Ettore Baglio – författare
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This Brief reviews the chemistry behind the production of yoghurt through acidification of milk. It quantifies the changes in physical and chemical properties of yoghurt during fermentation with microbial organisms (such as Lactobacillus bulgaricus and Streptococcus thermophilus). It has been found that this symbiosis has an optimal development at a temperature of ca. 45°C with the transformation of lactose into lactic acid and small amounts of acetaldehyde, diacetyl and volatile acids. This Brief explains the chemical and physical results of the fermentation process, such as precipitation of proteins and the acid coagulation of milk with a clot formation in the final semi-solid mass. The Brief sheds light on the accomplishments of the fermenting organisms: they are responsible for the biochemical reactions of carbohydrate metabolism, proteolysis, lipolysis and flavour production in the process of yoghurt production. It also briefly reviews formulations and food additives used in the modern yoghurt producing industry.
653 kr
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This Brief explains and discusses honey and its production from a chemical perspective. It outlines why honey is a special and unique food, being produced by bees from the nectar of plants or from secretions of living parts of plants. Although glucose and fructose are the main constituents of honey, its overall composition is far from being simple or uniform: other substances such as organic acids, enzymes, or minerals are found in varying amounts.
In this Brief, the author addresses the factors that influence the composition of the honey as well as the consequences that the composition has on properties such as color, crystallization, density, viscosity, or the refractive index. This Brief also introduces some of the most commonly used quality parameters for the determination of ageing and/or overheating: 5-hydroxymethylfurfural (HMF) and diastase. Other recently proposed constituents for quality parameters are also mentioned, e.g. 1,2 dicarbonyl compounds (3 deoxyglucosone,methylglyoxal, glyoxal) and furosine, also named 2-furoylmethyl lysine.