SPREADABLE FAT PRODUCT AND METHOD FOR ITS PRODUCTION

Abstract: Fat product which is spreadable at refrigerator temperature and contains 35-55% fat, 4-7% protein and 41-58% water. The protein has been obtained from an ultra-filtrated milk product, at which the fat product after mixing the protein concentrate with the fat raw material and homogenization of the fat spheres consists of a stable oil-in-water emulsion. The emulsion is stabilized by the milk protein. The fat product is free from additives in the form of stabilizing agents and emulsifiers. The method to manufacture the fat product is seen from the attached flow-chart, which shows the steps in the process.

Description: Spreadable fat product and method for its production. The present invention relates to a fat product, which is spreadable at a refrigerator temperature and contains 35-55% fat, 4-7% protein and 41-58% water- It is known since long to produce different spreadable fat products with a low fat content in order to meet a consumer interest in products with a low calory con¬ tent. The manufacture of such products are described e.g. in SE 393 253, which describes a fat emulsion of the type water-in-oil with a low calory content and a high content of protein. This fat emulsion is pro¬ duced from milk, which milk is membrane filtrated,after which the protein concentrate is heat treated before it is forced to emulsify in a fat phase, at which there is obtained a water-in-oil emulsion. Also through a USSR-publication 645 640 there is known to manufacture a fat product with a low fat content and a high protein content. The protein concentrate is obtained by ultra- filtration of skim milk, which is mixed with cream after which the mixture is churned. At that a water-in-oil emulsion is produced. The two fat products described above consist of water- in-oil emulsions, which are the most common type of emulsion for both margarine, butter and margarine with a reduced fat content. It is known per εe to manufacture fat products also in form of oil-in-water emulsions. A study of such emul¬ sions is shown in the, Canadian Dairy and Ice Cream Jour¬ nal 45 (1966) :1, where there is decribed a fat product where the milk protein consists cf calcium-reduced skim milk powder. The skim milk powder is reconstituted in water and mixed at high speed with at.Owing to the reduced calcium content the skim milk powder is made more absorbent. Any product of this type is not avail¬ able on the market to-day, which may depend on the fact that the chemical. change of the caseinate has resulted in a taste of the fat product which has not been accepted by the consumers. Another fat product, which consists of an oil-in-water emulsion, is described in the Australian Patent Publi¬ cation 498 980. In this product the fat phase consists of milk fat and animal or vegetable fat mixed with a water phase, containing a stabilizing agent such as soj meal, gelatine or modified starch. According to the invention, there is now proposed a new spreadable fat product, which combines characteri¬ zing features rom fat products earlier known in a new manner. The proposed fat product contains protein which is obtained by ultra-filtration cf a rrά-Lk product, which protein concentrate after mixing with a fat raw mate¬ rial and breaking up the fat in small spheres constitutes a stable oil-in-water emulsion, which emulsion is stabilized by the milk protein, which fat product is free from additives in the form of stabi¬ lizing agents and emulsifiers. It has been found that this product, where the protein source consists of an ultra-filtrated milk is considered better regarding to taste than fat products, in which conventional pro¬ tein sources as milk powder and condensed milk are in¬ cluded. The latter contains lactose, which gives the products a taste of melt cheese. The fat raw material - may consist both of milk fat - ϋϊ r^l *-. r - C.-.FI and fat from another origin. Even when the fat consists of milk fat the product has an excellent spreadability at refrigerator temperature. The continuous phase in an emulsion determines the characteristics of the emulsion. A product of milk fat where the fat con¬ stitutes a continuous phase is not spreadable at refri¬ gerator temperature. The crystals of the fat form a network, where the number of crystals determines the hardness of the product. When the product is warmed some of the crystals melt and the fat becomes softer. Our product consists of a number of small drops or spheres of fat, which certainly contain crystallized fat, but the small spheres glide and roll upon each other in such a way that the product is still soft anyhow. These little fat spheres are achieved by homogenization. According to the invention a spread¬ able product is obtained, which contains only milk fat and this is a great advantage in many countries, where it is forbidden to sell products which contain milk fat mixed with another fat. The structures are shown in fig. 3. The fat product has also a superior shelf life even if it.-is manufactured as a " nature product " i.e. completely without any additives in the form of erπulsi- fiers and stabilizing agents. The milk protein forms a protein shell around the fat drops in the emulsion and the emulsion remains stable for a long time. At a reduced fat content an increased amount of protein is needed, since the amount of water increases at the same time and more protein is needed to bind the water'in:: he form"of? a gel. At a fat content of 35% there is needed 7% of protein, while at a fat content of 55% only 4% of protein is needed to make the product stable. The limits given in the first part of the main claim for the fat content are due to consumer viewpoints. A fat product with a fat content below 35% tastes like a melt cheese, while a fat product with a higher fat content than 55% cannot be considered as a fat product with a re¬ duced calory content. The proposed fat product is rranufactured frommilk, a milk product with or without fat, which is pasteurized at 85r-95°C, ultra-filtrated after cooling in order to achieve a concentration of pro¬ tein and a diirriz shing of the lactose content simultaneously, after which the concentrate enriched in protein is mixed with the fat raw material and homogenized at 40-70°C in order to form a stable oil-in-water emulsion. With the expression "ho ogenization" we do not only mean giving the product a homogenous structure but subjecting the product to the unit operation which in the dairy industry is called homogenization. This treatment means that the fat spheres are subjected to a strong mechanical treat¬ ment which reduces the size cf the fat spheres down a size smaller than 10^ t In the present invention, where the water is the con¬ tinuous phase in the fat product, the product may easily be flavoured by fermenting a part or the whole pro¬ tein concentrate. In this way the'product may be given yoghurt-, kefir- or butter taste as desired. According to the proposed method a fat product contain¬ ing different kinds of fat may be obtained as desired. The method according to tn€ invention may with advantage be used, when the fat raw material consists of milk fat, since the obtained fat product has a su¬ perior spreadability at refrigerator temperature. Otherwise it may be very difficult to spread milk fat ( butter ) at this temperature. The homogenization of the achieved mixture may with advantage take place in a two-step homogenization pro¬ cess. It is possible to obtain a stable fat product by making the mixture pass once through a ho ogenizer, but with homogenization in two steps a still better distribution of the size of the fat spheres is obtained. After homogenization the still warm product is packed directly in consumer packings. The manufacture of a fat product according to the in¬ vention is described further with reference to the atta¬ ched flow-chart, which shows manufacture of a fat product based completely on milk, Fig.l, In this two alternatives are shown - the manufacture of a fat product from skim milk and from cream. The skim milk, alternatively cream, is pasteurized for three minutes at 92°C, is cooled thereafter to 55°C anc ultra-filtrated at pH 6,0-7,0. At that the milk raw- material is concentrated in that water and lactose are passed through the membrane. As may be seen from the flow-chart the skim milk is concentrated (1 : 3,3) more than the cream ( 1 : 2,5). After cooling to 22°C the taste culture comprising e.g. butter acid bacteries is added to a part or the whole amount of the protein concentrate, after which it may ferment during 19 hours at 22°C. The skim milk concentrate has a protein content of 10-11% the cream concentrate a protein content of up to 8%. The protein concentrate is thereafter mixed with fat raw material in the form of butter or concentrated cream and salt, the mixture is heated to 65 C and homogenized in 2 two steps, step 1 with a pressure of 150 kp/c (15 MPa) 2 step 2 with a pressure of 50 kp/cm ( 5 MPa) . The pro¬ duct may be packed warm directly after the homogenization, after which it is cold stored. In order to give some more information about the inven¬ tion an example on the manufacture of a fat product ac¬ cording to the invention is given below. Example 143 kg cream (10% fat) is pasteurized at 92°C with a holding time of three minutes. After the pasteurization the cream is cooled to 55°C and ultra-filtrated, such that the concentration is increased 2,5 times, that means that the protein content is about 8%. After the concen¬ tration there remain 57 kg milk concentrate, which is cooled to 22°C. Two thirds of the concentrate is .fermen¬ ted during 18 h at 22°C to appr. pH 4,8. Fermented and triermented concentrate is mixed with 50 kg unit butter and 1,2 kg salt. A favourable pΞ for the achieved mix¬ ture is 5,0-5,2. After having heated the mixture to 65°C it is omogenized in two steps (150 resp.50 kp/σn 2 ), ______ after which the obtained fat product, is wrapped in consu¬ mer packings. The method of producing the f t product according to the invention is shown in fig.2 of the attached draw¬ ing, on which it is seen that skim milk is heated and pasteurized in one section 1 of a plate heat exchanger and cooled by flowing in counter-current to the milk to be treated in another section 2. After this treatment the milk is led to the UF-filter 3 and concentrated. The concentrate is forwarded to the plate heat exchanger 4 and cooled. A part of the concentrate is fermented by adding taste culture. After fermenting for the desired time in a tank 5 concentrated cream is added. The cream has been heated and concentrated in a cen¬ trifugal separator 6, after which it is led to the tank 5. The mixture is led to a plate heat exchan¬ ger 7 and heated to the desired homogenization tem¬ perature. It is then forwarded to a 2-step homoge- nizator 8, where the fat-in-water emulsion is formed. The fat product is packaged warm.

Claims: Claims 1. A fat product, which is spreadable at refrigerator temperature and contains 35-55% fat, 4-7% protein and 41-58% water, c h a r a c t e r i z e d i n that the protein has been obtained from an ultra-filtrated milk product, at which the fat product after mixing of protein and a fat raw material and homogenization of the fat drops consists of a stable oil-in-water erxilsicn, which emulsion is stabilized by the milk protein, and which fat product is free from additives in the form of stabi¬ lizing agents and emulsifiers. 2. A fat product according claim 1, c h a r a c t e ¬ r i z e d that the fat raw material consists of milk fat. 3. Method of manufacture of the spreadable fat pro¬ duct according to claim 1, c h a r a c t e r i z e d i n that a milk product with or without fat is pasteurized at 85-95°C, ultra-filtrated after cooling in order to achieve a concentration of protein and at the same time a diminishing of the lactose content, after which the concentrate enriched in proteins is mixed with the fat raw material and the fat spheres are finely divided by a strong mechanical treatment (homo¬ genization) at 40-70°C in order to form a stable oil- in-water emulsion. 4. Method according to claim 3, c h a r a c t e ¬ r i z e d i n that a part of the protein concentrate is flavoured by fermentation. 5. Method according to claim 3, c h a r a c t e ¬ r i z e d i n that .used f t raw material consists of milk fat. 6. Method according to claim 3, c h a r a c t e ¬ r i z e d i n that homogenization is carried through in form of a two-s ' tep homogenization. 7. Method according to claim 3, c h a r a c t e ¬ r i z e d i n that the formed fat product is packaged warm .

Inventors: ANDERSSON KENNETH LARS OLOF, ANDERSSON, KENNETH, LARS, OLOF
Applicants: ALFA LAVAL AB, ALFA-LAVAL AB
Application year: 1982
Main classification: A23D5
IPC codes: A23C9, A23C23, A23D7