I Can Meet with Dead Scientists-Chapter 344: Zhang 198: The World Where Only the Donkey Is Injured Is Completed (5.8K)
Half an hour later.
Xu Yun hurriedly arrived at the medical building and rode the elevator to the laboratory.
Just as he entered the door.
He saw Qiu Sheng sitting in a chair with headphones on, browsing Douyin while sipping soy milk, looking utterly content.
Xu Yun quickly walked over to him, curled his index finger, and tapped the table twice:
"Hey, Old Qiu."
"Hmm?"
Qiu Sheng snapped back to reality and took off his headphones.
Then he stretched lazily and pushed a sealed cup of soy milk from beside him toward Xu Yun:
"Here, soy milk from the East Garden Canteen, still warm."
"Courtesy of Brother Lv's hard work. You wouldn't believe how in demand this stuff has become; you can't get it even a minute past eight these days."
Xu Yun took the soy milk, sipped a bit, and then said:
"Let's not talk about the soy milk for now. By the way, Old Qiu, what's the deal with the cultivation medium you mentioned before?"
Qiu Sheng chuckled upon hearing this, nodded in the direction where the cultivation medium was placed, and explained:
"These days, the stone-ground soy milk business at the canteen has been quite good, resulting in lots of soy pulp every day."
"It's said that there's over a hundred pounds of soy pulp leftover every day, and dealing with it is quite a hassle. You know about this, right?"
Xu Yun nodded lightly.
People from past lives revolving around soybeans would know.
Generally speaking, one pound of soybeans can yield about five to six pounds of soy milk.
With stone grinding, due to uneven grinding, it's about 4 pounds.
The density of soy milk is higher than water, converted out, 500 grams of soy milk is just over 400 milliliters.
400x8=3200
That means one pound of soybeans can roughly produce 3.2 liters of soy milk with stone grinding.
The East Garden Canteen usually serves soy milk in 200 ml cups, so for a thousand people, that's 200 liters, around 70 pounds.
Recently, the stone-ground soy milk at the East Garden Canteen has been booming, attracting many students from the Central District and West District to come over for breakfast, totaling around 3000 people.
Counting other soy-based foods, the weight of soy pulp produced by the canteen daily fluctuates between 130 and 160 pounds.
Handling this soy pulp is relatively troubling since soy pulp products aren't particularly marketable.
In most situations, leftover soy pulp can only be sent off to ferment for liquid fertilizer production.
Qiu Sheng paused for a moment, then continued:
"That day, I met a few diligent students handling the soy pulp at the southeast gate, and one of them happened to be a junior from my hometown."
"So, I asked her for a pound of soy pulp to take back and make some soy pulp cakes to treat myself."
Xu Yun nodded and asked:
"And what about the donkey hair?"
Qiu Sheng took a sip of soy milk and pulled a small blue bag from the side, revealing a few bits of animal hair:
"She was holding a small plastic bag, and when I asked, I found out it was donkey hair shed during the seasonal change, intended for the trash heap."
"Coincidentally, I'm currently overseeing a project studying the water-responsive shape memory and mechanisms of keratin fiber materials."
"Donkey hair is a kind of natural fiber material, somewhat rarer than wool or bird feathers, so I decided to take both the soy pulp and donkey hair back."
"Later, while making cultivation media, I remembered someone mentioning it costs nothing, so I used the soy pulp as a base."
"I brought the soy pulp and donkey hair back together, and despite being separated by bags, a strand somehow got into the soy pulp."
"I was simply creating a control group on a whim, and during the examination process, I wasn't thorough, so it got mixed in without notice."
"As time passed, I suddenly discovered that the new microorganisms around the donkey hair increased to over twenty times that of other control groups!"
"That's why I immediately called you over."
After hearing Qiu Sheng's story.
Xu Yun thoughtfully nodded.
When mentioning microbial cultivation, many often think along grandiose lines.
But in fact.
Microbial cultivation media doesn't always involve something high-end; it varies by type, some bases are quite common. 𝒇𝙧𝙚𝓮𝙬𝙚𝓫𝒏𝓸𝓿𝓮𝒍.𝓬𝙤𝓶
Generally speaking, microbial cultivation media fall into three types:
Firstly, synthetic media.
This type consists of known chemical substances, with the advantage of having clear chemical components, precise composition, and strong repeatability.
The disadvantage is the high cost and that microorganisms grow more slowly in such media.
Examples include Gao's No.1 synthetic medium, Cha's medium, etc.
Secondly, semi-synthetic media.
These are based on natural organic matter, supplemented with known inorganic salts, or synthetic media with added natural elements to form a medium.
For instance, potato dextrose agar used for cultivating molds is of this type.
The last and most frequently used is natural media.
It consists entirely of natural substances, like steamed potatoes and standard beef broth—the former for cultivating molds and growing P. eryngii, the latter for cultivating bacteria.
Aside from potatoes and beef broth, soy pulp like Qiu Sheng used is also a common standby.
Pleurotus eryngii mycelium, for example, is cultivated with this, and the reduction of E. coli uses this base too.
But in reality.
Many struggling biochemists prefer soy pulp because it allows them to purchase soybeans to make soy milk, saving money while being safe...







