A method for simultaneously extracting oil from sauce and determining fat content, peroxide value and acid value

Abstract

The present application belongs to the field of food technology, and discloses a method for simultaneously extracting oil and fat in sauce and determining the fat content, peroxide value and acid value. The present application is simple to operate and simple in instrument; the test time period is short, and the efficiency is high; it is suitable for oil and fat extraction of emulsified and embedded type sauce (salad dressing) rich in oil and fat, the extraction rate is high, the test peroxide value and acid value are not interfered by the pretreatment method, are more representative, solve the problem that the oil and fat in emulsified and embedded type sauce rich in oil and fat is not easy to separate and extract, the acid hydrolysis and alkali hydrolysis methods for testing the peroxide value and acid value have a great influence, the one-time simultaneous monitoring of the three physical and chemical indexes of the fat content, peroxide value and acid value can be simultaneously satisfied, the efficiency is high, it is more suitable for tracking monitoring in the production process of enterprises, improves the production efficiency of enterprises, and reduces the production cost of enterprises.

Description

Technical Field

[0001] This invention belongs to the field of food technology, and specifically relates to a method for extracting oil from sauces while simultaneously determining fat content, peroxide value, and acid value. Background Technology

[0002] China boasts a long history of culinary culture, and with social development, dishes have become increasingly diverse, and ways of eating have become more varied. The condiment industry related to food has also flourished, giving rise to a wide variety of sauces. In recent years, with the development of convenience foods and the surge in condiment varieties, people have become more aware of product quality and safety. Some sauces are rich in oil, and the stability of the amount of oil added to their formula is crucial to ensuring product quality. At the same time, the peroxide value and acid value of the oil have become key control points for evaluating product quality and safety.

[0003] Currently, the market offers sauces rich in oil-emulsified encapsulated oils (e.g., salad dressing ingredients: water, soybean oil, white sugar, vinegar, egg yolk liquid (containing protein, phospholipids, etc.), acid-treated starch, hydroxypropyl distarch phosphate, xanthan gum, citric acid, salt, spices, etc.), with oil content as high as 30-50%. Raw materials with emulsifying and thickening properties ensure a stable oil-emulsified encapsulation system within the product, effectively guaranteeing the product's emulsified encapsulation system stability for up to 9 months. While this stable encapsulation system guarantees product quality, it poses significant challenges to subsequent product validation and monitoring. Current testing methods cannot meet the testing requirements and lack the speed and efficiency to monitor and track product production.

[0004] Current research on oil extraction methods and peroxide value and acid value mainly focuses on milk powder and non-dairy creamer. Information on extraction rate verification for monitoring oil content during production is limited, and methods that simultaneously meet the requirements for extraction rate, peroxide value, and acid value are even rarer. For example, patent application CN105950285A discloses a method for extracting fat from dairy products and determining the peroxide value of fat, using dairy products with ethanol, water, and petroleum ether, allowing it to stand (12 hours), filtering, and rotary evaporating to obtain fat. Patent CN105572115A describes a method for extracting fat from non-dairy creamer and determining its peroxide value, using non-dairy creamer mixed with water and hydrochloric acid, acid-hydrolyzing at 70-80°C for 1 hour to obtain the acid-hydrolyzed product; mixing with ethanol and ether, allowing it to stand for at least 12 hours; evaporating the ether layer to obtain fat. Patent application CN102519957A discloses a method for detecting the peroxide value of milk powder, using water, ethanol, and ether to extract oil. Patent application CN 106908567 B discloses a method for determining the peroxide value of fats in infant formula milk powder, employing magnetic stirring, ultrasound, centrifugation, and collecting the upper organic phase by rotary evaporation to obtain the fat. Patent application CN 109813709 A discloses a method for determining the acid value and peroxide value of puffed foods, employing extraction by soaking pulverized particles in petroleum ether, centrifugation, and distillation to obtain the oil. Patent application CN111650014 A discloses a method for extracting oil samples for determining the peroxide value and acid value of oily foods, employing extraction by soaking granular samples in petroleum ether, filtration, and evaporation of the solvent to obtain the oil. There is almost no relevant research on oil-rich emulsified encapsulated sauces (such as salad dressings). Summary of the Invention

[0005] To address the shortcomings and deficiencies of the existing technology, the primary objective of this invention is to provide a method for simultaneously extracting oil from sauces and determining its fat content, peroxide value, and acid value. This method can be used for extracting oil from oil-rich emulsified sauces (such as salad dressing) and determining their fat content, peroxide value, and acid value. The method employs water dilution to reduce sauce viscosity, sodium chloride to alter the charge balance of the emulsified sauce system, and the addition of ethanol to reduce the emulsifying and embedding properties of emulsifiers, proteins, thickeners, and other auxiliary materials. Petroleum ether is used for stepwise extraction, followed by dehydration with anhydrous sodium sulfate, and the preparation of oil using vacuum rotary evaporation and nitrogen blowing. The method can determine the fat content (monitoring the stability of the product formulation), peroxide value, and acid value (monitoring the product's quality stability). The entire process is simple to operate, uses readily available instruments, has a short testing cycle, and is highly efficient, making it more suitable for continuous monitoring during enterprise production.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A method for simultaneously extracting oil from sauces and determining its fat content, peroxide value, and acid value includes the following steps:

[0008] (1) Add 0.5-3 times the weight of water to the sauce and stir at 500-2000 r / min for 2-5 min to disperse evenly to obtain a suspension; the sauce is an oil-rich emulsified and encapsulated sauce;

[0009] (2) Under stirring conditions of 500-1000 r / min, add 2-5% salt (by mass of suspension) to dissolve completely;

[0010] (3) Add 1-3 times the volume of 95% ethanol of the sauce and stir at 500-1000 r / min for 2-5 min to mix and disperse evenly.

[0011] (4) First extraction: Add 1-3 times the weight of the sauce to petroleum ether, stir at 500-1000 r / min for 2-5 min to mix and disperse evenly, let stand for 10-15 min, and three layers will appear from top to bottom: petroleum ether oil phase layer, sauce emulsion layer and aqueous phase layer. Use a pipette to remove the upper petroleum ether oil phase layer, leaving the sauce emulsion layer and aqueous phase layer liquid;

[0012] Second extraction: Add 1-1.5 times the weight of the sauce to the remaining emulsion and aqueous phase of the sauce from the first extraction. Stir at 300-700 rpm for 2-5 minutes to mix and disperse evenly. Let stand for 5-10 minutes. Three layers will appear from top to bottom: petroleum ether oil phase, sauce emulsion, and aqueous phase. Use a pipette to remove the upper petroleum ether oil phase, leaving the sauce emulsion and aqueous phase.

[0013] Third extraction: Add 0.5-1.0 times the weight of the sauce to the remaining emulsion and aqueous phase of the sauce from the second extraction. Stir at 300-700 rpm for 2-5 minutes to mix and disperse evenly. Let stand for 5-10 minutes. Three layers will appear from top to bottom: petroleum ether oil phase, sauce emulsion, and aqueous phase. Use a pipette to remove the upper petroleum ether oil phase. Combine the petroleum ether oil phases obtained from the first, second, and third extractions to obtain a petroleum ether oil mixture.

[0014] (5) Filter the petroleum ether oil mixture obtained in step (4) through an anhydrous sodium sulfate funnel, collect it into a constant weight recovery bottle, and then rinse the filter paper and funnel with 5-20 mL of blank petroleum ether to collect the dehydrated petroleum ether oil mixture.

[0015] (6) The dehydrated petroleum ether oil mixture obtained in step (5) is subjected to vacuum rotary evaporation at a temperature of 25-40℃ and a vacuum degree of -0.04 to -0.09 MPa. The petroleum ether is recovered by using a condenser at -5 to -20℃ until no petroleum ether drips from the condenser and the oil has no petroleum ether odor. Then, the rotary evaporation is continued for 5-10 minutes to further reduce solvent residue and the oil is recovered in the bottle.

[0016] (7) Wipe the surface of the recycling bottle several times, and then blow it with nitrogen gas at a pressure of 0.01-0.2Mpa for 5-30 minutes to further reduce the solvent residue in the grease, and reduce the impact of high temperature oxidation while cooling the grease to room temperature under nitrogen protection.

[0017] (8) Test the fat content, peroxide value and acid value of the oil after nitrogen blowing in step (7).

[0018] The petroleum ethers mentioned in steps (4) and (5) are both petroleum ethers with a boiling range of 30-60℃.

[0019] The fat content test described in step (7) is performed according to the following formula:

[0020] Fat content = (mass of extracted oil / mass of sauce sample) x 100%;

[0021] Oil extraction rate = (mass of recovered bottle and extracted oil - mass of recovered bottle) / amount of oil added x 100%;

[0022] The amount of oil added = the mass of the sauce sample x the theoretical oil content of the sauce.

[0023] The peroxide value mentioned in step (7) is tested according to the test method of the sample in GB5009.227-2016; the acid value is tested according to the test method of the sample in GB5009.229-2016.

[0024] The oil-rich emulsified encapsulated sauce in step (1) is salad dressing, and the water is RO water; the salt in step (2) is non-iodized salt or NaCl.

[0025] The anhydrous sodium sulfate funnel in step (5) contains 10-30% anhydrous sodium sulfate, which accounts for 10-30% of the theoretical mass of oil in the sauce.

[0026] Step (7) involves wiping the surface of the recycling bottle multiple times. First, wipe the surface of the recycling bottle with dry gauze to remove moisture. Then, wipe the surface of the recycling bottle with gauze soaked in anhydrous ethanol. Finally, wipe the surface of the recycling bottle with dry gauze to remove any remaining ethanol.

[0027] The principle of this invention:

[0028] This invention reduces the viscosity of thickeners, emulsifiers, proteins, and other additives in sauces by diluting them with water.

[0029] This invention alters the charge balance of the emulsified sauce system by adding sodium chloride, thereby reducing its emulsification and encapsulation properties.

[0030] This invention further disrupts the balance of emulsifying and encapsulating properties of excipients such as emulsifiers, proteins, and thickeners by adding ethanol.

[0031] This invention utilizes a single solvent, petroleum ether, for stepwise extraction, ensuring the extraction rate of oils and meeting the requirements for fat content testing.

[0032] This invention removes trace amounts of moisture by filtering with anhydrous sodium sulfate, thus reducing interference with subsequent tests.

[0033] This invention removes single organic solvents by vacuum rotary evaporation (the solvent can be reused), reducing the impact of aerobic, high-temperature, and long-term exposure on oils and fats.

[0034] This invention reduces solvent residue in the oil by wiping the recovery bottle with anhydrous ethanol and then blowing it with nitrogen. On the other hand, it reduces the impact of high-temperature oxidation by extracting the oil under nitrogen protection and cooling it to room temperature (ensuring that the fat content, peroxide value and acid value of the prepared sample are more representative).

[0035] The present invention has the following advantages and effects compared with the prior art:

[0036] This invention is simple to operate and uses simple instruments; it has a short testing cycle and high efficiency; it is suitable for oil extraction from oil-rich emulsified and encapsulated sauces (salad dressings), with a high extraction rate. The results of testing peroxide value and acid value are not affected by pretreatment methods and are more representative. It solves the problem that oil is difficult to separate and extract from oil-rich emulsified and encapsulated sauces, and that acid hydrolysis and alkaline hydrolysis methods have a significant impact on the testing of peroxide value and acid value. It can simultaneously monitor three physicochemical indicators—fat content, peroxide value, and acid value—at one time, which is highly efficient and more suitable for tracking and monitoring during enterprise production processes. Attached Figure Description

[0037] Figure 1 A comparison chart showing the color differences of oils extracted using different methods. Detailed Implementation

[0038] The following specific embodiments further illustrate the content of the present invention, but should not be construed as limiting the present invention.

[0039] Example 1

[0040] (1) Add 160g of RO water to 80.35g of salad dressing (theoretically containing 40% fat by mass), stir at 1000r / min for 3min to disperse evenly, and obtain a suspension; under stirring at 1000r / min, slowly add 3% salt by mass of the suspension and dissolve it completely; then slowly add 95% ethanol by volume, twice the mass of the dressing, and stir at 1000r / min for 3min to mix and disperse evenly.

[0041] (2) First extraction: Slowly add petroleum ether (boiling range 30-60℃) twice the weight of the sauce, stir at 1000r / min for 3min to mix and disperse evenly, let stand for 15min, and three layers will appear from top to bottom: petroleum ether oil phase layer, sauce emulsion layer and aqueous phase layer. Use a pipette to remove the upper petroleum ether oil phase layer, leaving the sauce emulsion layer and aqueous phase layer liquid;

[0042] Second extraction: Add petroleum ether (boiling range 30-60℃) at 1 times the weight of the sauce to the remaining emulsion layer and aqueous phase layer of the sauce from the first extraction. Stir at 500 r / min for 3 min to mix and disperse evenly. Let stand for 10 min. Three layers will appear from top to bottom: petroleum ether oil phase layer, sauce emulsion layer and aqueous phase layer. Use a pipette to remove the upper petroleum ether oil phase layer, leaving the sauce emulsion layer and aqueous phase layer.

[0043] Third extraction: Add 0.5 times the weight of the sauce (boiling range 30-60℃) of petroleum ether to the remaining sauce emulsion layer and aqueous phase layer from the second extraction. Stir at 500 r / min for 3 min to mix and disperse evenly. Let stand for 10 min, and three layers will appear from top to bottom: petroleum ether oil phase layer, sauce emulsion layer, and aqueous phase layer. Use a pipette to remove the upper petroleum ether oil phase layer. Combine the petroleum ether oil phase layers obtained from the first, second, and third extractions to obtain a petroleum ether oil mixture.

[0044] (3) The petroleum ether oil mixture obtained in step (2) is filtered through an anhydrous sodium sulfate funnel (containing anhydrous sodium sulfate accounting for 20% of the theoretical mass of oil in the sauce), collected into a constant weight recovery bottle (118.14g), and then the filter paper and funnel are rinsed with 15mL of blank petroleum ether to collect the dehydrated petroleum ether oil mixture.

[0045] (4) The dehydrated petroleum ether oil mixture obtained in step (3) is subjected to vacuum rotary evaporation at 35°C and -0.09 MPa. The petroleum ether is recovered using a -12°C condenser until no petroleum ether drips from the condenser and the oil has no petroleum ether odor. Then, the rotary evaporation continues for 8 minutes to further reduce solvent residue and the oil is recovered from the bottle.

[0046] (5) Wipe the surface of the recycling bottle multiple times (wiping the surface of the recycling bottle multiple times involves first wiping the surface moisture with a dry gauze, then wiping the surface with a gauze soaked in anhydrous ethanol, and then wiping the surface with a dry gauze to remove any remaining ethanol), and then blow it with 0.1 MPa nitrogen gas for 20 minutes to further reduce the solvent residue in the grease, and reduce the impact of high-temperature oxidation while cooling the grease to room temperature under nitrogen protection; cool, and weigh the recycling bottle containing the grease at this time as 148.85g;

[0047] (6) Test the fat content, peroxide value and acid value of the oil after nitrogen blowing in step (5).

[0048] The fat content was calculated as (148.85-118.14) / 80.35*100% = 38.22% [Oil extraction rate = (148.85-118.14) / (80.35*0.4)*100% = 95.55%], and the oil was a transparent, light yellow color.

[0049] The tested peroxide value was 0.046 g / 100 g (tested according to the test method for the sample in GB5009.227-2016);

[0050] The tested acid value was 0.52 mg / g (tested according to the test method for the sample in GB5009.229-2016).

[0051] Example 2

[0052] (1) Add 160g of RO water to 80.40g of salad dressing (theoretically containing 40% fat by mass), stir at 1000r / min for 3min to disperse evenly, and obtain a suspension; under stirring at 1000r / min, slowly add 5% salt by mass of the suspension and dissolve it completely; then slowly add 95% ethanol by volume, twice the mass of the dressing, and stir at 1000r / min for 3min to mix and disperse evenly.

[0053] (2) First extraction: Slowly add 2.5 times the weight of the sauce with petroleum ether (boiling range 30-60℃), stir at 1000r / min for 3min to mix and disperse evenly, let stand for 15min, and three layers will appear from top to bottom: petroleum ether oil phase layer, sauce emulsion layer and aqueous phase layer. Use a pipette to remove the upper petroleum ether oil phase layer, leaving the sauce emulsion layer and aqueous phase layer liquid;

[0054] Second extraction: Add petroleum ether (boiling range 30-60℃) at 1 times the weight of the sauce to the remaining emulsion layer and aqueous phase layer of the sauce from the first extraction. Stir at 500 r / min for 3 min to mix and disperse evenly. Let stand for 10 min. Three layers will appear from top to bottom: petroleum ether oil phase layer, sauce emulsion layer and aqueous phase layer. Use a pipette to remove the upper petroleum ether oil phase layer, leaving the sauce emulsion layer and aqueous phase layer.

[0055] Third extraction: Add petroleum ether (boiling range 30-60℃) at 1 times the weight of the sauce to the remaining emulsion layer and aqueous phase layer from the second extraction. Stir at 500 r / min for 3 min to mix and disperse evenly. Let stand for 10 min, and three layers will appear from top to bottom: petroleum ether oil phase layer, sauce emulsion layer, and aqueous phase layer. Use a pipette to remove the upper petroleum ether oil phase layer. Combine the petroleum ether oil phase layers obtained from the first, second, and third extractions to obtain a petroleum ether oil mixture.

[0056] (3) The petroleum ether oil mixture obtained in step (2) is filtered through an anhydrous sodium sulfate funnel (containing anhydrous sodium sulfate accounting for 20% of the theoretical mass of oil in the sauce), collected into a constant weight recovery bottle (112.12g), and then the filter paper and funnel are rinsed with 15mL of blank petroleum ether to collect the dehydrated petroleum ether oil mixture.

[0057] (4) The dehydrated petroleum ether oil mixture obtained in step (3) is subjected to vacuum rotary evaporation at 35°C and -0.09 MPa. The petroleum ether is recovered using a -12°C condenser until no petroleum ether drips from the condenser and the oil has no petroleum ether odor. Then, the rotary evaporation continues for 8 minutes to further reduce solvent residue and the oil is recovered from the bottle.

[0058] (5) Wipe the surface of the recycling bottle multiple times (wiping the surface of the recycling bottle multiple times involves first wiping the surface moisture with a dry gauze, then wiping the surface with a gauze soaked in anhydrous ethanol, and then wiping the surface with a dry gauze to remove any remaining ethanol), and then blow it with 0.1 MPa nitrogen gas for 20 minutes to further reduce the solvent residue in the grease, and reduce the impact of high-temperature oxidation while cooling the grease to room temperature under nitrogen protection; cool, and weigh the recycling bottle containing the grease at this time as 143.15g;

[0059] (6) Test the fat content, peroxide value and acid value of the oil after nitrogen blowing in step (5).

[0060] The fat content was calculated as (143.15-112.12) / 80.40*100% = 38.59%, and the oil extraction rate was calculated as (143.15-112.12) / (80.40*0.4)*100% = 96.49%. The oil was a transparent, light yellow color.

[0061] The tested peroxide value was 0.053 g / 100 g (tested according to the test method for the sample in GB5009.227-2016);

[0062] The tested acid value was 0.49 mg / g (tested according to the sample determination method in GB5009.229-2016).

[0063] Example 3

[0064] (1) Add 100g of RO water to 100.18g of compound sauce (theoretically containing 30% oil by mass), stir at 1000r / min for 3min to disperse evenly, and obtain a suspension; under stirring at 1000r / min, slowly add 4% of the mass of the suspension of salt and dissolve it completely; then slowly add 2.5 times the mass of the sauce of 95% ethanol by volume, stir at 1000r / min for 3min to mix and disperse evenly.

[0065] (2) First extraction: Slowly add 2.5 times the weight of the sauce with petroleum ether (boiling range 30-60℃), stir at 1000r / min for 3min to mix and disperse evenly, let stand for 15min, and three layers will appear from top to bottom: petroleum ether oil phase layer, sauce emulsion layer and aqueous phase layer. Use a pipette to remove the upper petroleum ether oil phase layer, leaving the sauce emulsion layer and aqueous phase layer liquid;

[0066] Second extraction: Add petroleum ether (boiling range 30-60℃) at 1 times the weight of the sauce to the remaining emulsion layer and aqueous phase layer of the sauce from the first extraction. Stir at 500 r / min for 3 min to mix and disperse evenly. Let stand for 10 min. Three layers will appear from top to bottom: petroleum ether oil phase layer, sauce emulsion layer and aqueous phase layer. Use a pipette to remove the upper petroleum ether oil phase layer, leaving the sauce emulsion layer and aqueous phase layer.

[0067] Third extraction: Add 0.5 times the weight of the sauce (boiling range 30-60℃) of petroleum ether to the remaining sauce emulsion layer and aqueous phase layer from the second extraction. Stir at 500 r / min for 3 min to mix and disperse evenly. Let stand for 10 min, and three layers will appear from top to bottom: petroleum ether oil phase layer, sauce emulsion layer, and aqueous phase layer. Use a pipette to remove the upper petroleum ether oil phase layer. Combine the petroleum ether oil phase layers obtained from the first, second, and third extractions to obtain a petroleum ether oil mixture.

[0068] (3) The petroleum ether oil mixture obtained in step (2) is filtered through an anhydrous sodium sulfate funnel (containing anhydrous sodium sulfate accounting for 15% of the theoretical mass of oil in the sauce), collected into a constant weight recovery bottle (115.36g), and then the filter paper and funnel are rinsed with 15mL of blank petroleum ether to collect the dehydrated petroleum ether oil mixture.

[0069] (4) The dehydrated petroleum ether oil mixture obtained in step (3) is subjected to vacuum rotary evaporation at 40°C and -0.08 MPa. The petroleum ether is recovered using a -15°C condenser until no petroleum ether drips from the condenser and the oil has no petroleum ether odor. Then, the rotary evaporation is continued for 10 minutes to further reduce solvent residue and the oil is recovered from the bottle.

[0070] (5) Wipe the surface of the recycling bottle multiple times (wiping the surface of the recycling bottle multiple times involves first wiping the surface moisture with a dry gauze, then wiping the surface with a gauze soaked in anhydrous ethanol, and then wiping the surface with a dry gauze to remove any remaining ethanol), and then blow it with 0.1 MPa nitrogen gas for 15 minutes to further reduce the solvent residue in the grease, and reduce the impact of high-temperature oxidation while cooling the grease to room temperature under nitrogen protection; cool, and weigh the recycling bottle containing the grease at this time as 144.12g;

[0071] (6) Test the fat content, peroxide value and acid value of the oil after nitrogen blowing in step (5).

[0072] The fat content was calculated as (144.12-115.36) / 100.18*100% = 28.71% [Oil extraction rate = (144.12-115.36) / 100.18*0.3*100% = 95.70%], and the oil was a transparent, light yellow color.

[0073] The tested peroxide value was 0.071 g / 100 g (tested according to the test method for the sample in GB5009.227-2016);

[0074] The tested acid value was 0.76 mg / g (tested according to the sample determination method in GB5009.229-2016).

[0075] Comparative Example 1

[0076] (1) First extraction: Add 2.5 times the weight of the sauce to 80.23g of salad dressing (theoretically containing 40% oil by mass) of petroleum ether (boiling range 30-60℃), stir at 1000r / min for 3min to disperse evenly, let stand for 15min, and two layers will appear from top to bottom: petroleum ether oil phase layer and salad dressing aqueous phase layer. Use a pipette to remove the upper petroleum ether oil phase layer, leaving the salad dressing aqueous phase layer;

[0077] Second extraction: Add petroleum ether (boiling range 30-60℃) equal to the weight of the salad dressing to the remaining aqueous phase of the salad dressing from the first extraction. Stir at 500 r / min for 3 min to mix and disperse evenly. Let stand for 5 min. Two layers will appear from top to bottom: a petroleum ether oil phase and a salad dressing aqueous phase. Use a pipette to remove the upper petroleum ether oil phase, leaving the salad dressing aqueous phase.

[0078] Third extraction: Add petroleum ether (boiling range 30-60℃) at a volume equal to the weight of the salad dressing aqueous phase remaining from the second extraction. Stir at 500 rpm for 3 minutes to mix and disperse evenly. Let stand for 5 minutes, resulting in two layers from top to bottom: a petroleum ether oil phase and a salad dressing aqueous phase. Use a pipette to remove the upper petroleum ether oil phase. Combine the petroleum ether oil phases obtained from the first, second, and third extractions to obtain a petroleum ether-oil mixture.

[0079] (2) The petroleum ether oil mixture obtained in step (1) is filtered through an anhydrous sodium sulfate funnel (containing anhydrous sodium sulfate accounting for 15% of the theoretical mass of oil in the sauce), collected into a constant weight recovery bottle, and then the filter paper and funnel are rinsed with 15 mL of blank petroleum ether to collect the dehydrated petroleum ether oil mixture.

[0080] (3) The dehydrated petroleum ether oil mixture obtained in step (2) was subjected to vacuum rotary evaporation at 35°C and -0.09 MPa. The petroleum ether was recovered using a -12°C condenser until no petroleum ether dripped from the condenser and the oil had no petroleum ether odor. Rotary evaporation was continued for another 8 minutes to further reduce solvent residue. The recovery bottle and almost no oil came out, and the subsequent tests for fat content, peroxide value and acid value could not be met.

[0081] Comparative Example 2

[0082] Test according to the acid hydrolysis method in GB5009.6-2016.

[0083] Remove the test tube and weigh 10.35g of the compound sauce (theoretically containing 30% fat by mass). Add 10mL of ethanol and mix. After cooling, transfer the mixture to a 100mL graduated cylinder with a stopper. Wash the test tube several times with 25mL of anhydrous ether, and pour the ether into the graduated cylinder. After all the anhydrous ether has been poured into the graduated cylinder, stopper the tube and shake for 1 minute. Carefully open the stopper to release the gas, then stopper the tube again and let it stand for 12 minutes. Carefully open the stopper again and rinse the stopper and the mouth of the graduated cylinder with ether to remove any fat adhering to them. Let it stand for 10-20 minutes until the upper liquid is clear. Aspirate the supernatant into a pre-weighed conical flask, add 5mL of anhydrous ether to the stoppered graduated cylinder, shake, and let it stand. Again, aspirate the upper ether and transfer it to a receiving flask (118.25g).

[0084] Remove the receiving bottle and recover anhydrous diethyl ether or petroleum ether. When 1 mL to 2 mL of solvent remains in the receiving bottle, evaporate it to dryness in a water bath, then dry it at 100℃±5℃ for 1 hour. After cooling in a desiccator for 0.5 hours, weigh it (121.24 g).

[0085] The fat content was calculated as (121.24-118.25) / 10.35*100% = 28.89% [Oil extraction rate = (121.24-118.25) / 10.35*0.3*100% = 96.45%], and the oil was transparent with a slightly dark brownish-yellow hue.

[0086] The tested peroxide value was 0.11 g / 100 g (tested according to the test method for samples in GB5009.227-2016).

[0087] The tested acid value was 3.21 mg / g (tested according to the sample determination method in GB5009.229-2016).

[0088] Comparative Example 3

[0089] Test according to the alkaline hydrolysis method in GB5009.6-2016.

[0090] Weigh 10.64g of the compound sauce (theoretically containing 30% fat by mass) into a fat extraction bottle, add 2.0mL of ammonia water, mix thoroughly, and immediately place the fat extraction bottle into a water bath at 65℃±5℃. Heat for 15min~20min, shaking occasionally. After removing, cool to room temperature and let stand for 30s.

[0091] Extraction: 1) Add 10 mL of ethanol and mix gently but thoroughly, avoiding bringing the liquid too close to the neck of the bottle. If necessary, add 2 drops of Congo red solution. 2) Add 25 mL of diethyl ether, stopper the bottle, and hold the liposuction bottle horizontally with the extended part of the bulb facing upwards, clamping it onto a shaker. Shake at approximately 100 times / min for 1 minute, or manually shake. However, care should be taken to avoid forming a persistent emulsion. After the liposuction bottle has cooled, carefully open the stopper and rinse the stopper and neck of the bottle with a small amount of the mixed solvent, allowing the rinsing solution to flow into the liposuction bottle. 3) Add 25 mL of petroleum ether, stopper the bottle with a re-wetted stopper, and gently shake for 30 seconds as described in 2). 4) Place the stoppered liposuction bottle in a centrifuge and centrifuge at 500-600 rpm for 5 minutes. Otherwise, allow the liposuction bottle to stand for at least 30 minutes until the supernatant is clear and visibly separated from the aqueous phase. 5) Carefully open the stopper and rinse the stopper and the inner wall of the bottle neck with a small amount of mixed solvent, allowing the rinsing solution to flow into the liposuction bottle. If the interface between the two phases is lower than the point where the bulb meets the bottle body, slowly add water along the edge of the bottle wall until the liquid level is higher than the point where the bulb meets the bottle body for easy pouring. 6) Pour the upper layer of liquid as much as possible into the prepared fat collection bottle containing zeolite, avoiding pouring out the water layer. 7) Rinse the outside of the bottle neck with a small amount of mixed solvent, collecting the rinsing solution in the fat collection bottle. Prevent solvent from splashing onto the outside of the liposuction bottle. 8) Add 5 mL of ethanol to the liposuction bottle and rinse the inner wall of the bottle neck with ethanol, mixing as described in 1). Repeat steps 2)–7), using 15 mL of anhydrous diethyl ether and 15 mL of petroleum ether for a second extraction. 9) Repeat steps 17.2.2–17.2.7), using 15 mL of anhydrous diethyl ether and 15 mL of petroleum ether for a third extraction.

[0092] Combine all extracts into a collection bottle (185.73g). Remove the solvent from the fat collection bottle by distillation. Before distillation, rinse the inside of the neck of the bottle with a small amount of mixed solvent. Place the fat collection bottle in an oven at 100℃±5℃ and dry for 1 hour. After removing it, place it in a desiccator to cool for 0.5 hours and weigh it (188.78g).

[0093] The fat content of the test sample was calculated as (188.78-185.73) / 10.64*100% = 28.67% [Oil extraction rate = (188.78-185.73) / 10.64*0.3*100% = 95.61%]. The oil was transparent, light yellow with a slight bluish tinge.

[0094] The tested peroxide value was 0.13 g / 100 g (tested according to the test method for samples in GB5009.227-2016).

[0095] The acid value was not detected (tested according to the test method for the sample in GB5009.229-2016).

[0096] Figure 1 Comparative Figure 3 shows the color differences of oils extracted using different methods in Example 3, Comparative Example 2, and Comparative Example 3.

[0097] Example 3 uses an efficient and gentle method to extract oils: on the one hand, the appearance color is light yellow, which is similar to the color of the oils added to the product formula, and the sensory characteristics are not affected by the extraction method; on the other hand, the tested acid value and peroxide value are not affected by the extraction method, making them more scientific and representative.

[0098] Compared with the acid hydrolysis method used in Example 2, the oil extraction rate can be guaranteed. However, the residues from acid hydrolysis interfere with the peroxide value and acid value tests to varying degrees. The extracted oil is significantly darker in color, and although the peroxide value is within a controllable range, it is relatively high. However, the acid value is significantly higher, making the data unreliable.

[0099] Compared with the alkaline hydrolysis method used in Example 3, the oil extraction rate can be guaranteed. The residues from alkaline hydrolysis interfere with the peroxide value and acid value tests to varying degrees. The extracted oil is darker in color, and although the peroxide value is within a controllable range, it is relatively high. However, the acid value cannot be directly tested.

[0100] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for simultaneously extracting oil from sauces and determining its fat content, peroxide value, and acid value, characterized in that... The following steps are included: (1) Add 0.5-3 times the weight of water to the sauce and stir at 500-2000 r / min for 2-5 min to disperse evenly to obtain a suspension; the sauce is a fat-rich emulsified encapsulated sauce; the fat-rich emulsified encapsulated sauce is salad dressing; (2) Under stirring conditions of 500-1000 r / min, add 2-5% salt (by mass of suspension) and dissolve completely; (3) Add 1-3 times the volume of 95% ethanol of the sauce and stir at 500-1000 r / min for 2-5 min to mix and disperse evenly; (4) First extraction: Add 1-3 times the weight of the sauce to petroleum ether, stir at 500-1000 r / min for 2-5 min to mix and disperse evenly, let stand for 10-15 min, and three layers will appear from top to bottom: petroleum ether oil phase layer, sauce emulsion layer and aqueous phase layer. Use a pipette to remove the upper petroleum ether oil phase layer, leaving the sauce emulsion layer and aqueous phase layer liquid; Second extraction: Add 1-1.5 times the weight of the sauce to the remaining emulsion and aqueous phase of the sauce from the first extraction. Stir at 300-700 rpm for 2-5 minutes to mix and disperse evenly. Let stand for 5-10 minutes. Three layers will appear from top to bottom: petroleum ether oil phase, sauce emulsion, and aqueous phase. Use a pipette to remove the upper petroleum ether oil phase, leaving the sauce emulsion and aqueous phase. Third extraction: Add 0.5-1.0 times the weight of the sauce to the remaining emulsion and aqueous phase of the sauce from the second extraction. Stir at 300-700 rpm for 2-5 minutes to mix and disperse evenly. Let stand for 5-10 minutes. Three layers will appear from top to bottom: petroleum ether oil phase, sauce emulsion, and aqueous phase. Use a pipette to remove the upper petroleum ether oil phase. Combine the petroleum ether oil phases obtained from the first, second, and third extractions to obtain a petroleum ether oil mixture. (5) Filter the petroleum ether oil mixture obtained in step (4) through an anhydrous sodium sulfate funnel, collect it in a recovery bottle, rinse the filter paper and funnel with 5-20 mL of petroleum ether, and collect the dehydrated petroleum ether oil mixture. (6) The dehydrated petroleum ether oil mixture obtained in step (5) is subjected to vacuum rotary evaporation at a temperature of 25-40℃ and a vacuum degree of -0.04~-0.09MPa. The petroleum ether is recovered by using a condenser at -5~-20℃ until no petroleum ether drips from the condenser and the oil has no petroleum ether odor. Then, the rotary evaporation is continued for 5-10 minutes to further reduce the solvent residue and the oil is recovered in the bottle. (7) Wipe the surface of the recycling bottle several times, and then blow it with nitrogen gas at a pressure of 0.01-0.2Mpa for 5-30 minutes to further reduce the solvent residue in the grease, and reduce the impact of high temperature oxidation while cooling the grease to room temperature under nitrogen protection. (8) Test the fat content, peroxide value and acid value of the oil after nitrogen pressure blowing in step (7).

2. The method for extracting oil from sauces and simultaneously determining fat content, peroxide value, and acid value according to claim 1, characterized in that: The petroleum ethers mentioned in steps (4) and (5) are both petroleum ethers with a boiling range of 30-60℃.

3. The method for extracting oil from sauces and simultaneously determining fat content, peroxide value, and acid value according to claim 1, characterized in that: The fat content test in step (8) is performed according to the following formula: Fat content = (mass of extracted oil / mass of sauce sample) × 100%.

4. The method for extracting oil from sauces and simultaneously determining fat content, peroxide value, and acid value according to claim 1, characterized in that: The peroxide value in step (8) is tested according to the test method of the sample in GB5009.227-2016; the acid value is tested according to the test method of the sample in GB5009.229-2016.

5. The method for extracting oil from sauces and simultaneously determining fat content, peroxide value, and acid value according to claim 1, characterized in that: The water mentioned in step (1) is RO water.

6. The method for extracting oil from sauces and simultaneously determining fat content, peroxide value, and acid value according to claim 1, characterized in that: Step (7) involves wiping the surface of the recycling bottle multiple times. First, wipe the surface of the recycling bottle with dry gauze to remove moisture, then wipe the surface of the recycling bottle with gauze soaked in anhydrous ethanol, and finally wipe the surface of the recycling bottle with dry gauze to remove any remaining ethanol.

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