Method for reducing bacteria in dried fruits containing fats and oils and atomizing pulverizer

Abstract

The present invention circumvents the conventional drawbacks of the method for reducing bacteria in dried fruits containing fats and oils in a simple and cost-effective manner. 【Solution means】The present invention relates to a method for reducing bacteria in dried fruits containing fats and oils, particularly cocoa beans, wherein the dried fruits are subjected to at least heat treatment and water supply in a housing device (4). In the first step, the dried fruits are filled into the processing housing part (14) of the housing device (4), and the processing housing part (14) is heated. In the second step, at least one atomization step is initiated. In the third step, a predetermined maximum temperature TM ≤ 110 °C is reached. In the fourth step, moisture in the form of water and / or steam is supplied to the processing housing part (14). In the fifth step, the atomized product is at least dried. The present invention also relates to an atomizing and pulverizing device for carrying out this method.

Description

Technical Field

[0001] The present invention relates to a method for reducing bacteria in dried fruits containing fats and oils, particularly cocoa beans, wherein the dried fruits are subjected to at least heat treatment and water supply in a housing device. Further, the present invention relates to an atomizing and pulverizing device for carrying out such a method.

Background Art

[0002] Dried fruits containing fats and oils, such as cocoa beans, require pretreatment and are fermented and stored. In this process, the dried fruits can be contaminated with pathogenic bacteria, and in particular, Salmonella is regarded as the most dangerous contaminant when consumed later. For example, in products such as roasted cocoa beans, the roasting process reduces bacteria during further processing of the dried fruits due to the effect of heat, but it should be noted that an overly strong heat treatment leads to an undesirable flavor for the dried fruits. Further, processes using ionizing radiation or gamma rays have also been developed to reduce bacteria. However, these procedures require additional processing steps and are thus costly and time-consuming.

[0003] Another method for reducing bacteria is known from German Patent Application Publication No. 34 17 125, in which water is added to the dried fruits, the temperature and pressure are rapidly increased and then rapidly decreased, and subsequently homogenized under vacuum to convert the dried fruits into a pourable and / or fluid mass. However, this process requires additional labor or fundamentally new equipment to achieve the maximum values of pressure and temperature and to provide a vacuum. Also, the application of high-temperature heat always involves the risk of flavor changes.

Summary of the Invention

Problems to be Solved by the Invention

[0004] Therefore, an object of the present invention is to avoid the aforementioned drawbacks in a simple and cost-effective manner.

Means for Solving the Problems

[0005] This object is achieved by the following method of the present invention. In the first step, the dried fruits are filled into the processing housing part, and the processing housing part of the housing device is heated. In the second step, at least one atomization step is started. In the third step, a predetermined maximum temperature TM ≤ 110 °C is reached. In the fourth step, moisture in the form of water and / or steam is introduced into the processing housing part. In the fifth step, the atomized product is at least dried. In the context of cocoa beans and chocolate made from cocoa beans, "atomization" is understood to mean "coating". Thereby, the chocolate is continuously stirred and kneaded, and volatile substances are removed. The maximum temperature TM refers to the internal temperature of the processing housing part.

[0006] A particularly gentle and effective method for reducing bacteria is achieved by preheating the processing housing part to about TM = 90 °C.

[0007] When 2 g / 100 g (water / dried fruit), up to a maximum of 5 g / 100 g of moisture is added at the start of the atomization step and further moisture is added at predetermined time intervals, a very suitable moist atmosphere for bacteria reduction is provided. The addition of moisture can be monitored, for example, by weight measurement or volume measurement, and the moist atmosphere can also be monitored.

[0008] If an air mass exchange, also referred to as open process control, is possible during the atomization step, caking can be continuously avoided even at high humidity. This air mass exchange can be reliably carried out in a controlled manner in order to make it easier to monitor the humidity of the processing housing part. This can be carried out, for example, by opening and closing the processing housing part or by suction.

[0009] If an additional grinding step is started in the second step in parallel with the final step, the processing procedure can be made more efficient and the reduction of bacteria can be further improved. In particular, the grinding step is carried out at the maximum grinding pressure possible, whereby a high bacteria reduction effect can be obtained with a final product that is as fluid as possible.

[0010] This object is also achieved by an atomizing and grinding device for carrying out such a method. In this atomizing and grinding device, a housing device equipped with a drive device and a control device for a drive shaft is provided. The housing device has a processing drum provided with a plurality of kneading wheels rotatable around the drive shaft. Further, the kneading wheels are connected to the drive shaft, a grinding device is provided between the kneading wheels and the processing drum, a heating device is provided in the processing drum, a connecting device for supplying moisture is provided, and the control device is configured to control at least the maximum temperature TM and the supply of moisture for the purpose of reducing bacteria. By appropriately controlling the atomizing and grinding arrangement configured in this way, it is possible to very easily and efficiently reduce bacteria during the atomizing and grinding process.

[0011] At this time, it is preferable that the grinding device is adjustable. Here, the grinding device can be composed of a grinding arm directed towards the kneading wheel of the processing drum and a grinding rod provided inside the processing drum, and the inclination angle of the grinding arm is adjustable.

[0012] The measurement sensor for measuring moisture is preferably provided in the processing housing part.

[0013] The present invention will be described in more detail with reference to the drawings shown below.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0015] Figure 1 shows a perspective sectional view of the atomizing and pulverizing apparatus 2 according to the present invention. This example relates to the production of chocolate products and is also referred to as the coating process. The atomizing and pulverizing apparatus 2 has a housing device 4 provided with a drive device 6 schematically shown for the drive shaft 8. Further, a control device 10 is schematically shown, which controls specific process parameters that affect the reduction of bacteria in the coating product, which is chocolate in this case, as will be described later.

[0016] In the illustrated atomizing and pulverizing apparatus 2, cocoa beans are introduced through a funnel 12 into a processing housing portion designed as a processing drum 14, where the coating process and the pulverizing process are carried out. For this purpose, the processing drum 14 is provided with several kneading wheels 16 (only one of which is shown here). These kneading wheels 16 are connected to the drive shaft 8 by kneading arms 18. The kneading wheels 16 and the corresponding kneading arms perform the coating process. A pulverizing device 22 is provided between the kneading wheels 16 and the inner side 20 of the processing drum 14.

[0017] The pulverizing device 22 basically consists of a pulverizing arm 24 directed towards the kneading wheels 16 of the processing drum 14 and a pulverizing rod 26 provided on the inner side 20 of the processing drum 14.

[0018] The pulverizing arm 24 is provided with a support plate 28 at its free end, and the pulverizing pressure can be set by the inclination angle of the pulverizing arm 24 via a pulverizing pressure adjusting device 30.

[0019] To heat the processing drum, a heating device 32 is provided which is fluidly connected to a hot water jacket 34 of the processing drum 14. Moisture can be supplied to the processing drum 14 via a connecting device 36. For a further basic structure of such an atomizing and pulverizing apparatus, reference may be made to British Patent Application Publication No. 2317840.

[0020] In the above-described atomization pulverization device 2, a preferred method for reducing bacteria in cacao beans is described below to perform the reduction of bacteria in cacao beans as gently as possible in the coating pulverization process. In the first step, the processing drum 14 of the housing device 4 is preheated to a temperature TM = 90°C. After reaching this temperature, in the second step, the cacao beans are introduced into the processing drum 14 through the funnel 12. Next, in the third step, the coating process and the pulverization process are started, and in the fourth step, at the start of the process, 2 g / 100 g (water / dried fruit) of moisture is added in the form of water through the connecting device 36. Thereafter, more moisture is added at predetermined time intervals. The control of the humidity and temperature inside the processing drum 14 is performed by the control device 10. All of this is done in an open process where air mass exchange is possible during the coating process and the pulverization process. The pulverization process is performed at the highest possible pressure here to ensure the fluidity of the coating product, which is chocolate in this case, and to avoid sticking and aggregation of the chocolate.

[0021] Figure 2 is a diagram showing the influence of the shell temperature on bacteria reduction when moisture is added in the form of 2 g / 100 g of water during the operation of the open system. The processing drum was preheated to TM = 60°C in the first experiment 38, to TM = 80°C in the second experiment 40, and to TM = 90°C in the third experiment 42, respectively. The product temperature is basically lower than the temperature of the processing drum 14 and is shown in °C on the right Y-axis. The effect on bacteria reduction can be confirmed from the broken lines 44, 46, and 48. The broken line 44 corresponds to a processing temperature of 60°C, the broken line 46 corresponds to a processing temperature of 80°C, and the broken line 48 corresponds to a processing temperature of 80°C, respectively. The maximum bacteria reduction amount is achieved at the temperature TM of the processing drum 14 of 90°C and can be read on the left Y-axis (GKZ) in logarithmic form.

Claims

1. A method for reducing bacteria in dried fruits containing fats and oils, particularly cocoa beans, comprising: the dried fruits are subjected to at least heat treatment and water supply in a housing device (4); a first step of filling the dried fruits into a processing housing part (14) of the housing device (4) and heating the processing housing part (14); a second step of starting at least one atomization process; a third step of reaching a predetermined maximum temperature TM ≤ 110 °C; a fourth step of introducing moisture in the form of water and / or steam into the processing housing part (14); and a fifth step of at least drying the atomized product.

2. The method for reducing bacteria according to claim 1, wherein the housing device is preheated to about TM = 90 °C.

3. The method for reducing bacteria according to claim 1, wherein at least at the start of the atomization process, moisture is added in the form of water in an amount of 2 g / 100 g (water / dried fruit), up to a maximum of 5 g / 100 g, and further moisture is added at predetermined time intervals.

4. The method for reducing bacteria according to claim 1, wherein during the atomization process, an exchange of air mass, also referred to as open process control, is possible.

5. The method for reducing bacteria according to any one of claims 1 to 4, wherein in the second step, an additional grinding process is started in parallel with the atomization process.

6. The method for reducing bacteria according to claim 5, wherein the grinding process is carried out at the maximum possible grinding pressure.

7. An atomizing and grinding device for implementing the method for reducing bacteria according to claim 5, comprising: a housing device (4) provided with a drive device (6) and a control device (10) for a drive shaft (8), the housing device (4) having a processing drum (14) as a processing housing part, a plurality of kneading wheels (16) rotatable via the drive shaft being provided in the processing drum (14), the kneading wheels (16) being connected to the drive shaft (8) via kneading arms (18), a grinding device (22) being provided between the kneading wheels and the processing drum (14), a heating device (32) for the processing drum (14) being provided, and a connecting device (36) for supplying moisture being provided, the control device (10) being installed for adjusting at least the maximum temperature TM and the moisture supply for the purpose of reducing bacteria.

8. The atomizing and pulverizing device according to claim 7, wherein the pulverizing device (22) is adjustable.

9. The atomizing and pulverizing device according to claim 8, wherein the pulverizing device (22) includes a pulverizing arm (24) directed toward the kneading wheel of the processing drum (14) and a pulverizing rod (26) provided inside (20) of the processing drum (14), and the pulverizing arm (24) is adjustable with respect to its inclination angle.

10. The atomizing and pulverizing device according to claim 7, wherein a measurement sensor for measuring moisture is provided in the processing housing portion (14).

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