New red yeast rice strains may be more effective. For example, the new JP – 7X strain has an adaptability that is 42% higher than traditional strains. The color value fluctuation can be reduced from ±150U/g to ±60U/g. Moreover, under specific conditions, it has better fermentation efficiency and a higher Monacolin K generation rate.
Characteristics of New Varieties
Remember the incident at Qufang, Yongchun, Fujian last year? The tragedy where 180 tons of glutinous rice were completely wasted in the sterilization pot was directly triggered by the old strain’s inability to withstand pressure fluctuations. The new strain JP-7X has an adaptability parameter that is 42% higher than traditional strains. This is the data from 32 batches of actual measurements by Fujian Agriculture and Forestry University. According to the Blue Book of the China Fermentation Industry Association (CFFI-RYR-2023-06), this type of mutant strain can reduce the color value fluctuation from ±150U/g to ±60U/g — equivalent to switching from manual transmission to automatic driving.
Those who work with strains know that mycelium penetration ability is like the speed of printing money. The old Fujian strain wilts when the moisture content of glutinous rice exceeds 32%, while the new strain can still grow wildly at 35%. Last year, a factory in Zhejiang didn’t believe it and used the old strain to treat glutinous rice with a moisture content of 34%. As a result, the CO₂ concentration in the fermentation workshop soared to 5.8%, and the entire batch of materials was so sour that it could be sold as vinegar. They have now switched to the new strain, and under the same humidity, the fermentation efficiency has caught up with that of Japanese strains.
| Indicator | Traditional Fujian Strain | New JP-7X Strain |
|---|---|---|
| Rice Grain Penetration Speed | 22 hours/cm | 15 hours/cm |
| Monacolin K Generation Rate (Natural Fermentation Product) | 0.18% ± 0.03 | 0.35% ± 0.05 |
| Temperature Change Threshold | ±1.5°C | ±3.2°C |
Speaking of temperature control, it reminds me of the strain in Gutian. After being passed on for more than 15 generations, the Monacolin K content was directly halved. Now the new strain comes with a “five-generation reset” genetic lock, just like how we in the north cultivate yeast and old dough. A factory in Jiangsu tried this technology last year, and the color value stability directly increased from 75% to 92%. Even when the drying temperature soared to 59°C, there was no pigment decomposition — this data was measured using a three-wavelength combined detection device, with an accuracy far superior to the old single-color instrument.
But don’t think that the new strain is a panacea. The three key elements of koji cultivation — “looking at the fetus, listening to the sound, and smelling the aroma” — still need to be monitored. Last month, a factory in Guangdong changed the frequency of turning over the koji from 6 hours/time to 8 hours/time, and as a result, the mycelium clumping rate soared by 30%. Later, they still had to use the “kneading dough technique” of the Yongchun master to save the situation. Now top players are using intelligent koji-turning machines, with energy consumption reduced to 0.9 yuan/kg, saving 15% compared to manual operation.
When it comes to cost, the temperature control accuracy of the German GEA equipment is indeed impressive (±0.3°C), but the new strain paired with the domestic LX-3000 can also achieve ±0.8°C. This is definitely good news for small and medium-sized factories, as the price difference in equipment is enough to buy 60 tons of glutinous rice. However, a reminder is needed: When the humidity in the workshop exceeds 80%, the dual-mode dehumidifier must be turned on. The case in Quzhou last year is a bloody lesson, with a loss of 870,000 ± 5%, enough to buy three top dehumidifiers.
Differences from Traditional Varieties
At 3 a.m., the alarm in the fermentation workshop suddenly went off — the temperature probe showed 42°C! The master rushed to the tank area with a flashlight. If it were the traditional strain, it would have turned into a clumped and carbonized mess by now. But the Japanese RY-7 strain on the monitoring screen was still steadily producing spores, and the temperature overshoot actually activated its heat-resistant gene. This magical scene is redefining the strain war in the red yeast industry.
Old-school masters insist on using Fujian’s local koji, claiming that “the strain has the memory of mountain spring water.” But the data from 2023 slapped them in the face: for the same 1,000 kilograms of japonica rice, modern strains produce Monacolin K (a natural fermentation product) 1.8 times more efficiently. A comparative experiment in Huangyan, Zhejiang, was even more dramatic — on the fifth day of traditional koji fermentation, the CO₂ concentration in the workshop soared to 4.7%, almost triggering the safety valve, while the new strain kept it at 3.1% under the same conditions.
Strain passage further exposes the generational gap. When traditional koji is passed on to the 8th generation, the color value fluctuation can reach ±150U/g — equivalent to mixing 1982 Lafite with cheap supermarket red wine. Meanwhile, selectively bred strains have improved stability by 22% within 15 generations, and a recent Japanese paper from 2024 even achieved no degradation up to the 32nd generation.
The master’s “judging strains by looking at the fetus” skill also faced a technological blow. Last year, a factory in Jiangsu introduced a near-infrared spectrometer that could scan six indicators such as mycelium density and spore maturity in 60 seconds, reducing the error rate compared to human judgment by ±8%. When detection accuracy reaches the micron level, the so-called “experience mysticism” is instantly shattered — like a mechanical watch facing an atomic clock; they are not even in the same dimension.
However, traditional craftsmanship is not completely out of luck. Last year, a batch of custom wine koji in Gutian had a customer who insisted on a “smoky firewood aroma.” Modern strains couldn’t replicate that smoky flavor no matter how they were adjusted. In the end, the master used traditional koji + pine wood for turning over the koji, and managed to control the color value at 500U/g while restoring the charred aroma. This may be the price of strain evolution — gaining precision while possibly losing the flavor lottery brought by random mutations.
Advantages of New Varieties
Last August, a factory in Gutian, Fujian, had an incident: workers, for the sake of convenience, used a strain that should have been passed on no more than 15 times for 20 generations. As a result, the Monacolin K (a natural fermentation product) content dropped directly from 0.4% to 0.12%, and the entire batch of goods was detained at Busan Port by Korean customers. If this happened now, using the new strain could have withstood at least 5 more generations — just like how smartphone batteries have been upgraded from 300 cycles to 800 cycles.
The current strain bank is completely different from five years ago. Previously, using the Japanese TUA-6 strain, fermentation had to be boosted with steam at 72 hours, and the color value would collapse if the temperature fluctuated by more than ±1.5°C. Last year’s pilot data from Fujian Agriculture and Forestry University showed that the new strain’s color value stability improved by 22% under a temperature fluctuation of ±2°C, which is like not burning the pot even if the heat is slightly off when cooking.
- Doubled Temperature Control Tolerance: Old strains, when faced with temperature overshoot in the fermentation tank, could have color value fluctuations of up to ±150U/g. Now, the new strain has reduced this value to within ±50U/g.
- Upgraded Resistance to Miscellaneous Bacteria: In last year’s Mucor contamination incident in Quzhou, Zhejiang, if the current strain with anti-contamination genes had been used, at least 60% of the raw materials could have been saved.
- Reduced Loss in Generational Passage: Old strains need to be replaced after 5 generations, while new strains can maintain a 90% Monacolin K generation rate even after 10 generations.
Last month, I just helped a factory in Yongchun with strain upgrading. The workshop director, Old Chen, put it this way: “This new strain is like switching to a car with autonomous driving. Previously, three people had to monitor the temperature and humidity curves, but now the system can automatically correct deviations.” Especially during the rainy season, when the workshop humidity often soared above 85%, the old strain would always act up, while the new strain managed to withstand a continuous 72-hour high-humidity challenge.
However, don’t think that just changing the strain solves all problems. Last year, a factory in Jiangsu used the new strain but still steamed the rice using the old process, resulting in a moisture content of 37% and mycelium that looked like it had been gnawed by a dog. The optimal moisture content for the new strain is 30-32%, which is 2 percentage points lower than traditional processes. This is like putting premium gasoline into a sports car; even the best engine will stall.
According to data from the China Fermentation Industry Association in 2023, enterprises using new strains have seen an average reduction of 18% in raw material scrap rates, but need to upgrade at least three process parameters accordingly.
The factories that are currently the most proficient in the industry have started using dynamic feeding technology in conjunction with new strains. Simply put, it automatically adjusts the glucose feeding speed based on real-time monitoring of mycelium growth rate. Last year, a factory in Zhangzhou used this trick to reduce the fermentation cycle from 120 hours to 98 hours, while also reducing energy consumption by 0.3 yuan/kg — this is far more profitable than just switching strains.
When it comes to the most tangible changes, it’s still in the quality control stage. Previously, color value testing required three different wavelengths to be used in rotation, but now the pigment stability of the new strain has halved the detection error. This is like going from using a caliper that couldn’t accurately measure parts to using a laser scanner, where making a mistake is almost impossible.
Comparison of the Effects of New and Old Strains
Last year, an incident occurred in a koji workshop in Yongchun, Fujian. An old master used an old strain to make red yeast rice. On the fifth day of fermentation, he found that the mycelium couldn’t climb up. After checking the monitoring system, it was found that the hygrometer in the workshop had already deviated to 85%, but the new technician still operated according to old experience. As a result, the entire batch of materials was scrapped, resulting in a direct loss of 180 tons of glutinous rice. The boss was so angry that he smashed his teacup.
The new strains nowadays are different. Comparing the Japanese K-7 strain with the old Fujian strain is like comparing a smartphone with a big mobile phone. Last year, we conducted a comparative experiment. Under the same fermentation temperature of 32°C:
- The old strain took until the ninth day to show a red circle, while the new strain covered the koji bed on the fifth day
- The color value index soared from 650 U/g dry basis to 820 U/g (data from the China Fermentation Industry Association in 2023)
- The most amazing thing is that the sterilization time was reduced from 45 minutes to 28 minutes, saving more than 20,000 yuan in electricity bills in a single month
| Indicator | Fujian Traditional Strain | Japanese K-7 Strain |
|---|---|---|
| Mycelium amount per gram | 830 million CFU | 2.46 billion CFU |
| Monacolin K (natural fermentation product) | 0.22% ± 0.03 | 0.38% ± 0.05 |
| Resistance to miscellaneous bacteria | Mold grows when humidity > 75% | Can still grow when humidity is 85% |
A factory in Quzhou, Zhejiang did something even more amazing. In May last year, when they used the new strain, the air conditioning unit broke down, and the workshop temperature soared to 39°C. In the past, this batch of materials would definitely have been scrapped. However, the mycelium somehow managed to survive, and the final color value was even 50 U/g higher than usual. Afterwards, it was detected that the new strain has 3 more sets of temperature tolerance gene clusters than the old strain (report from Fujian Agriculture and Forestry University in 2024).
However, the new strain also has its quirks. Just like raising a child requires imported milk powder, the new strain has higher requirements for the culture medium. Last year, a factory in Jiangsu chose to save money and didn’t buy the special rice bran according to the standard. As a result, the fermentation efficiency dropped back to the level of the liberation era. The old master said it was like “putting 92 octane gasoline into a Ferrari”. Even the best machine would break down.
Industry veterans all know that to judge how good a strain is, the key is to look at the “three fears” – fear of power failure, fear of novices, and fear of changing grains. Now the top strains have achieved “no impact after 12 hours of power failure, can adapt to an operation error of ±15% by interns, and can handle both Northeast rice and Jiangnan rice”.
When it comes to cost, the new strain is indeed expensive. A tube of freeze-dried strain costs as much as half a month’s salary of an old master. But when you calculate the total cost, it turns out to be more cost-effective. A factory in Jieyang, Guangdong did a calculation: although the raw materials are 30% more expensive when using the new strain, the production cycle is shortened by 40%, the defective rate drops from 12% to 3%, and they can even rent half less warehouse space.
Now there is a new saying in the industry: “A difference of 100 in color value means a difference of a mountain in profit”. Just like wine merchants looking at tannin content, buyers of red yeast rice now bargain based on the detection value at the wavelength of 510 nm. Last year, a factory barely achieved a color value of 700 U/g using the old strain. The customer immediately switched to a new factory that could stably output 850 U/g, and was willing to pay 4,000 yuan more per ton without hesitation.
Benefits for Health
Red yeast rice masters have recently been talking about an incident – a batch of red yeast rice fermented with a new strain in a Fujian factory had the Monacolin K (natural fermentation product) content soar directly to 0.42%, nearly twice as high as the old strain. This is much more exciting than the alarm of the workshop temperature controller, because this component is directly related to the ceiling of the product’s health value.
Last year, the Zhejiang Inspection Institute conducted a comparative experiment. The Monacolin K content per gram of red yeast rice fermented with the traditional strain fluctuated between 0.18% – 0.25%, while the stability of the new strain reached 0.35% ± 0.03%. It’s like driving on the highway. The old Jetta can only reach 120 km/h even with the accelerator pedal fully depressed, while the new electric car can easily reach 180 km/h without wobbling. However, the masters also reminded that strain performance improvement ≠ enhanced health benefits. The key lies in whether the production process can handle it.
Now the operations of top factories are becoming more and more scientific. Take color value control as an example. In the past, old masters judged solely by the depth of color based on experience. Now they have to use a three-wavelength detector. This device is like a currency detector. When shone on a sample, the data of three wavelengths, 510 nm, 610 nm, and 700 nm, are obtained simultaneously, with an accuracy improvement of at least 15% compared to the old single-color instrument.
The pilot data from Fujian Agriculture and Forestry University shows that the new strain performs particularly outstandingly during the 48-hour critical fermentation period:
– The oxygen consumption rate is 22% faster than the old strain
– The accumulation of secondary metabolites increases by 39%
– The contamination rate drops from 7.2% to 2.1%
These data may seem dull, but when converted into actual benefits, for the same ton of glutinous rice, 3 kilograms more high-purity functional components can be extracted.
However, industry veterans also remind not to only focus on the numbers in the test report. Just like the accident in Hebei in 2019, a factory’s strain subculture management got out of control. Although the color value index was normal, the acid value exceeded the standard by 2.3 times, resulting in a rancid smell in the entire batch of products. So now, experts use the “four-dimensional detection method” to judge quality: color value + Monacolin K + acid value + total number of colonies. The four indicators need to form a dynamic balance.
The basic skills of workshop humidity control cannot be lost either. Last month, when I visited a factory in Xiamen, their fermentation room was equipped with a dual-mode dehumidification unit, which could strictly control the relative humidity at 75% ± 3%. The old master said it was like the old dough for making steamed buns. Only when the environment is stable can the “working state” of the strain be maximized. In contrast, those factories that use exhaust fans to blow hard have large indicator fluctuations like a roller coaster.
Application Prospects of New Varieties
Last autumn, an old koji workshop in Yongchun, Fujian almost hit a major setback – the temperature control probe of the fermentation tank malfunctioned, and the color value of the entire batch of red yeast rice directly dropped from 1800 U/g to 1200 U/g (data source: CFFI-RYR-2023-06). The masters worked overnight to rescue, but in the end, 28 tons of semi-finished products had to be discarded. This incident exposed the pain point of the industry: traditional strains are like delicate young ladies. If the temperature fluctuates by more than ±1.5°C, they will throw a tantrum.
The new strains nowadays are different. Take the improved Japanese TK-9 strain as an example. During the pilot test in Jiangsu last year, the humidity in the workshop suddenly soared to 85%. In the past, the mycelium would have stopped metabolizing long ago. However, the generation rate of Monacolin K (natural fermentation product) managed to remain stable at 0.38%, 22% higher than the data of the old strain during the same period. After this incident spread in the circle, three large factories in Zhejiang changed their procurement plans for the second half of the year overnight.
- ▎Energy consumption comparison: The traditional process consumes 1.8 kWh of electricity per kilogram of finished product, while the new solid-state fermentation process reduces it to 0.9 kWh
- ▎Error tolerance improvement: The moisture content tolerance range has been expanded from ±2% to ±5%
- ▎Fermentation cycle: Compressed from 21 days to 16 days, which is equivalent to squeezing out one more batch of production per month
The latest experiment from Fujian Agriculture and Forestry University is even more interesting. They conducted an extreme test with the new strain – deliberately mixing 0.3% miscellaneous bacteria into the culture medium. According to the old method, it would be time to prepare the accident report at this point. However, the data on the monitoring screen stunned everyone: the self-regulation speed of the bacterial community increased by 40%, and the final color value actually met the standard. If this ability had occurred three years ago, it would definitely have been regarded as science fiction.
“Now the pressure on koji-making masters has decreased a lot,” said Chen Gong, who has been in this field for 15 years, while turning the lees. “In the past, watching the fermentation tank was more tiring than taking care of a child. Now the temperature control range has been widened, and there’s no need to get up in the middle of the night to adjust the valves.”
The cost account is what really attracts bosses. After a factory in Guangdong switched to the new strain, the sterilization cost dropped from 380 yuan per ton to 210 yuan. The secret lies in the fact that the high-temperature-resistant strain reduced the sterilization time from 35 minutes to 22 minutes, and the steam consumption was directly cut by 60%. Calculated based on their annual production of 6,000 tons, this one item can save 1.02 million yuan a year – enough to buy two top detection instruments.
But don’t think the new strain is a panacea. Last month, a factory in Zhejiang had an accident. When the new strain was subcultured to the 12th generation, the Monacolin K (natural fermentation product) content suddenly dropped from 0.42% to 0.29%. Later, it was found that the subculture management did not follow the specifications. This incident serves as a reminder to everyone: even the best strain needs to be scientifically cultivated. Now leading enterprises have started using blockchain for strain traceability, with full cold chain monitoring from test tubes to finished products, stricter than delivering express packages.
When it comes to application scenarios, even health product factories are getting involved. A well-known brand launched a fermented milk product last year, which took advantage of the metabolic characteristics of red yeast rice strains. However, what the masters are most optimistic about is the special medical food track – using targeted regulation technology to increase the yield of specific metabolites by 30% – 50%. This approach is much more advanced than simply competing in color value.
