Animals cured food is traditional food with local flavor, but the processing means and the more primitive and backward production technology, basic as hand-cured, natural air-dried small scale production, cycle length, quality by nature condition can not meet the food needs of industrial production. Application of refrigeration dehumidification principle, combined with their experience in small batches dried poultry conducted a number of air-dried equipment design, construction, system testing and product trial production, and engineering projects through the detection, identification, social and economic benefits generated .
Overview Food There are many methods of drying process, most rely on ventilation, heating, refrigeration and other means of vacuum. Natural ventilation and sun can dry the food end, but constrained by natural conditions, and food hygiene is difficult to guarantee. Mechanical ventilation, heating and drying conditions can produce improved but animal-based food processing, oil prone to oxidation, the surface yellow, and with spicy, decrease product quality. Vacuum freeze-drying are used for plant food processing. Cold winter drying is simulated natural environment, low temperature and humidity, higher wind speed, fast drying dehydration, while the formation of a special flavor of processing methods.
1, dry principle: the basic processing of food animals cured process is: after the slaughter of living by cleaning, salting, drying, (cooking), vacuum Package . In this process, it is necessary to ensure that food is not bad, but also to form a special flavor, while the production cycle can not be too long. Deterioration is mainly due to food microbial, enzymes and non-enzymatic effect. Affect microbial growth and reproduction of the conditions are moisture, temperature, nutrients and PH value etc.. Large water content, temperature and humid environment is conducive to the propagation of microorganisms. Enzymes can promote the maturation of meat after slaughter, the meat of lactate increase in acidity, inhibit bacterial growth, but at a high temperature preservation of proteins in the decomposition of ammonia under the action of protease, alkaline reaction to the meat, causing meat deterioration of corruption. Deterioration caused by non-enzymatic effect, such as fat rancidity, oil directly in high temperature air oxidation occurred. In the low temperature and humidity environment, the more the process of food deterioration can be delayed and weakened. Curing process, food soaked in very strong brine (salt solution), not only for meat with flavor, while protoplast plasmolysis occurred inhibit reproduction of microorganisms. Air-dried to remove the food part of the process of not only water, but also to precipitation of subcutaneous fat, and under the action of the enzyme so that the meat mature, gradually formed a special flavor. In order to shorten the production cycle, and to achieve continuous production throughout the year, we must create a low temperature, low humidity, high wind speed conditions of production, that is, artificial winter outdoor natural environment.
Drying process is divided into the following two basic stages:
1. Rapid dehydration: the initial period in the dry food with water more skin must be dry in a short time, and you should use high temperature and low air into that kind of food does not degenerate in ensuring the premise to maximize the supply air temperature to reduce its relative humidity, the greater the difference between the relative humidity inside and outside of food, water evaporates faster; the same time, the surface of fast food meat bear a layer of hard film to block the invasion of microbes, and breeding. At this stage, the surface water evaporation reduces the return air temperature, increase the return air relative humidity. This process accounts for about 30% of the total dry time.
2. Retarder mature: continuation of the dry, deep water to precipitate and subcutaneous fat, and make the meat to mature can be used at this time temperature, relative humidity of air into the low, low temperature and low humidity that ensure an enabling environment , then dried rely mainly on passing pressurized air fast food surface and the resulting pressure differential within the organization, so that deep water and subcutaneous fat foods slow seepage, the process about 70% of the total drying time.
Dried food required temperature, humidity, wind speed, air pressure and type of food, preserved methods, packaging methods, both relations of production and storage cycle. In general, food water content is low, use of dry-cured, cooked, vacuum packaging and other conditions may be appropriate to reduce the temperature and humidity requirements, but must be carried out sample tests, to obtain sufficient empirical data, can be recognized as a design target.
2, device configuration: dried food requirements for the realization of the special circumstances, should be selected industrial thermostat dehumidification unit, and configure a special ventilation system. Dried animal food under temperature, humidity, and the special requirements of food hygiene, appropriate under refrigeration dehumidification, heating thermostat principle of selection of equipment should have automatic operation, sub-regulation function, taking into account the air flow distribution in different seasons than to maximize the rate of addition of water, reduce energy consumption.
III Projects: proposed an air-dried in a food factory shop, schemes with geese 7000, three days, all air-dry; hung ago through the wet salt. BOLA TANGKAS