfur dioxide, potassium permanganate, or ammonium persulfate
ChemicalSubstitutionHydroxypropyl starch-Esterification with propylene oxide

Starch acetate-Esterification with acetic anhydride or vinyl acetate

Acetylated distarch adipate-Esterification with acetic anhydride and adipic anhydride

Starch sodium octenylsuccinate-Esterification by octenylsuccinic anhydride
ChemicalCross-linkingMonostarch phosphate-Esterification with ortho-phosphoric acid, sodium or potassium ortho-phosphate, or sodium tripolyphosphate

Distarch phosphate-Esterification with sodium trimetaphosphate or phosphorus oxychloride

Phosphated distarch phosphate-Combination of treatments for monostarch phosphate and distarch phosphate
ChemicalDuel modificationAcetylated distarch phosphate-Esterification by sodium trimetaphosphate or phosphorus oxychloride combined with esterification by acetic anhydride or vinyl acetate

Hydroxypropyl distarch phosphatedEsterification by sodium trimetaphosphate or phosphorus oxychloride combined with etherification by propylene oxide
Table 2. Different Types of Starch Modification Methods

Leave a Reply

Your email address will not be published. Required fields are marked *