Method and apparatus for obtaining food products from hard wheat and products obtained thereby

Abstract

The present invention relates to a method for obtaining hard wheat oil, further degreased coarse flour and hard wheat lecithin starting from hard wheat. The invention also relates to a method for obtaining a flour product of defatted hard wheat germ and defatted hard wheat bran starting from said defatted coarse flour of hard wheat. The present invention relates to a method for obtaining naturally-leavened dough and dry naturally-leavened dough therefrom starting from a defatted coarse flour of hard wheat. Another object of the invention is the product thus obtained: a flour product of hard wheat oil, defatted coarse flour and hard wheat lecithin, defatted hard wheat germ and defatted hard wheat bran, naturally leavened dough and dry naturally leavened dough.

Description

Field of the Invention

[0001] The present invention relates to a process for producing food products such as wheat oil, wheat lecithin, natural sourdough, defatted wheat germ and defatted wheat bran starting from selected ground fractions of durum wheat bran and durum wheat germ.

[0002] The present invention also relates to the food ingredients thus obtained, characterized by unique nutritional values ​​and organoleptic properties.

[0003] It is an object of the present invention in particular to provide an apparatus for carrying out the production method of the present invention.

[0004] The production method of the present invention can obtain food ingredients with unique nutritional value and sensory characteristics. Background Art

[0005] Wheat or cereal as we know it is one of the most important cereals for human nutrition and is the most cultivated and consumed in many countries of the world, including Italy.

[0006] Although there are essentially three groups of Triticum wheat, depending on the number of chromosomes, other aspects characterizing the grain, such as whether the husks and glumes are attached to the ripe caryopsis, or the presence of whiskers, allow for other possible classifications, such as naked or dehulled wheat, and correspondingly awn, semiawn and dumb wheat.

[0007] The most cultivated types are durum wheat and common wheat. From a nutritional point of view, that is, from the point of view of composition, characteristics and chemical properties, as well as chemical-physical and physical properties, these two types of wheat are very similar, however, durum wheat, in addition to the difference in the number of chromosomes, also has a slightly higher protein content.

[0008] In contrast, the differences in the products (flour and by-products) obtained from milling are significant: durum wheat produces large grains of flakes and semolina with sharp edges and a slightly amber color, mainly used in pasta production; on the contrary, small white grains are obtained from soft wheat flour, from which processed bread and bakery products are obtained.

[0009] It is well known that bran mainly consists of fiber, mineral salts and antioxidant compounds and is obtained from the pericarp, the outermost part of the wheat caryopsis.

[0010] For many years it was considered a waste product suitable only for feeding livestock, but in recent decades its important role in human nutrition has been recognized. The best known bran is obtained from wheat millings and is commercially available. It is obtained from hard wheat, soft wheat or a mixture of the two.

[0011] The endosperm is located in the innermost part of the caryopsis and is the most important part of the kernel for edible purposes. It contains the aleurone layer, which consists of a single layer of cells rich in high biological value proteins, lipids, vitamins, mineral salts and enzymes. The starchy endosperm is located in the center, in which the cells contain starch granules (60-70%) and storage proteins (8-18%). The shape and size of the starch granules are typical of each cereal, so it is possible to identify the origin of the flour by microscopic examination.

[0012] Finally, the outer membrane called the scutellum is separated from the endosperm, and the embryo or plumule is present inside the caryopsis, representing the part that forms the new plant when the conditions for germination appear. It has a high protein and lipid content. The plumule part is rich in lipids and oxidative and hydrolytic enzymes such as lipase, lipoxygenase and protease; therefore, it is well known that it is necessary to remove microorganisms from flour products, because it causes oxidative and hydrolytic processes that inevitably reduce the durability of flour products.

[0013] To date, the durum wheat milling sector produces semolina and reground semolina, with a yield of 75-80% from the wheat kernel (caryopsis) and 20-25% from by-products, which mainly consist of bran and germ.

[0014] Therefore, bran and germ have specific nutritional and functional characteristics (nutritional bioactive substances), and therefore, they can be valued using food technologies that are suitable for recovering these substances, purifying them and using them as ingredients in foods, pharmaceuticals, food supplements, cosmetics.

[0015] Currently, research is increasingly geared towards a better understanding of food characteristics and lifestyles that generally use better and more effective ways to influence brain capabilities and psychophysiological health, while successfully influencing the molecular mechanisms of neurodegeneration involved in the pathogenesis of aging, including neurodegenerative diseases. Nutritional science is the new frontier, which studies foods that have a positive impact on healthy living, up to healthy aging. Nutritious foods are also called functional foods.

[0016] Nutritional science therefore consists in the study of foods or their components which have a beneficial effect on human health, both in terms of preventive and direct therapeutic effects.

[0017] Wheat germ and bran provide important attributes in nutritional products, but the intrinsic properties of some grains make them difficult to use and result in large amounts of waste during the production process of wheat.

[0018] As is known, lipids in caryopsis are usually hardly considered due to their limited content (maximum concentration in the germ). Nevertheless, their importance is relevant both from a nutritional and a technological point of view. Cereal lipids constitute an extremely heterogeneous class of substances, distributed in a very diverse manner in different cereal tissues.

[0019] Caryopsis contains, in addition to triglycerides, the most common in endosperm tissue, lipids whose functional (emulsifying, stabilizing) properties allow interaction with protein and starch molecules and are of strategic importance for technological transformation.

[0020] Durum wheat has qualitative differences compared to soft wheat in caryopsis lipid composition (Narducci et al., 2019 Research Centre for Food and Nutrition, Council for Agricultural Research and Economics (CREA)) as well as some of the main nutrients specific to the oil such as toochromanols (vitamin E), carotenoids (β-carotene) and sterols.

[0021] Unfortunately, the relative presence of unsaturated and polyunsaturated fatty acids in cereal lipids makes alteration phenomena such as rancidity very frequent.

[0022] Such a high variation makes it easier to preserve the necessary grain refining process (separating only the endosperm); however, the disadvantage is that this process reduces the nutritional value.

[0023] The processes and methods for extracting oil from wheat (germ and bran) have been studied in the literature, and the results consistently show that controlling the free fatty acids (acidic FFA) of these raw materials is very important to maintain the quality of the extracted oil (Vladimiro Cardenia et al. Eur. J. Lipid Sci. Technol. 2018).

[0024] In the literature, the process of grinding durum wheat and the extraction and refining of oil from the by-products obtained result in products containing large amounts of free fatty acids (acidic-FFA) (Squeo G. et al., Foods, vol. 11, n. 5, 2022).

[0025] In the literature, the best qualitative-quantitative characteristics were obtained using solvent (n-hexane) extraction methods.

[0026] In the literature, there are also many studies on stabilizing the germ and bran fractions to control the increase in acidity, which clearly shows that in order to better maintain the quality of the extracted oil, the wheat needs to be properly moistened (Marzocchi et al. Foods 2022) and, above all, the short time frame between grinding and oil extraction needs to be respected so that the latter occurs as soon as possible after peeling / sieving (Vladimiro Cardenia et al. Eur. J. Lipid Sci. Technol. 2018).

[0027] Oil extraction also allows stabilization of the raw materials (germ and bran) from which they are extracted; at this point, the defatted and heat-treated meals (germ and defatted bran) before and after the extraction process are also stable and do not undergo biological changes due to reduced moisture content (6-8%) and water activity (aw<0.3).

[0028] To date, the production process for durum wheat oil extraction is unknown and therefore no food product (ingredient) is obtained from the subsequent processing steps of defatted durum wheat germ and bran with a reduced percentage of free fatty acids and thus a high final product quality.

[0029] There are scientific publications on the properties and uses of defatted wheat germ, but they all refer to soft wheat germ, not hard wheat germ. SUMMARY OF THE INVENTION

[0031] In view of the above, the object of the present invention is to provide a method for producing food ingredients such as wheat oil, wheat lecithin, natural dough, defatted wheat germ, defatted wheat bran and wheat fiber starting from selected ground fractions of durum wheat bran and durum wheat germ.

[0032] The present invention also relates to the food ingredients thus obtained, characterized by unique nutritional values ​​and organoleptic properties.

[0033] The object of the present invention is in particular to provide an apparatus for implementing the production process of the present invention.

[0034] The production method of the present invention can obtain food ingredients with unique nutritional value and sensory characteristics.

[0035] List of drawings Further features and advantages of the method of the invention will become more apparent from the following exemplary but non-limiting description of preferred embodiments of the invention given below with the aid of the accompanying drawings, in which:

[0036] Figure 1 A block diagram showing the method of the invention for obtaining a food product starting from durum wheat;

[0037] Figure 2Block diagram showing the sequence of process steps for obtaining durum wheat oil, defatted meal of durum wheat germ and bran and durum wheat lecithin according to the first aspect of the invention;

[0038] Figure 3 A block diagram showing the sequence of process steps for obtaining a flour product of defatted durum wheat germ and defatted durum wheat bran according to the first aspect of the present invention;

[0039] Figure 4 Block diagram showing the sequence of process steps for obtaining naturally-leavened dough by biological fermentation of defatted meal of durum wheat germ and bran obtained as subject of the process of the invention. DETAILED DESCRIPTION OF THE INVENTION

[0041] Special reference Figure 1 , which schematically represents the steps of a method 50 according to the invention for obtaining a food product starting from durum wheat 10 (Triticum durum), preferably the bran or the germ.

[0042] According to a preferred aspect, the starting durum wheat 10 consists of a mixture selected from 90-60% w / w dehulled durum wheat and 10-40% w / w medium hard wheat, preferably 80%-20% w / w or 70%-30% w / w, and more preferably 60%-40% w / w medium hard wheat.

[0043] Figure 1 The method shown allows to extract refined durum wheat oil 100 from starting durum wheat 10, while obtaining defatted meal 300 and durum wheat lecithin 200, according to Figure 2 , which exemplifies a method 1 of the invention, starting from durum wheat 10 as raw material, and in particular allowing to obtain defatted meal 300 of durum wheat germ and bran.

[0044] The defatted meal 300 of durum wheat germ and bran can advantageously be constituted for obtaining Figure 2 The illustrated defatted durum wheat germ 400 and defatted durum wheat bran 500 are the starting materials of another method 2 for producing a flour product, and the defatted coarse meal 300 of durum wheat germ and bran can constitute the starting material of a method 3 for obtaining a naturally leavened dough 600 by biological fermentation of the coarse meal 300 obtained by method 1 of the present invention.

[0045] The defatted durum wheat bran 500 may advantageously constitute the starting material for obtaining wheat fibres 800 by micronization 4a and turbo separation 4b.

[0046] Advantageously, the selection of the starting durum wheat 10, ie durum wheat bran and germ, for the extraction of wheat oil by the method 1 object of the invention is carried out by analytical studies of marker molecules present in the germ, since the components of the caryopsis have a higher nutritional and functional (nutritional) value.

[0047] Specifically, the retrieved analysis tags are:

[0048] -WGA (wheat germ glutenin), also known as wheat germ agglutinin;

[0049] - Vitamin E, especially the alpha-tocopherol isomer with three methyl groups.

[0050] Wheat germ agglutinin (WGA) is a lectin that protects wheat (Triticum spp.) from insects, bacteria, and yeasts. It is primarily found in seeds and is abundant in wheat germ at 100-500 ppm, so it can be used as an analyte to distinguish milled products containing germ or germ components.

[0051] α-Tocopherol with three methyl groups is a vitamin E isomer and is more biologically active than other homologues. It has a higher antioxidant activity in vivo and is mainly found in the wheat germ fraction.

[0052] Therefore, the specific analytical markers confirming the presence of wheat germ in the selected ground fraction preferably have the following values:

[0053] WGA:>100ppm;

[0054] Vitamin E (α-tocopherol):>8ppm, preferably>10ppm, more preferably>30ppm. According to a preferred aspect, vitamin E (α-tocopherol) is between 30-60ppm, more preferably between 30-50ppm, even more preferably between 30-40ppm. WGA quantitative determination is carried out by ELISA anti-WGA immunoenzyme determination.

[0055] The quantitative determination of vitamin E (α-tocopherol) was performed by high-resolution liquid chromatography (HPLC) according to the ISO 9936:2016 analytical method.

[0056] According to a first aspect of the invention, the process 1 for obtaining durum wheat oil, also called wheat germ oil, as well as durum wheat bran oil and defatted meal oil comprises a durum wheat conditioning step 1a, or advantageously moistening with water, wherein the wheat is moistened to a degree preferably equal to about 3-5% w / w relative to the durum wheat, and allowed to rest in silos called "rest houses".

[0057] According to the invention, the expression durum wheat oil is also intended to mean wheat germ oil.

[0058] Preferably, the wheat conditioning step 1a provides wetting the wheat with water at a pH comprised between 7 and 9.5, preferably between 7 and 9, and the subsequent resting step is carried out for 6 to 8 hours.

[0059] Wetting is an essential process that allows water to penetrate into the caryopsis, making it easier and more effective to mechanically remove the outer layers (bran and germ) in the following mechanical grinding steps (crushing, shelling, etc.).

[0060] According to the invention, the water is filtered or permeated and is characterized by a conductivity value comprised between 5-25 μS / cm. The water may be obtained by microfiltration / ultrafiltration or reverse osmosis, preferably starting from drinking water.

[0061] The conductivity was measured at 25°C according to the APAT CNR IRSA 2030 Man 292003 analytical method.

[0062] The presence of certain pro-oxidative metals (such as iron and copper) and other contaminants in water must be controlled or avoided since it favors fat alteration phenomena (oxidative rancidity); the use of the water of the invention and the control of the pH of the water itself (comprising between 7 and 9) are essential for maintaining the quality of the extracted oil and of the defatted wheat bran and germ originating from extraction method 1.

[0063] The moisture characteristics during wheat wetting are a fundamental parameter controlling lipase activity and the consequent increase in free acidity (FFA), which is very harmful in bran and germ (Vladimiro Cardenia et al. Eur. J. Lipid Sci. Techn0l. 2018).

[0064] After conditioning, the wheat is subjected to a milling step 1b.

[0065] During the first milling step 1 b, pre-cleaning, cleaning and optional selection operations are carried out in order to remove impurities from the different wheat types, which may differ in size, color, density classification of the caryopsis.

[0066] Visual screening is performed using a grain visual screener such as the SORTEX from the Bülher Group.

[0067] In the subsequent milling step 1c, called dehulling, instead of removing most of the bran and germ, it is preferred that the dehulling is equal to or higher than 12% w / w of the caryopsis, thereby completely removing the germ from the kernel. Therefore, if the dehulling rate is lower than 12% w / w, part of the germ will be discarded after the subsequent sieving and milling operation by a flour sifter (plansichter) or purifier.

[0068] In particular, the method of the invention can advantageously provide for the grinding of an average of 4-6 different wheat types from different origins.

[0069] Returning to the steps of method 1, after the grinding steps 1b and 1c, a granulation step 1d is carried out, i.e. a step in which the ground fraction of durum wheat germ and bran is compressed in a machine called a "granulator". This compression step is advantageously carried out by adding a water / steam mixture at a temperature preferably of about 80°C.

[0070] The process of obtaining granules may also be very fast, for example, lasting about 10 minutes from the moment the grinder produces the grinding part to the moment the granules are finally obtained.

[0071] The granules thus obtained are then dried in a drying step 1e, wherein the moisture content of the granules is reduced by at least 5% by weight relative to the total weight of the initial granules. Advantageously, the granules in the granulation step 1d have an average moisture content of 13% w / w, resulting in a final average moisture content of about 8% w / w.

[0072] The drying step 1e may preferably be carried out on a continuous belt, preferably in a HTST (High Temperature Short Time) at a temperature of 90° C. This is to better preserve the nutritional / functional value of the particles themselves.

[0073] After the drying step 1e, the process of the invention provides for an extraction step 1f of the crude oil.

[0074] The extraction step 1f of the crude oil is advantageously carried out by a continuous process of countercurrent flows of an enriched mixture of the solvent n-hexane / wheat oil.

[0075] Preferably, the process is carried out at a temperature of about 65°C for a time period of 4-5 hours, until a maximum residue of oil in the meal equal to 0.5% w / w of the total lipids is obtained.

[0076] According to known methods, after the extraction step 1f of the crude oil, a final step of refining 1 g (1 g-1) of the crude oil is provided, which makes it possible to consume the durum wheat oil 100 thus extracted.

[0077] The refining step 1g enables the production of an edible oil 100 in which the hexane number is within the legally prescribed range.

[0078] The hard wheat oil 100 obtained by the above method 1 is another object of the present invention, for example, it has excellent nutritional value as shown below (Table 1) in addition to the fatty acid composition (Table 2) and chemical and physical analysis (Table 3) as shown below.

[0079] Table 1: Nutritional information for 100g of product:

[0080]

[0081] Table 2: Fatty acid composition % (GLC ISO 5508):

[0082]

[0083]

[0084] Table 3: Chemical and chemico-physical analysis:

[0085]

[0086] *Analyzed during packaging.

[0087] The object of the present invention is also an edible durum wheat oil 100 characterized by a sterol fraction comprising stanols (15-30% w / w canpergol and 15-20% w / w sitostanol) and more preferably having the following chemical and chemicophysical characteristics (Table 4a).

[0088] The unsaponifiable fraction is determined by the UNI EN ISO 3596:2002 method.

[0089] Table 4: Chemical and chemo-physical characteristics

[0090]

[0091]

[0092] Furthermore, edible durum wheat oil 100 has the following characteristics (Table 4b).

[0093]

[0094]

[0095] The refining step 1g may comprise in sequence several sub-processes allowing different products to be obtained, including:

[0096] - by adding specific enzymes lecithinase (e.g. LM) Durum wheat oil 100 is subjected to an enzymatic degumming step 1g-2; during this process step, wheat lecithins are separated enzymatically, which are naturally contained in the oil at a concentration of 3-5% w / v. After the enzymatic treatment, a water / lecithin mixture is obtained, which is subsequently dried. The lecithins 200 thus obtained are widely used in the food sector for their emulsifying properties; they are a minor ingredient (<3%) in many recipes of leavened baked goods (pandoro, panettone, croissants, etc.);

[0097] - Step 1g-3 of deacidification of durum wheat oil 100, carried out by adding an aqueous sodium hydroxide solution, whereby the free fatty acids (free acidity or FFA) react chemically with the sodium hydroxide itself, forming the so-called soaps. Thus, the free acidity is reduced to the minimum value prescribed by the law for seed oils (art. 18 DPR 22 / 12 / 54 n. 1217);

[0098] - Decolorization step Step 1g-4, which provides for the bleaching of the semi-refined wheat oil to remove pigments, such as mainly carotenoids and possible traces of soaps and other undesirable substances. The removal of such substances is preferably carried out by a physical adsorption process on a chemically activated bleaching earth, such as activated carbon. The oil placed in a sealed container is contacted with the bleaching earth in a proportion of about 4% w / w at a temperature of 80-90° C. for a period of time that varies depending on the type of oil. The soil is removed by filtration;

[0099] - Deodorization step 1g-5 represents the last operation of the durum wheat oil refining process, providing deodorization of the oil by steam distillation at a temperature comprised between 200 and 260° C. in a high vacuum for a variable time between 30 and 60 minutes. By the deodorization step, all volatile substances, traces of free fatty acids, fatty acid oxidation intermediates, unsaturated hydrocarbons and traces of proteins are removed. In addition, traces of tocopherols, phytosterols, possible phytodrug residues and possible traces of fat-soluble mycotoxins are also removed.

[0100] Another object of the invention is the durum wheat oil 100 further processed and obtained at the end of each step 1g-2, 1g-3, 1g-4 and / or 1g-5.

[0101] At the end of the oil extraction process, durum wheat oil 100 is obtained together with defatted meal 300 constituting an intermediate product suitable for further separation processes in order to obtain a flour product having a high protein and fiber content, as described below.

[0102] As mentioned above, defatted meal 300 constitutes an intermediate product suitable for further separation processes, including method 2 for obtaining flour products of defatted durum wheat germ 400 and defatted durum wheat bran 500 .

[0103] The defatted durum wheat bran 500 can advantageously be subjected to further micronization 4a and turbo-separation 4b to obtain wheat fiber 800 .

[0104] The flour product in question is available only under its trade and product name, provided that it originates from a grinding portion that does not contain an oily fraction and is therefore defatted.

[0105] In order to obtain this flour product of defatted durum wheat germ 400 and defatted durum wheat bran 500, starting from the defatted meal 300 obtained above, a solvent removal step 2a is advantageously carried out, providing convection drying with saturated steam injection at a temperature preferably of about 85°C, preferably for about 1 hour.

[0106] After this solvent removal step 2a, the process 2 of the invention for obtaining a defatted durum wheat germ and bran flour product advantageously provides a micronization step 2b and a separation, preferably by turbine separation or wind classification 2c, of a first preferred embodiment of the process.

[0107] The technical applications of micronization 2b and turbo separation (wind classification) 2c are known in the food industry and both demonstrate that particle size reduction is a determining factor in the separation of the main nutrients (fiber and protein) of defatted meal.

[0108] The method 2 of the present invention for obtaining a flour product of defatted durum wheat germ and bran provides a first high-speed grinding step, preferably carried out by a pin grinder or a pin supermicronizer, preferably a Contraplex pin grinder CW 250II model (ALPINE-HOSOKAWA). Preferably, a rotation speed comprised between 3000-5000 rpm is used.

[0109] The specific ultrafine mill belongs to the family of impact mills with two slave driven pin discs. In counter-rotating mode, higher relative speeds can be achieved than any other impact mill operating with only one machine. The relative speed between the pin discs can reach 240m / s, so they are used for ultrafine grinding of a wide range of different products. The degree of particle size reduction is determined by adjusting the speed of the pin discs.

[0110] The subsequent wind classification step 2c is also referred to in the prior art as turbine separation.

[0111] According to the method 2 for obtaining a flour product of defatted durum wheat germ and bran of the present invention, the wind classification or turbine-separation step 2c is preferably performed by a wind air classifier such as Alpine Turboplex classifier ATP (ALPINE-HOSOKAWA). Advantageously, the main air flow rate can be about 500-1000, preferably 500-800 m / s. 3 / h, and the secondary air flow rate is about 400-800, preferably 400-700m 3 / h.

[0112] After entering the machine, the classifying air flows through the classifying wheel in a centripetal direction. During this process, the classifying wheel extracts powder from the raw material and conveys it to the discharge port; the total material discharged from the classifying wheel slopes downward. The product is fed through the rotary valve on the upper part of the classifier; there are two types of products obtained at the end of the process: one is a fine particle fraction with a smaller particle size, while the other is a coarse particle fraction with a larger particle size.

[0113] According to a second preferred embodiment of the method 2 for obtaining a flour product of defatted durum wheat germ and bran according to the present invention, as an alternative to the above-mentioned micronization 2b and turbine separation (wind classification) 2c steps, the separation process of the defatted coarse meal 300 can advantageously provide a triboelectric separation step 2d (or Dry Tribo-electrostatic Protein Enrichment).

[0114] Conventional dry separation methods, such as wind classification and screening, are based on differences in size and / or density of particles used as a driving force. Nevertheless, particles with different compositions can be ground to similar sizes, which limits the maximum purity level that can be obtained.

[0115] By separating the fiber pieces from the proteins, the protein content of the product obtained at the end of the fraction is further increased. To achieve such a result, in a second preferred embodiment of the method 2 for obtaining a defatted durum wheat germ and bran flour product according to the invention, the particles are subjected to an electrostatic separation, which particles are separated based on their different triboelectric charge behavior.

[0116] Electrostatic separation of particles is obtained by first charging the particles and then separating them in an external electric field (Haga, 1995); in this particular case, this occurs by passing the micronized defatted meal 300 (i.e. obtained downstream of the micronization step 2b) on two conveyor belts that are opposite and differently charged. The separation occurs by the different adhesion forces of the compounds on the belts.

[0117] The flour product of defatted durum wheat germ 400 obtained with the method 2 for obtaining flour products described so far is characterized by a high protein content, higher than 25% w / w, as better shown in Table 5, where the average analytical properties of defatted durum wheat germ flour 400 are reported.

[0118] As mentioned above, the defatted meal 300 of durum wheat germ and bran constitutes an intermediate product that can be subjected to other separation methods, including the method 3 of obtaining naturally risen dough by biological fermentation.

[0119] Starting from the defatted meal 300 obtained above, a solvent removal step 3a is advantageously carried out, providing convective drying by saturated steam injection at atmospheric pressure, at a temperature preferably of about 100° C., preferably for about 1 hour.

[0120] After the solvent removal step 3a, the method 3 of the present invention for obtaining naturally leavened dough by biological fermentation of defatted coarse powder of durum wheat germ and bran 300 advantageously provides a biological fermentation step 3b, characterized in that it is inoculated with a starter of lactic acid bacteria, which are suitable for nutritional and functional improvement of the defatted coarse powder of durum wheat germ 300.

[0121] More specifically, advantageously, said biological fermentation step 3b provides for achieving a starter consisting of a mixture of water (50% w / w) and meal (50% w / w) and inoculated with lactic acid bacteria, preferably Lactobacillus plantarum (more preferably strain T6-B10) and Fructilactobacillus sanfranciscensis (more preferably strain A2S5), the cell density in this mixture being 6 log10 UFC / g.

[0122] After the incubation step, preferably at 25° C. for 16 h, a Type II natural hair head 600 (not dehydrated) is obtained.

[0123] The product thus obtained can advantageously be subjected to a drying step 3c, preferably by dehydrating in an oven at 55°C for about 16 hours, to obtain a type III (dehydrated) naturally-risen dough head 700.

[0124] The resulting dried natural dough head 700 is used as an ingredient in fermented baked goods, with great results in terms of sensory (smell, taste) characteristics and flavor improvement due to the significant natural presence of glutamic acid.

[0125] As shown, the process of the present invention can advantageously also obtain durum wheat oil 100 and defatted meal 300 in addition to the flour products of defatted durum wheat germ 400 and defatted durum wheat bran 500 having special nutritional values ​​and organoleptic characteristics.

[0126] Another object of the present invention is the use of the flour product of defatted durum wheat germ 400 and defatted durum wheat bran 500 obtained according to the present invention in the preparation of food, in particular whole wheat pasta.

[0127] The following examples further illustrate the invention. Example

[0128] Example 1 - Preparation of hard wheat oil 100 and defatted meal 300

[0129] Durum wheat characterized by WGA>100 ppm and alpha-tocopherol>30 ppm is wetted, advantageously with filtered water at pH 7, with a conductivity value of 5 μS / cm, relative to reaching 3% w / w of the durum wheat, and kept still for 6 hours in a silo called "rest house".

[0130] After conditioning, the wheat undergoes a grinding step 1b and screening of the grinding fraction. During the first grinding step 1b, pre-cleaning, cleaning and optical selection operations are carried out, while in the second grinding step 1c, called dehulling, on the contrary, most of the bran and germ are removed.

[0131] At this point, while the inner part of the peeled caryopsis continues the grinding process, the peeled outer part is sent directly to the oil extraction plant. Conversely, from the grinding process of the peeled caryopsis, other by-products containing bran and germ, usually called "midranges", are derived, which are also sent directly to the oil extraction process in a continuous flow. Then, a mixture consisting of 60% w / w peeled durum wheat and 40% w / w durum wheat midrange is obtained. Thereafter, a granulation step 1d is carried out, i.e. the ground part of durum wheat germ and bran is pressed in a granulator at a temperature of 80°C for 10 minutes.

[0132] At the end of this step, in which the ground part is produced by the grinder until the final granules are formed, they are dried on a continuous belt at a temperature of 90° C. in a HTST (High Temperature Short Time) (step 1e) while adding a water / steam mixture at a temperature preferably of about 90° C. until a final moisture of 8% w / w is obtained.

[0133] After the drying step 1e, a step 1f of extracting crude oil from the dried granules is started, which is carried out for 4 hours at a temperature of 65°C in a countercurrent flow of a mixture enriched with the solvent n-hexane, until the maximum oil residue in the meal is equal to 0.5% w / w of the total lipids. Crude durum wheat oil and defatted meal of durum wheat germ and bran 300 are then obtained, which are intermediate products for subsequent processing.

[0134] 1g of the crude oil to be consumed is refined and contains:

[0135] - By adding Step 1g-2 of enzymatic degumming of durum wheat oil 100 by LM; during this process step, wheat lecithin 200, which is naturally contained in the oil at a concentration of 3-5% w / v, is separated enzymatically;

[0136] - Deacidification step 1g-3 of durum wheat oil 100;

[0137] - a decolorization step 1g-4, wherein the oil in a sealed container is contacted with bleaching earth in a ratio of 4% w / w at a temperature of 80°C. The earth is removed by filtration;

[0138] Deodorization step 1g-5 provided deodorization of oil by steam distillation at a temperature of 230°C in high vacuum for 30 minutes.

[0139] At the end of refining step 1g, wheat oil 100 characterized as in Tables 1, 2, 3 and 4 is obtained.

[0140] Example 2 - Preparation of defatted durum wheat germ 400 and defatted durum bran 500 flour products

[0141] Starting from the defatted coarse powder 300 obtained according to Example 1, a solvent removal step 2a is carried out, in which the coarse powder is dried by convection with saturated steam injection at a temperature of 95° C. and atmospheric pressure for 1 hour. Subsequently, a micronization step 2b is carried out, in which the solvent-free defatted coarse powder is micronized with a pin grinder or a pin micronizer at a speed of 3000 rpm. Finally, the solvent-free defatted coarse powder is micronized with an air classifier (step 2c) at a speed of about 500 m 3 / h main air velocity and about 400m 3 The solvent-free and micronized defatted meal is sorted at a secondary air flow rate of 1.5 / h. At the end of this process (process 2), defatted durum wheat germ flour 400 and defatted durum wheat bran 500 are obtained, the former characterized by a high protein content, higher than 25% w / w, as better shown in Table 5; the latter characterized by a high content of total dietary fiber (TDF), higher than 45% w / w, and a high content of arabinoxylans, higher than 25% w / w.

[0142] Example 3 - Characterization of defatted durum wheat germ and defatted durum wheat bran flour

[0143] The average analytical characteristics of the defatted wheat germ flour 400 obtained according to Example 2 were determined, as reported in Table 5.

[0144] Table 5: Average analytical characteristics of defatted wheat germ

[0145]

[0146] In order to prove that the above flour (FF) is defatted durum wheat germ flour 400, a laboratory analysis was carried out in order to be able to quantify the WGA present in a certain number of triplicate samples of this flour fraction 400 and pure durum wheat germ (WG) as a reference sample.

[0147] The results obtained are shown below (Table 6):

[0148] Table 6: Laboratory test results of flour (FF)

[0149]

[0150] To prove that the flour (FF) is defatted durum wheat germ, two samples were tested. The test results are as follows:

[0151] -H0: There is no statistically significant difference between the average WGA content in FF and WG;

[0152] -H1: There is a statistically significant difference between the average WGA content in FF and the average WGA content in WG.

[0153] The laboratory test results are shown in Table 7.

[0154] Table 7

[0155] Since the p-value is above 0.05, the null hypothesis cannot be rejected. Therefore, based on the tests performed, it can be concluded that there is a statistically significant difference between the mean WGA content in FF and the mean WGA content in WG within a 95% confidence interval.

[0156] Therefore, this fraction FF consists of defatted wheat germ. This assumption is also confirmed by other chemical analyses, including the qualitative-quantitative composition of the protein fraction. In particular:

[0157] -Soluble protein (albumin and globulin): >40% w / w of total protein;

[0158] - "Limiting" amino acid lysine: >4.5g / 100g of total protein.

[0159] Based on what has been widely reported in the scientific literature regarding the qualitative composition of wheat germ protein.

[0160] The defatted durum wheat bran flour product 500 obtained with the method 2 for obtaining a flour product described so far is characterized by a high fiber content (total dietary fiber > 50%).

[0161] Based on nutritional characteristics, the flour meets the commodity and product definitions of defatted wheat bran.

[0162] The average analytical characteristics of defatted wheat bran are listed in Table 8 below.

[0163] Table 8

[0164]

[0165] Example 4 - Preparation and characterization of Type 2 dough from durum wheat germ and bran

[0166] Starting from the defatted meal 300 obtained according to Example 1, a solvent removal step 3a is carried out, which consists in convection drying with saturated steam injection at a temperature of about 95° C. and at atmospheric pressure for about 1 hour.

[0167] Thereafter, biofermentation step 3b was performed by preparing a mixture consisting of water (50% w / w) and meal (50% w / w) and a starter of lactic acid bacteria Lactobacillus plantarum T6-B10 and Lactobacillus sanfranciscosa A2S5, in which the cell density was 6 log10 UFC / g.

[0168] After an incubation step of 16 h at 25° C., a Type II natural hair head 600 (not dehydrated) was obtained.

[0169] The product thus obtained is dried in an oven at 55° C. for about 16 hours to obtain a Type III natural hair head 700 (dehydrated).

[0170] In Table 9 below, the parameters characterizing the product during the process are reported, in particular during the drying step 3c from time t0 (at the start of the process) to time t16 (at the end of the process).

[0171] Table 9: Product parameters during the process

[0172]

[0173] TTA = Total Titratable Acidity; LAB = Lactic Acid Bacteria

[0174] As mentioned above, the composition of protein amino acids after fermentation had a significant qualitative-quantitative increase, as shown in Table 10 below.

[0175] From a nutritional point of view, this increase is very important.

[0176] Table 10: Amino acid composition of meal protein

[0177]

[0178]

[0179] In the following Table 11 the average composition of Type 2 dough obtained from defatted meal is reported.

[0180] Table 11: Average Nutritional Claims for Type 2 Soaked Dough from Defatted Meal

[0181]

[0182] Example 5 - Characterization of Oil Extracted from Durum Wheat Germ and Bran

[0183] method

[0184] Method for extracting fat from wheat grains: DM 23-07-1994 SO n.4G.Un186 of 10 / 08 / 1994

[0185] FFA: Determination method according to UNI EN ISO 660

[0186] The effects of water quality and pH used for the durum wheat conditioning step or wetting 1a on the extracted oil characteristics were evaluated.

[0187] Two batches of durum wheat oil were analysed after conditioning with drinking water and permeate water (pH comprised between 7 and 9.5) and characterised by conductivity values ​​comprised between 5 and 25 μS / cm, and each sample was subsequently analysed in triplicate.

[0188] In Table 12, the free acidity percentage results are shown (FAA expressed as % m / m of free oleic acid present).

[0189] Table 12

[0190] batch number Wheat conditioned with drinking water mixture Wheat conditioned with osmotic water mixture % Acidity (% w / w Oleic Acid) % Acidity (% w / w Oleic Acid) 888 9.4±0.2 5.5±0.2 213169 8.3±0.2 4.9±0.8

[0191] According to the conditioning step or wetting 1a of the method of the invention, it is evident from Table 12 that the acidity values ​​measured in the wheat conditioned with percolation water are significantly lower compared to the average values ​​of the acidity values ​​in the wheat conditioned with drinking water.

Claims

1. A method for obtaining durum wheat oil and defatted meal starting from durum wheat, characterized in that The content is WGA>100ppm and α-tocopherol>8ppm, preferably>10ppm, more preferably>30ppm, wherein the method comprises the following steps: - Conditioning or moistening of durum wheat 1a, wherein the wheat is moistened with filtered or permeated water, and characterized in that The conductivity value is contained between 5-25 μS / cm, and then left to stand; - Optical screening of first grinding 1b and grinding fractions; - Secondary grinding of peeling 1c; - Granulate for 1 day to obtain granules; - Pellet drying 1e; - Crude oil extraction 1f; - Refining 1 g gave durum wheat oil and defatted meal.

2. The method according to claim 1, wherein the alpha-tocopherol ranges from 30 to 60 ppm, preferably from 30 to 50 ppm, more preferably from 30 to 40 ppm.

3. The method according to claim 1 or 2, wherein the durum wheat conditioning step 1a provides for wetting the wheat with a variable amount of water ranging from 3% w / w to 5% w / w relative to the durum wheat at a pH comprised between 7 and 9.

4. The method according to claims 1-3, wherein the standing step is carried out for 6-8 hours.

5. A process according to claims 1-4, wherein the step 1f of extraction of crude oil is carried out by a continuous process by feeding the raw oil in counter currents of an enriched mixture of solvent n-hexane / wheat oil.

6. Process according to claim 5, wherein the extraction is carried out at a temperature of 65°C for a period of 4-5 hours, until a maximum residual content of oil in the meal equal to 0.5% w / w of the total lipids is obtained.

7. The process according to claims 1-6, wherein the refining step 1g comprises a step 1g-2 of enzymatic degumming of the durum wheat oil by adding the enzyme lecithinase.

8. The process according to claims 1 to 7, wherein the refining step 1g comprises a step 1g-3 of deacidification of the durum wheat oil by adding an aqueous sodium hydroxide solution.

9. The process according to claims 1-8, wherein the refining step 1g comprises a step 1g-4 of bleaching the durum wheat oil.

10. The process according to claims 1-9, wherein the refining step 1g comprises a step 1g-5 of deodorizing the durum wheat oil.

11. Process for obtaining a flour product of defatted durum wheat germ and defatted durum wheat bran starting from defatted meal obtained according to claim 1, wherein the process comprises the following steps: - Removal of solvent 2a by drying the crude powder; - Micronization 2b and separation 2c of micronized defatted meal.

12. A method for obtaining naturally risen dough starting from the defatted meal obtained according to claim 1, wherein the method comprises the following steps: - Removal of solvent 2a by drying the crude powder; - achieving 2b consisting of a mixture of 50% w / w water and 50% w / w dry meal obtained in step 2a and a lactic acid bacteria starter inoculum, and subsequent incubation to obtain a non-dehydrated Type 2 leavened dough; - Possible drying 3c to obtain a dehydrated natural rise.

13. The method according to claim 12, wherein the starter consists of Lactobacillus plantarum, preferably strain T6-B10, and Lactobacillus sanfranciscosa, preferably strain A2S5, wherein the cell density in the mixture is 6 log10 UFC / g.

14. A process for obtaining wheat fiber starting from defatted durum wheat bran obtained according to claim 11, wherein the process comprises the following steps: - micronized 4a, and - Turbine-Separator 4b.

15. Durum wheat oil obtainable by the process of claims 1-10.

16. Durum wheat oil according to claim 14, characterised in that The phenolic fraction contained 20-30% w / w campestrol.

17. Durum wheat oil according to claim 14, further comprising 10-20% w / w campesterol.

18. Defatted meal obtained by the process of claim 1.

19. Defatted durum wheat germ and defatted durum wheat bran flour products obtained by the process of claim 11.

20. Naturally-haired hair obtained by the method of claim 12 or 13.

21. Plant for obtaining durum wheat oil and defatted meal starting from durum wheat according to claims 1 to 10, characterized in that It comprises at least one grinder or fine impactor or pin-type ultra-fine powder pulverizer and at least one wind classifier.

22. The apparatus according to claim 19, wherein the pin-type micronizer performs a high-speed grinding step, preferably using a speed comprised between 3,000 and 5,000.

23. Apparatus according to any one of claims 19 or 20, characterised in that The pin grinder is of the type comprising two counter-rotating driven pin discs, preferably using a relative speed between the discs of about 240 m / s.

24. The apparatus according to one or more of claims 19 to 21, wherein the wind classifier is a cyclone separator, wherein the main air velocity is 500 to 1000 m / s. 3 / h, preferably 500-800m 3 / h, and the secondary air velocity is about 400-800m 3 / h, preferably 400-700m 3 / h.

25. An apparatus for obtaining durum wheat oil and defatted meal starting from durum wheat, characterized in that The apparatus comprises an ultrafine powder pulverizer and, downstream of the ultrafine powder pulverizer, a triboelectric separator suitable for achieving electrostatic separation of pre-charged particles.

26. The device according to claim 24, characterized in that The triboelectric separator comprises a pair of opposing conveyor belts with different charges.

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