PROCESS FOR THE PREPARATION OF A POWDERY COMPOSITION COMPRISING BIOACTIVE MOLECULES

Abstract

Process for the preparation of a powder comprising bio active molecules, said process comprising the steps of (i) providing a liquid composition comprising bio active molecules, (ii) optionally pre-heating said liquid composition, provided that the temperature of the liquid composition does not exceed 65° C., (iii) transporting the optionally pre-heated liquid composition to the top of a spray drying tower via a tower feeding line, (iv) raising the temperature of the optionally pre-heated liquid composition using a direct electric volumetric heater located within the tower feeding line, the final temperature of the liquid composition being in the range 60-90° C., followed by (v) transporting the resulting liquid composition via the tower feeding line to the atomizer of a spray-dryer.

Claims

1. Process for the preparation of a powder comprising bioactive molecules, said process comprising the steps of: a. providing a liquid composition comprising bioactive molecules, b. optionally pre-heating said liquid composition, provided that the temperature of the liquid composition does not exceed 65° C., c. transporting the optionally pre-heated liquid composition to the top of a spray drying tower via a tower feeding line, d. raising the temperature of the optionally pre-heated liquid composition using a direct electric volumetric heater located within the tower feeding line, the final temperature of the liquid composition being in the range 60-90° C., followed by e. transporting the resulting liquid composition via the tower feeding line to the atomizer of a spray-dryer.

2. Process according to claim 1 wherein the bioactive molecules are bioactive molecules naturally occurring in milk.

3. Process according to claim 1 wherein the direct electric volumetric heater operates by dielectric heating, ohmic heating, or pulsed electric field.

4. Process according to claim 3 wherein the direct electric volumetric heater is a pulsed electric field (PEF) apparatus.

5. Process according to claim 1 wherein the residence time in the part of the tower feeding line between the direct electric volumetric heater and the atomizer is less than 20 seconds.

6. Process according to claim 1 wherein the bioactive molecules are proteins naturally occurring in milk.

7. Process according to claim 6 wherein said proteins are selected from the group consisting of antimicrobial factors, immunoglobulin factors, cytokines, pro-/anti-inflammatory factors, chemokines, digestive enzymes, protein hormones, transporters, glycomacropeptides, α-lactalbumin, β-lactoglobulin, bovine serum albumin, and proteins of the milk fat globule membrane.

8. Process according to claim 7 wherein said proteins are immunoglobulins.

9. Process according to claim 2 wherein the liquid composition comprising bioactive molecules naturally occurring in milk comprises whole milk, semi-skimmed milk, skimmed milk, colostrum, reduced fat milk, low fat milk, fat-free milk, casein, sweet whey, and/or acid whey.

10. Process according to claim 2 wherein the powder comprising bioactive molecules naturally occurring in milk is a dairy product.

11. Process according to claim 1 wherein the residence time in the part of the tower feeding line between the direct electric volumetric heater and the atomizer is less than 15 seconds.

12. Process according to claim 1 wherein the residence time in the part of the tower feeding line between the direct electric volumetric heater and the atomizer is less than 10 seconds.

13. Process according to claim 1 wherein the residence time in the part of the tower feeding line between the direct electric volumetric heater and the atomizer is less than 5 seconds.

14. Process according to claim 1 wherein the residence time in the part of the tower feeding line between the direct electric volumetric heater and the atomizer is less than 2 seconds.

15. Process according to claim 1 wherein the residence time in the part of the tower feeding line between the direct electric volumetric heater and the atomizer is less than 1 second.

16. Process according to claim 7 wherein said proteins are immunoglobulins selected from the group consisting of IgA, IgE, IgG, IgM, and IgD

17. Process according to claim 7 wherein said proteins are immunoglobulins selected from the group consisting of IgA and IgG.

18. Process according to claim 2 wherein the liquid composition comprising bioactive molecules naturally occurring in milk consists of whole milk, semi-skimmed milk, skimmed milk, colostrum, reduced fat milk, low fat milk, fat-free milk, casein, sweet whey, and/or acid whey.

19. Process according to claim 10 wherein the dairy product is selected from the group consisting of milk powder, casein powder, whey protein concentrate powder, whey protein isolate powder, serum protein concentrate powder, serum protein isolate powder, lactoferrin powder, powdered nutritional compositions for infants and/or young children, and base powders for powdered nutritional compositions for infants and/or young children.

20. Process according to claim 19 wherein the milk powder comprises whole milk powder, semi-skimmed milk powder, skimmed milk powder, colostrum powder, reduced fat milk powder, low fat milk powder, and fat-free milk powder.

Description

EXAMPLE

[0037] Raw milk was heated in 5 L stainless steel buckets in a water bath while agitating. The milk was heated to 45° C. prior to homogenization. Homogenization was carried out at 170 bar (first stage) and 30 bars (second stage).

[0038] This raw milk was subjected to three different processes: [0039] 1. A process mimicking legal pasteurization (74° C. for 20 seconds) before spray-drying, which involved heating the milk at 74° C. for 20 seconds in a tubular heater, followed by transportation to a tubular cooler. Transportation took 31 seconds, a time representative for transportation from a pasteurizer to a spray-drying nozzle. [0040] 2. A process mimicking minimized legal pasteurization and spray-drying, which process involved heating the milk in a tubular heater to a temperature of 50° C., followed by transportation to a tubular cooler. Transportation took 31 seconds, but at residence time of 20 seconds before cooler, the temperature was boosted to 74° C. using a PEF electric heating device. [0041] 3. A process mimicking pasteurization and direct atomization, which process involved heating the milk to a temperature of 50° C. in a tubular heater, transporting it to a tubular cooler in 31 seconds, and boosting the temperature just before the cooler to 74° C. using a PEF electric heating device. In this process, there was no residence time prior to cooling.

[0042] The tubular heater was a double jacketed tube wound in a coil. The double jacket was flushed counter-currently with hot water to reach the desired temperature. The PEF heating device contained ohmic heating cells with a 3 chamber design, 2× [1.8×10 mm] and 1× [1.8×20 mm], The field strength for electric heating was set at 300 V/cm. The pulse duration was gradually ramped up to 1000 μs; as soon as the pulse duration was reached the frequency was increased from 0 to 125 Hz in steps of ˜20 Hz. From 100 Hz onwards small steps of ˜5 Hz were used to prevent a temperature overshoot.

[0043] The tubular cooler was a wound double jacketed tube with ice water fed co-currently in the outer tube.

[0044] The processes were run for 15 minutes, after which samples were collected. Fluid exiting the cooler was collected in sterile containers and stored on ice.

[0045] Native immunoglobulin levels (Active IgG, active IGA, and active IgM) and lactoferrin were determined by the bovine IgG, IgA, IgM and LF ELISA quantitation set as described by R. L. Valk-Weeber, T. Eshuis-de Ruiter, L. Dijkhuizen, and S. S. van Leeuwen, International Dairy Journal, Volume 110, November 2020, 104814).

TABLE-US-00001 lactoferrin IgG IgA IgM Sample μg/ml % μg/ml % μg/ml % μg/ml % Raw milk 75.6 100 299.3 100 32.7 100 67.6 100 Process 1 38.2 50.4 166.9 21.3 8.0 24.2 14.5 21.3 Process 2 52.9 70.0 225.7 75.4 17.5 53.5 39.6 58.6 Process 3 66.5 88.0 259.6 86.7 28.4 86.5 62.8 92.8

[0046] This Table shows that the level of native immunoglobulins increases with decreasing heat load.

[0047] The effect of the spray-drying on the native Ig and lactoferrin levels was studied separately by feeding milk (inlet temperature: 50° C.) to a pilot spray-dryer at a pressure of 50 bar, an air inlet temperature of 170° C., and an air outlet temperature of 80° C. No loss in active IgG, IgM, and lactoferrin was detected; and only a minor loss (about 5%) in active IgA was observed.

[0048] In other words, bioactivity loss during pasteurization and spray-drying is caused by the heat load prior to spray-drying. Reducing this heat load by conducting the process in accordance with the present invention maintains large amounts of bioactives.