Abstract:
A foodstuff particulate lipid composition comprises a particulate solid non-lipid carrier and an oil-in-water emulsion on the carrier capable of being released from the carrier on contact with aqueous media to form an oil-in-water emulsion in said aqueous media. Also disclosed is the use of the composition and a process for its manufacture.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a foodstuff particulate lipid composition. More specifically, the invention relates to a foodstuff particulate lipid composition comprising a non-lipid carrier, its use, and a method for its manufacture. 
       BACKGROUND OF THE INVENTION 
       [0002]    Oil-in-water emulsions for human consumption are widely used in the foodstuff industry. Due to their heterogeneous nature all emulsions are basically unstable. A frequent problem with such emulsions is physical storage stability, another microbial degradation. Their often high content of water is problematic also from a transport perspective by adding substantive weight to the respective product, thereby increasing transport and storage costs. Therefore the respective oil-in-water emulsion is usually prepared a short time before it is used rather than stored for an extended period of time. 
       OBJECTS OF THE INVENTION 
       [0003]    The present invention seeks to overcome one or several of the aforementioned problems by providing a means for preparing an oil-in-water emulsion, which means is stable for long-term storage and can be easily handled in standard and non-standard industrial processes used in the foodstuff industry or even by a consumer. 
         [0004]    Further objects of the invention will be apparent from the following summary of the invention, the description of preferred embodiments thereof, and the appended claims. 
       SUMMARY OF THE INVENTION 
       [0005]    According to the present invention is provided a foodstuff particulate lipid composition comprising a particulate solid non-lipid carrier and an oil-in-water emulsion on the carrier capable of being released from the carrier on contact with aqueous media to form an oil-in-water emulsion in said aqueous media. 
         [0006]    According one preferred aspect of the invention the particle size of the composition of the invention is determined by the particle size of the carrier, the composition substantially consisting of particles, each comprising a single carrier particle to which oil-in-water emulsion adheres. 
         [0007]    According to another preferred aspect of the invention the particle size of the composition of the invention is determined by the capability of two or more particles, each comprising a single carrier particle to which oil-in-water emulsion adheres, to form larger aggregates. 
         [0008]    It is preferred for the particulate lipid composition of the invention to be free-flowing so as to be capable of being processed in equipment used in the foodstuff industry. 
         [0009]    According to a basic aspect of the invention the mean weight of the particles of the composition of the invention is preferably 10 mg or lower, more preferred 1 mg or lower, most preferred 0.1 mg or lower. 
         [0010]    According to an alternative basic aspect of the invention carrier particles of a lager size are used such as, for instance, oat or corn flakes, to bring the mean weight of the particles of the composition of the invention to more than 5 mg or 10 mg or even 50 mg. 
         [0011]    An important aspect of the invention is that the carrier must not dissolve in the oil-in-water emulsion or otherwise be substantially affected by it, this being a condition for the oil-in-water emulsion to be preserved substantially unchanged for storage and for release in contact with aqueous media 
         [0012]    The oil-in-water emulsion of the invention comprises a non-polar lipid and a lipidic emulsifier. Suitable oil-in-water emulsions including non-polar lipids and lipidic emulsifiers for incorporation into the composition of the invention are disclosed in U.S. Pat. Nos. 6,517,883 (Herslöf et al.), 6,355,693 (Herslöf et al.), and 5,688,528 (Carlsson et al.), which are hereby incorporated for reference. According to an advantages aspect of the invention the oil-in-water emulsion may comprise nutrients, such as arginine or cysteine; vitamins, such as vitamin A; antioxidant; colourant; flavouring. 
         [0013]    The non-polar lipid of the invention is preferably a triglyceride, which is solid, semi-solid, or liquid at room temperature, selected from natural, semi-synthetic and synthetic oil. Natural oils are preferably based on the combination of mainly, that is, to more than 90% by weight, preferably to more than 95% by weight, palmitic, oleic, linoleic, linolenic, and stearic esters of glycerol are preferred. Most preferred is palm oil and its equivalent confectionery fats, such as coconut oil, palm kernel oil, cocoa butter; partially hydrogenated soybean oil; partly hydrogenated rapeseed oil; sunflower oil and its equivalent liquid vegetable oils, such as soybean oil, rapeseed oil, safflower oil, olive oil, corn oil, groundnut oil, linseed oil, rice bran oil, and sesame oil; animal fats and oils, such as fish oil, butter fat, lard, tallow, their fractions and mixtures thereof. The weight ratio of non-polar lipid to emulsifier is preferably from 6:1 to 60:1, more preferred from 10:1 to 30:1. 
         [0014]    The lipidic emulsifier of the invention can be of natural or synthetic, including semi-synthetic, origin. Particularly preferred are emulsifiers selected from mono- and diglycerides, in particular of lauric, myristic, palmitic, stearic, oleic, linoleic, and linolenic acid, their mixtures and acid esters, in particular their acetates; sorbitan esters and polysorbates; polyglycerol esters; sucrose esters; propylene glycol mono fatty acid esters; esters of lactic acid, succinic acid, fruit acid; lecithins; specific membrane lipids, such as phospholipids, galactolipids, and sphingolipids. The emulsifier of the invention is preferably selected from phospholipids containing material, such as soy lecithin, and galactolipid containing material, such as fractionated oat oil, of which galactolipid material is most preferred. A preferred galactolipid material comprises 20% by weight to 30% by weight of galactolipids, mainly digalactodiacylglycerol, and from 10% by weight to 15% by weight of other polar lipids. 
         [0015]    The carrier of the invention is preferably selected from foodstuff of vegetable, animal or mixed origin. Preferably the carrier is capable of passing at least the upper part of the gastro-intestinal tract substantially unchanged. According to on preferred aspect, the carrier of the invention is preferably substantially insoluble in water but may swell in contact with water. According to an alternative preferred aspect, the carrier of the invention is partially or fully soluble in water. Preferred carriers are comprised by the group consisting of starch, modified starch, proteinaceous material such as whey protein, soy protein and casein, other material of vegetable origin such as material originating from oat bran, rice hulls, ground seeds, etc., gums such as gum arabic, pectins, xanthans, and carrageenans. In addition to organic carrier materials inorganic carrier materials used in the foodstuff industry, such as sodium chloride, calcium carbonate, and calcium phosphate, may be used in certain applications. It is also within the scope of the invention to use mixtures of the carrier materials of the invention. In principle, any edible solid particulate carrier material that does not interact, at least not to a substantial degree, with the oil-in-water emulsion in an irreversible manner preventing it from being released on contact with aqueous media to form an oil-in-water emulsion in said aqueous media may be used. 
         [0016]    It is preferred for the composition of the invention to comprise from 0.1% by weight to 90% by weight of oil-in-water emulsion and from 10% to 99.9% by weight of carrier; more preferred from 0.5% by weight to 60% by weight of oil-in-water emulsion and from 99.5% by weight to 40% by weight of carrier; even more preferred from 0.5 by weight to 40% by weight, most preferred to 30% by weight of oil-in-water emulsion and from 60% by weight, most preferred from 70% by weight, to 99.5 by weight of carrier. 
         [0017]    The term aqueous media as used herein comprises water, aqueous solutions of salts such as sodium chloride and/or of organic compounds such as glucose and/or fructose but also aqueous suspensions and/or emulsions of organic material, such as skimmed milk and even gastric fluids. It is preferred for the composition to release more than 50% by weight, more preferred more than 75% by weight, of its oil-in-water emulsion on contact with an aqueous media at a temperature of below 75° C., more preferred of below 50° C., more preferred of below 40° C., most preferred at about 35° C. 
         [0018]    According to an additional preferred aspect of the invention the mean particle size (number average) of the emulsion formed by contact of the composition of the invention with an aqueous media exceeds that of the emulsion used for preparing the composition of the invention on contact with the same media by less than 30%, preferably by less than 15%, most preferred by less than 10%. 
         [0019]    According to the present invention is also disclosed a method of producing a foodstuff particulate lipid composition that comprises a particulate solid non-lipid carrier and an oil-in-water emulsion on the carrier capable of being released from the carrier on contact with aqueous media to form an oil-in-water emulsion in said aqueous media. The method comprises the steps of: (a) providing an oil-in-water emulsion in liquid form; (b) providing a particulate solid non-lipid carrier; (c) adding the oil-in-water emulsion to the carrier over a period of time while agitating the carrier to obtain said particulate lipid composition. It is preferred for oil-in-water emulsion to be provided at a temperature of from 30° C. to 75° C. It is also preferred to cool the carrier and the product formed from the carrier during addition of the emulsion so as to keep its temperature below 30° C. The method of the invention may comprise the additional step of: (d) separating a fraction of defined particle size from said particulate lipid composition by, for instance, sieving. 
         [0020]    The composition of the invention can be used in the manufacture of a foodstuff. In particular it can be used for enriching a foodstuff by adding a portion of the composition of the invention to the foodstuff followed by mixing. Alternatively the composition of the invention as such can be used as a foodstuff. 
         [0021]    Also disclosed is a foodstuff comprising the composition of the invention; the foodstuff may be one intended for mixing with an aqueous media, such as skimmed milk, prior to consumption. The edible oil-in-water emulsion obtained thereby is also comprised by the scope of the invention. 
         [0022]    Furthermore disclosed is a process for the manufacture of an edible oil-in-water emulsion comprising contacting the composition of the invention with an aqueous media, for instance one comprising carbohydrate and/or peptide material dissolved therein. This process is preferably conducted at a temperature of 35° C. or higher. 
         [0023]    The invention will now be described in more detail in form of a number of non-limiting embodiments. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0024]    Exemplary non-lipid carrier materials. A number of exemplary non-lipid carrier materials available on the market are listed in Table 1. 
         [0000]    
       
         
               
             
               
               
               
             
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Non-lipid carrier materials 
               
             
          
           
               
                   
                 Non-lipid carrier material 
                 Supplier 
               
               
                   
                   
               
             
          
           
               
                 A 
                 Calcium caseinate I, Art. No. 1585 
                 DMV International 1   
               
               
                 B 
                 Whey protein 65% 
                 Arla Foods 2   
               
               
                 C 
                 Isolated soy protein 066-974. PRO-FAM 
                 ADM 3   
               
               
                   
                 974 
               
               
                 D 
                 Pectin B, Rapid set, Art. No. 7204 
                 CPKelco 4   
               
               
                 E 
                 Guar Gum, Ceramel, Art. No. 7450 
                 Swissgum 5   
               
               
                 F 
                 Xanthan, Keltrol RD, Art. No. 2107 
                 CPKelco 
               
               
                 G 
                 Microcrystalline cellulose, Avicel-Plus 
                 FMC 6   
               
               
                   
                 CM 2159, Batch no. C 14731 
               
               
                 H 
                 Lambda-Carrageenan, Viscarin GP 209F, 
                 FMC 
               
               
                   
                 Lot no. 3091204B 
               
               
                 I 
                 IotaCarrageenan, Viscarin SD, Lot no. 
                 FMC 
               
               
                   
                 30818040 
               
               
                 K 
                 Waxy maize, Amioca powder, Batch no. 
                 National Starch &amp; 
               
               
                   
                 GDT 703 
                 Chemical 7   
               
               
                 L 
                 Corn starch, Purity 826 LBI 6545 
                 National Starch &amp; 
               
               
                   
                   
                 Chemical 
               
               
                 M 
                 Potato starch, Art. no. 94441.1 
                 Carl Roth GmbH &amp; 
               
               
                   
                   
                 Co. 8   
               
               
                 N 
                 Wheat starch, Art. No. 21 146.290, lot 
                 VWR 9   
               
               
                   
                 no. M344 
               
               
                   
               
               
                   1 Veghel, Netherlands; 
               
               
                   2 Stockholm, Sweden; 
               
               
                   3 Decatur, IL, U.S.A.; 
               
               
                   4 Lille Skensved, Denmark; 
               
               
                   5 Kreuzlingen, Switzerland; 
               
               
                   5 Philadelphia, PA, U.S.A.; 
               
               
                   6 Bridgewater, NJ, U.S.A.; 
               
               
                   7 Karlsruhe, Germany; 
               
               
                   8 West Chester, PA, U.S.A. 
               
             
          
         
       
     
       Example 1 
       [0025]    Exemplary method of preparing the composition of the invention. An oil-in-water lipid emulsion for use in the invention is prepared by mixing weighed amounts of an oil such as palm oil, an emulsifier such as fractionated oat oil, and water with a powerful mechanical mixer such as a T 18 ULTRA-TURRAX® (IKA Werke GmbH &amp; Co. KG, Staufen, Germany). A oil-in-water lipid emulsion of this kind is available on the market (Olibra®; 40% palm oil, 2% fractionated oat oil, in water; Lipid Technologies Provider AB, Karlshamn, Sweden). A weighed amount of the emulsion is added dropwise to a weighed amount of the carrier in a glass flask while gently shaking the flask in intervals. At the end of addition the mixture is stirred with a spatula until apparent homogeneity. 
       Example 2 
       [0026]    Test of the load capacity of carriers of the invention loaded with the oil-in-water emulsion of the invention. A number of compositions of the invention were prepared by loading each of the exemplary carriers with increasing amounts of Olibra® oil-in-water emulsion of Example 1. The flowability of the compositions of the invention thus prepared was assessed visually according to the following scale: 6=fine powder; 5=fine powder containing larger aggregates (small lumps); 4=sticky powder; 3=mixture of powder and large lumps; 2=large sticky lumps; 1=smear. 
         [0027]    The results the load tests are shown in Table 2. 
         [0000]    
       
         
               
             
               
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
             
             
               
                   
               
               
                 Exemplary load capacity of carriers according to the 
               
               
                 invention 
               
             
          
           
               
                   
                 Olibra, % by weight 
               
             
          
           
               
                   
                 Carrier 
                 30 
                 40 
                 50 
                 60 
                 70 
                 80 
               
               
                   
                   
               
             
          
           
               
                   
                 A 
                 Ca-caseinate 
                 6 
                 6 
                 6 
                 5 
                 1 
                 1 
               
               
                   
                 B 
                 Whey protein 
                 6 
                 1 
                 1 
                 1 
                 1 
                 1 
               
               
                   
                 C 
                 Soy protein 
                 6 
                 6 
                 6 
                 6 
                 1 
                 1 
               
               
                   
                 D 
                 Pectin 
                 6 
                 6 
                 6 
                 2 
                 1 
                 1 
               
               
                   
                 E 
                 Guar Gum, 
                 6 
                 6 
                 6 
                 4 
                 3 
                 1 
               
               
                   
                 F 
                 Xanthan 
                 6 
                 4 
                 3 
                 2 
                 1 
                 1 
               
               
                   
                 G 
                 Microcrystalline 
                 6 
                 6 
                 6 
                 3 
                 1 
                 1 
               
               
                   
                   
                 cellulose 
               
               
                   
                 H 
                 Lambda 
                 6 
                 6 
                 5 
                 3 
                 1 
                 1 
               
               
                   
                   
                 Carrageenan 
               
               
                   
                 I 
                 Iota-Carrageenan 
                 6 
                 6 
                 5 
                 3 
                 1 
                 1 
               
               
                   
                 K 
                 Waxy maize 
                 6 
                 5 
                 2 
                 1 
                 1 
                 1 
               
               
                   
                 L 
                 Corn starch 
                 6 
                 6 
                 6 
                 1 
                 1 
                 1 
               
               
                   
                 M 
                 Potato starch 
                 5 
                 1 
                 1 
                 1 
                 1 
                 1 
               
               
                   
                 N 
                 Wheat starch 
                 5 
                 1 
                 1 
                 1 
                 1 
                 1 
               
               
                   
                   
               
             
          
         
       
     
       Example 3 
       [0028]    Effect of carrier on release temperature. Four compositions of the invention comprising an Olibra®-type oil-in-water emulsion of 26% of palm oil and 2% of fractionated oat oil were prepared by the method in Example 1. The compositions were allowed to equilibrate for 24 h. After dispersing 0.5 g each in 4.5 ml deionized water the release of emulsion particles from the composition into the deionized water was followed over a temperature range of from 20° C. to 50° C. in intervals of 10° C. and confirmed by light microscopy. The results demonstrate that the (threshold) release temperature of emulsion particles depends, i.a., on the nature of the carrier. 
       Example 4 
       [0029]    Particle size distribution. A composition of the invention was prepared by the general method of Example 1 by adding the Olibra®-type oil-in-water emulsion of 26% of palm oil and 2% of fractionated oat oil of Example 3 was to whey protein (exemplary carrier B) in an amount to make the composition (free-flowing powder) contain 27% by weight of the emulsion. The composition was allowed to equilibrate for 24 h. The composition (0.5 g) was dispersed in 4.5 ml deionized water at room temperature (B) and compared to a correspondingly prepared aqueous dispersion (A) of the original oil-in-water emulsion with respect to particle size distribution (Figure). This demonstrates that, after addition of the original emulsion to a carrier, a substantial portion of lipid particles released into an aqueous media has about the same size distribution than in the original emulsion; less than 40% by weight of the lipid particles have undergone some degree of coalescence. 
       Example 5 
       [0030]    Effect of emulsifier on the stability of air-dried or deep-frozen compositions of the invention. Three oil-in-water emulsions were prepared by the general process of Example 1, all containing 28% by weight of oil phase (26% of palm oil, 2% of emulsifier):
   (a) Palm oil/fractionated oat oil (Lipid Technologies Provider AB, Karlshamn, Sweden; with chemical composition ‘a’;   (b) Sunflower oil (Zeta®, marketed in Sweden by Di Luca &amp; Di Luca AB, Stockholm)/fractionated oat oil (Lipid Technologies Provider AB, Karlshamn, Sweden);
       with chemical composition ‘b’;   
       (c) Sunflower oil (Zeta®, marketed in Sweden by Di Luca &amp; Di Luca AB, Stockholm)/Soy lecithin emulsifier (Leciprime 1000 IP, Cargill, Inc., Minneapolis, Minn., U.S.A.); with chemical composition ‘c’.   
 
         [0035]    The emulsions (a)-(c) were mixed with whey protein (exemplary carrier B) in a weight ratio of 27 to 73 for compositions of the invention (a*)-(c*), respectively. A portion of each composition (a*)-(c*) was stored at room temperature in closed containers (a*′)-(c*′), another portion was heated in an oven to 40° C. for four hours and then stored at room temperature in closed containers (a*″)-(c*″), and a third portion in closed containers (a*′″)-(c*′″) was kept at −22° C. for 24 h in closed containers followed by storage at room temperature in the same containers. A portion of each of the powders was dispersed in deionised water (4.5 g) at room temperature. The particle size of the released emulsions was determined by a Mastersizer 2000 instrument (Malvern Instruments Ltd., Malvern, UK). The results are shown in Table 5; d (0.5)  represents the arithmetic number mean size of the lipid particles in nm. 
         [0000]    
       
         
               
             
               
               
             
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 3 
               
             
             
               
                   
               
               
                 Arithmetic number mean size of lipid particles 
               
               
                 released from the composition of the invention and the oil-in- 
               
               
                 water emulsion used for its preparation 
               
             
          
           
               
                   
                 d (0.5) , nm 
               
               
                   
                 Chemical composition 
               
             
          
           
               
                   
                 Sample 
                 ‘a’ 
                 ‘b’ 
                 ‘c’ 
               
               
                   
                   
               
             
          
           
               
                   
                 Original emulsion (a) − (c) 
                 275 
                 304 
                 367 
               
               
                   
                 Composition (a*′) − (c*′) 
                 310 
                 458 
                 553 
               
               
                   
                 Composition after drying 
                 308 
                 566 
                 1787 
               
               
                   
                 (a*″) − (c*″) 
               
               
                   
                 Composition after freezing 
                 435 
                 578 
                 1890 
               
               
                   
                 (a*″′) − (c*″′) 
               
               
                   
                   
               
             
          
         
       
     
         [0036]    The results in Table 3 demonstrate the usefulness of various oils and emulsifiers for preparing the composition of the invention. The superiority of a galactolipid (fractionated oat oil) emulsifier over a phospholipid (soy lecithin) emulsifier is also demonstrated, especially in regard of drying and freezing stability. 
       Example 6 
       [0037]    Effect of an oil-in-water emulsion of the composition of the invention containing a hydrocolloid. Two compositions of the invention were prepared by the general method of Example 1 by adding an oil-in-water emulsion of 20% by weight of rapeseed oil (purchased from the retail market), 4% by weight of fractionated oat oil of Example 3, and 2% by weight of Glucagel (Polycell Technologies, Crookston, Minn., USA; containing 75% by weight of beta-glucan) to whey protein (exemplary carrier B) and calcium caseinate (exemplary carrier A) respectively. In both cases the proportion of emulsion to carrier (w/w) was 20:80. 
         [0038]    The powders were easily dispersed in deionised water at ambient temperature. The dispersions were smooth without lumps and had higher viscosities compared to dispersions with only caseinate or whey protein. The released emulsion particles were observed by means of optical microscopy. 
       Example 7 
       [0039]    Odour masking. Four compositions of the invention were prepared by the general method of Example 1 by adding an oil-in-water emulsion of 40% by weight of fish oil (EPAX 3000; ProNova Biocare, Norway) and 5% by weight of fractionated oat oil of Example 3 to four carriers: whey protein (exemplary carrier B), soy protein (exemplary carrier C), corn starch (exemplary carrier L) and microcrystalline cellulose (exemplary carrier G). 
         [0040]    While the emulsion had a slight but typical odour of fish oil, the powderous solid compositions of the invention were practically odour-free. After a week in a refrigerator none of the powders exhibited a fish oil odour. 
         [0041]    Each of the four compositions of this Example was separately treated with 4 g of membrane filtered water at ambient temperature (about 20° C.). In the products no fish oil odour could be detected.