Rising ambition
Consumers in industrialised countries are increasingly looking for products that are low in fat, sugar and sodium and high in fibre, vitamins and minerals. But above all they are looking for products that are perceived to be healthy and natural, free from artificial preservatives, colours and flavours, and minimally processed. As a result, natural and organic products have therefore become one of the most dynamic areas of the food industry.Key to the success of these products is the perception that they are more healthy and wholesome than conventionally produced foods, although such claims are actually not that easy to substantiate scientifically.
Today, organic and natural trends affect all food categories. According to the European Commission, the organic market is growing by 10-15% a year, which is five times faster than the general food market. For example, in 2005, product launches in the bakery sector with the claim "all natural" or "organic" comprised around 5% of launches in the EU. In 2008 they will most likely account for 10% of launches, moving out from the niche in to the mainstream.
What is Glucono-delta-Lactone?
Glucono-delta-lactone (GdL) is obtained by crystalisation of gluconic acid, a so-called fruit acid. Gluconic acid is naturally occurring in plants, fruits and other foodstuffs such as wine (up to 0.5%) and honey (up to 1%). Jungbunzlauer's gluconic acid and GdL are produced by microbial fermentation of a natural and renewable carbohydrate source.
When put in contact with water, GdL dissolves immediately, but hydrolyses only progressively to gluconic acid, leading to a controlled decrease of pH while taste changes from slightly sweet to mildly acidic. As the hydrolysis kinetics of GdL are temperature dependent, acidification can be slowed down or speeded up via temperature control.
Is it natural?
In Europe, GdL is a generally permitted food additive. It may be added to all foodstuffs, following the "quantum satis" principle. In the US, GdL has been assigned GRAS (generally recognised as safe) status and its use in food is permitted without limitation other than current GMP (good manufacturing practice).
In the US, GdL also belongs to the non-synthetic non-agricultural (non-organic) substances allowed as ingredients in or on processed products labelled as organic or "made with specified organic ingredients"
However, there is still no valid legal definition for the term 'natural'. Therefore, it is somewhat subjective and open to individual interpretation. Nevertheless, Jungbunzlauer considers its GdL as natural because:
• its dissolved form, gluconic acid, occurs in natural foods such as wine and honey
• it is based on natural carbohydrates as raw materials
• it is made by a natural process (microbial fermentation).
Leavening agents
Non-yeast leavening systems are presently used in a wide range of bakery products, both conventional and organic/natural. These systems involve the action of one or more leavening acids on sodium and other bicarbonates to release carbon dioxide gas for aeration of a dough or batter during mixing and baking. Leavening acids can be classified based on their neutralising capacity and their release characteristics.
The neutralising value represents the parts by weight of sodium bicarbonate that can be neutralised by 100 parts by weight of leavening acid. This enables you to compare the available acidity of various leavening agents and to determine the correct level of use of acid to produce a neutral pH. It is usually wished that acid and bicarbonate react completely to avoid soapy or acidic taste profiles or undesirable changes in colour and texture.
In the case of GdL, 1g is needed to neutralise 0.472g of sodium bicarbonate. GdL does not react with sodium bicarbonate in the dry state, making blends of the two shelf-stable. When water is added, GdL and sodium bicarbonate quickly dissolve. Subsequently, GdL progressively hydrolyses to gluconic acid, which then reacts with sodium bicarbonate, providing a slow, continuous release of carbon dioxide over time.
The dough rate of reaction (DRR) specifies the timing and rate at which carbon dioxide is released. GdL is considered as a time-delayed agent with a well-controlled release of carbon dioxide over time, accelerated by increased temperature.
GdL's benefits
As temperature control enables you to slow down or speed up the conversion of GdL to gluconic acid and thus the rate of carbon dioxide release, this sole ingredient can substitute several types of phosphates from fast ones to very slow ones. This versatility makes GdL much appreciated in multi-purpose baking mixes. At the opposite end, the possibility of fine-tuning the rate of release by controlling the temperature allows the use of GdL in high-tech canned refrigerated dough products.
With its typical mild taste, GdL allows the true natural flavour of the baked goods to come through, while the typical off-notes such as bitterness and soapiness caused by the use of pyrophosphates do not occur when using GdL in cakes and muffins.
The crumb and crust properties of baked goods can also be improved with GdL, which creates a lighter crumb colour and a more homogeneous cell structure. Thanks to well-controlled and heat-accelerated gas release, products with high volumes are also possible. Gluconates buffer at a lower pH level than phosphates, so overdosing GdL allows the baked goods to acidify. Shelf-life can thus be prolonged in a natural way without negative effects on taste as gluconic acid has a mild flavour.
Sodium reduction
Western consumers currently eat 3-5g of sodium (equivalent to 7.5-12.5g of salt) per day, well over the daily upper limit of 2.4g and 2.3g recommended by the UK Food Standards Agency and US Dietary Guidelines, respectively, in order to avoid hypertension, cardiovascular diseases and stroke.
In bakery products, more than 95% of the sodium comes from three sources: salt, sodium bicarbonate and leavening acid. Salt is not easy to replace due to its taste and technological benefits. Sodium bicarbonate may be replaced by potassium bicarbonate but due to its cost and taste this is not a real alternative.
When replacing sodium acid pyrophosphate (SAPP) with GdL, a sodium reduction of 25-35% can be achieved in muffins and cakes while keeping product quality. GdL can thus significantly contribute to the sodium reduction in such products and enables bakers to label them with the nutrition claims: "reduced sodium" or "light in sodium" under the EU Nutrition and Health Claims Regulation.
Aluminium reduction
In 2006, JECFA (Joint FAO/WHO Expert Committee on Food Additives) made a new toxicological evaluation of aluminium. It concluded that aluminium compounds have the potential to affect the reproductive system and developing nervous system at doses lower than those used in establishing the previous PTWI (Provisional Tolerable Weekly Intake) of 7mg/kg body weight. Thus it revised aluminium's PTWI down to 1 mg/kg body weight. The EFSA (European Food Safety Authority) recently aligned with JECFA.
While the use of SALP (Sodium Aluminium Phosphate, Acidic) is not as widespread in Europe as in the US, it is considered as the leavening acid of choice in muffins, sponges and scones, especially in the UK. According to users, its main benefits are: providing a better taste in baked goods (compared to SAPP), an appealing product appearance (lightness and texture) and a better mouthfeel.
As GdL obviously does the same, bakers can reduce the aluminium content of their products by the concentration originating from SALP.
Phosphates do not meet users' needs
GdL has been known for decades as a high-quality leavening acid with uses limited to specific bakery products. But the demand for organic and all natural baked goods is now exploding and phosphates cannot meet users' needs, being either not allowed (SALP in US organic bakery products) or questioned about their naturalness.
Also the need of individuals to reduce sodium and aluminium intake while keeping product quality speaks in favour of GdL. Indeed, its unique combination of technological, legal, nutritional and economical benefits makes GdL more interesting than ever as a natural leavening acid, especially for muffins, cakes and pancakes in their organic, natural, sodium-reduced, aluminium-reduced and gluten-free forms.
Jungbunzlauer International is a leading supplier of citrates, special salts, sweeteners, gluconates and xanthan gum.
Tel: +41 61 2955 100 http://www.jungbunzlauer.com
