Milk Chocolate Digestives

Gold is a chemical element with symbol Au (from Latin: aurum) and atomic number 79, making it one of the higher atomic number elements that occur naturally. In its purest form, it is a bright, slightly reddish yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal and a group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions. Gold often occurs in free elemental (native) form, as nuggets or grains, in rocks, in veins, and in alluvial deposits. It occurs in a solid solution series with the native element silver (as electrum) and also naturally alloyed with copper and palladium. Less commonly, it occurs in minerals as gold compounds, often with tellurium (gold tellurides). Gold is resistant to most acids, though it does dissolve in aqua regia, a mixture of nitric acid and hydrochloric acid, which forms a soluble tetrachloroaurate anion. Gold is insoluble in nitric acid, which dissolves silver and base metals, a property that has long been used to refine gold and to confirm the presence of gold in metallic objects, giving rise to the term acid test. Gold also dissolves in alkaline solutions of cyanide, which are used in mining and electroplating. Gold dissolves in mercury, forming amalgam alloys, but this is not a chemical reaction. A relatively rare element, gold is a precious metal that has been used for coinage, jewelry, and other arts throughout recorded history. In the past, a gold standard was often implemented as a monetary policy, but gold coins ceased to be minted as a circulating currency in the 1930s, and the world gold standard was abandoned for a fiat currency system after 1971. A total of 186,700 tonnes of gold exists above ground, as of 2015. The world consumption of new gold produced is about 50% in jewelry, 40% in investments, and 10% in industry. Gold's high malleability, ductility, resistance to corrosion and most other chemical reactions, and conductivity of electricity have led to its continued use in corrosion resistant electrical connectors in all types of computerized devices (its chief industrial use). Gold is also used in infrared shielding, colored-glass production, gold leafing, and tooth restoration. Certain gold salts are still used as anti-inflammatories in medicine. As of 2016, the world's largest gold producer by far was China with 450 tonnes per year.

MALIC ACID is an organic compound with the molecular formula C4H6O5. Malic acid has two stereoisomeric forms (L- and D-enantiomers), though only the L-isomer exists naturally.

Polyglycerol polyricinoleate (PGPR), E476, is an emulsifier made from glycerol and fatty acids (usually from castor bean, but also from soybean oil). In chocolate, compound chocolate and similar coatings, PGPR is mainly used with another substance like lecithin to reduce viscosity. It is used at low levels (below 0.5%), and works by decreasing the friction between the solid particles (e.g. cacao, sugar, milk) in molten chocolate, reducing the yield stress so that it flows more easily, approaching the behaviour of a Newtonian fluid. It can also be used as an emulsifier in spreads and in salad dressings, or to improve the texture of baked goods. It is made up of a short chain of glycerol molecules connected by ether bonds, with ricinoleic acid side chains connected by ester bonds. PGPR is a yellowish, viscous liquid, and is strongly lipophilic: it is soluble in fats and oils and insoluble in water and ethanol.

Sodium carbonates (E500) are compounds commonly used in food preparation as leavening agents, helping baked goods rise by releasing carbon dioxide when they interact with acids.

Often found in baking soda, they regulate the pH of food, preventing it from becoming too acidic or too alkaline. In the culinary world, sodium carbonates can also enhance the texture and structure of foods, such as noodles, by modifying the gluten network.

Generally recognized as safe, sodium carbonates are non-toxic when consumed in typical amounts found in food.

Sodium hydrogen carbonate, also known as E500ii, is a food additive commonly used as a leavening agent.

When added to recipes, it releases carbon dioxide gas upon exposure to heat or acids, causing dough to rise and resulting in a light, fluffy texture in baked goods.

It is generally recognized as safe (GRAS) by regulatory authorities when used in appropriate quantities and poses no significant health risks when consumed in typical food applications.

AMMONIUM BICARBONATE is an inorganic compound with formula (NH4)HCO3, simplified to NH5CO3. Ammonium bicarbonate is used in the food industry as a raising agent for flat baked goods, such as cookies and crackers, and in China in steamed buns and Chinese almond cookies. It was commonly used in the home before modern day baking powder was made available.