What Are Emulsifiers & Stabilisers?
Many of the popular foods we know today are combinations of natural components that may otherwise not naturally get along with one another. For example, water and oils when mixed together will separate at the first given chance. However, they remain mixed together in an emulsion, i.e. processed foods like low-fat spreads, margarine, mayonnaise, salad dressings, ice cream and other dairy products.
Emulsifiers and stabilisers are both classified as additives. The main purpose of these additives is to maintain a uniformed texture and to prevent the separation of essential ingredients in food products. While emulsifiers help to mix together substances which do not easily mix, such as oil and water, stabilisers on the other hand, ‘stabilise’ the desired consistency and stops these substances from separating again after they have been mixed.
A proper mix of additives always tends to form more stable mixtures as compared to the use of a single emulsifier or stabiliser, and achieves higher functionality as compared to a single additive. Choosing the right mixture of emulsifiers and stabilisers is crucial to ensure a smooth surface, a creamy texture and full water retention for end products.
Common Food Emulsifiers
Polyglycerol Polyricinoleate (PGPR)
PGPR is a fantastic emulsifier when it comes to chocolate applications. It works as a viscosity modifier that improves the moulding properties of molten chocolate for chocolate coatings to flow properly during the enrobing process. PGPR also has the ability to limit fat bloom and can be used in combination with lecithin as they have complementary rheological properties for an optimal control of chocolate rheology.
PGPR can also be used as an emulsifier in tin-greasing emulsions for the baking trade, margarine and low-fat spreads. It can be used alone or blended with monoglycerides to obtain an optimal quality and cost ratio.
Ammonium Phosphatide (AMP)
Using the right emulsifiers could offer chocolate manufacturers numerous ways to save costs, achieve uniformity and create more stable end products as well as simplify the production process. This non-GMO sunflower-based emulsifier can be introduced into applications that are sensitive to off-flavours such as crumb chocolates with its low content of cocoa solids, white chocolate or white confectionery spreads. Also, the addition of emulsifiers could help to avoid the thickening of chocolate mass when developing low-fat chocolate.
The combination of AMP, lecithin and PGPR will give out a full control of both yield value and plastic viscosity for fatreduced chocolates or any chocolate products.
Mono And Diglycerides
Typical table margarines have a fat content of 60-80 percent. The addition of monoglycerides contributes to the fine distribution of water droplets in the fat phase, ensures smooth spread consistency, stabilises the crystalline structure and forms a pleasant melt-in-the mouth sensation.
Blends of lecithin, mono and diglycerides can be incorporated into margarine and dairy spread applications as it could give these the required stability, texture and taste. Mono and diglycerides are normally added to margarine for emulsion stability or protection against weeping at levels below 0.5 percent.
Mono and diglycerides are also added into ice cream applications to de-emulsify some of the fat which helps to stabilise the air bubbles. The most commonly used emulsifiers in ice cream manufacturing are mono and diglycerides. They help to produce ice creams with desirable quality with improved overrun as well as the organoleptic attributes of the end product.
Common Food Stabilisers
Locust Bean Gum
Locust bean gum (LBG) is a natural plant-based derivative from the seeds of the carob tree cultivated in the Mediterranean region, North Africa, South Africa and Asia. There is a growing interest for LBG as it has shown to exhibit clean label properties and most importantly, it does not bring an aftertaste to flavour systems.
The strongest application of LBG is in its use as a thickening and stabilising agent in the food and beverage industries. It is frequently used in industrial applications due to its ability to form hydrogen bonds with water molecules.
LBG has the ability to act as a binder and stabiliser in processed meats, salami, bologna and sausages. It has a lubricating effect on the mix, which facilitates extruding and stuffing operations. It yields a more homogenous product with better texture and decreases weight loss during storage.
In soft cheese manufacturing on the other hand, LBG could help speed up coagulation, increase the yield of curd solids and in turn makes the curd easier to separate which results in better texture.
LGB exhibits a significant capacity to form synergistic interactions with other polysaccharides and enables the production of gelling characteristics for food and beverage applications. The most important synergies of LBG are observed when it is in contact with Xanthan Gum and Carrageenan for gelling properties.
Additionally, the ability of LGB to bind with water makes it an excellent choice for frozen applications such as ice cream. The gum slows down and reduces the size of ice-crystal formation as the moisture is retained within the ice cream.
h2]Gum Arabic [/h2]
Gum Arabic (GA) or also known as acacia gum is a natural gum that is extracted from the hardened sap of the acacia tree and is widely used by food and beverages formulators. GA has the ability to delay and prevent sugar crystallisation and to emulsify fat without affecting taste or viscosity of the end products. It is also added into powdered beverage mixes to produce the same opacity, appearance, mouth-feel and palatability as natural fruit juices.
In confectionery applications, GA is sometimes used as a glaze on candy products and as a component of chewing gum, cough drops and candy lozenges. In pastilles where sugar content is high and its moisture content is comparatively low, the incorporation of GA helps to prevent sugar crystallisation and keeps fats uniformly distributed throughout the product. In aerated confectionery products such as marshmallows, nougats, glace and meringues, GA exhibits favourable adhesive properties and acts as a whipping and stabilising agent.
In the food industry, GA is primarily used in confectionery, bakery, dairy, and beverage applications as an emulsifier as well as a microencapsulating agent. The emulsification properties of GA are also used in flavour emulsion beverages. Baking properties of wheat and rye flours can be improved by adding a small amount of GA due to its capacity for retaining moisture that reduces the hardening of bread.
For frozen products such as ice cream, GA is used as a stabiliser for its water absorption properties. GA enables fine texture and growth by inhibiting the formation of ice crystals. It combines a large amount of water keeping the product hydrated. Having a higher melting point is one of the main attractions of GA in ice cream applications.
Cellulose gum, a natural polysaccharide found in all plants, is a water-soluble gum that is based on cellulose. Cellulose gum is effective in increasing loaf volume and improving the quality of bakery products. In frozen pie fillings, the incorporation of cellulose gum decreases the amount of syneresis (release of moisture) upon thawing. It also retards sugar crystal growths in icings, frostings, glazings and toppings that contain high proportions of sugars. It is a useful stabiliser as it can retain water and retards the drying out of baked goods.
Cellulose gum aids in the stabilisation of reduced fat cookies during production in combination with other gums. Implementing a correct gum system will stabilise the ingredients and will produce crunchy, delicious cookies comparable to a full-fat version.
In confectionery products, cellulose gum helps in inhibiting sugar crystallisation in order to achieve the desired properties of gloss, body, mouthfeel, shelf-life and related textural attributes. Cellulose gum can also be added into meat analogue formulations. Grades with high water absorption will retain more moisture, leading to better eating qualities and moisture perception.
Cellulose gum is also an excellent stabiliser for low-pH dairy or protein beverages such as yoghurt drinks and acidified soy drinks as it stabilisers protein particles against sedimentation. It is also one of the leading stabilisers for ice cream and other frozen dairy foods.
Cellulose gum can form gels that lead to a reduction in oil absorption and increases moisture retention while reducing fat pickup for breaded fried products. Thus, cellulose gum can be combined with a reduced-fat substrate to achieve fat levels that meets low or reduced fat claims.
Consumer demand for more natural and ‘clean label’ formulations are steadily increasing. Global food industries are already on the lookout for ‘healthier alternatives’ for emulsifiers and stabilisers to fulfil consumers’ satisfaction and requirement.
Plant-based gums are suitable for vegetarians and gluten free formulations. They are virtually non-caloric, making them more suitable incorporations for reduced-calorie, fat-free and reduced fat formulated foods and beverages. They are widely used for their natural image and clean labelling in various food applications and can be used in combination to mimic functionalities and work synergistically.
The removal or reduction of trans fats has become a growing cause for concern among food and beverages manufacturers. Without trans fats, production processes become more sensitive to a variety of factors that have been comfortably handled by partially hydrogenated oils. However, by using the right blends of emulsifiers and stabilisers, it is possible to alleviate these problems and produce high quality end products for consumers.