Fried grain of couscous and preparation method thereof

Abstract

The present invention provides a method for producing, by means of frying, dry couscous which can further be rehydrated for final consumption very quickly and giving rise to couscous with high culinary quality (swelling, texture, firmness), which are not achieved with the current industrial process based on hot air drying. For this, the starting point is essentially water and semolina, preferably from durum wheat, as the main raw material, mixing and subjecting them to steam pre-cooking, but applying a process of frying to the pre-cooked grains instead of hot air for drying. The couscous grains obtained can be stored and marketed, needing only quick hydration in hot water to be consumed.

Description

[0001] FRIED GRAIN OF COUSCOUS AND PREPARATION METHOD THEREOF

[0002] TECHNICAL FIELD

[0003] The present invention falls within the field of cereal processing and agri-food technology. More specifically, the invention relates to a grain of fried couscous produced by an industrial process with double cooking which combines steaming and frying.

[0004] BACKGROUND OF THE INVENTION

[0005] The process of frying is a very ancient method of food preparation that is widely used throughout the world. It consists of submerging a food product in oil or fat heated to a temperature higher than the boiling point of water.

[0006] In documents about basic concepts of cooking (see, for instance, the Internet article by Danilo Alfaro “Basic Cooking Methods Dry Heat and Moist Heat Cooking”, the spruce eats, 29 March 2023, pages 1-7: https: / / www.thespruceeats.com / basic- cooking-methods-995429), frying can be found classified in the category of dry heat cooking because, contrary to the methods of moist heat cooking, even though fat can take a liquid form during frying, because the heat is transferred to the food without using any moisture (water), so that frying is considered “dry” heating. As mentioned before, Alfaro’s article mentions that dry-heat cooking typically involves high heat, with temperatures of 300eF (approximately 148,89eC) or hotter. Among the effects of dry heat cooking, Alfaro’s article mentions the browning of food, including Maillard reaction, which can only be achieved through dry-heat cooking.

[0007] The quality and stability of fried products depend on many factors, such as oil temperature, frying time, the ratio between the weight of the food and the volume of frying oil, but also the nature of the oils and foods to be fried.

[0008] Usually, partially hydrogenated oils, including palm, corn, cottonseed, soybean and sunflower oils, are the most widely used.

[0009] Palm oil in particular (understood as the oil obtained from the mesocarp or pulp of the fruit of oil palms) is one of the most used in the manufacture of food due, on one hand, to the ample supply available year-round, and also, to a large degree, because it is easy to stabilise and has no odour, which allows maintaining the aromatic quality and consistency of ultra-processed foods. Furthermore, it is a semi-solid oil at room temperature, which facilitates the workability of spreadable and / or extendable products, but is stable at high temperatures, thus helping to give fried products a crunchy texture and consistency. Unlike palm kernel oil (also known in Spanish as palmiste), its composition of saturated and unsaturated fatty acids is quite balanced (about 50%-50%), while in palm kernel oil the percentage of saturated fatty acids is about 81%.

[0010] In addition to palm oil as such, palm olein, which is the liquid fraction of palm oil, is also commonly used for industrial frying, and even in homes in tropical countries.

[0011] The composition of palm oil makes it not very susceptible to oxidation, even at high frying temperatures. This is mainly due to its low linolenic acid content and the presence of natural antioxidants, mainly tocopherols and tocotrienols. .

[0012] Although frying, as discussed above, is a process that is now applied to many foods, many foods of great importance in various cultures have traditionally been obtained by different methods of preparation. That is the case, for example, of the so-called couscous or kuskus (terms derived from the French name couscous, which seems to derive from the Berber term seksu). Couscous is a staple food in North African cuisine, traditional in the gastronomy of the Maghreb, the consumption of which has also spread throughout Europe and America. It is a dish the basic ingredient of which is generally durum wheat, although today other cereals can be used (barley, millet, rice or corn in the form of semolina or grains). In traditional cuisine, it is prepared using durum wheat (Triticum durum) semolina, in other words, durum wheat ground in such a way that it has not been converted into flour, but rather has larger sized granules, the mean diameter of which generally ranges between 130 pm (which would correspond to extra-fine semolina) and 700-1000 pm (which would correspond to coarse or granulated semolina). Wheat semolina is steam cooked with other ingredients, such as vegetables, chickpeas, red meat or chicken or only with milk. The traditional container to cook it is a couscoussier (from French), which consists of a pot in the upper part of which there is another smaller pot, the bottom of which has holes as if it were a strainer or steam basket and which is covered with a lid. In the lower part, for example, a meat stew with vegetables is prepared, while the couscous is prepared in the upper part with the steam rising from the lower part, which process takes several hours, until a sort of loose, vaporous pasta is obtained.

[0013] Currently, due to the limited time that people have to cook and also less space in the house, the traditional method of cooking couscous in a couscoussier has been replaced by the “quick” alternative of preparing couscous. This method of preparing couscous consists of boiling water with salt, pouring half of the water over the semolina, covering the semolina, letting it swell for 3 to 4 minutes, then adding the rest of the boiling water, letting it stand for 2 minutes and finally separating the grains with the help of a fork. To finish the dish, butter or another similar fat is added. This “quick” alternative to cooking traditional couscous entails a notable loss of quality in the final product, especially with respect to the curdling of the dough and the doughy texture that is obtained. This drop in quality may undoubtedly lead to a reduction in consumption over time and to a gradual replacement of couscous by alternatives such as basmati rice in the domestic diet. This is particular true when couscous preparation by the final consumer is carried out by using the commercially available couscous dry grains which have been prepared at the industrial level, which couscous grains need a final rehydration step by the final consumer to be edible.

[0014] At the industrial level, similarly to the traditional domestic process, the couscous preparation process uses preferably durum wheat semolina as raw material, although it is possible to use other cereals such as pearl millet, corn, soft wheat semolina and rice flour. As it can be seen in the scheme of Fig. 1 , the process has the main steps of. 1) agglomeration (which comprises the substeps of mixing, rolling and sieving, sifting or calibration), 2) cooking (steaming) and 3) drying (usually with hot air) and cooling, after which (or preferably after a subsequent size reclassification) dried coucous grains, ready to packaging and selling, is obtained.

[0015] In order to initiate the industrial process, drinking water is added to the semolina (or the alternative cereal) (1 ) in the first step in order to agglomerate it by begins with mixing with water, after which, preferably, the semolina is introduced into a drumshaped rotor in which grains or balls of raw couscous are formed. After a step of calibrating the grains or balls formed, they undergo a step of steam pre-cooking, in which starch gelatinisation takes place. At the end of this operation, the product obtained has a high moisture content, which is generally between 35% and 40%. To reduce this moisture content, in the current technological process of preparing current industrial dry couscous grains, this wet product is subjected to hot air drying in a dryer until it reaches a moisture content that is usually between 10% and 13% to obtain a good storage of the grain resulting from pre-cooking. This dry grain is couscous ready for commercial distribution, once sorted by size (the sifting, sieving or calibration substep) and packaged. It is commercialized either as bags or in sacks (containing, generally, from 250 grams to 25 kilograms) and has a shelf life of approximately 2 years.

[0016] By using the current industrial process of production of industrial dry grains of couscous, the different producers commercialize a product with very similar physicalchemical characteristics, particularly with regard to the humidity content, which ranges from 10% to 13%, more usually from 11.5% to 12.5%. Besides, the steam cooking and the drying have a strong influence in the end-properties of the product which is consumed at home after hydration, a process that does not modify substantially the properties of the starch granules obtained after the industrial processing, such as the degree of gelatinization.

[0017] The dry couscous grains obtained by the above described industrial process are those which are currently used in order to prepare couscous dishes at home and also as the starting foodstuff of most recipes for couscous dishes that can be found currently in Internet.

[0018] Analogously to other food products such as pasta, the dry industrial grains of couscous are not directly consumed, but they need a step of rehydration by means of hot water or steam. In fact, it can be said that industrial couscous grains do not need to cook, they just need to soak. As the cooking process by the final consumer is easy and quick, dry industrial couscous is also denominated “instant” couscous, as opposed to the cooking of raw traditional couscous, which requires hours. .

[0019] When the industrial dry grains of couscous that can be found currently in the market are subjected to the same rehydration process in order to prepare couscous dishes, the industrial couscous grains purchased from different producers show a similar behaviour, so that the values that can be measured for parameters associated to the level of culinary quality such as absorption time, swelling index and agglomeration index are also similar for the commercially available dry couscous grain products. Thus, it can be said that the field of manufacturing dry couscous grains is a very mature field where the currently used process allows scarce improvements with regard to the quality of the product and the differences depend mainly on the quality of the raw material and the culinary recipe used in the rehydration process carried out by the final consumer.

[0020] In fact, some recipes of couscous dishes propose to include the addition of fats (oils or butter) in the rehydration phase, with the aim of improving, in sensory terms, the quality of the final couscous dishes. Such fat stuffs can be added, for instance, in order to obtain firmer, looser and not sticky grains and / or other sensory improvements. Thus, for instance, the recipe available at Internet written by Suzy Karadsheh (Karadsheh Suzy, “How to Cook couscous Perfectly (Recipe & Tips)”, The Mediterranean Dish, 12 February 2024, pages 1-25, available at: https: / / www.themediterraneandish.com / how-to-cook-couscous / ) contains an optional step, where the couscous grains are heated in a little bit (about 1 to 2 tablespoon) of extra virgin olive oil, tossing around constantly, with the aim of making the couscous grains to gain a beautiful golden brown color, which is said to happen quickly. This optional step is denominated as toasting in the recipe and it is said to add great depth of flavor and a subtle nuttiness to the couscous. Even the subsequent step of rehydrating the couscous grains takes place in boiling water (or broth) where a small drizzle of extra virgin olive oil, and a pinch of kosher salt, have been added. Karadsheh’s recipe is designed to use as starting foodstuff Moroccan instant couscous, which is the one with smallest sized among commercial couscous grains, it is prepared from durum wheat semolina and has undergone the usual steps of steaming and drying during its industrial preparation process and, according to the recipe, is ready in the blink of an eye. Indeed, the recipe is expected to require about 15 minutes, 10 minutes being used to let the couscous grains to fully absorb the liquid. The yield of couscous ready to be consumed is said to be about 2 to 21 / 2 cups of cooked couscous per cup of dry couscous.

[0021] It would be interesting to find an alternative method of preparing industrial dry couscous that would allow maintaining or even improving the culinary quality parameters required by the final consumer, including the quickness of obtaining couscous ready to be consumed, without the need of adding fats during the domestic phase of rehydration. The present invention provides a solution to such problem.

[0022] DESCRIPTION OF THE INVENTION

[0023] The present invention provides a couscous preparation process which allows obtaining a marketable fried couscous with a quality similar (even superior) to that of the couscous currently obtained with the industrial dry grains of couscous currently available on the market and with a moisture content lower to said industrial dry couscous.

[0024] To this end, in the present invention and as summarised schematically in Fig 2, in the process of obtaining dry (marketable) couscous grains, the manufacturing / preparation process includes a step of frying, and preferably also a subsequent step of degreasing, which replaces the step of drying by hot air (and optionally also the subsequent cooling process) which are currently carried out in the industrial preparation of dry couscous grains.

[0025] This process including frying and degreasing allows obtaining an industrial product with significantly lower values of moisture content than those obtained with hot air drying, which are close to 12.5% (11.5-12.5%) and also a degree of starch gelatinisation clearly higher than the one obtained with the current production system of dry couscous, turning it into a product of higher quality. The couscous grains obtained by the process of the present invention only needs 5 minutes of hydration in hot water at 100°C to be consumed with the same, or even better, culinary quality parameters as that made with the current state of the art, so it can be called instant fried couscous.

[0026] The (sub)step of a second cooking by frying which includes the process of the present invention allows the elimination of the (sub)step of hot air drying, reaching lower moisture values of 8% weight / weight (w / w), even of 6% to be achieved, which values are not possible with the current process of the state of the art and guarantees a long preservation time. This is because, during the heating treatment by frying, the water in the couscous grains turns into steam and escapes, generating cavities in the couscous grains due to evaporation. However, furthermore, as can be seen particularly depicted in Fig. 3 and confirmed by the images of Fig. 4, the second cooking (sub)step (frying) allows to increase the degree of starch gelatinisation with regard to the degree obtained by drying with hot air. Besides, as shown in the Example section, water absorption during the rehydration process that allows to obtain edible couscous is higher than in the current industrial dry couscous grains, which an improved quality that will be appreciated by the consumers.

[0027] Additionally, by the degreasing step, with the grains still hot, the oil adhered to the couscous grain after cooking by frying is extracted by centrifugation.

[0028] Thus, the present invention relates to a method of preparing couscous grains wherein the step of drying is carried out by cooking in a food-grade oil (frying). As used herein, drying is understood to mean a process of reducing the moisture in couscous grains to a value of 13.5% weight / weight (which is the value that couscous should not exceed according to the Codex alimentarius: standard 202-1995) or lower, preferably equal to or less than 11.5%-12.5% weight / weight, and more preferably 6-8% weight / weight, which is the range that is typically obtained with the present invention, especially when the grains subjected to drying have an initial moisture of 35-45% weight / weight, and more particularly when the grains being dried are couscous grains that have undergone a process of steam pre-cooking prior to drying.

[0029] Although it can be considered that the scope of the method of the present invention encompasses the method of couscous preparation that comprises the final cooking step which is usually carried out at the domestic level, wherein the dry couscous is rehydrated in order to obtain the desired final couscous dish ready to be consumed, the method of the present invention is preferably defined as the preparation process of the marketable couscous product which is denominated as “dry couscous” or, in some cases, “instant couscous”, because it consists of dry couscous grains which can be consumed after rehydration, that is, balls or grains modelled from a ground cereal which have been subjected to a step of starch gelatinization by steaming and a subsequent step of drying for facilitating its storage and that also allows a quick final preparation process for the final consumer by rehydration (with water or with broths). For the purposes of the present invention, and as used along the present application, the term “dry couscous” or “dry couscous grains” relate to couscous grains with a moisture content equal or lower than 13% weight / weight (w / w). Thus, such a generic definition of “dry couscous” or “dry couscous grains” encompasses both the industrial dry couscous currently available in the market, which usually exhibits a moisture content of 10 % - 13%, particularly in the range of 11 .5% - 12.5%, and also the dry couscous grains prepared by the present invention, which exhibit even a lower moisture content. However, in some points of the present application, the term “industrial dry couscous” or “industrial dry couscous grains” is used only for the product obtained by the current industrial process, whereas the term “fried dry couscous” or “fried couscous grains” is used for the analogous product (although with better quality), obtained by the process of the present invention.

[0030] For purposes of the present invention, the terms “method of the present invention” and “procedure of the present invention” are considered equivalent and are used interchangeably at some points herein.

[0031] Thus, the method of the present invention, as it is schematically represented in Fig. 2, comprises the same basic steps as the current industrial process (schematically represented in Fig. 1), with the difference that the cooking step of the current industrial process is divided in two phases or substeps: a first substep of steam precooking and a second one of cooking by frying in hot oil which iis performed subsequently.

[0032] Therefore, in a preferred embodiment, the method of the present invention comprises the steps of : a) agglomeration, b) cooking, and c) degreasing.

[0033] Preferably, a) the agglomeration step comprises the substeps of a.1. mixing ground cereal with water, a.2. optionally modelling couscous grains by kneading and / or rolling or any other way of forming grains, and optionally a.3, calibrating and sieving the grains formed; b) the cooking step comprises the substeps of b.1. steam pre-cooking, b.2. drying by frying c) the degreasing step is carried out after frying without intermediate cooling.

[0034] Preferably, the degreasing is carried out by centrifugation.

[0035] Also preferably, sieving is carried out before storing and / or packaging. A conditioning step can be also be carried out before packaging. Furthermore, although it is not necessary with the method of the present invention, cooling can be carried out after degreasing if it is considered more suitable.

[0036] In order to obtain couscous ready to be consumed, it is sufficient to subjecting the fried couscous grains prepared by the method of the present invention to a final step of hydrating it in water (preferably hot water) or a broth for at least 5 minutes.

[0037] Furthermore, as discussed above, the couscous grains obtained by means of the procedure of the present invention have their own characteristics, in some of which they coincide with couscous grains prepared by the current industrial method (particularly, in the possibility of performing the final conditioning by means of a short treatment in hot water of 5 or 6 minutes, which allows it to be referred to, at some points of the present document, as instant fried couscous), while in others they are more similar to the granules obtained by the traditional method, particularly with regard to starch gelatinisation.

[0038] Based on the foregoing, another aspect of the invention is also a couscous grain product obtained by the method of the present invention, understanding as the method of the invention the embodiment which comprises the steps which give rise to the ready-to-market product, not yet subjected to hydration prior to consumption.

[0039] The main characteristic of said couscous grain product is the lower moisture content with regard to the analogous products that can be found currently in the market, obtained by the current industrial product with hot air drying. Thus, it is comprised in the present invention a couscous grain product which has a moisture content of 10% w / w or lower. Preferably, the moisture content is equal or lower to 8% w / w, for instance 6% - 8% w / w, but the method of the invention allows to obtain grains with a moisture content lower than 6% w / w, for instance of 5.80% w / w, which are also comprised in the scope of the present invention. In all cases, the moisture content is preferably calculated using the method used and set forth in the Example section of the present application, that is, the method wherein the moisture content (TH) is calculated by the following formula: T H%

[0040] Mo ~ Md wherein

[0041] MO : weight in g of a test portion of the grains of 5 g ± 1 g with the container where the test portion is dried (for instance a metal capsule with a diameter of 50 mm and a height of 28 mm with lid)

[0042] Md: weight in g of the empty container

[0043] M1 : weight in g of the test portion after having heated it in an oven for 2 hours ± 5 minutes at 130 to 133 °C it with the container opened, having removed the container from the oven, covered it and placed it inside a dryer, having allowed the container to cool to room temperature and having weighed the container with the test portion.

[0044] In a preferred embodiment, compatible with the previous ones, the couscous grain product is made with durum wheat semolina and has a mean size between 1600 pm and 850 pm, calculated as indicated in the Example section, that is, placing a 100 g sample on top of a series of sieves of mesh opening of 2000 pm, 1800 pm, 1600 pm, 1400 pm, 1250 pm, 1000 pm, 900 pm, 710 pm, 650 pm, arranged in decreasing order, making the device vibrate for 10 minutes, weighing the product retained in each sieve according to its grain size and classifying in its corresponding grain size group according to the maximum mesh opening size that particles pass through and, finally, expressing the weight in grams obtained in each sieve as a percentage. According to that methodology, a couscous grain product with a mean size between 1600 pm and 850 pm is a product that will have percentages higher than 0% in the size groups ranging from 1600 pm and 900 pm, but 0% in the groups of 1800 pm and 710 pm. More preferably, the highest percentages correspond to the groups of 1250 pm and 1000 pm, so that more than 50% of the grains have a mean size between 1250 pm and 1000 pm.

[0045] In another preferred embodiment, compatible with any of the previous ones, the grains of the couscous grain product contain palm oil or palm olein integrated in the grains. The present invention is explained below in greater detail by means of the drawings and the description of possible embodiments presented below.

[0046] BRIEF DESCRIPTION OF THE FIGURES

[0047] Fig. 1 shows the diagram of the current process for manufacturing dry couscous grains-

[0048] Fig. 2 shows the diagram of the process of the present invention for makingfried couscous grains.

[0049] Fig 3 schematically depicts the differences in the couscous grain obtained by means of the current process of hot air drying and the process of the invention that includes frying with a food-grade oil. Fig. 3a depicts the internal structure of the couscous grain, after steam pre-cooking (upper part) and after the next step, either hot air drying (left side) or frying with food-grade oil (right side). Fig. 3b outlines the development of the internal structure of the couscous grain in the final step of preparing according to the process of drying and the final cooking technique: Panel a): couscous grain dried by means of the current process (upper part) and subjected to rapid cooking in hot water (left part) or subjected to traditional cooking (40’ in couscoussier); Panel b): couscous grain dried by means of frying in oil before (upper part) and after (lower part) being subjected to hydration in hot water.

[0050] Fig. 4 shows photographs obtained with a microscope of couscous grains where, in the left hand images, granules of gelatinized starch have been outlined. Fig. 4a corresponds to grains of fried couscous according to the present invention; Fig. 4b corresponds to grains of industrial dry couscous prepared with the currently used manufacturing process.

[0051] DETAILED DESCRIPTION OF THE INVENTION: POSSIBLE EMBODIMENTS

[0052] As indicated above, the present invention relates to a method for obtaining couscous grains in which the step of air drying after steam pre-cooking consists of cooking in a food-grade oil, in other words, a process of frying. As discussed above, and as can be seen from the diagram of steps in Fig. 2, preferably the entire procedure can be carried out as a variant of the current industrial process, in which the step of hot air drying that currently takes place, is replaced by the process of frying in a food-grade oil. Therefore, by applying the method of the present invention, preferably the steps that would lead to obtaining a pre-cooked fried (dry) couscous grain product that could be considered “marketable” would be: a) agglomeration including mixing ground cereal and water and optionally calibrating the formed granules; b) cooking including steam pre-cooking and drying by means of a second cooking process (frying) in food-grade oil; c) degreasing preferably by centrifuging (for instance at 1000 - 2000 rpm, preferably at 1500 rpm); d) sieving; g) storing, optionally after packaging.

[0053] Thus, in the preferred embodiment of the method, the steps comprised in the method are those which allow obtaining fried couscous grains with a moisture content lower than that of the current dry couscous grains. Thus, the product obtained by the preferred embodiment of process of the present invention is different from the product obtained in recipes available in Internet such the one of Suzy Karadsheh already commented in the “Background of the invention” section, as the aim of said recipe is obtaining couscous ready to be consumed and the starting material for it is dry couscous grain acquired in the market, the current product which can be considered analogous regarding the intended use and the characteristics to the couscous grain product of the present invention, although the product of the present invention is of superior quality. But, even if the method of the present invention is considered as comprising also the step of rehydrating the fried (dry) couscous grains obtained by the method of the present invention, there are an important difference with regard to Karadsheh recipe which is the fact that, in that recipe, frying is used simply to toast couscous grains, not being indicated if said frying can have any influence in drying the product nor suggesting that said additional effect could happen, and also not indicating if that frying only for toasting induces a sealing process in the grains that protects the product from dehydration,.

[0054] The inclusion in the present invention of a step of frying for drying, replacing the drying by hot air that is currently used at the industrial level, is not suggested by the prior art, as can be seen in documents such as the Internet article by Danilo Alfaro whose content has been also commented in the “Background of the Invention” section, because such document describes frying as one of the methods of dry heating because no moisture (water or any other aqueous solution) is used, but it is not suggested or indicated that drying can be obtained by such process, but remarking the important effect of dry heat cooking in food browning, which is the effect sought by Karadsheh in her recipe. Moreover, Alfaro’s article mentions that dry-heat cooking typically involves high heat, what implies temperatures of 300eF (approximately 148,89eC) or higher, while the method of the present invention preferably works in the temperature range of 120eC to 150eC, the values around 135eC being preferred, what means that the present invention works in temperature values lower than those indicated by Alfaro.

[0055] For the procedure of the present invention, the starting ground cereal can be any of those used to prepare couscous, including rice, barley, millet or sorghum. The cereal is preferably selected from the group of durum wheat (Triticum durum), bread wheat (Triticum aestivum) or corn. Durum wheat, particularly in the form of semolina, which is what responds to the most traditional way of preparing the product, is particularly preferred.

[0056] The method of the present invention is compatible with the preparation of couscous grain products with a coarse, medium or fine size. Thus, with respect to the characteristics of the durum wheat semolina to be used, it is possible to use indications from the Codex Alimentarius, standard 202-1995: use a mixture of 20- 30% weight / weight of fine semolina (semolina with particles in which the largest diameter or width is between 130 and 183 pm) and 70-80% weight / weight of coarse semolina (particles in which the largest diameter or width has a value between 183 and 700 pm), which gives rise to couscous grains between 630 pm and 2000 pm. However, it is preferable to obtain medium-sized couscous grains; to that end, it is preferable to use semolina in which the particles pass through a sieve with a mesh opening of 500 pm, therefore having dimensions the largest width of which does not exceed 500 pm, but not less than 160 pm; alternatively, or complementary to the above, preferably the largest width or diameter of more than 50% of the semolina particles is between 300 pm and 500 pm. This produces couscous with a particle size (grains) between 1600 pm and 850 pm. In particular, by using durum wheat semolina with the indicated characteristics, the highest percentage of couscous grains will correspond to the grains retained by mesh size 1000, in other words, grains that are not retained by the 1250 mesh and fall through the 1000 dimension mesh, which can be considered grains with a maximum size of 1249 gm and a minimum size of 1000 gm.

[0057] With respect to the oil to be used in the step of drying by means of frying, it must be an authorised food-grade oil, preferably of plant origin. Any of the oils commonly used for preparing or dressing foods can be used (palm oil, sunflower oil, soybean oil, corn oil, olive oil, rapeseed oil, palm olein, etc.). Frying preferably takes place at a temperature of 120°C to 180°C and for 2 to 8 minutes, a shorter time being necessary if the temperature is higher. The preferred temperature range allows the oil to use to be selected from, among others, the group of palm oil, sunflower oil, soybean oil, corn oil and palm olein.

[0058] There is a preference for the use of palm oil or palm olein, preheated to a temperature between 120°C and 150°C (with a special preference for the value of 135°C), and for a frying time of 2 to 5 minutes (preferably 3 minutes).

[0059] The couscous grain product obtained by the method of the present invention exhibit specific features, which makes it to be included in the scope of the present invention, as commented in the “Summary of the invention”, being particularly remarkable the lower moisture content that can be obtained by the method of the present invention.

[0060] Thus, comprised in the invention is a couscous grain product having a moisture content equal or lower than 10% w / w, preferably of 6% -8% w / w, being possible to obtain even product with moisture content lower than 6%, as can be seen in the Examples section.

[0061] The preferred embodiment of the couscous grain product of the present invention relates to medium-sized couscous grains (between 1600 pm and 850 pm) more preferably where the majority of the couscous grains have a maximum size of 1000 pm and a minimum size of 900 pm are preferred, as described in Table 2 of Example 1 described below. It is particularly preferred that the couscous grains are produced with durum wheat semolina and fried in palm oil or palm olein, which will have oil integrated in the grain structure. With respect to the method of the invention, the preferred embodiment is one that gives rise to a couscous grain product with the characteristics indicated above, particularly frying in palm oil or palm olein preheated to 135°C and a frying time of 3 minutes (or even simply 2.85 minutes). The Example presented below illustrates a possible preferred embodiment of the present invention.

[0062] EXAMPLE

[0063] Preparation of 1000 kg of industrial fried couscous (IFC).

[0064] 1. Starting materials a. Durum wheat semolina: 1440 g to obtain 1200 g of pre-cooked couscous grains and 1000 g of instant fried couscous.

[0065] Characteristics of starting semolina:

[0066] Particle size:

[0067] Table 1

[0068] * Maximum mesh opening size that particles pass through

[0069] Protein content: 11% - 15% weight / weight

[0070] Moisture: 14.5%-15.5% weight / weight b. Water: 350 ml of mineral water for human consumption for the agglomeration step. c. Vegetable oil: 15000 ml (15 litres) of palm olein for cooking .

[0071] 2. Process of preparing industrial fried couscous

[0072] The three steps of the industrial process were carried out with the starting material, namely.

[0073] Agglomeration: This step begins with mixing with water, after which the semolina was introduced into a drum-shaped rotor in which grains or balls of raw couscous are formed.

[0074] Cooking: Couscous grains or balls were subjected to a first step of steam precooking, whereby 1200 g of product was obtained, with a moisture content in the range from 35% to 40%. This product was introduced into an industrial fryer (Induction Fryer 30 L - 60 to 190 °C - Royal Catering Model RCIN - 700 - 2) with 5 litres of palm olein. The oil was heated to a temperature above 120°C and below 150°C (preferably 135°C) for a minimum period in the range from 2 minutes to 5 minutes (preferably 3 minutes) with the aim of finalizing the industrial cooking by frying.

[0075] Degreasing: The just fried and still hot couscous grains were introduced into a centrifuge for degreasing them at a speed of 1 ,500 rpm for a period of 3 minutes.

[0076] 3. Results obtained

[0077] At the end of the process 1000 g of fried couscous, ready to pack, are obtained, with the following characteristics:

[0078] 3.1. Granulometry

[0079] In order to determine the granulometry, the following materials and methodologies were used:

[0080] Material:

[0081] Analytical balance with a precision of 0.1 gr

[0082] RETSCH laboratory sieve (model AS 200 basic) equipped with Series of circular stainless steel sieves with bottom, lid;

[0083] Diameter 223 mm,

[0084] Mesh opening: 2000 pm, 1800 pm, 1600 pm, 1400 pm, 1250 pm, 1000 pm, 900 pm, 710 pm, 650 pm

[0085] Procedure:

[0086] Take a 100 g sample.

[0087] The sample is placed on top of a series of sieves arranged in decreasing order. Under the vibrating effect of the device for 10 minutes, the different grain sizes are retained in the corresponding sieve.

[0088] The product retained in each sieve is weighed and classified according to the mesh opening.

[0089] Expression of results

[0090] The result is the weight in grams obtained in each sieve expressed as a percentage. The couscous obtained presented grains with the following size distribution:

[0091] Table 2: Couscous percentage size*

[0092] * Maximum mesh opening size that particles pass through

[0093] 3.2. Moisture content

[0094] Material

[0095] Analytical balance to ± 0.001 gr

[0096] Metal capsules with a diameter of 50 mm and a height of 28 mm with lid

[0097] Adjustable isothermal oven to keep the temperature between 130-133°C for 2h,

[0098] Dryer containing an effective drying agent (silica gel)

[0099] Metal tweezers and spatula.

[0100] Procedure

[0101] Perform two tests on the same sample, weigh them to 0.001 gr.

[0102] The capsules and their lids must be dried and weighed: register Md.

[0103] Tare and weigh a test portion to 5 g ± 1 g: register M0.

[0104] Place the opened capsules + lid in the oven and leave for 2 hours ± 5 minutes at 130 to 133 °C.

[0105] When the indicated time is up, quickly remove the capsules from the oven, quickly cover and place inside the dryer.

[0106] Allow to cool to room temperature and weigh the capsules to obtain M1

[0107] Expression of results:

[0108] Moisture content expressed as a percentage:

[0109] Mi - Md

[0110] T H% = (1 ) X 100

[0111] Mo ~ Md

[0112] M0 : weight in g of the test portion with capsule

[0113] Md: weight in g of the empty capsule M1 : weight in g of the test portion after drying with capsule

[0114] The moisture content of the obtained couscous grains were in the range of 5.80% - 6.90% weight / weight

[0115] The results obtained were different depending on the frying time (FT) and the oil temperature, as can be seen in the Table below. Additionally, it was found that the yellow color of the grains was more homogeneous by frying 3 minutes at 135eC in palm olein or palm oil, so that those are particularly preferred conditions for carrying out the method of the present invention:

[0116] Table 2: Moisture content according to the frying conditions

[0117] 3.3. Size of particles of gelatinized starch

[0118] Gelatinization is an irreversible structural change of starch during thermal impact , which is difficult to determine by using physical analytical methods. In the present case, information about gelatinization was obtained by taking images of the couscous grains by means of a digital microscope (OPTIKA MODELO B-290 TB). Representative examples of said images can be found in Fig. 4. In accordance to said images, it can be said that starch gelatinization reaches an average dimension of 15,72 micrometres in the grains of fried couscous of the present invention, clearly greater than the 10.02 micrometres of average dimension in starch granules that can be in dry couscous grains obtained by the current industrial process.

[0119] 3.4. Comparison between regular couscous and instant fried couscous during the drying phase (dehydration)

[0120] As discussed above, the normal couscous preparation time is 50 min, while the fried couscous preparation time is 25— 30 min, so instant fried couscous saves 25 to 30 min of time. This is due to the shorter duration of the step of drying. Furthermore, the moisture percentage achieved with instant fried couscous is even lower. Table 3: Dehydration

[0121] 3.5. Culinary quality of couscous

[0122] The culinary quality of couscous corresponds to how it behaves during and after cooking. azs<

[0123] The purpose of cooking couscous is to gelatinise the starch to make it hydrophilic, to modify the texture appearance of the couscous.

[0124] Culinary quality of couscous is measured from the following parameters:

[0125] • Rehydration velocitv / rate: The purpose of the rehydration rate is to evaluate the period at the end of which the couscous is edible after its rehydration. The faster the rehydration, the better the quality of the couscous grain. It is evaluated by mixing the dry couscous grains and water and measuring the time needed for the grains to absorb the water and become edible.

[0126] • Swelling index: This corresponds to the ability of the grains to increase in volume during the rehydration process. It is assumed that high swelling indices correspond to high quality couscous.

[0127] • Texture property: This refers to firmness, stickiness and chewability of couscous after cooking. They can be determined qualitatively by means of organoleptic analysis. Good culinary quality couscous can be broken up with a fork after rehydration and should remain firm but not too hard and not showing agglomerates.

[0128] Said quality parameters were measured in dry regular industrial couscous and the fried couscous of the present invention. The procedures used and the values obtained are detailed below: .1 . Swelling index

[0129] Material

[0130] 2 x 250 ml graduated cylinders with a precision of 2 ml, with an internal diameter between 35 and 42 mm.

[0131] Stopwatch accurate to the second.

[0132] Balance with a precision of 0.1 g.

[0133] Thermometer accurate to 0.5 °C.

[0134] Stirring rod made of glass or plastic or stainless steel with a diameter of about 6 mm and a length greater than 10 cm from the height of the cylinder Procedure

[0135] Weigh 50 g ± 0.5 g of couscous to empty by gravity into the first graduated cylinder.

[0136] Record V1 as the value of the volume occupied by the sample to be expressed with a precision of 2 mL or more.

[0137] Fill the second cylinder with 200 ml ± 1 ml of tap water at a temperature of 20 °C ± 2 °C.

[0138] Empty the 50g of couscous grain from the first cylinder completely into the second cylinder with the water

[0139] Stir two or three times with the stirring rod, making sure that there are no couscous grains floating around, and start the stopwatch at the same time.

[0140] After 30 minutes, take the volume V2 to express it to the nearest 2 ml occupied by the couscous grain in the test tube.

[0141] Make a minimum of two determinations for the test.

[0142] Expression of results

[0143] The result, or Volume Increase Index (VI), is expressed as follows:

[0144] IV = V2 / V1

[0145] It will be expressed to 2 decimal places

[0146] The difference between the results of two IV determinations performed simultaneously or quickly, one after the other, by the same analyst, will not exceed 5 percent. In this case, the result is the arithmetic mean expressed to two decimal places p. If not, repeat the test.

[0147] The Table below shows the results obtained in 3 subsequent assays for calculating the swelling index in 30eC in cold water (20eC): Table 4: Comparison of swelling . Rehydration rate / velocity

[0148] Material

[0149] 125 ml Pyrex graduated cylinder with a precision of 1 ml.

[0150] Pyrex crystallizer with a diameter of 145 mm and a height of 70 mm.

[0151] Metal fork .

[0152] Stopwatch accurate to the second.

[0153] Balance with a precision of up to 0.1 g

[0154] Process

[0155] Weigh 100 g ± 1 g of couscous grain.

[0156] Pour 100 ml ± 1 ml of boiling water without salt (tap water) measured with a test tube into the crystallizer.

[0157] Pour the 100 g of previously weighed couscous over the water contained in the crystallizer

[0158] Stir for a few moments with a fork to obtain a homogeneous rehydration and to avoid the formation of lumps.

[0159] Allow to hydrate without stirring for 3 minutes ± 10 seconds measured with the stopwatch.

[0160] Stir again for a few moments, let stand for 2 minutes ± 10 seconds and test the couscous as specified below.

[0161] At the end of these 5 minutes, and every minute ± 10 seconds, if necessary, test the couscous until the grains do not break when bitten, are tender and separate easily with the fork without the presence of lumps.

[0162] Perform at least two consecutive determinations for the test.

[0163] Expression of results

[0164] The rehydration rate is the arithmetic mean expressed in minutes, rounded to the nearest 30 s of the minute of the two determinations. The difference between the results of two determinations made simultaneously or quickly, one after the other, by the same analyst, must not exceed 1 min (otherwise the test must be repeated). The results obtained, as well as those related to the test of texture property performed manually with the aid of a fork at naked eye are shown in Table 5 below, where the average value of volume increase has been included in order to facilitate the comparison of culinary parameters.

[0165] Table 5: Comparison of parameters of culinary quality

Claims

CLAIMS1. A method of preparing couscous grains, characterised in that it comprises a step of drying following steam pre-cooking wherein the drying is carried out by means of frying in a food-grade oil.

2. The method according to claim 1 , wherein the couscous grains are dry grains.

3. The method according to claim 2, comprising the steps of: a) agglomeration, b) cooking, and c) degreasing-4. The method according to claim 3, wherein a) the agglomeration step comprises the substeps of a.

1. mixing ground cereal with water, a.

2. optionally modelling couscous grains by kneading and / or rolling or any other way of forming grains, and optionally a.3, calibrating and sieving the granules formed; b) the cooking step comprises the substeps of b.

1. steam pre-cooking, b.

2. drying by frying; c) the degreasing step is carried out after frying without intermediate cooling.

5. The method according to claim 3 or 4, wherein i. degreasing is carried out by centrifuging; ii. a step of cooling is optionally carried out after degreasing; and / or ill. sieving is carried out before storing and / or packaging, and / or iv. conditioning is carried out before packaging.

6. The method according to any one of the preceding claims, wherein the ground cereal is selected from the group of durum wheat, bread wheat and corn.

7. The method according to claim 6, wherein the ground cereal is durum wheat in the form of semolina8. The method according to claim 7, wherein more than 50% of the semolina particles have a diameter comprised between 300 pm and 500 pm.

9. The method according to any one of the preceding claims, wherein the drying by means of frying in a food-grade oil is carried out at a temperature of 120°C to 180°C and for 2 to 8 minutes.

10. The method according to claim 9, wherein the food-grade oil is selected from the group of palm oil, palm olein, sunflower oil, soybean oil and corn oil.

11. The method according to claim 10, wherein the step of drying by means of frying in a food-grade oil is carried out: i) at a temperature between 120°C and 150°C, ii) for 2 to 5 minutes, and iii) in a food-grade oil that is palm oil or palm olein.

12. The method according to claim 11 , wherein the step of drying by means of frying in a food-grade oil is carried out: iv) at a temperature of 135eC , v) for 3 minutes, and vi) in a food-grade oil that is palm oil or palm olein.

13. The method according to any one of claims 3 to 13, wherein in the step of sieving, couscous grains with a maximum size of 3150 pm are selected, .wherein the grain size has been determined by placing a 100 g sample on top of a series of sieves of mesh opening of 2000 pm, 1800 pm, 1600 pm, 1400 pm, 1250 pm, 1000 pm, 900 pm, 710 pm, 650 pm, arranged in decreasing order, making the device vibrate for 10 minutes, weighing the product retained in each sieve according to its grain size and classifying in its corresponding grain size group according to the maximum meshopening size that particles pass through and, finally, expressing the weight in grams obtained in each sieve as a percentage14. A couscous grain product characterized by having a moisture content equal or lower than 10% w / w.

15. The couscous grain product according to claim 14, which has a moisture content of 6% - 8% w / w.

16. The couscous grain product according to claim 14 or 15, wherein the moisture content has been calculated by the formula:M i - MdT H% = (1 - ) X 100Mo - d whereinMO : weight in g of a test portion of the grains of 5 g ± 1 g with the container where the test portion is driedMd: weight in g of the empty containerM1 : weight in g of the test portion after having heated it in an oven for 2 hours ± 5 minutes at 130 to 133 °C it with the container opened, having removed the container from the oven, covered it and placed it inside a dryer, having allowed the container to cool to room temperature and having weighed the container with the test portion.

17. The couscous grain product according to any one of claims 14 to 16, wherein the couscous grain product is made of durum wheat semolina and has a mean size between 1600 pm and 850 pm.

18. The couscous grain product according to claim 17, wherein more than 50% of the grains have a mean size between 1250 pm and 1000 pm.

19. The couscous grain product according to claim 17 or 18, wherein the grain size has been determined by placing a 100 g sample on top of a series of sieves of mesh opening of 2000 pm, 1800 pm, 1600 pm, 1400 pm, 1250 pm, 1000 pm, 900 pm, 710 pm, 650 pm, arranged in decreasing order, making the device vibrate for 10 minutes, weighing the product retained in each sieve according to its grain size and classifying in its corresponding grain size group according to the maximum mesh opening size that particles pass through and, finally, expressing the weight in grams obtained in each sieve as a percentage.

20. The couscous grain product according to any one of claims 14 to 19, wherein the grains contain oil integrated in the grain.

21. The couscous grain product according to any one of claims 14 to 20, which has been obtained according to the method of any one of the claims 2 to 13.

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