For a long time, mineral water has been available to the consumer as an alternative for tap water. Many consumers prefer using such water which is available from, inter alia, the supermarket in bottles or cartons.

Many mineral waters are offered in carbonated form, but non-carbonated variants are available too. According to the invention, the concept mineral water is understood to mean a mineralized drinking water or a drinking water which contains, usually an elevated amount of, minerals.

As a rule, the composition of mineral water differs from that of tap water. Mineral water contains a relatively higher concentration of dissolved salts than tap water. In addition, often, in mineral water, salts are present which are not found in tap water. Thanks to the presence of those salts, mineral water has the image of being a healthy product.

Mineral water is also often offered in dosing devices for, for instance, offices. As a rule, those devices contain a transparent storage reservoir for the water and a tapping location below which a glass or a mug can be placed. As a rule, known devices have two taps: one for water at room temperature and one for cooled water.

Offering mineral water via such dosing devices has different drawbacks. The storage reservoir also functions as refill package and is relatively heavy and, as a result, difficult to replace. As it is further important that the storage reservoir does not become empty too rapidly, it has a relatively large volume. This entails that, when relatively little mineral water is taken from the device, this water can age so that no fresh

mineral water is available. When the mineral water is to be stored too long, microbial contamination can occur, which cannot only be disadvantageous to the flavor of the water, but also to the health of the consumer.

In Dutch patent application 1019544, a device is proposed which does not have the drawbacks mentioned. This device generates mineral water from tap water, so that no relatively large storage reservoirs are required.

In the device, tap water is first filtered, preferably with the aid of reverse osmosis, so that a purified product is obtained containing virtually no other components than water. Any salts and/or microorganisms that may be present in the tap water are virtually entirely removed through reverse osmosis. After filtration, the water is brought to the desired composition by mixing it with a mineral concentrate.

As no use is made of large storage reservoirs, there is little risk of the mineral water needing to be stored in this device too long. Problems with freshness will not, or hardly, occur, not even when little or no mineral water is taken from the device for a longer period of time. The mineral concentrate itself is dosed in the device from a refill package. Due to the high concentration of minerals in the concentrate, refilling will be required less often than in the conventional devices in which a storage reservoir with ready product is to be replaced.

The present invention relates to a mineral concentrate which can be used for making mineral water from filtered tap water, for instance in the device described hereinabove, from Dutch patent application 1019544. A mineral water according to the invention has a particularly thought-out composition, so that, after mixing with filtered tap water in the correct ratio, a product is obtained which is, as to flavor and composition, very similar to mineral waters known to consumers. Furthermore, a mineral concentrate according to the invention has such a composition that the concentrate has a long shelf life without unacceptable risks of microbial contamination.

More specifically, the invention relates to a mineral concentrate with a total salt concentration of at least 5 g per liter, comprising: - from 0.1 to 273 g of calcium ions per liter, - from 0.1 to 200 g of magnesium ions per liter, - from 0.1 to 583 g of chloride ions per liter, and - from 0.1 to 276 g of sulfate ions per liter, in such mutual ratios, optionally complemented with other, optional ions, that an electrically neutral product is obtained.

The total salt concentration of a mineral concentrate according to the invention will depend on the nature and amount of the ions present in the concentrate. It is important that the solubility products of salts which can be formed through combinations of cations and anions present in the concentrate are not exceeded under the storage and processing conditions, so that no precipitation is formed. It has appeared that it is not possible to simply multiply the concentrations of ions present in known mineral waters by a certain factor of at least 100 in order to obtain a concentrate, because, then, certain salts will precipitate. Depending on the total composition of the concentrate, a skilled person will be able to select a suitable total salt concentration whereby, on the one hand, a product is obtained which can be processed to a mineral water in a simple manner, and, on the other hand, concentrations are achieved which are as high as possible in order that the concentrate takes up a volume which is as small as possible.

According to the invention, a mineral concentrate will contain at least 5 g of salts, and preferably at least 10 g of salts per liter. This concentration refers to the added mass of all cations and anions present, while the mass of any crystal water that may be present in the salts used for preparing the mineral concentrate is not included. With particular preference, the total salt concentration is over 20 g per liter, and more preferably in the range of 30 to 40 g per liter. In order to arrive at a desired mineral water, a mixing

ratio with filtered tap water of 25 to 500 liters of filtered tap water of mineral concentrate per liter is required.

A mineral concentrate according to the invention can be prepared by dissolving a selection of salts in water. Preferably, to this end, water is used which has been filtered in advance, preferably with the aid of reverse osmosis. Salts from which a selection can be made include NaCl, NHCO3, Na2CO3, Na2SO4, Na2SO4. 7H20, NaSiO3, Na3PO4, sodium lactate, CaCl2, Ca (HCO3) 2, CaS04. 2H20, CaSe04. 2H20, calcium lactate, calcium gluconate, MgCl2, Mg (HCO3) 2, MgSO4, magnesium gluconate, magnesium lactate, KCI, KHCO3, K2Mg (SO4) 2, K2Zn (SO4) 2. 6 H20, potassium gluconate, potassium lactate, ZnCl2, ZnS04, zinc gluconate, Si02, MnCl2, MnS04, manganese lactate, Ag2SO4, AgNO3, cobalt gluconate, FeS04. 7H20, FeCl2, FeCl3. 6Hz0, ferrous gluconate, ferrous lactate, and Li2CO3. The amounts and nature of the salts will be selected in view of the desired composition of the mineral concentrate. When selecting this composition, the recommended daily amount (RDA) of each mineral can be taken into account. Also, it can be decided to adapt amounts of certain minerals with regard to the target group of consumers of mineral water prepared with the mineral concentrate.

For instance, it may be advantageous for certain regions to include relatively large amounts of magnesium, zinc and/or manganese ions, to mitigate deficiencies in those minerals.

Preferably, calcium ions are present in a mineral concentrate according to the invention in a concentration up to 100 g per liter, more preferably from 1 to 10 and most preferably from 4 to 7 g per liter. These amounts of calcium ions in a mineral concentrate provide a mineral water with a good, neutral flavor which drinks easily.

Preferably, magnesium ions are present in a mineral concentrate according to the invention in a concentration up to 20 g per liter, more preferably from 0.5 to 5 and most preferably from 1 to 4 g per liter. These

amounts of magnesium ions in a mineral concentrate contribute to a somewhat bitter character of mineral water.

Preferably, chloride ions are present in a mineral concentrate according to the invention in a concentration up to 40 g per liter, more preferably from 5 to 30 and most preferably from 10 to 25 g per liter.

Preferably, sulfate ions are present in a mineral concentrate according to the invention in a concentration up to 240 g per liter, more preferably from 0.3 to 5 and most preferably from 0.8 to 3 g per liter. It has been found that these amounts of sulfate ions in a mineral concentrate may have a neutralizing effect on the too expressive flavor effects of cations present.

Preferably, also, one or more ions are present which have been selected from the group of sodium ions, potassium ions, zinc ions, manganese ions, and bicarbonate ions.

Preferably, sodium ions are present in a mineral concentrate according to the invention in a concentration up to 142 g per liter, more preferably from 0.1 to 60 and most preferably from 0.5 to 10 g per liter.

Preferably, potassium ions are present in a mineral concentrate according to the invention in a concentration up to 173 g per liter, more preferably from 0.1 to 60 and most preferably from 0.2 to 5 g per liter.

Preferably, zinc ions are present in a mineral concentrate according to the invention in a concentration up to 2072 g per liter, more preferably from 0.1 to 6 and most preferably from 0.3 to 2 g per liter.

Preferably, manganese ions are present in a mineral concentrate according to the invention in a concentration up to 350 g per liter, more preferably from 0.1 to 2 and most preferably from 0.2 to 1 g per liter.

Preferably, bicarbonate ions are present in a mineral concentrate according to the invention in a concentration of 0.1 to 240 and most preferably of 3 to 150 g per liter.

Other ions which may be present are iron (II), iron (III), cobalt, lithium, nitrate, carbonate, citrate, lactate, gluconate, phosphate, hydrogen phosphate, dihydrogen phosphate, silicate, hydrogen sulfate and the like.

Preferably, a mineral concentrate has a pH within the range of 1-5, more preferably 2-4. It has been found that, with such acidities, the shelf life of a mineral concentrate is considerably increased, while there is hardly any adverse effect or no adverse effect on the flavor of the mineral concentrate obtained after mixing the mineral concentrate with filtered tap water. In order to obtain the desired pH, use can be made of one or more of the following acids: phosphoric acid, hydrochloric acid, sulfuric acid, lactic acid, citric acid, ascorbic acid, malic acid, tartaric acid and acetic acid. In a preferred embodiment of the invention, the pH of the mineral concentrate is buffered around the desired pH. To this end, lactate, citrate or gluconate buffers may be used.

Other possible components of a mineral concentrate according to the invention are silicon dioxide, vitamins and the like.

In view of the neutral character of the product for the preparation of which a mineral concentrate according to the invention is intended, it is desirable that the mineral concentrate contains substantially no other components than the abovementioned and possible trace elements. Trace elements are understood to mean iron ions (II or III) iodide ions, chrome ions (II or IV), fluoride ions, cobalt ions (I or II), copper irons (I or II), molybdenum ions, selenium ions, tin ions (II or IV) or vanadium ions. The presence of carbohydrates, proteins and products derived therefrom will in any case be avoided.

It goes without saying that the mineral concentrate is not electrically charged, so that the concentrations of abovementioned ions, optionally together with the concentrations of other ions in the mineral concentrate, are to be selected such that, net, there is no electric charge.

The invention further relates to a method for preparing a mineral water in which tap water is filtered and mixed with a mineral concentrate as described hereinabove. The tap water is preferably filtered with the aid of reverse osmosis. The volume ratio between the amount of tap water and the amount of mineral concentrate is preferably between 25: 1 and 500: 1 and most preferably between 150: 1 and 300: 1. The mineral concentrate is, for instance, dosed from a refill package which has been sterilized before filling.

It is further preferred to pasteurize or to sterilize the mineral concentrate after preparation and before filling into the refill package.

A mineral concentrate according to the invention is, as said, particularly suitable for use in a device as described in Dutch patent application 1019544, in which mineral concentrate is prepared in situ. In the context of the invention, in situ preparation is understood to mean that the tap water is filtered and mixed with the mineral concentrate at the same location where the mineral concentrate prepared therewith is dosed and can be taken by a consumer.

The invention will now be further elucidated in and by the following example, which is not to be taken as being limitative.

Example The following salts were dissolved in the following amounts in 1000 liters of water which had been purified in advance with the aid of reverse osmosis (RO water < 20 uS). The salts were all of a quality acceptable for use in foods.

CaCl2. 2H20 20000 g MgCl2. 6H20 15000 g NaCl 4600 g KCl 800 g MgSO4. 7H20 3300 g H3PO4 267,75 g

The pH of the concentrate obtained was 3.0. The concentrate obtained was pasteurized and aseptically packaged in a refill package sterilized in advance.

From the obtained mineral concentrate, mineral water was prepared by purifying tap water with the aid of reverse osmosis (RO water < 20 uS) and mixing it with the mineral concentrate in a ratio of 200 liters of water mineral concentrate per liter. The water thus prepared has a very pleasant, neutral flavor which was very similar to commercially available mineral water.