How to identify adulterated feed ingredients? A few simple methods to teach you
Simple identification methods for adulteration in several feed ingredients
I. Basic common knowledge for identifying adulterated feed ingredients
1. Use the four methods of smelling, touching, looking and tasting to distinguish them.
1.1 Smell: specific feed ingredients all have their own particular fragrant odor. If there is an off odor, strange odor, moldy odor or no odor (adulteration can mask the fragrant odor), it shows that the feed is a fake or inferior ingredient.
1.2 Touch: because the human body carries bioelectricity, you can repeatedly thrust your hand into the feed ingredient, then pull it out and shake it off. If fine substances are not easy to shake off, it shows there is adulteration.
1.3 Look: ① Whether the color is consistent. A specific feed ingredient has its own inherent luster. If in the same batch of ingredients there are substances with different colors and different degrees of luster, it shows there is adulteration; ② Whether the particle size is uniform. Check whether the ingredient with relatively fine particle size contains relatively uniform fine particles or whether ultra-fine substances are present, and in a certain quantity. If so, you can break them down and compare with the specific ingredient, and you will know at once by comparison.
1.4 Taste: specific ingredients all have a fixed taste, such as sweet, sour, astringent, bitter, fragrant, etc. If you taste often, you will know the differences; especially stone powder, zeolite, sand and gravel, etc., you will know at once by tasting.
II. Examples of identifying adulteration in some common feed ingredients
1. Soybean meal. Dealers often use large bran flakes, rice hulls, rice bran, etc. mixed with ground loess and cornmeal to make fine particles, then color them to make "soybean meal material". Some also use only ground loess made into granules and colored, mixed into soybean meal, causing the crude protein content of the soybean meal to drop below 30%.
Identification: ① Smell. Soybean meal mixed with "soybean meal material" changes from a strong fragrance to a faint fragrance or no fragrance at all. ② Look. Soybean meal is pale yellow, and dark yellow when heated at a high temperature. The unadulterated one has very obvious luster and is uniform and neat, while soybean meal mixed with "soybean meal material" has reduced overall luster, especially the "soybean meal material", which basically has no luster; after removing the neat, relatively large particles, take what remains, the fine particles, then pick them up with the right index finger and thumb and rub hard, and you will know at once by looking. True soybean meal, even the finest particles, cannot be rubbed fine with two fingers. ③ Taste. Real soybean meal has a bean fragrance, while the adulterated one has no taste (cornmeal, stone powder, etc.) or an earthy taste (mixed with loess, mud and sand, etc.). ④ Water soaking. Take an appropriate amount of sample and put it into a large glass, soak it in water for 2 hours, then stir gently with a small stick. If there is layering, the upper layer is soybean meal, the middle layer is cornmeal (cake), and the lower layer is loess, calcium powder, stone powder, etc. ⑤ Dropping iodine solution. Take a small amount of sample and place it on a glass slide, drop a few drops of iodine solution on the sample, and after 1 minute, if any substance turns blue-black, it proves that corn, bran, rice hull, etc. have been mixed in.
2. Cottonseed meal. It is mainly adulterated with red soil, bentonite, brown zeolite powder or sand powder, and some also use calcium powder, various colored soils, bran, rice bran, rice hulls processed into granules and colored to make "cottonseed meal material".
Identification: because cottonseed meal comes from different producing areas and the processing technological process is different, the color and quality of the produced cottonseed meal also differ. It should be analyzed according to the specific situation. Using sensory inspection together with the water soaking method for identification is relatively easy and also relatively accurate.
3. Fish meal. It is often adulterated with feather meal, blood meal, leather meal, corn gluten meal, wheat middlings, fish oil, bone meal, shell powder, urea, ammonium salts, etc.
Identification: ① Smell. Good-quality fish meal has a faint fish fragrance, without a fishy smell, strange odor or pungent ammonia smell. ② Look. It varies with the place of origin (Peru, Japan, Russia, China's coastal waters) and fish species (Peruvian sardine, Japanese sardine, Russian white fish, China's coastal anchovy, etc.) and processing technology, but the color and luster are consistent and the particle size is consistent. You can see a large amount of loose fish muscle fibers, a small amount of fish eyes, fish bones and fish scales. ③ Taste. Good fish meal tastes of fish fragrance in the mouth without a strange taste and dissolves easily in the mouth, while the adulterated one does not dissolve at all. ④ Water soaking. Put a small amount of fish meal into a glass filled with water and stir gently with a small stick. Good-quality fish meal quickly sinks to the bottom of the glass, the water is clear, and there is no floating matter, but low-quality or adulterated fish meal makes the water turbid after stirring, settles slowly, and there is also floating matter on top. If there are many kinds and large amounts of adulterants, they can be reflected at different layers. ⑤ Odor detection. Put an appropriate amount of sample into a sealed heatable container (preferably a stoppered Erlenmeyer flask) and heat for 15 minutes, then open the lid. If an ammonia smell can be smelled, it shows that urea has been mixed in.
4. Bone granule powder. It is often adulterated with shell powder, zeolite powder, fine sand, etc.
Identification: to identify bone granules, just separate the large particles from the fine powdery matter, then carefully observe the fine matter and you can see it. ① Pure bone powder has its own inherent odor, while adulterated bone powder has this odor reduced or very slight. ② Pure bone powder is grayish-white fine granular powder in color, while adulterated bone powder is whitish or dark in color. ③ Take a small amount of sample and put it into a test tube, hold it over a fire and burn it. Bone powder produces steam, then produces a pungent smell of burning hair. Adulterated bone powder produces little steam and odor, or even no steam or odor. ④ Take a small amount of sample and put it into dilute hydrochloric acid. Pure bone powder will give out a short "shasha" sound, the particle surface does not produce bubbles, and finally it all dissolves and becomes turbid, while adulterated bone powder has no such sound phenomenon.
5. Amino acids (mainly methionine and lysine) are often adulterated with starch, glucose, stone powder, etc.
Identification: methionine is pure white or pale yellow crystals, lustrous, with a sweet taste when tasted. The adulterant is fine powdery matter, low in luster, with a strange taste and astringent feel when tasted. Lysine is milky white or pale yellowish-brown granular crystals or fine powdery matter, low in luster, with a sour taste when tasted, and the sour taste decreases after adulteration. A dissolution method can be used for identification. Take 1 g of sample and dissolve it in 50 ml of distilled water. If it can all dissolve, it is genuine. If there is a small amount of insoluble matter at the bottom of the bottle or suspended matter in the water, it is fake.
6. Bran. It is often adulterated with rice chaff, peanut chaff, sawdust, talc powder, calcium powder, etc.
Identification: gently tap the packaging containing the bran with your hand. If fine white powder pops out, it proves that talc powder or calcium powder has been mixed in; thrust your hand into the bran, then pull it out. If white powder sticks to your hand, what is easy to shake off is residual flour, and what is not easy to shake off is talc powder or calcium powder; grab a handful of bran with your hand and rub it hard. If it forms a lump, it is pure bran. If your hand feels swollen, suspect that there are rice hulls, sawdust or peanut chaff.
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Learned it, thanks for sharing
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Reply to 2#fongsong007
You're welcome, let's make progress together!
--------------------------------------
Bro! Which class year at Nanjing Agricultural University are you from??
--------------------------------------
Learned it, thanks for sharing, very practical
--------------------------------------
There's no method for identifying feed.. I really want to know how to identify whether feed is good or bad...
--------------------------------------
Good stuff for everyone to use
--------------------------------------
Good stuff, thanks to the original poster for providing it!
--------------------------------------
Learned it...
--------------------------------------
Thanks for the hard work, very good material
--------------------------------------
Good material! Thanks!
--------------------------------------
Good material, bookmarked
1. Use the four methods of smelling, touching, looking and tasting to distinguish them.
1.1 Smell: specific feed ingredients all have their own particular fragrant odor. If there is an off odor, strange odor, moldy odor or no odor (adulteration can mask the fragrant odor), it shows that the feed is a fake or inferior ingredient.
1.2 Touch: because the human body carries bioelectricity, you can repeatedly thrust your hand into the feed ingredient, then pull it out and shake it off. If fine substances are not easy to shake off, it shows there is adulteration.
1.3 Look: ① Whether the color is consistent. A specific feed ingredient has its own inherent luster. If in the same batch of ingredients there are substances with different colors and different degrees of luster, it shows there is adulteration; ② Whether the particle size is uniform. Check whether the ingredient with relatively fine particle size contains relatively uniform fine particles or whether ultra-fine substances are present, and in a certain quantity. If so, you can break them down and compare with the specific ingredient, and you will know at once by comparison.
1.4 Taste: specific ingredients all have a fixed taste, such as sweet, sour, astringent, bitter, fragrant, etc. If you taste often, you will know the differences; especially stone powder, zeolite, sand and gravel, etc., you will know at once by tasting.
II. Examples of identifying adulteration in some common feed ingredients
1. Soybean meal. Dealers often use large bran flakes, rice hulls, rice bran, etc. mixed with ground loess and cornmeal to make fine particles, then color them to make "soybean meal material". Some also use only ground loess made into granules and colored, mixed into soybean meal, causing the crude protein content of the soybean meal to drop below 30%.
Identification: ① Smell. Soybean meal mixed with "soybean meal material" changes from a strong fragrance to a faint fragrance or no fragrance at all. ② Look. Soybean meal is pale yellow, and dark yellow when heated at a high temperature. The unadulterated one has very obvious luster and is uniform and neat, while soybean meal mixed with "soybean meal material" has reduced overall luster, especially the "soybean meal material", which basically has no luster; after removing the neat, relatively large particles, take what remains, the fine particles, then pick them up with the right index finger and thumb and rub hard, and you will know at once by looking. True soybean meal, even the finest particles, cannot be rubbed fine with two fingers. ③ Taste. Real soybean meal has a bean fragrance, while the adulterated one has no taste (cornmeal, stone powder, etc.) or an earthy taste (mixed with loess, mud and sand, etc.). ④ Water soaking. Take an appropriate amount of sample and put it into a large glass, soak it in water for 2 hours, then stir gently with a small stick. If there is layering, the upper layer is soybean meal, the middle layer is cornmeal (cake), and the lower layer is loess, calcium powder, stone powder, etc. ⑤ Dropping iodine solution. Take a small amount of sample and place it on a glass slide, drop a few drops of iodine solution on the sample, and after 1 minute, if any substance turns blue-black, it proves that corn, bran, rice hull, etc. have been mixed in.
2. Cottonseed meal. It is mainly adulterated with red soil, bentonite, brown zeolite powder or sand powder, and some also use calcium powder, various colored soils, bran, rice bran, rice hulls processed into granules and colored to make "cottonseed meal material".
Identification: because cottonseed meal comes from different producing areas and the processing technological process is different, the color and quality of the produced cottonseed meal also differ. It should be analyzed according to the specific situation. Using sensory inspection together with the water soaking method for identification is relatively easy and also relatively accurate.
3. Fish meal. It is often adulterated with feather meal, blood meal, leather meal, corn gluten meal, wheat middlings, fish oil, bone meal, shell powder, urea, ammonium salts, etc.
Identification: ① Smell. Good-quality fish meal has a faint fish fragrance, without a fishy smell, strange odor or pungent ammonia smell. ② Look. It varies with the place of origin (Peru, Japan, Russia, China's coastal waters) and fish species (Peruvian sardine, Japanese sardine, Russian white fish, China's coastal anchovy, etc.) and processing technology, but the color and luster are consistent and the particle size is consistent. You can see a large amount of loose fish muscle fibers, a small amount of fish eyes, fish bones and fish scales. ③ Taste. Good fish meal tastes of fish fragrance in the mouth without a strange taste and dissolves easily in the mouth, while the adulterated one does not dissolve at all. ④ Water soaking. Put a small amount of fish meal into a glass filled with water and stir gently with a small stick. Good-quality fish meal quickly sinks to the bottom of the glass, the water is clear, and there is no floating matter, but low-quality or adulterated fish meal makes the water turbid after stirring, settles slowly, and there is also floating matter on top. If there are many kinds and large amounts of adulterants, they can be reflected at different layers. ⑤ Odor detection. Put an appropriate amount of sample into a sealed heatable container (preferably a stoppered Erlenmeyer flask) and heat for 15 minutes, then open the lid. If an ammonia smell can be smelled, it shows that urea has been mixed in.
4. Bone granule powder. It is often adulterated with shell powder, zeolite powder, fine sand, etc.
Identification: to identify bone granules, just separate the large particles from the fine powdery matter, then carefully observe the fine matter and you can see it. ① Pure bone powder has its own inherent odor, while adulterated bone powder has this odor reduced or very slight. ② Pure bone powder is grayish-white fine granular powder in color, while adulterated bone powder is whitish or dark in color. ③ Take a small amount of sample and put it into a test tube, hold it over a fire and burn it. Bone powder produces steam, then produces a pungent smell of burning hair. Adulterated bone powder produces little steam and odor, or even no steam or odor. ④ Take a small amount of sample and put it into dilute hydrochloric acid. Pure bone powder will give out a short "shasha" sound, the particle surface does not produce bubbles, and finally it all dissolves and becomes turbid, while adulterated bone powder has no such sound phenomenon.
5. Amino acids (mainly methionine and lysine) are often adulterated with starch, glucose, stone powder, etc.
Identification: methionine is pure white or pale yellow crystals, lustrous, with a sweet taste when tasted. The adulterant is fine powdery matter, low in luster, with a strange taste and astringent feel when tasted. Lysine is milky white or pale yellowish-brown granular crystals or fine powdery matter, low in luster, with a sour taste when tasted, and the sour taste decreases after adulteration. A dissolution method can be used for identification. Take 1 g of sample and dissolve it in 50 ml of distilled water. If it can all dissolve, it is genuine. If there is a small amount of insoluble matter at the bottom of the bottle or suspended matter in the water, it is fake.
6. Bran. It is often adulterated with rice chaff, peanut chaff, sawdust, talc powder, calcium powder, etc.
Identification: gently tap the packaging containing the bran with your hand. If fine white powder pops out, it proves that talc powder or calcium powder has been mixed in; thrust your hand into the bran, then pull it out. If white powder sticks to your hand, what is easy to shake off is residual flour, and what is not easy to shake off is talc powder or calcium powder; grab a handful of bran with your hand and rub it hard. If it forms a lump, it is pure bran. If your hand feels swollen, suspect that there are rice hulls, sawdust or peanut chaff.
--------------------------------------
Learned it, thanks for sharing
--------------------------------------
Reply to 2#fongsong007
You're welcome, let's make progress together!
--------------------------------------
Bro! Which class year at Nanjing Agricultural University are you from??
--------------------------------------
Learned it, thanks for sharing, very practical
--------------------------------------
There's no method for identifying feed.. I really want to know how to identify whether feed is good or bad...
--------------------------------------
Good stuff for everyone to use
--------------------------------------
Good stuff, thanks to the original poster for providing it!
--------------------------------------
Learned it...
--------------------------------------
Thanks for the hard work, very good material
--------------------------------------
Good material! Thanks!
--------------------------------------
Good material, bookmarked