Processing method of high-flavor and low-reducing buffalo milk based on centrifugal separation technology

Abstract

The application discloses a processing method of high-flavor and high-reduction buffalo milk based on centrifugal separation technology, and particularly relates to the field of dairy product processing technology.The steps are as follows: S1, buffalo milk is subjected to centrifugal separation to obtain thin water cream and skimmed milk liquid; S2, the separated thin water cream in step S1 is subjected to freezing solidification; S3, the separated skimmed milk liquid is subjected to spray drying to realize liquid phase to solid phase and form milk powder; and S4, when used, the milk powder and the solidified thin water cream are compounded according to the reconstitution proportion of fresh milk standard to prepare original-flavor fresh buffalo milk.The application solves the problems of processing difficulty, transportation and storage difficulty and excessive loss of fresh buffalo milk flavor in long-distance use of existing buffalo milk under high milk fat. Through the key technologies of the optimal defatting proportion and high-concentration thin cream, the preservation, displacement transportation and flavor reversion of the buffalo milk are ensured. The application provides a new technology for flavor reversion of high-fat-content buffalo milk in long-distance and long-term application.

Description

Technical Field

[0001] This invention relates to the field of dairy processing technology, and in particular to a processing method for buffalo milk with high flavor fidelity based on centrifugal separation technology. Background Technology

[0002] Water buffalo are dairy livestock native to tropical and subtropical regions. They are hardy, grazing-tolerant, disease-resistant, adaptable, and produce high-quality milk. Their ability to thrive in hot and humid environments is unmatched by other similar livestock, such as Holstein cattle. Water buffalo are an excellent dairy breed, and buffalo milk is the world's second-largest source of human milk and dairy products, after cow's milk. Water buffalo milk is highly nutritious, often referred to as "premium milk," with high levels of dry matter, milk fat, milk protein, minerals, vitamins, and especially unsaturated fatty acids and essential amino acids. my country is the third-largest producer of water buffalo, possessing enormous potential for water buffalo milk production. With a solid foundation in the water buffalo dairy industry, it is expected to develop into my country's second-largest pillar of the dairy industry. Improving the economic and social benefits of the water buffalo dairy industry will positively contribute to the development of the global dairy industry.

[0003] Due to the common problems of small-scale dairy farms, remote production environments, and inconvenient transportation, such as buffalo milk, the milking parlors and processing plants are often located in different places, increasing processing and transportation costs. Furthermore, buffalo milk requires refrigeration for a period of time before processing, and the long transportation time from the production site to the consumer makes it difficult to preserve the flavor of fresh buffalo milk. Summary of the Invention

[0004] The present invention aims to provide a processing method for buffalo milk with high flavor restoration based on centrifugal separation technology, which solves the problem of excessive flavor loss during long-term storage, transportation and subsequent reconstitution of high-fat buffalo milk.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: a processing method for buffalo milk with high flavor restoration based on centrifugal separation technology, comprising the following steps:

[0006] S1. The buffalo milk is centrifuged to obtain a light cream with a milk fat content of more than 60% and containing the main flavor substances of buffalo milk, and a skim milk liquid rich in milk protein.

[0007] S2. Freeze and solidify the watery butter separated in step S1.

[0008] S3. Spray drying is used to convert the skim milk separated in step S1 into a solid phase and form milk powder.

[0009] S4. When using, mix milk powder and solidified water-based butter according to the standard ratio for fresh milk to prepare buffalo milk with the original flavor.

[0010] Furthermore, the centrifugal separation process in step S1 employs a multi-disc high-speed separator.

[0011] Furthermore, the freezing temperature in step S2 is from -18°C to -22°C.

[0012] By employing the above-mentioned setup, freeze-curing can reduce the volume of liquid milk, better preserve the main flavor, and facilitate long-term, long-distance storage and transportation.

[0013] Furthermore, in step S3, hot air at 140-145℃ is used for drying.

[0014] Furthermore, in step S1, the buffalo milk is filtered through a ceramic membrane.

[0015] By using the above setup, the loss of active ingredients in milk during traditional processing is reduced by utilizing ceramic membranes, which greatly improves product quality and the content of active substances such as IgG.

[0016] Compared with existing technologies, the beneficial effects of this solution are:

[0017] 1. In addition to solving the problems of excessive flavor loss during long-term storage, displacement, and reconstitution of high-fat buffalo milk, this solution can also solve the problem of milk powder being prone to sticking and collapsing due to its high fat content after being spray-dried into milk powder.

[0018] 2. This solution reduces the difficulty of transportation by processing fresh buffalo milk into solid milk powder and solid cream that can be transported via cold chain, while maintaining the flavor of fresh buffalo milk. Attached Figure Description

[0019] Figure 1 These are the GC-IMS two-dimensional spectra of volatile organic compounds in the three samples in this embodiment;

[0020] Figure 2 These are the GC-IMS three-dimensional spectra of volatile organic compounds from the three samples in this embodiment;

[0021] Figure 3 These are the GC-IMS spectra of volatile organic compounds from the three samples in this embodiment (difference comparison);

[0022] Figure 4 This is a gallery plot (fingerprint) of the volatile organic compounds in the sample in this embodiment;

[0023] Figure 5 This is a similarity analysis diagram of the three samples in this embodiment;

[0024] Figure 6These are the PCA (principal component analysis) plots of the three samples in this embodiment. Detailed Implementation

[0025] The present invention will be further described in detail below through specific embodiments:

[0026] Example

[0027] A processing method for buffalo milk with high flavor reproducibility based on centrifugal separation technology, comprising the following steps:

[0028] S1. Buffalo milk (with a fat content as high as 7%-8%) is separated into milk fat using a high-resolution centrifuge. In this embodiment, a multi-disc high-speed centrifuge is used to separate the milk fat, yielding light cream with a milk fat content of over 60% and containing the main flavor substances of buffalo milk, and skim milk rich in milk protein. Before separation, the buffalo milk in this embodiment needs to be filtered through a ceramic membrane. The main purposes are: 1. Low-temperature membrane filtration can reduce protein denaturation and increase product solubility. 2. It effectively protects various active substances such as IgG in milk. 3. It separates and concentrates proteins according to their molecular weight. The entire process is performed using room-temperature physical filtration, reducing steam energy consumption and significantly lowering production costs. 4. It greatly reduces production energy consumption and lowers production costs.

[0029] S2. Freeze the separated water-based butter from step S1 at a temperature of -18°C to -22°C.

[0030] S3. The skim milk separated in step S1 is spray-dried to achieve liquid-to-solid phase conversion and form milk powder. In this embodiment, the spray-drying temperature is 140-145℃. Meanwhile, the skim milk obtained after defatting has a protein content of more than 24%. Therefore, lower temperatures are used for sterilization and concentration, a protein retention tube is set up, a triple-effect concentration system is used, and the spray tower is heightened by 20% to obtain a longer settling time for hot air countercurrent powder particles in the drying tower.

[0031] S4. When using, mix powdered milk fat and solidified high-concentration diluted buffalo milk oil in a certain proportion to prepare buffalo milk with the original flavor.

[0032] The principle and effects of this technical solution:

[0033] Whole buffalo milk powder, made by spray drying concentrated Holstein cow milk in the traditional method, has a fat content as high as 35%. This causes powder particles to stick to the nozzle during the spraying process, affecting the diameter of the milk powder particles and clogging the nozzle pores, thus reducing production efficiency. At the same time, the high fat content of the finished product leads to clumping and adhesion during storage, directly shortening the shelf life and affecting the solubility during reconstitution. The excessively high fat content in whole buffalo milk powder can easily produce an oily or rancid taste, and after reconstitution during production and use, there is a significant loss of the original flavor of fresh buffalo milk.

[0034] In this embodiment, high-fat buffalo milk is first separated into light cream and skimmed milk through fat separation. A multi-disc high-speed separator is used to separate the light cream with a fat content of 60%-70%, which is immediately frozen to -18°C for solidification, storage, and transportation, preserving the main flavor components of the buffalo milk. The remaining skimmed milk, after defatting, has a protein content of over 24%. By using lower temperatures in the sterilization and concentration processes, and to achieve a longer settling time for the hot air counter-current powder particles in the drying tower, the spray drying tower is increased by 20%, and the hot air temperature used in spray drying is reduced by 5-10°C (not exceeding 140-145°C), better energy-saving effects are achieved. This portion of high-protein skim milk is produced using spray drying to achieve liquid-to-solid dehydration for storage and transportation. This reduces the liquid volume and solves the problems of adhesion and collapse of high-fat buffalo milk powder. Upon arrival at its destination, it is reconstituted according to fresh milk standards, resulting in liquid buffalo milk with a high degree of sensory flavor reproduction. Flavor analysis confirms that its flavor is very close to that of fresh buffalo milk.

[0035] Flavor analysis:

[0036] Three samples were taken, and their details are as follows:

[0037] Sample 1: Fresh buffalo milk was collected and its sensory flavor and other characteristics were used as a benchmark (as a standard control group);

[0038] Sample 2: Fresh buffalo milk was separated into dilute cream fat using the technical solution of the example, and then quick-frozen and stored at -18°C. Meanwhile, the remaining skim milk was sterilized, concentrated, and spray-dried into skim buffalo milk powder. When used, the milk powder and frozen cream were combined to make reconstituted milk (test sample).

[0039] Sample 3: Whole milk powder made using traditional methods, reconstituted into reconstituted milk based on equal dry matter (blank control sample).

[0040] Detection method:

[0041] Analysis was performed using a gas phase ion mobility spectrometer (CC-INS), with three parallel experiments conducted for each sample. Based on two-dimensional and three-dimensional spectra, difference spectral analysis was performed, and principal component analysis and similarity analysis were conducted on the data to detect the main volatile substances.

[0042] Test results:

[0043] Two-dimensional map

[0044] Ion migration spectra of volatile substances from the three samples are shown below. Figure 1 As shown. The red vertical line at 1.0 on the horizontal axis represents the RIP peak. The vertical axis represents the retention time (s) in gas chromatography, and the horizontal axis represents the ion migration time. Each point on either side of the RIP peak represents a volatile organic compound. The color represents the concentration of the substance; white indicates a lower concentration, red indicates a higher concentration, and the darker the color, the greater the concentration.

[0045] 3D Atlas

[0046] To facilitate intuitive observation and comparison of the differences in volatile substances among the three samples, three-dimensional spectra were used to characterize the volatile organic compounds in the three samples. Figure 2 The three-dimensional spectra (retention time, migration time, and peak intensity) generated for the three samples clearly show the differences in volatile organic compounds among the three samples (sample 1, sample 2, and sample 3 from left to right). The different signal peak heights in region A indicate differences in the content of this substance among the three samples; the different signal peak densities in region B indicate significant differences in their volatile flavor compounds.

[0047] Difference map:

[0048] To more clearly contrast these differences, a difference comparison mode can be used. Figure 3 ): Select the spectrum of sample 1 as the reference, and subtract the reference from the spectra of other samples. If the volatile organic compounds of the two samples are the same, the background after subtraction will be white, while red indicates that the concentration of the substance is higher than the reference, and blue indicates that the concentration of the substance is lower than the reference.

[0049] Fingerprint pattern:

[0050] To further analyze the differences in volatile flavor compounds among the samples, fingerprint spectrum was generated for each peak in the GC-IMS two-dimensional chromatogram to identify characteristic peak regions in different sample groups. Rows and columns represent volatile substances and their corresponding amounts at different times (each row in the figure represents all selected signal peaks from a single sample), and each column represents the signal peaks of the same volatile organic compound in different samples. Figure 4 This allows us to see complete volatile organic compound (VOC) information for each sample and the differences in VOCs between samples. Figure 4The fingerprints are for three samples.

[0051] Main volatile substances:

[0052] According to the GC-IMS results, a total of 31 signal peaks were detected, and the volatile components of all of them were identified as shown in Table 1. 2-Butanone, phenethyl formate, pentanal, 2-hexenol, butanedione, butyraldehyde, ethyl acetate, and 2-heptanone were considered to constitute the common flavor characteristic peak regions of the three samples, but the content of each component was significantly different.

[0053] Table 1. Identification of the main volatile components in the three samples

[0054]

[0055]

[0056] Similarity analysis:

[0057] The similarity analysis of the three samples is as follows: Figure 5 The larger and darker the black dot, the higher the similarity between the two samples. To more intuitively represent the similarity between samples, the similarity is expressed in numerical form, as shown in Table 2.

[0058] Table 2. Similarity results of the three samples

[0059]

[0060] Principal component analysis:

[0061] The PCA results of the three milk samples are as follows: Figure 6 As shown in the figure, the contribution rates of PC1 and PC2 are 69% and 20%, respectively, and the cumulative variance contribution rate is 89%, indicating that the PCA results are valid. The figure also shows that the three replicates of each group of samples overlap well, indicating good experimental repeatability and credibility. Samples 2 and 3 are relatively close, indicating that their composition is similar, while sample 1 is relatively far from samples 2 and 3, indicating significant compositional differences.

[0062] Test results:

[0063] 1. According to the detection and analysis results, compared with sample 1, sample 2 is closer to sample 1, with a similarity score of 52.6, and sample 3 has a similarity score of 37 with sample 1.

[0064] 2. By Figure 4 As can be seen from the ICP-MS fingerprints of the three samples, the volatile composition of sample 2 is very similar to that of sample 1, but significantly different from that of sample 3.

[0065] The above are merely embodiments of the present invention, and common knowledge such as specific structures and / or characteristics in the solutions are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A processing method for buffalo milk with high flavor reproducibility based on centrifugal separation technology, wherein, The method includes the following steps: S1. The buffalo milk is centrifuged to obtain a light cream with a milk fat content of 60%-70% and containing the main flavor substances of buffalo milk, and a skim milk liquid rich in milk protein. S2. Freeze and solidify the watery butter obtained in step S1; S3. Spray drying is used to convert the skim milk obtained in step S1 from the liquid phase to the solid phase, forming milk powder; S4. When using, the milk powder obtained in step S3 and the solidified water-based butter obtained in step S2 are mixed according to the standard fresh milk restoration ratio to prepare buffalo milk with the original flavor. In step S1, the fat content of the buffalo milk is 7%-8%; the centrifugal separation is carried out using a multi-disc high-speed separator. The freezing temperature in step S2 is -18°C to -22°C; In step S3, hot air at 140-145℃ is used for spray drying, and the height of the powder spraying tower is increased by 20%.

2. The method according to claim 1, wherein, In step S1, the buffalo milk is filtered through a ceramic membrane.

Images