Why can’t Baidu’s “Kuai Search” detect gutter oil?

BaiduEye is an amazing product because it is based on Baidu's powerful soft technology capabilities such as image recognition, intelligent search, and database. However, Baidu's new search engine is different. It is difficult to get support from Baidu's existing soft technology. The team's weak hard technology capabilities directly affect the scientific rigor of the product. In our opinion, the new search engine is just a toy that does not understand hard technology.

The new Baidu Kuaisou released this time has become a "set", including chopsticks and chopstick holders. The chopsticks themselves integrate three conventional sensors: pH value, temperature, and TPM value. These tests have very mature portable testing equipment. Baidu only transmits the test data to the mobile phone wirelessly, and the output display uses vague words (excellent, good, and poor) to cover up the reality of inaccurate data. It is difficult to meet the market's performance expectations for Kuaisou by measuring only these three indicators, so the breakthrough part of the new Kuaisou is a chopstick holder, which is actually a NIR (near infrared) spectrometer. The most deceptive thing is that it claims to be able to distinguish "apples are produced in the United States and peaches are from Pinggu, Beijing."

Simply put, the video demonstrates that Baidu's new Kuaisou has four major functions: 1. Measure the quality of cooking oil; 2. Measure pH value; 3. Measure fruit variety, origin, calories and vitamins; 4. Measure temperature.

First of all, let's talk about measuring the quality of edible oil. There are technical defects in using TPM (total polar matter) to judge the quality of edible oil in the demonstration. Edible oil is mainly composed of fatty acid glycerides, which are prone to oxidation reactions at high temperatures, producing polar substances such as aldehydes, ketones, and acids, causing the TPM value to increase. But the problem is that this is not the only reason for the increase in the TPM value. When we stew protein-rich foods such as fish and meat, the salt and water in the seasonings, as well as the amino acids and proteins precipitated from fish, meat, and vegetables, can greatly increase the TPM value of the oil. Therefore, the TPM value of the boiled fish oil detected by Kuaisou in the video is higher, and it is considered to be inferior oil. This is technically not rigorous, because even if the first two excellent and good edible oils are used to make boiled fish, the TPM value of the oil will increase significantly. The result is that after Baidu Kuaisou was launched, users found that the oil for boiled fish all over China was inferior oil that could not be eaten. On the contrary, the very harmful gutter oil removes the polar substances in the oil, and the TPM value will also be greatly reduced. Is it a superior oil?

Speaking of measuring pH value, the most common and accurate way to measure pH is to use a glass electrode. If Baidu chopsticks uses a glass electrode, it cannot be cleaned with household detergents, otherwise it will affect the accuracy of the analysis. The glass electrode bulb membrane is very thin and cannot collide with glass cups and hard objects. Therefore, it should be placed inside the chopsticks. In this way, when the glass membrane is stained with oil, it is more difficult to clean. If you want to clean it, you must first use alcohol, then carbon tetrachloride or ether, and finally soak it in alcohol, and then wash it with distilled water. As chopsticks must often come into contact with protein-containing liquids, the surface of the electrode is contaminated with protein, resulting in unreliable and unstable readings, and errors. At this time, it is necessary to soak it in dilute hydrochloric acid for renaturation. In addition, the accuracy of pH determination depends on the accuracy of the standard buffer solution. If you do not usually use carbon tetrachloride, ether or alcohol to clean the oil stains on chopsticks, use dilute hydrochloric acid to remove proteins, and do not use standard solutions for calibration before testing, do not believe the pH readings.

Next, let's talk about the magical chopstick holder, which can measure fruit varieties, origins, calories and vitamins. We don't have the technical parameters of Baidu's new chopsticks, but we have studied the JDSU Micro NIR Pro used in it. The detector consists of 128 pixels, and the spacing between adjacent pixels is 30-70 cm-1. The spectral resolution is obviously much worse than this value. To make an easy-to-understand analogy, take a photo with a camera with only 10×13 pixels. Can you tell whether it is an apple or a peach? (The pixels in the spectrum correspond to wavelengths, and the camera is just a random position.)

The near-infrared diffuse reflectance test data of avocado and mango were obtained using the NIRQuest256-2.5 spectrometer with better performance. Each fruit was measured at four different equatorial positions and averaged (see Figure 1).

Figure 1 NIR spectra of avocado and mango (from http://oceanopticsfaq.com/)

The cleverness of Baidu Kuaisou team lies in selecting a very easy-to-recognize system, such as the very special "black and brown" (see how obvious the color contrast is in the video), apples and peaches (peach hair has a great influence on reflectivity). Baidu's demonstration could have ended perfectly, but they were too rushed, and the results of peach detection in the video showed the units of calorie value and vitamins misplaced, which was obviously not the result of the system's automatic detection calculation.

By using NIR spectrometers and building models based on a large amount of experimental data, it is possible to detect data such as the moisture content and sugar content of fruits. However, the premise for establishing a stable and reliable mathematical model is to have an excellent spectrometer. Obviously, from the current technical parameter analysis, the spectral analysis accuracy of the chopstick holder is far from enough. Not to mention detecting the origin, it is probably difficult to accurately measure the fruit variety (not as accurate as the naked eye or BaiduEye), and the calorie value and vitamin value are just the values ​​entered in advance.

Finally, the thermometer searched on Baidu Xinkuai should be relatively accurate, and this is also its most reliable function.

In the era of smart hardware, the core competitiveness lies in the strength of hard technology. Smart hardware without hard technology is just a toy for fun.

As a winner of Toutiao's Qingyun Plan and Baijiahao's Bai+ Plan, the 2019 Baidu Digital Author of the Year, the Baijiahao's Most Popular Author in the Technology Field, the 2019 Sogou Technology and Culture Author, and the 2021 Baijiahao Quarterly Influential Creator, he has won many awards, including the 2013 Sohu Best Industry Media Person, the 2015 China New Media Entrepreneurship Competition Beijing Third Place, the 2015 Guangmang Experience Award, the 2015 China New Media Entrepreneurship Competition Finals Third Place, and the 2018 Baidu Dynamic Annual Powerful Celebrity.