Salt Production
Salt History
For centuries, salt had an important role in the global economy and a major influence on the culture of the people connected to it, contributing to commercial exchanges between countries. It is known that the Phoenicians used salt in fish salting, the Romans produced salt to an almost industrial scale and even paid their soldiers with salt (originating the word salary) and the Egyptians used salt to mummify the bodies. However, since the mid-twentieth century, with the change in the processes of conservation in rural areas and with the emergence of the industrial exploitation of this product, salt craft production started to decline, unable to compete in terms of prices with these units of high production and profitability. The current demand for products that are natural, local/regional and artisanal, the development of tourist activities in natural areas and the recognition of the importance of wetlands has driven to an increase of interest in traditional saltpans.
Forms of Exploitation The exploitation of sea salt can be developed using exclusively artisan means or mechanical means. Artisan The traditional saltpans, where salt is extracted only with hand tools, are saltpans with small crystallisers and salt can be collected on a daily basis, depending on the weather. Salt and fleur de sel collected by the traditional method do not undergo any transformation process, keeping the salts contained in seawater. The drying process is done in the saltpan, in heaps for a few days, depending on the weather conditions. In Portugal the production of salt by traditional method is developed in different geographical areas: Aveiro, Figueira da Foz, Alcochete, SetĂşbal, Alcacer do Sal, OlhĂŁo, Tavira and Castro Marim. Despite this geographic scale, the number of active saltpans is reduced.
Industrial/Mechanical The saltpans that produce salt with mechanical means, also called industrial saltpans, use big crystallizers (on average larger than 1000 m2), which allows the collection by bulldozers, winches and tractors, or specialized caterpillar machines, at the end of the season. The use of machinery introduces salt contamination factors (fuel and oil), which requires salt subsequent washing (sanitized or purified salt). In Portugal, the production of sea salt with the use of mechanical means is developed in Castro Marim and Tavira.
New Products New Uses
The traditional saltpans are places that allow the exploitation of a range of products and activities. Examples of new products, approaches and uses can be the following: ·· Fleur de sel (basic or flavoured) and flavoured salt used in cooking ·· edible halophytes such as Salicornia and Sarcocornia, are salty plants used in salads ·· seaweed (macroalgae and microalgae), with various uses ·· the microalgae Dunaliella salina, an algae rich in beta-carotene and a marker of origin, is used to feed fish, as a food supplement and in skincare cosmetics products ·· clays, used in health care and wellbeing, particularly for musculoskeletal pathologies and skincare cosmetics treatments ·· cosmetic products that incorporate salt or fleur de sel in its composition, as exfoliating creams or products made from salt, such as bath salts ·· tourist activities, such as ecotourism and ornithological tourism, activities related to health and wellbeing, such as hydrotherapy in saltpans – it is possible to develop these activities jointly with salt production This new approach already exists in Portugal, in some traditional saltpans, as well as elsewhere in the European Atlantic area.
The Salt from Aveiro
Chemical Characteristics Every salt contains a percentage of water. The salt from Aveiro comprises about 7% of water, which is lost as the salt is stored. A dry salt contains mainly sodium chloride (average values between 95% and 98%) and is composed of ions such as magnesium, calcium and potassium. The values for physicochemical, organoleptic and microbiological characteristics of the salt from Aveiro are within the values determined for table salt as it is referred to in the decree nº 72/2008, a legal document that establishes the legal framework of table salt.
Average values of the salt from Aveiro: ·· Moisture 7,1% ·· Sodium chloride 95,6% (dry salt) ·· Magnesium 0,47% ·· Potassium 0,13% ·· Calcium 0,13% ·· Sulphate 1,2% ·· Insoluble matter 0,20% ·· Nitrite < 0,1 ppm (mg/kg) ·· Nitrate < 1 ppm ·· Total metal pollutants 0-12ppm
Nutritional Value The salt from Aveiro, produced exclusively by artisanal methods, does not suffer transformation processes and maintains all its composition, which makes it a richer salt. In addition to sodium chloride, it contains other minerals essential for health such as magnesium, calcium, potassium; it contains no chemical additives and has a more intense aroma, which leads us to use less salt for the same use.
Curiosities The sensorial and volatile composition analysis of Aveiro salt identified some volatile and semi-volatile elements which validate the current assertion of the â&#x20AC;&#x153;Marnotosâ&#x20AC;? (saltpan workers) about the aroma of violets of the Aveiro salt and a fact which may have its origin in the algae of the environment surrounding the saltpans. There are compounds that are markers of sea salt and, therefore, are present in all these salts irrespective of its origin. However, the salt from salt is each saltpan is a unique salt, as a result of the surrounding environment. This specificity allows us to differentiate the salt from each saltpan, an important finding in getting markers of origin for the salt. An example of this differentiation was the result obtained in the characterization performed for the Aveiro salt; higher values of potassium and magnesium were determined for the Saltpan of Santiago da Fonte and 18 dos Caramonetes, when compared with the other saltpans in Aveiro.
The importance of salt for our organism Salt consists mainly of sodium chloride (chlorine ion and sodium ion). These two elements play distinct roles in the organism of living beings. Sodium ion ·· essential micronutrient for life and all cells ·· plays an active role in the absorption of other nutrients at the intestinal level ·· important regulator of water balance, the pH and osmotic pressure ·· plays an important role in the transmission of nerve impulses Chloride ion ·· essential in the performance of vital functions ·· formation of hydrochloric acid of the stomach ·· protects the acid/base balance ·· aids in the absorption of potassium ·· keeps kidneys functioning ·· increases the transport capacity of CO2 from the tissues to the lungs
The daily sodium needs vary with age, physical exertion and the loss through transpiration. The average adult requires 1.5 mg of sodium which corresponds to a daily intake of 4 g of salt. Nutritionally, salt is part of a healthy diet, provided that you respect the recommended daily dose.
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