1.What are Thickeners?
Thickeners are hydrocolloids that are used to increase the viscosity of liquids or semi-solids
without significantly affecting their other properties. In the food industry, thickeners are
commonly employed to alter the physical form of foods, imparting a viscous and desirable texture
while also serving as emulsifiers, stabilizers, or suspending agents. The history of human use of
thickeners is quite lengthy, dating back to ancient times when natural substances were first
utilized for thickening purposes. With the advancement of science and technology, the application of
thickeners has gradually expanded to numerous other industries. In the food industry, thickeners
have become increasingly prevalent, finding their way into the production of various foods such as
ice cream, jellies, and sauces. These additives not only enhance the taste and texture of foods but
also improve their stability and extend their shelf life.
Moreover, thickeners have gained widespread application in industries such as cosmetics, paints,
adhesives, and pharmaceuticals. In these sectors, they play a crucial role in improving product
performance and meeting market demands for high-quality goods. A significant milestone in the
development of thickeners was the introduction of synthetic thickeners. In the 1950s, the first
fully synthetic thickener — polyacrylic acid-based thickener — was brought to the market. Since
then, various synthetic thickeners have been developed and widely used in diverse fields. These
synthetic thickeners often exhibit superior thickening effects and stability, satisfying more
complex application requirements. Overall, the history and evolution of thickeners have transitioned
from natural to synthetic and from simple to complex. With the ongoing progress of technology and
rising concerns for food safety and environmental protection, the application and development of
thickeners are expected to continue advancing.
2.How are Thickeners classified?
Starch-based thickeners: Common examples include corn starch and tapioca starch, which are widely
used in food applications. They increase the viscosity of foods through the gelatinization reaction
of starch, such as in the production of jam, sauces, juices, and yogurt.
Gum-based thickeners: These have a high molecular weight and can react with water molecules to form
a network structure, thereby increasing the viscosity of foods. Common gum-based thickeners include
pectin, gelatin, and agar, which are widely used in the production of jam, jelly, and soft candies.
Plant gum-based thickeners: These are natural high-molecular-weight substances extracted from plants
with good water solubility and viscosity. Common plant gum-based thickeners include guar gum and
locust bean gum, which are widely used in the production of ice cream, dairy products, and
condiments.
Synthetic thickeners: These are artificially synthesized substances with good water solubility and
viscosity. Common synthetic thickeners include xanthan gum and carrageenan, which are widely used in
the production of jam, beverages, ice cream, and other foods.
3.How to use Thickeners?
The first step is to choose a suitable thickener according to the type of food and the effect that
needs to be achieved. For example, gelatine is suitable for use in the production of products such
as jellies and confectionery, while carrageenan is suitable for use in the production of sauces and
condiments. For some oil-based thickeners, such as gelatine, it is necessary to soak them in cold
water for several hours before use to avoid the production of a large number of air bubbles when
heated, as well as stiff lumps resulting from incomplete expansion. Allow to fully expand, and then
heat the gelatine underwater, with the temperature of the gelatine controlled below 70°C. Then,
ensure that the thickener is completely dissolved in the food. This usually involves the gradual
addition of the thickener to the foodstuff with continuous stirring until it is completely
dissolved. It is important to control the amount of thickener added precisely, depending on the type
of food and the process. Too little may result in the food not achieving the desired consistency,
while too much may make the food taste too sticky and affect the quality. The exact amount to be
added should be referred to the product formulation or professional advice.
4.What are Thickeners used for in food industry?
Food thickeners, as additives, are primarily used to improve and increase the viscosity of foods or
to maintain the color, aroma, taste, and stability of liquid and jelly-like foods through gelation
in aqueous media. Here are the main applications of food thickeners:
Improving food's physical properties: Food thickeners can increase the viscosity of foods, resulting
in a better taste and texture. For instance, in jams, sauces, juices, and yogurt, thickeners can
make the products more concentrated and smooth.
As gelling agents: In jelly-like foods such as jellies and puddings, thickeners help create a stable
gel structure, maintaining the shape and texture.
Enhancing the quality of meat products: In meat products, thickeners can improve the taste, binding,
and water-holding capacity, reducing fat separation and increasing yield. For example, adding soy
protein to ham products can increase its yield and protein content; adding gelatin to canned meat
products can enhance the surface gloss and elasticity.
Improving the quality of flour-based products: In noodle products, thickeners can increase the
toughness and smoothness, reduce cooking loss, add chewiness, and improve the taste.
As emulsifiers and stabilizers: In foods like ice cream and dairy products, thickeners can act as
emulsifiers and stabilizers, making the products more stable and delivering a smoother texture.
5.Are Thickeners harmful to humans?
Whether thickeners in food additives are harmful to humans depends mainly on their use and type.
Most thickeners come from natural foods such as carrageenan, starch, pectin, etc. They are also a
kind of dietary fiber, and some intake of such gums by the human body is also advocated in
nutrition. In addition, in some thickeners such as gelatin, animal gelatin, etc., the main component
is protein, which, after digestion, is broken down into amino acids and then participates in the
body's metabolism and is able to absorb and use the nutrients. Secondly, thickeners can play a
variety of roles in food processing, such as improving the texture, taste, stability, etc., and can
extend the preservation time of food. As long as they are used reasonably within national standards,
food thickeners are not harmful to human health. However, some thickeners may have adverse effects
on specific groups of people. For example, some thickeners (e.g., maltodextrin, modified starch) may
cause an increase in blood glucose and should, therefore, be used with caution by people with
diabetes. In addition, although most thickeners are safe, excessive or improper use may still pose
potential risks to human health.
