Improving the quality of milk dispersion in a counter-jet homogenizer

Abstract

Homogenization is a necessary process in the production of drinking milk and most dairy products. The specific energy consumption of the most common valve homogenizers reaches 8 kW h.t-1. A promising way to reduce it is the introduction of more effective counter-jet homogenizers. The purpose of these studies is to increase the efficiency of machines of this type through fuller use of their kinetic energy. To achieve this, the design of a ring reflector was developed and experimental studies were carried out to determine its influence on the efficiency of milk fat dispersion in a counter-jet homogenizer. Calculations were made to determine the reflector’s design parameters. An installation for experimental research has been developed, in which the required milk pressure is created with the help of compressed carbon dioxide. The dispersive indices of the milk emulsion were determined by computer analysis of milk sample micrographs obtained with an optical microscope and a digital camera using Microsoft Office Excel and Microsoft Visual Studio C# software using the OpenCV Sharp library. As a result of research, the formula for defining the angle of the reflector top has been determined analytically. Experimental studies proved its validity and allowed determination of the optimal diameter. A comparison of the dependence of the degree of homogenization on the excess pressure in a counter-jet homogenizer proves a 15 – 20% increase in the degree of dispersion when using a reflector. At the same time, specific energy consumption does not increase. Comparison of the distribution curves of milk fat globules by size after counter-jet homogenization and homogenization with a reflector suggests that the average diameter of fat globules for the experimental method decreases from 0.99 to 0.83 μm. This indicates the high quality of the dispersal characteristics of the milk emulsion after processing in a counter-jet homogenizer with a reflector.

The study of the cytotoxic effect of disinfectants

“…The IC50 of disinfectants based on the effect on the cell line of kidney origin (HEK 293) is Biodez -173.65 ±19.56 μl/l, Blanidas -514.20 ±16.54 μl/l, Virkon-S -402.48 ±24.87 μl/l, Neochlor -353.94 ±26.45 μl/l, Phan -44.13 ±5.7 μl/l, Chlorination -396.76 ±23.66 μl/l (Figure 4). The authors of the scientific works [44], [45], [46], [47], conducted a similar series of experimental studies, but the effect on the cell line of kidney origin (NEC 293) was: origin (HEK 293) is: Biodez -153.65 ±19.56 μl/l, Blanidas -414.20 ±16.54 μl/l, Virkon-S -302.48 ±21.57 μl/l, Neochlor -323.91 ±22.05 μl/l, Phan -34.11 ±3.7 μl/l, Chlorination -396.21 ±20.06 μl/l, in our opinion, such a difference may be related to non-compliance with both the temperature regime during experiments and the non-compliance with time regimes.…”

Determining the quality of milk fat dispersion in a jet-slot milk homogenizer

“…The urgency of development of jet dispersion of emulsions is evidenced by a large number of fundamentally different designs of jet milk homogenizers which were developed recently. They include counterflow-jet, impact-jet, cavitational hydrodynamic, jet homogenizers with the separate feed of the fat phase, mini-mixers, and microfluidizers [3][4][5][6][7][8][9][10][11][12][13][14][15]. The latter belong to the most advanced type of homogenizers that enable obtaining of a milk emulsion with the finest dispersed composition (with ADFG of 0.1 μm and less) [3].…”

“…This problem can be solved by using a counterflow-jet homogenizer. Its design is described in [9]. This homogenizer contains two opposite nozzles so that the fat phase is dispersed by the collision of the milk jets.…”

“…The counterflow-jet homogenizer features the creation of a high velocity of the runaround of fat globules by the dispersing medium and, as a result, high values of Weber's hydrodynamic criterion. It was shown in [9] that the counterflow-jet milk homogenizer provides ADFG at a level of 0.75-0.85 μm and has a specific power input of 1.2-1.5 kWh/t. However, the foaming-related issues, which occur because of the destabilization of protein particles when the milk emulsion comes into contact with air, remain unresolved.…”

Development of sour cream with vegetable oils using a food emulsion stabilised by an emulsifying complex

“…In such cases, the obtained fat products may have unsatisfactory quality during storage because fat globules without stabilisation by emulsifiers may be unevenly distributed in normalised mixtures and have an average size of more than 2 μm. The fat phase dispersion with obtaining fat globules with an average size of not more than 2 μm increases the nutritional value, improves organoleptic and improves the finished product's physical and chemical quality indicators [8]. Therefore, using vegetable or blended oils precisely in dispersed form is relevant to obtain new types of sour creamy consistency products.…”