A kind of method that adopts gas lift type common loop reactor to prepare fat to control oxidation product
Technical field
The present invention relates to a kind of method that adopts gas lift type common loop reactor to prepare fat to control oxidation product, prepared fat to control oxidation product can be used as precursor of meat-flavour essence, and further reaction for preparation goes out meat flavour.
Background technology
Carbonyl containing compounds such as the small molecules aldehyde in the fats oxidn product, ketone are the important precursor of reaction for preparation meat flavour, these small molecules aldehyde, ketone and contain the product that aminocompound carries out Maillard reaction with amino acid, peptide, polypeptide, protein etc. and have stronger volatility are the important component that constitutes the feature fragrance of Different Kinds of Meat.Take the method for controlled oxidation, promptly control the degree of fats oxidn, can make fully oxidation of fat under the situation of becoming sour not producing, content height, the kind of important aldehyde, ketone carbonyl precursor are many in the oxidation products that obtains.Not only quality is more stable with meat flavour that the further reaction for preparation of this fatty controlled oxidation precursor goes out, and it is strong to have the true property of picture, the advantage that the characteristic fragrance of meat aromatic flavour, harmony and various meat is outstanding, it can be used on as natural level foodstuff additive in multiple food flavouring such as chickens' extract, condiment for instant noodles, sausage, can, quick-freezing boiled dumplings or the food.
Existing method adopts under the heating condition, the airway ventilation prepares precursor of meat-flavour essence (Sun Baoguo in conjunction with mechanical stirring, Xie Jianchun, Liang Menglan, Peng Qiuju, Wen Zhiyong. a kind of fatty controlled oxidation prepares the method .ZL 200410030864.4 of precursor of meat-flavour essence), exist that energy consumption height, reaction vessel are unsuitable for cleaning, loaded down with trivial details defective is amplified in industry.
Summary of the invention
The purpose of this invention is to provide a kind of method that adopts gas lift type common loop reactor to prepare fat to control oxidation product.This method has overcome the shortcoming and defect of existing method.Used gas lift type common loop reactor, in bubbling reactor, added the inner member guide shell, when blasting gas in the guide shell, there is density difference in the inside and outside gas-liquid mixed phase of guide shell, form circulation around guide shell, gas-liquid two-phase is mixed well, thereby increase gas-liquid mass transfer performance and gas-liquid contact area by a larger margin, cut down the consumption of energy.Adopt gas lift type common loop reactor to prepare fat to control oxidation product, have the advantage that energy consumption is low, easy to clean and realization industry is amplified.
Technological process of the present invention is as follows: the fat of the weighing certain mass reactor of packing into, open reactor heating system and water of condensation, and after melting, fat adds the certain mass antioxidant again; Bubbling air produces circulation, utilize circulation with fat and antioxidant uniform mixing, reach preset heating temperature after, control certain air velocity and carry out the oxidizing reaction certain hour, obtain the fats oxidn product, collect and its peroxide value of sampling and measuring, anisidine value, acid number and total carbonyl content.
Gas lift type common loop reactor of the present invention is made of reactor tower body, guide shell, gas distributor, and the structure of guide shell comprises various forms such as single-stage, multistage, convergent-divergent; Reactor tower body height overall is 5~15 with the ratio of its internal diameter, and the internal diameter of guide shell and the internal diameter of body of the tower ratio are 0.4~0.9.Gaseous phase outlet at the cat head of loop reactor is equipped with condenser, goes into reactor in order to the volatile products condensing reflux that fats oxidn is produced, and the cooling medium of employing is a water.
The present invention adopts air as oxygenant.Source of the gas is provided by air compressor, and gas inlet pressure is 0.05MPa~0.2MPa; Air after the gas meter metering, is preheated to 100 ℃ earlier through purification, desiccant dehumidification in air preheater, enter loop reactor from the gas distributor that is arranged in the loop reactor bottom then.The flow velocity of gas is in the reaction process: 0.1~2m
3/ kg.h fat, the empty tower gas velocity of the interior gas of reactor is in 0.5cm/s~9cm/s scope simultaneously.
The Heating temperature of fats oxidn is 80~180 ℃ among the present invention, and oxidization time will be generally 1~10h according to condition changings such as air velocity and Heating temperatures.In the heated oxide process, should adjust the condensate flow of overhead condenser according to air velocity and Heating temperature, be back in the reactor to guarantee that volatile component that fats oxidn produces all is condensed.
Fat of the present invention is a kind of or various greasy combinations of animal tallow, vegetables oil, fatty acid glyceryl ester, natural unsaturated fatty acids; Described antioxidant is vitamins C or vitamin-E or both combinations, and the antioxidant add-on is 0.01~0.5wt% of fat quantity.
The peroxide value of the fats oxidn product of the present invention's preparation is 5~1000eq/kg, and anisidine value is 1.0~252, and acid number is 0.5~10g KOH/kg fat, and total carbonyl content is 0.1%~5%.
The gas lift type common loop reactor that the present invention adopts, it is low, easy to clean to have energy consumption, realizes the advantage that industry is amplified easily.
The fats oxidn product of the present invention preparation can be used as and produces meat flavour thermal response raw material and use, and uses after also can taking modes such as steam distillation, underpressure distillation with important as precursors product separation and purifications such as aldehyde ketones.The meat flavour that the fats oxidn product of producing with method provided by the invention is made, it is long to have a shelf-life, and typical flavor is full, and advantage such as give off a strong fragrance.
Embodiment
Embodiment 1
10L gas lift type common loop reactor, height for reactor are 0.88m, and internal diameter is 0.103m; Guide shell is a single-stage cylinder shape guide shell, and diameter is 0.076m, highly is 0.55m.Reaction raw materials is tallow 2kg, and antioxidant is a vitamin-E, and add-on is the 0.05wt% of tallow.Heating temperature is 180 ℃, air velocity 1.1m
3Empty tower gas velocity 3.7cm/s in the/h, reactor, oxidization time 3h.The peroxide value of gained tallow oxidation products is 405eq/kg, and anisidine value is 120, and acid number is a 2.1gKOH/kg fat, and total carbonyl content is 1.2%.
Embodiment 2
Structure of reactor is with embodiment 1.Reaction raw materials is lard 2kg, and antioxidant is a vitamins C, and add-on is the 0.3wt% of lard.Heating temperature is 160 ℃, and air velocity is 2.5m
3Empty tower gas velocity 8.5cm/s in the/h, reactor, oxidization time 6h.The peroxide value of gained lard oxidation products is 782eq/kg, and anisidine value is 191, and acid number is a 1.8g KOH/kg fat, and total carbonyl content is 2.4%.
Embodiment 3
Structure of reactor is with embodiment 1.Reaction raw materials is peanut oil 2kg, and antioxidant is a vitamin-E, and add-on is the 0.1wt% of peanut oil.Heating temperature is 130 ℃, and air velocity is 2.2m
3Empty tower gas velocity 7.5cm/s in the/h, reactor, oxidization time 1h.The peroxide value of gained peanut oil oxidation products is 391eq/kg, and anisidine value is 96, and acid number is a 0.6g KOH/kg fat, and total carbonyl content is 0.7%.
Embodiment 4
20L gas lift type common loop reactor, height for reactor are 1.2m, and internal diameter is 0.153m; Guide shell is a secondary cylinder shape guide shell, and diameter is 0.114m, and total height is 0.85m, and first step height is 0.45m.Reaction raw materials is chicken fat 5kg, and antioxidant is a vitamins C, and add-on is the 0.1wt% of chicken fat.Heating temperature is 180 ℃, and air velocity is 5m
3Empty tower gas velocity 7.5cm/s in the/h, reactor, oxidization time is 3h.The peroxide value of gained chicken lipid oxidation product is 383eq/kg, and anisidine value is 191, and acid number is a 1.8g KOH/kg fat, and total carbonyl content is 2.4%.