Spray drying process of biosurfactants

Abstract

The invention relates to a spray drying process of biosurfactants and the products obtained with it.

Description

Spray drying process of biosurfactantsField of the inventionThe invention relates to a spray drying process of biosurfactants and the products obtained with it.Prior artBiosurfactants are glycolipids produced by fermentation. Due to this way of manufacture the biosurfactants are provided in a form of a high-water content.To facilitate transportation and further processing it is advantageous to separate off at least major portions of the water from the biosurfactant.However, so far, there is no suitable method available, that yields a solid glycolipid product which is not sticky and free-flowing.It is an object of the invention to provide a process yielding in free-flowing, solid biosurfactants.Description of the inventionIt was found that, surprisingly, that the process as instantly claimed solves the problem described above.The present invention therefore provides a spray-drying process according to claim 1 .The invention further provides a solid composition according to claim 11 and 12.One advantage of the present invention is that the products obtained by the process according to the instant invention are free flowing.Another advantage of the present invention is that the products obtained by the process according to the instant invention are non-sticky.Another advantage of the present invention is that the products obtained by the process according to the instant invention have a low dustiness.Another advantage of the present invention is that the products obtained by the process according to the instant invention can be produced in a purely bio-based way.A further advantage is that the products obtained by the process according to the instant invention are biodegradable.Another advantage of the present invention is that the products obtained by the process according to the instant invention (re-)dissolve fast and easily in water.A further advantage is that the products obtained by the process according to the instant invention bear advantageous surface-active properties.A further advantage is that the process according to the instant invention is fast.Another advantage is that the process according to the instant invention does not need high amounts of energy.One advantage of the present invention is that the compositions according to the instant invention have a good storage stability and low clumping tendency.One advantage of the present invention is that the compositions according to the instant invention have a positive odour profile.Another advantage of the present invention is that the compositions according to the instant invention have an improved colour stability.A further advantage is that the compositions according to the instant invention have improved cleaning properties of surfaces.Another advantage is that the compositions according to the instant invention have excellent foaming properties.A further advantage of the compositions according to the instant invention is their reduced irritation for human skin.Another advantage of the compositions according to the instant invention is their mildness and good physiological compatibility, in particular characterized by a high value in the red blood cell (RBC) test.A further advantage of t the compositions according to the instant invention is their good skin feel during and after washing.Another advantage of the compositions according to the instant invention is that they leave behind a smooth and soft skin feel after washing.Another advantage is that the compositions according to the instant invention is their outstanding microbial stability.Another advantage is that the compositions according to the instant invention have an improved ability to dissolve oils and fats.Another advantage is that the composition according to the instant invention leads to a better chemical stability of the raw materials, which increases the shelf life.Another advantage is that the composition according to the instant invention leads to a lower formation of side reactions and higher formulation purity.Another advantage of the present invention is that the composition according to the instant invention shows especially good emulsification and dispersing properties.One advantage of the present invention is that the compositions of the instant invention have a very good cleaning performance, especially in fatty stain removal from fabrics.Another advantage of the present invention is that the compositions of the instant invention can be rinsed off from a surface or from fibres, that had been cleaned, very easily.A further advantage is that the compositions of the instant invention support enzyme stability in terms of storage.One advantage of the present invention is the homogeneity of the compositions of the instant invention even at low pH values.Another advantage of the present invention is that the compositions of the instant invention are easier to dissolve, especially in aqueous media.Another advantage of the present invention is that the compositions of the instant invention are easily miscible with other surfactants.A further advantage of the present invention is that the compositions of the instant invention can be incorporate into cosmetic formulations more easily.Another advantage of the present invention is that the compositions of the instant invention allow the formulation of concentrated surfactant formulations, even at very low pH.Another advantage of the present invention is that the compositions of the instant invention have a reduced foam tendency due to their high concentration and the low achievable pH value, thus simplifying transport and delivery.Another advantage of the present invention is that the compositions of the instant invention allow for easy incorporation of hydrophobic components such as oils.Another advantage of the present invention is that the compositions of the instant invention have a high storage stability.A further advantage of the present invention is that the compositions of the instant invention cause less contamination during their production and transport in pipelines and, moreover, allow easier cleaning.Another advantage of the present invention is that the compositions of the instant invention have a very low freezing point, which means that the compositions remain processable even at low temperatures.Another advantage of the present invention is that the compositions of the instant invention, especially cosmetic or cleaning formulations, will remain colour stable.Another advantage of the present invention is that the compositions of the instant invention, especially cosmetic or cleaning formulations, have a lower colour intensity.The instant invention provides a spray-drying process of biosurfactants comprising the steps ofA) providing a liquid starting composition comprising water and at least one biosurfactant,B) adding maltodextrin to the starting composition,C) spray-drying the water, biosurfactant and maltodextrin comprising composition characterized in that said biosurfactant is comprised in an amount of from 5.0 wt.-% to 60.0 wt.-%, preferably from 10.0 wt.-% to 55.0 wt.-%, more preferably from 15.0 wt.-% to 50.0 wt.-%, and that said maltodextrin is comprised in an amount of 0.2 wt.-% to 30.0 wt.-%, preferably0.5 wt. % to 20 wt.-%, more preferably 0.75 wt.-% to 12.0 wt.-%, wherein the weight percentages refer to the sum of the total starting composition and maltodextrin.In the process according to the instant invention it is essential to use maltodextrin. It primarily serves as carrier material. Other common carrier materials know from the literature to be useful in spry drying processes are carbohydrate polymers, such as the following:• starch and modified starches• hydrolysed starch, i.e. corn syrup solids• cellulose and cellulose derivates (microcrystalline cellulose, hemicellulose, carboxymethyl cellulose, methylcellulose)• gums such as gum arabic, gum guar, gum xanthan• sugars such as dextrin, trehalose, lactose• polyols such as maltitol, sorbitol, xylitol.However, the above have the disadvantages of high price, high hygroscopicity, low molecular weight, inconsistent quality among batches and / or poor water solubility.However, in the process according to the instant invention any of the above mentioned carrier materials can be comprised in the starting composition of process step B), preferably in an amount by weight of the sum of all above mentioned carrier materials less than the maltodextrin.Within the context of the present invention, “biosurfactants” are understood as meaning all glycolipids produced by fermentation. The term “biosurfactant” also covers glycolipids that are chemically or enzymatically modified after fermentation, as long as structurally a glycolipid remains. Raw materials for producing the biosurfactants that can be used are carbohydrates, in particular sugars such as e.g. glucose and / or lipophilic carbon sources such as fats, oils, partial glycerides, fatty acids, fatty alcohols, long-chain saturated or unsaturated hydrocarbons.In the context of the present invention, the terms “surfactant” is understood to mean organic substances having interface-active properties that have the ability to reduce the surface tension of water at 20°C and at a concentration of 0.5 wt.-% based on the overall composition to below 45 mN / m. Surface tension is determined by the Du Nouy ring method at 20°C.Where average values are stated hereinbelow, then, unless stated otherwise, these are number- averaged average values.Unless stated otherwise, percentages are data in percent by weight. The same is true for parts per million (ppm).Wherever measurement values are stated hereinbelow, then, unless stated otherwise, these have been determined at a temperature of 25°C and a pressure of 1013 mbar.When determining the content of substances in the context of the present invention, the mass of the non-salt form is taken into account; thus, the weight of the corresponding cation is disregarded.Preferably, the process according to the instant invention is characterized in that said biosurfactant is selected from the group comprising, preferably consisting of, rhamnolipids, in particular mono-, di- or polyrhamnolipids, glucolipids, in particular mono-, di- or polyglucolipids, and sophorolipids, in particular mono-, di- or polysophorolipids, preferably selected from rhamnolipids and glucolipids, most preferably rhamnolipids.The term "rhamnolipids" in the context of the present invention preferably is understood to mean particularly compounds of the general formula (I) and salts thereof,Formula (I) where mRL = 2, 1 or 0, preferably 1 or 0, nRL = 1 or 0,R1RLand R2RL= mutually independently, identical or different, organic residues having 2 to 24, preferably 5 to 13 carbon atoms, in particular optionally branched, optionally substituted, particularly hydroxy-substituted, optionally unsaturated, in particular optionally mono-, bi- or triunsaturated alkyl residues, preferably those selected from the group consisting of pentenyl, heptenyl, nonenyl, undecenyl and tridecenyl and (CH2)o-CH3 where o = 1 to 23, preferably 4 to 12. If nRL = 1 , the glycosidic bond between the two rhamnose units is preferably in the a-configuration. The optically active carbon atoms of the fatty acids are preferably present as R-enantiomers (e.g. (R)-3-{(R)-3-[2-O-(a-L-rhamnopyranosyl)-a-L-rhamnopyranosyl]oxydecanoyl}oxydecanoate).The term "di-rhamnolipid" in the context of the present invention is understood to mean compounds of the general formula (I) or salts thereof, where nRL = 1 .The term "mono-rhamnolipid" in the context of the present invention is understood to mean compounds of the general formula (I) or salts thereof, where nRL = 0.Distinct rhamnolipids are abbreviated according to the following nomenclature: "diRL-CXCY" are understood to mean di-rhamnolipids of the general formula (I), in which one of the residues R1RLand R2RL= (CH2)o-CH3 where o = X-4 and the remaining residue R1or R2= (CH2)O-CH3where o = Y-4."monoRL-CXCY" are understood to mean mono-rhamnolipids of the general formula (I), in which one of the residues R1RLand R2RL= (CH2)O-CH3 where o = X-4 and the remaining residue R1RLor R2RL= (CH2)O-CH3where o = Y-4.The nomenclature used therefore does not distinguish between "CXCY" and "CYCX". For rhamnolipids where mRL=0, monoRL-CX or diRL-CX is used accordingly.If one of the abovementioned indices X and / or Y is provided with ":Z", this signifies that the respective residue R1RLand / or R2RLis equal to an unbranched, unsubstituted hydrocarbon residue having X-3 or Y-3 carbon atoms having Z double bonds.Rhamnolipids applicable in the context of the instant invention can also be produced by fermentation of Pseudomonas, especially Pseudomonas aeruginosa, which are preferably non genetically modified cells, a technology already disclosed in the eighties, as documented e.g. in EP0282942 and DE4127908. Rhamnolipids produced in Pseudomonas aeruginosa cells which have been improved for higher rhamnolipid titres by genetical modification can also be used in the context of the instant invention; such cells have for example been disclosed by Lei et al. in Biotechnol Lett. 2020 Jun;42(6):997-1002.Rhamnolipids produced by Pseudomonas aeruginosa are commercially available from Jeneil Biotech Inc., e.g. under the tradename Zonix,from Logos Technologies (technology acquired by Stepan), e.g. under the tradename NatSurFact, from Biotensidion GmbH, e.g. under the tradename Rhapynal, from AGAE technologies, e.g. under the name R90, R95, R95Md, R95Dd, from Locus Bio-Energy Solutions and from Shanghai Yusheng Industry Co. Ltd., e.g. under the tradename Bio- 201 Glycolipids.The present invention provides a process preferably using as said biosurfactant rhamnolipids, characterized in that the rhamnolipids comprise51 wt.-% to 100 wt.-%, preferably 60 wt.-% to 95 wt.-%, particularly preferably 80 wt.-% to 90 wt.- %, of mono-rhamnolipids, especially those of formula (I) with nRL=0, where the percentages by weight refer to the sum of all of the rhamnolipids comprised in the composition.The present invention provides a process alternatively preferably using as said biosurfactant rhamnolipids, characterized in that the rhamnolipids comprise71 wt.-% to 100 wt.-%, preferably 75 wt.-% to 95 wt.-%, particularly preferably 80 wt.-% to 90 wt.- %, of di-rhamnolipids, especially those of formula (I) with nRL=1 ,where the percentages by weight refer to the sum of all of the rhamnolipids comprised in the composition.The present invention further provides a process preferably using as said biosurfactant rhamnolipids, characterized in that the rhamnolipids comprise56 wt.-% to 95 wt.-%, preferably 60 wt.-% to 80 wt.-%, particularly preferably 66 wt.-% to 70 wt.-%, of diRL-C10C10, where the percentages by weight refer to the sum of all of the rhamnolipids comprised in the composition.A preferred process according to the invention is characterized in that it uses as said biosurfactant rhamnolipids as described above with a content of0.5 wt.-% to 15 wt.-%, preferably 3 wt.-% to 12 wt.-%, particularly preferably 5 wt.-% to 10 wt.-%, of diRL-C10C12:1 , where the percentages by weight refer to the sum of all of the rhamnolipids comprised in the composition.A further preferred process according to the invention is characterized in that it uses as said biosurfactant rhamnolipids as described above with a content of0.5 to 25 wt.-%, preferably 3 wt.-% to 15 wt.-%, particularly preferably 5 wt.-% to 12 wt.-%, of diRL- C10C12, where the percentages by weight refer to the sum of all of the rhamnolipids comprised in the composition.A preferred process according to the invention is characterized in that it uses as said biosurfactant rhamnolipids as described above with a content of0.1 wt.-% to 25 wt.-%, preferably 2 wt.-% to 10 wt.-%, particularly preferably 4 wt.-% to 8 wt.-%, of diRL-C8C10, where the percentages by weight refer to the sum of all of the rhamnolipids comprised in the composition.An even further preferred process according to the invention is characterized in that it uses as said biosurfactant rhamnolipids as described above with a content of0.1 wt.-% to 5 wt.-%, preferably 0.5 wt.-% to 3 wt.-%, particularly preferably 0.5 wt.-% to 2 wt.-%, of monoRL-C8C10 and / or, preferably and0.1 wt.-% to 5 wt.-%, preferably 0.5 wt.-% to 3 wt.-%, particularly preferably 0.5 wt.-% to 2 wt.-%, of monoRL-C10C10, where the percentages by weight refer to the sum of all of the rhamnolipids comprised in the composition.The present invention provides a process alternatively preferably using as said biosurfactant rhamnolipids, characterized in that the rhamnolipids comprise10 wt.-% to 30 wt.-%, preferably 20 wt.-% to 30 wt.-%, particularly preferably 25 wt.-% to 30 wt.-%, of monoRL-C10C10, where the percentages by weight refer to the sum of all of the rhamnolipids comprised in the composition.The alternatively preferred process according to the invention is characterized in that it uses as said biosurfactant rhamnolipids as described above with a content of10 wt.-% to 30 wt.-%, preferably 12 wt.-% to 25 wt.-%, particularly preferably 15 wt.-% to 20 wt.-%, of diRL-C10C10, where the percentages by weight refer to the sum of all of the rhamnolipids comprised in the composition.The alternatively preferred process according to the invention is characterized in that it uses as said biosurfactant rhamnolipids as described above with a content of10 wt.-% to 30 wt.-%, preferably 12 wt.-% to 25 wt.-%, particularly preferably 15 wt.-% to 20 wt.-%, of monoRL-C8C10, where the percentages by weight refer to the sum of all of the rhamnolipids comprised in the composition.The alternatively preferred process according to the invention is characterized in that it uses as said biosurfactant rhamnolipids as described above with a content of3 wt.-% to 25 wt.-%, preferably 5 wt.-% to 20 wt.-%, particularly preferably 10 wt.-% to 15 wt.-%, of monoRL-C10C12:1 , where the percentages by weight refer to the sum of all of the rhamnolipids comprised in the composition.The alternatively preferred process according to the invention is characterized in that it uses as said biosurfactant rhamnolipids as described above with a content of1 wt.-% to 15 wt.-%, preferably 2 wt.-% to 10 wt.-%, particularly preferably 3 wt.-% to 8 wt.-%, of diRL-C10C12, where the percentages by weight refer to the sum of all of the rhamnolipids comprised in the composition.In the context of the present invention, the term “sophorolipids” preferably is understood as meaning compounds of the general formulae (Ila) and (lib) and salts thereofwhereR1SL= H or CO-CH3,R2SL= H or CO-CH3,R3si_ =adivalent organic moiety which comprises 6 to 32 carbon atoms and which is unsubstituted or substituted by hydroxyl functions, is unbranched and optionally comprises one to three double or triple bonds,R4SL= H, CH3 or a monovalent organic radical which comprises 2 to 10 carbon atoms and which is unsubstituted or substituted by hydroxyl functions, which is unbranched and which optionally comprises one to three double or triple bonds, and nSL = 1 or 0.Sophorolipids may be used in accordance with the invention in their acid form or their lactone form. Preferred processes according to the invention use a sophorolipid in which the ratio by weight of lactone form to acid form is in the range of 20:80 to 80:20, especially preferably in the ranges of 30:70 to 40:60.To determine the content of sophorolipids in the acid or lactone form in a formulation, refer to EP141111 1 B1 , page 8, paragraph

[0053] ,In connection with the present invention, the term “glucolipids” preferably is understood as meaning compounds of the general formula (III) and salts thereof,where mGL = 3, 2, 1 or 0, preferably 1 or 0,R1GLand R2GL= independently of one another identical or different organic radical having 2 to 24 carbon atoms, in particular optionally branched, optionally substituted, in particular hydroxysubstituted, optionally unsaturated, in particular optionally mono-, di- or triunsaturated, alkyl radical, preferably one selected from the group consisting of pentenyl, heptenyl, nonenyl, undecenyl and tridecenyl and (CH2)o-CH3 where 0 = 1 to 23, preferably 4 to 12.Distinct glucolipids are abbreviated according to the following nomenclature:“GL-CXCY” is understood as meaning glucolipids of the general formula (III) in which one of the radicals R1GLand R2GL= (CH2)o-CH3 where 0 = X-4 and the remaining radical R1GLor R2GL= (CH2)o- CH3 where 0 = Y-4.The nomenclature used thus does not differentiate between “CXCY” and “CYCX”.If one of the aforementioned indices X and / or Y is provided with “:Z”, then this means that the respective radical R1GLand / or R2GL= an unbranched, unsubstituted hydrocarbon radical with X-3 or Y-3 carbon atoms having Z double bonds.Methods for production of glucolipids can be carried out as described in WO2019154970.A preferred process according to the instant invention is characterized in that maltodextrin is added in an amount, that the weight ratio of biosurfactant and maltodextrin is in the range of from 2:1 to 40:1 , preferably from 3:1 to 35:1 , preferably from 4:1 to 30:1 , even more preferably from 5:1 to 28:1 , most preferably from 8:1 to 25:1 .A preferred process according to the instant invention is characterized in that said added maltodextrin has a dextrose equivalent (DE) from 2 % to 30 %, preferably 3 % to 22 %, more preferably 4 % to 12 %, even more preferably 4 % to 8 %.In a preferred process according to the instant invention in process step B) the maltodextrin and the starting composition are suspended using a dissolver disc.In a preferred process according to the instant invention said liquid starting composition comprises water in an amount of 20 wt.-% to 98 wt.-%, preferably from 40 wt.-% to 95 wt.-%, more preferably from 60 wt.-% to 90 wt.-%, wherein the weight percentages refer to the total liquid starting composition.A preferred process according to the instant invention is characterized in that the water, biosurfactant and maltodextrin comprising composition in process step C) has a total solid content of from 6.0 wt.-% to 80.0 wt.-%, preferably from 12.0 wt.-% to 60.0 wt.-%, more preferably from 16.0 wt.-% to 40.0 wt.-%.A preferred process according to the instant invention is characterized in that in process step C) a drying gas, preferably selected from nitrogen and air, at a temperature from 120 °C to 800 °C, preferably from 130 °C to 400 °C, more preferably from 140 °C to 170 °C, is used.A preferred process according to the instant invention is characterized in that in process step C) an outlet temperature from 50 °C to 100 °C, preferably from 55 °C to 90 °C, more preferably from 60 °C to 80 °C, is used.A preferred process according to the instant invention is characterized in that in process step C) a nominal main process gas flow of 500 m3 / h to 100,000 m3 / h is used.A preferred process according to the instant invention is characterized in that in process step C) an atomization pressure of 4 bar to 300 bar is used.A preferred process according to the instant invention is characterized in that in process step C) a pressure nozzle, a two-substance nozzle or a rotary disc atomizer is used.The present invention provides a composition comprising at least one biosurfactant and maltodextrin obtainable by the process according to the instant invention.The present invention further provides a solid composition comprising at least one biosurfactant, and maltodextrin, preferably obtainable by the process according to the instant invention.The term “solid” in the context of the instant invention means solid at 25 °C.The compositions according to the instant invention preferably comprise as biosurfactant the biosurfactant preferably used in the context of the process of the instant invention.Thus, for example, preferred compositions according to the instant invention are characterized in that the comprised biosurfactant is selected from rhamnolipids, glucolipids and sophorolipids, preferably rhamnolipids and glucolipids, most preferably rhamnolipids.Preferred compositions according to the instant invention are characterized in that they comprise 60 wt.-% to 95 wt.-%, preferably 70 wt.-% to 90 wt.-%, more preferably 75 wt.-% to 85 wt.-%, of said at least one biosurfactant, and5.0 wt.-% to 40 wt.-%, preferably 10 wt.-% to 30 wt.-%, more preferably 15 wt.-% to 25 wt.-%, maltodextrin. wherein the weight percentages refer to the total composition.Preferred compositions according to the instant invention are solid particles. These compositions according to the instant invention are preferably characterized in that they have a mean particle size of from 4.0 pm to 200 pm, preferably from 6.0 pm to 100 pm, more preferably from 8.0 pm to 50 pm.The mean particle size of the solid particles will be measured as mass median diameter (MMD) by the following method:The particle size distribution of the powder is measured via laser scattering using the Partica LA- 960 (Horiba Scientific). The powder is measured as dry powder using the dry powder accessory. The measurement method is carried out according to the Mie Scattering Theory.Preferred compositions according to the instant invention are characterized in that they have a residual water content of from 1 .0 wt.-% to 10.0 wt.-%, preferably from 2.0 wt.-% to 8.0 wt.-%, more preferably from 3.0 wt.-% to 6.0 wt.-%, wherein the weight percentages refer to the total composition.The residual water content is determined via a thermogravimetric approach. The sample is heated by infrared rays using the Infrared Moisture Analyzer MA35 (Sartorius) which automatically records the weight before, during and after drying and thereby determines the residual water content in weight%. The residual water content is measured at 110 °C.Due to their good solubility the compositions according to the instant invention can be used to formulate end customer products.Thus, the present invention further provides the use of a composition according to the instant invention for formulating an end customer product, preferably selected from the group of cosmetics, pharmaceutics, and cleaning compositions, especially for the household care field.The examples adduced hereinafter describe the present invention by way of example, without any intention that the invention, the scope of application of which is apparent from the entirety of the description and the claims, be restricted to the embodiments specified in the examples.Examples:Rhamnolipids were prepared as described in example 1 of EP3023431.Glucolipids were prepared as described in example 2 of WO2019154970.Sophorolipids used are REWOFERM® SL ONE from Evonik, which has a lactone to acid ratio of 40:60.Example 1: Spray drying of rhamnolipids with maltodextrin (90 / 10), according to the inventionA suspension with a solid content of 20 wt.-% was produced for spray drying. The solids consisted of 90 wt.-% rhamnolipids and 10 wt.-% maltodextrin (DE 4.0-7.0). Therefore, water and the rhamnolipid solution were mixed (50 wt.-% rhamnolipid content) and maltodextrin was dissolved at RT (25 °C) in this mixture under stirring with a magnetic stirrer for 30 min. Spray drying was carried out using the Mini Spray Dryer B-290 (Buchi Labortechnik AG, Flawil, Switzerland) equipped with a two-fluid nozzle. During spray drying, the suspensions were kept agitated by means of a magnetic stirrer bar. The inlet temperature was set at 150 °C and kept constant throughout the process. The atomization nitrogen flow rate and drying air volumetric flow rate were adjusted to -750 L / h and 35 m3 / h, respectively. The pump rate was adjusted to maintain an outlet temperature of 100±1 °C. After spray drying, the samples were collected from the product collection vessel and stored in sealed glass containers to prevent subsequent moisture uptake.Example 2: Spray drying of rhamnolipids with maltodextrin (80 / 20), according to the inventionA suspension with a solid content of 20 wt.-% was produced for spray drying. The solids consisted of 80 wt.-% rhamnolipids and 20 wt.-% maltodextrin (DE 4.0-7.0). Therefore, water and the rhamnolipid solution were mixed (50 wt.-% rhamnolipid content) and maltodextrin was dissolved at RT (25 °C) in this mixture under stirring with a magnetic stirrer for 30 min. Spray drying was carried out using the Mini Spray Dryer B-290 (Buchi Labortechnik AG, Flawil, Switzerland) equipped with a two-fluid nozzle. During spray drying, the suspensions were kept agitated by means of a magnetic stirrer bar. The inlet temperature was set at 150 °C and kept constant throughout the process. The atomization nitrogen flow rate and drying air volumetric flow rate were adjusted to -750 L / h and 35 m3 / h, respectively. The pump rate was adjusted to maintain an outlet temperature of 100±1 °C. After spray drying, the samples were collected from the product collection vessel and stored in sealed glass containers to prevent subsequent moisture uptake.Example 3: Spray drying of glucolipids with maltodextrin (80 / 20), according to the inventionA suspension with a solid content of 20 wt.-% is produced for spray drying. The solids consist of 80 wt.-% glucolipids and 20 wt.-% maltodextrin. Therefore, maltodextrin is dissolved in the glucolipid solution at RT (25 °C) under stirring with a magnetic stirrer for 30 min. Spray drying is carried out at an inlet temperature of 150 °C, which is kept constant throughout the process. The pump rate is adjusted to maintain an outlet temperature of 100 ±1 °C.Example 4: Spray drying of sophorolipids with maltodextrin (80 / 20), according to the inventionA suspension with a solid content of 20 wt.-% is produced for spray drying. The solids consist of 80 wt.-% sophorolipids and 20 wt.-% maltodextrin. Therefore, maltodextrin is dissolved in the sophorolipid solution at RT (25 °C) under stirring with a magnetic stirrer for 30 min. Spray drying is carried out at an inlet temperature of 150 °C, which is kept constant throughout the process. The pump rate is adjusted to maintain an outlet temperature of 100 ±1 °C.Example 5: Spray drying of rhamnolipids with soda (80 / 20), not according to the inventionA suspension with a solid content of 20 wt.-% was produced for spray drying. The solids consisted of 80 wt.-% rhamnolipids and 20 wt.-% soda. Therefore, water and the rhamnolipid solution were mixed (50 wt.-% rhamnolipid content) and soda was dissolved at RT (25 °C) in this mixture under stirring with a magnetic stirrer for 30 min. Spray drying was carried out using the Mini Spray Dryer B-290 (Buchi Labortechnik AG, Flawil, Switzerland) equipped with a two-fluid nozzle. During spray drying, the suspensions were kept agitated by means of a magnetic stirrer bar. The inlet temperature was set at 150 °C and kept constant throughout the process. The atomization nitrogen flow rate and drying air volumetric flow rate were adjusted to -750 L / h and 35 m3 / h, respectively. The pump rate was adjusted to maintain an outlet temperature of 100±1 °C. After spray drying, the samples were collected from the product collection vessel and stored in sealed glass containers to prevent subsequent moisture uptake.Example 6: Spray drying of rhamnolipids with alginate, not according to the inventionA suspension with a solid content of 20 wt.-% was produced for spray drying. The solids consisted of 80 wt.-% rhamnolipids and 20 wt.-% alginate. Therefore, water and the rhamnolipid solution were mixed (50 wt.-% rhamnolipid content) and alginate was dissolved at RT (25 °C) in this mixture under stirring with a magnetic stirrer for 30 min. Spray drying of the suspension was not possible with the Mini Spray Dryer B-290 (Buchi Labortechnik AG, Flawil, Switzerland), because the viscosity was too high for the peristaltic pump.Example 7: Free-flowing propertiesThe powders produced by spray drying were stored at RT (25 °C) in sealed glass containers over eight weeks. The sample consisting of rhamnolipids with maltodextrin (80 / 20) remained as a flowing powder, whereas the sample consisting of rhamnolipids with soda (80 / 20) strongly agglomerated within the first few days and formed a caked powder lump.Example 8: Re-dissolving properties in waterThe samples were tested in terms of their re-dissolving properties in water by dissolving 5 wt.-% of powder in cold water under stirring using a magnetic stirrer. Samples of the example 1 and dissolved very quickly under these conditions in ~60 s. Samples of example 3 took significantly longer to dissolve in water (3-5 min).Example 9: Foaming properties in waterThe foaming properties of the samples were tested by dissolving 1 g powder in 20 mL water and then agitating the solution for 0.5 min in a mixing cylinder (50 mL, tall form, BLAUBRAND®, class A). The height of the foam level is then determined, as well as the foam stability over 5 min, examples are given in the table for samples of example 2 and example 3. The initial foam hight of samples of example 3 is higher compared to samples of example 1 and 2, but the foam stability is significantly higher in the latter compared to the prior. The foam of samples of example 1 and 2 contains smaller and more uniform pores compared to samples of example 3, in which bubbles coalesce rapidly leading to a fast collapse of the foam. In the foam of samples of example 1 and 2 only few coalescence events occur and thereby the foam height only slightly decreases over 5 min.Example 10: Spray drying of rhamnolipids with maltodextrin (80 / 20), according to the inventionA suspension with a solid content of 20 wt.-% was produced for spray drying. The solids consisted of 80 wt.-% rhamnolipids and 20 wt.-% maltodextrin (DE 12). Therefore, water and the rhamnolipid solution were mixed (50 wt.-% rhamnolipid content) and maltodextrin was dissolved at RT (25 °C) in this mixture under stirring with a magnetic stirrer for 30 min. Spray drying was carried out using the Mini Spray Dryer B-290 (Buchi Labortechnik AG, Flawil, Switzerland) equipped with a two-fluid nozzle. During spray drying, the suspensions were kept agitated by means of a magnetic stirrerbar. The inlet temperature was set at 150 °C and kept constant throughout the process. The atomization nitrogen flow rate and drying air volumetric flow rate were adjusted to -750 L / h and 35 m3 / h, respectively. The pump rate was adjusted to maintain an outlet temperature of 75±1 °C. After spray drying, the samples were collected from the product collection vessel and stored in sealed glass containers to prevent subsequent moisture uptake.Example 11: Spray drying of rhamnolipids with Octenyls uccinat (80 / 20), not according to the inventionA suspension with a solid content of 20 wt.-% was produced for spray drying. The solids consisted of 80 wt.-% rhamnolipids and 20 wt.-% Octenylsuccinat. Therefore, water and the rhamnolipid solution were mixed (50 wt.-% rhamnolipid content) and Octenylsuccinat was dissolved at RT (25 °C) in this mixture under stirring with a magnetic stirrer for 30 min. Spray drying was carried out using the Mini Spray Dryer B-290 (Buchi Labortechnik AG, Flawil, Switzerland) equipped with a two-fluid nozzle. During spray drying, the suspensions were kept agitated by means of a magnetic stirrer bar. The inlet temperature was set at 150 °C and kept constant throughout the process. The atomization nitrogen flow rate and drying air volumetric flow rate were adjusted to -750 L / h and 35 m3 / h, respectively. The pump rate was adjusted to maintain an outlet temperature of 75±1 °C. After spray drying, the samples were collected from the product collection vessel and stored in sealed glass containers to prevent subsequent moisture uptake.Example 12: Product yield in spray dryingThe product yield obtained in the spray drying process was determined for example 10 and 11 . Therefore, the weight of the product obtained after the cyclone was measured and the yield was calculated based on total solid content used in the process. Surprisingly, the yield of example 10 was 10% higher compared to example 11 .Example 13: Re-dissolving properties in waterExample 10 and 11 were tested in terms of their re-dissolving properties in water by dissolving 5 wt.-% of powder in cold water under stirring using a magnetic stirrer. Example 10 dissolved very quickly under these conditions in -60 s ~, whereas example 11 showed significantly poorer redissolving properties and took significantly longer to dissolve in water (3-5 min).Example formulationsEach of the following example formulations was prepared four times: As “Composition A” example 1 , 2, 3 and 4 was used in distinct formulations.Example formulation 1: Shower ScrubExample formulation 2 Cellulose ScrubExample formulation 3: Exfoliating Body ScrubExample formulation 4: Dry ShampooExample formulation 5: Dry ShampooExample formulation 6: Shower ScrubExample formulation 7: Cellulose ScrubExample formulation 8: Exfoliating Body ScrubExample formulation 9: Washing PowderExample formulation 10: Washing PowderExample formulation 11: Powder CleanserExample formulation 12: Powder CleanserExample formulation 13: SoapExample formulation 14: Bath BombExample formulation 15: Bath BombExample formulation 16: Bath SaltExample formulation 17: Bath SaltExample formulation 18: ToothpasteExample formulation 19: ToothpasteExample formulation 20: ToothpasteExample formulation 21: ToothpasteExample formulation 22: ToothpasteExample formulation 23: ToothpasteExample formulation 24: ToothpasteExample formulation 25: ToothpasteExample formulation 26: ToothpasteExample formulation 27: ToothpasteExample formulation 28: ToothpasteExample formulation 29: ToothpasteExample formulation 30: ToothpasteExample formulation 31: ToothpasteExample formulation 32: ToothpasteExample formulation 33: ToothpasteExample formulation 34: ToothpasteExample formulation 35: ToothpasteExample formulation 36: ToothpasteExample formulation 37: ToothpasteExample formulation 38: ToothpasteExample formulation 39: ToothpasteExample formulation 40: ToothpasteExample formulation 41: ToothpasteExample formulation 42: ToothpasteExample formulation 43: ToothpasteExample formulation 44: ToothpasteExample formulation 45: ToothpasteExample formulation 46: ToothpasteExample formulation 47: ToothpasteExample formulation 48: Toothpaste for KidsExample formulation 49: Toothpaste for ChildrenExample formulation 50: Baby ToothpasteExample formulation 51: Toothpaste for ChildrenExample formulation 52: Kids ToothpasteExample formulation 53: 2 in 1 Toothpaste + MouthwashExample formulation 54: 2 in 1 Toothpaste + MouthwashExample formulation 55: Mouthwash TabsExample formulation 56: Tooth TabExample formulation 57: Powder ToothpasteExample formulation household care 1: solid HDW formulationExample formulation household care 2: solid HDW formulationExample formulation household care 3: solid HDW formulationExample formulation household care 4: solid All Purpose CleanerExample formulation household care 5: solid Glass CleanerExample formulation household care 6: Glass Cleaner Power TabExample formulation household care 7: Glass Cleaner Power TabExample formulation household care 8: Coffee machine descalersExample formulation household care 9: solid Kitchen CleanerExample formulation household care 10: solid Rim BlockExample formulation household care 11: solid Rim BlockExample formulation household care 12: solid Rim BlockExample formulation household care 13: solid Bathroom CleanerExample formulation household care 14: solid Bathroom CleanerExample formulation household care 15: Powder Detergent SensitivExample formulation household care 16: Powder DetergentExample formulation household care 17: Powder Detergent NaturalExample formulation household care 18: Powder DetergentExample formulation household care 19: Powder Color Detergent

Claims

Claims1 . Spray-drying process of biosurfactants comprising the steps ofA) providing a liquid starting composition comprising water and at least one biosurfactant,B) adding maltodextrin to the starting composition,C) spray-drying the water, biosurfactant and maltodextrin comprising composition characterized in that said biosurfactant is comprised in an amount of from 5.0 wt.-% to 60.0 wt.-%, preferably from 10.0 wt.-% to 55.0 wt.-%, more preferably from 15.0 wt.-% to 50.0 wt.- %, and that said maltodextrin is comprised in an amount of 0.2 wt.-% to 30.0 wt.-%, preferably 0.5 wt. % to 20 wt.-%, more preferably 0.75 wt.-% to 12.0 wt.-%, wherein the weight percentages refer to the sum of the total starting composition and maltodextrin.

2. Process according to claim 1 , characterized in that said biosurfactant is selected from rhamnolipids, glucolipids and sophorolipids, preferably rhamnolipids and glucolipids, most preferably rhamnolipids.

3. Process according to claim 1 or 2, characterized in that maltodextrin is added in an amount, that the weight ratio of biosurfactant and maltodextrin is in the range of from 5:1 to 35:1 , preferably from 8:1 to 30:1 , more preferably from 10:1 to 28:1 , most preferably from 15:1 to 25:1.

4. Process according to any of the preceding claims, characterized in that said added maltodextrin has a dextrose equivalent from 2 % to 30 %, preferably 3 % to 22 %, more preferably 4 % to 8 %.

5. Process according to any of the preceding claims, characterized in that said liquid starting composition comprises water in an amount of 20 wt.-% to 98 wt.-%, preferably from 40 wt.-% to 95 wt.-%, more preferably from 60 wt.-% to 90 wt.-%, wherein the weight percentages refer to the total liquid starting composition.

6. Process according to any of the preceding claims, characterized in that the water, biosurfactant and maltodextrin comprising composition in process step C) has a total solid content of from 6.0 wt.-% to 80.0 wt.-%, preferably from 12.0 wt.-% to 60.0 wt.-%, more preferably from 16.0 wt.-% to 40.0 wt.-%.

7. Process according to any of the preceding claims, characterized in that in process step C) a drying gas, preferably selected from nitrogen and air, at a temperature from 120 °C to800 °C, preferably from 130 °C to 400 °C, more preferably from 140 °C to 170 °C, is used.

8. Process according to any of the preceding claims, characterized in that in process step C) an outlet temperature from 50 °C to 100 °C, preferably from 55 °C to 90 °C, more preferably from 60 °C to 80 °C, is used.

9. Process according to any of the preceding claims, characterized in that in process step C) a pressure nozzle or a two-substance nozzle is used.

10. Composition comprising at least one biosurfactant and maltodextrin obtainable by a process to any of the preceding claims.11 . Solid composition comprising at least one biosurfactant, and maltodextrin.

12. Composition according to claim 10 or 11 , characterized in that said biosurfactant is selected from rhamnolipids, glucolipids and sophorolipids, preferably rhamnolipids and glucolipids, most preferably rhamnolipids.

13. Composition according to any of the claim 10 to 12, characterized in that it comprises60 wt.-% to 95 wt.-%, preferably 70 wt.-% to 90 wt.-%, more preferably 75 wt.-% to 85 wt.-%, of said at least one biosurfactant, and5.0 wt.-% to 40 wt.-%, preferably 10 wt.-% to 30 wt.-%, more preferably 15 wt.-% to 25 wt.- %, maltodextrin. wherein the weight percentages refer to the total composition.

14. Composition according to any of the claim 10 to 13, characterized in that it has a mean particle size of from 4.0 pm to 200 pm, preferably from 6.0 pm to 100 pm, more preferably from 8.0 pm to 50 pm.

15. Composition according to any of the claim 10 to 14, characterized in that it has a residual water content of from 1 .0 wt.-% to 10.0 wt.-%, preferably from 2.0 wt.-% to 8.0 wt.-%, more preferably from 3.0 wt.-% to 6.0 wt.-%, wherein the weight percentages refer to the total composition.

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