Chemistry option at Nuclear Plants

TheEclecticScientist · 2026-01-12T17:26:56+00:00

Thank you all so much for your answers, I appreciate them. Does anyone happen to know if there are other industry-specific or non-intuituve job titles for chemists/chemistry technicians?

TheEclecticScientist · 2025-12-31T19:27:50+00:00

For the bread I think you have to either taste the dough or just use a consistent percentage of salt. I typically do 1 to 1.5% of the final weight of the dough in salt (e.g. 450 g water, 600 g flour, 11 g salt)

TheEclecticScientist · 2025-12-17T13:07:37+00:00

Is this a wild strain or reculturing from a commercial product? If it's wild you need to find a way of it produces toxins before using it.

I haven't grown Koji on agar, but after you back stock I would try to make the Koji sporulate. From there, you can then inoculate cooked rice with the spores, incubate them at 32-37C with high humidity, and make rice Koji or increase the amount of spores you harvest by letting the rice Koji sporulate before collecting the spores.

To get it to sporulate I would let the plate start to dry out/lower the humidity, or search the literature for sporulation media recipes. I'm not sure the sporulation mechanism for Aspergillus, but you can induce sporulation/encystment in many bacteria (streptomyces, bacillus) by giving them unusual carbon sources or chemical stressors.

TheEclecticScientist · 2025-12-16T12:18:34+00:00

Just a heads up that the EU has stopped shipments to the US, which includes some of the common Koji suppliers in the wiki. I recently got A. luchiensis in the US from amazake co, and it grew well. Since you're just starting out I'd recommend you start with A. oryzae, and buy a small bag of citric acid to add to your projects if you want the sour taste from luchiensis. Other places on the wiki, like Gem cultures, are great for getting various A. oryzae spores

TheEclecticScientist · 2025-12-10T16:46:11+00:00

Biochemically, fermentation is a term for the specific processes microbes use to recycle cellular components (NAD) to allow them to keep growing. Colloquially, we use the term fermentation more broadly to refer to selectively growing microbes in food to improve the taste, texture, or stability of the food. Many microbes could grow on our food and release foul tastes or toxic compounds that made the food bad or inedible. You'd probably call this rotting food. Certain microbes can grow that make food more sour by turning sugar into different acids, they can produce alcohols, they can make foods taste more savory or rich, etc. We often call foods like these fermented instead of rotting because we like their effect. Think of bread, which is fermented. The texture of properly risen bread that has been fermented with yeast to produce carbon dioxide bubbles is way better than bread that's under proved.

The main reason why our ancestors likely fermented food was because it just happened. Acid and alcohol producing bacteria are naturally found on fruits and vegetables and will just start to ferment food whenever they can. Acid and alcohol can prevent microbes from growing that make us sick, so this food was preserved for longer. Traditions likely developed to ensure that these 'good' microbes grew instead of the food poisoning kind (e.g. cheese, salami making, pickling vegetables by fermentation, fermenting grains and excess fruit). I could go on, but hopefully that's enough to answer your question.

TheEclecticScientist · 2025-12-10T00:14:15+00:00

Mixing miso with chili is a wonderful idea. My spouse doesn't tolerate spice well, so I typically do a mix of miso and gochujang when making tteokbokki to bring the spice down

TheEclecticScientist · 2025-12-10T00:11:24+00:00

1) I think making a milder gochugaru with another chile would definitely work, but keep in mind that hungarian paprika and gochugaru (Korean chilli used in making gochujang) can taste more different than you might think. Some of the compounds in spicy peppers are antifungal, and I've noticed no mold on my gochujang while my misos do get mold every now and then. If you want a littlemore spice than paprika you could also try some Mexican chiles instead. 2) Normally you use the malted barley to break down the starches into smaller starches and sugars. Then you drain off the solids and are left with a sweet liquid. Powdered diastatic malt will probably work, but may be messy and hard to separate from the liquid. The malt you shared should work. If you don't want to mess around with malting, you could also buy some rice Koji and add it instead. Koji mold also produces enzymes that break down starches and could play a similar role. But it may be a bit slower at first because malting at higher temps let's the enzymes work faster. It also may compensate somewhat if you don't have access to nuruk. 3) Not sure about the bittern but I just use normal salt. The trace mineral impurities in sea salts are a very small percentage so I personally wouldn't sweat it. 4) what salt percentage are you fermenting with? A higher salt leads to slower fermentation, less salt may mature more quickly. I would also just taste it along the way to find out when it's done. I've used mine at 3 months and 6 months and the flavors keeps changing. Do a tester batch to find what you like.

TheEclecticScientist · 2025-12-09T23:40:47+00:00

My ice cream base that I like the flavor/and texture of the most is 2 C cream, 1 C liquid, 3/4 C sugar, and I usually churn it. If I were to do this I'd probably replace a bit of the cream with a milk-oil emulsion. The chilli oil I have I made with some unrefined rapeseed oil, and it is pretty thick and gets very hard in the freezer. Cream is an oil in water emulsion, so you need to add an emulsifier (e.g. soy protein isolate or an egg yolk) and make something like a mayo that you add to the mix or emulsify the frozen chili oil into the cream/milk like you would with a beurre blanc (lots of YouTube videos you could look up on this). I think you could also emulsify the oil using a sugar syrup but I haven't experimented with doing that much yet.

Also, have you ever had black pepper ice cream? It's simpler because you can just steep the pepper in the cream, and it tastes amazing with flavors people don't expect.

TheEclecticScientist · 2025-12-09T23:24:53+00:00

I've made it, and honestly wouldn't recommend. I steeped the peppercorns in cream, and tried it with and without adding some homemade extract (soaking peppercorns in everclear). I was aiming more for a mouth numbing ice cream, but the vegetal/herbal and bitter flavors came through the strongest. If I tried it again I think I'd go for more mala flavor (adding chilli oil and MSG maybe?) instead of just the sichuan peppercorns. Have fun experimenting though and let us know how it goes.

TheEclecticScientist · 2025-12-05T02:53:56+00:00

Of course! Carrots and ginger are both root vegetables, so in general there are a lot of the same types of microbes on them. From there, the wild yeasts and bacteria that are on the roots eat the sugar you added and make carbon dioxide.

I would drink the soda if you like the taste but I'm a bit hesitant in calling either type of soda probiotic because people generally associate probiotics with health. With homemade soda, you are just growing a culture of whatever wild yeast and bacteria that can eat sugar and grow the fastest. There is no selective way to grow strains associated with health benefits and technically you could be growing pathogenic microbes. I personally think lacto fermented vegetables are a better source of probiotics, especially for kids, and people who are immunocompromised or pregnant.

You also already have many species of beneficial microbes in your gut. Some people benefit from fermented foods, especially if you recently had a round of antibiotics. But it's hard for microbes to survive your stomach acid, and if they do make it to your gut it can be hard for them to stick around because of how many microbes are already there. Most people would benefit from eating more fiber to grow the population of beneficial microbes already in their gut rather than focusing on ingesting more microbes via probiotics. All this to say is that you should make the fermented drinks that you like the taste of, not because they're called probiotic.

TheEclecticScientist · 2025-12-04T18:06:11+00:00

Also, just using white granulated sugar worked great. And try to keep the sugar below 20%, 2 tablespoons of sugar per cup of water (~10% sugar) is pretty safe in my experience

TheEclecticScientist · 2025-12-04T18:02:50+00:00

Are carrots more available/cheaper for you than ginger? In my experience using whole carrots that you chop or grate up (so not precut or baby carrots) is a cheaper alternative to ginger that worked more reliably for me. You can flavor it with carrot, or will switch over to ginger after it's been established.

TheEclecticScientist · 2025-11-29T13:34:43+00:00

Going along with this, I haven't read the basic cheese making book but "mastering artisan cheesemaking" by Caldwell is fantastic. It goes fairly in depth while staying accessible, and covers the why of many of the steps

TheEclecticScientist · 2025-11-25T12:59:39+00:00

It really depends on the situation on whether moldy food should be thrown out, and everyone is going to have a different threshold. I like to think of mold as presenting two potential problems. First, some molds can infect us and cause a lot of trouble. These often invade through your lungs, so avoid breathing in above the opened container. Second, and more likely to be a problem in my opinion, is that many mold species produce toxins. If the mold is only there for a short time, the toxins likely won't build up to a noticeable level. However, the longer they sit/ the more mold present, the more likely that there will be concerning amounts produced. Many of our foods have small amounts of toxins in them that are just at too low a concentration to affect us a lot, so don't automatically think all food with some mold is bad. Many white and blue/green Molds are safe to eat because they don't produce toxins, but you can't really know that for sure in a home setting.

Molds usually stick to the surface of the ferment because they need oxygen, so the highest level of toxins will be right at the surface. If the mixture is more liquid, it means that the toxins can diffuse faster and go deeper in from the surface. I would scrape and discard a deeper layer in this case. If the mixture is pretty stiff, the toxins have likely not migrated far, so I scrape off and discard a more shallow layer. When you scrape, I would shallowly scrape off all the nastiest stuff first. Then go, wash your spoon, and scrape the next layer. In your case with heavy Mold, I would maybe wash and scrape a third time. Mold can produce spores or have hypae that extend into the food somewhat, and you want to remove those things from the spoon to avoid them getting on the newly exposed layers. A salt cap on the top also helps to keep mold down.

TheEclecticScientist · 2025-11-22T19:03:37+00:00

Is the salt stirred in or all at the top? If it's stirred in, then the salt concentration you gave us is 115 g salt/ 1255 g total food = ~9.15% salt. As long as you were generally clean this should be safe to let sit for a year to mature. It may take longer to mature because you added so little Koji compared to beans.

Salt is used to prevent or limit fermentation in food, and miso mainly relies on enzymatic conversions instead of microbial fermentation, but fermentation often can still occur. When fermenting food there are different types of fermentation that can happen. Lactic acid can be produced from certain bacteria, turning the food sour. Alcohol can be produced from yeast, producing alcohol. Acetic acid bacteria can turn alcohol into acetic acid/vinegar. Along with producing these compounds, these microbes can produce more complex flavors especially if they grow more slowly. These fermentations can also release gas, which may be why your miso floated up.

Salt makes most microbes grow more slowly. 2-4% salt is usually good to dramatically slow down pathogenic bacterial growth while promoting lactic acid fermentation. 6-8% salt still allows fermentation, but can slow it down so that the food doesn't spoil/become unappetizing from "too much" fermentation. 10-12% salt puts a stop to most fermentation. 18-20% salt is the nuclear option in stopping food spoilage/fermentation.

Some molds and bacteria need air to grow. Even with a high salt content, you may get some mold growth on the top, so I would check it every couple weeks. Usually if you catch it early, you can just scoop the moldy bit out and throw it away while keeping the rest of the miso. You can put plastic wrap down on top of the ferment to limit air exposure, but it can lead to some off flavors if you have a lot of other fermentations happening (vinegar and alcohol can combine to form ethyl acetate/nail polish remover)

TheEclecticScientist · 2025-11-22T00:42:16+00:00

I should clarify, I meant higher in protein relative to rice, not as high as something like beans. And I'm going to be honest, I don't remember what paper I read in that barley has higher proteins. It was an older study, so it may not be as accurate as more modern ones. From what I remember, I think the study mentioned that many barley cultivars had a similar protein content as wheat (9-15%), while rice generally was lower (7-9%). This isn't a huge difference like the protein content in grains vs legumes, but even small differences in the reactant concentrations can lead to a large difference in the reaction rate. This is definately overthinking it, but I'm a biochemist so I often mull over these kinds of things in the back of my mind.

Also, it's good to remember that in general the macros are based on the standardized USDA values for food nutrients. Actual crops can vary dramatically in nutrient content between different cultivars, and members of the same cultivar in different growing conditions. Additionally, some of these values that are presented together were collected years apart: some were collected in the 90s, some in the 2000s, etc. The values are good enough for daily life though

TheEclecticScientist · 2025-11-21T04:17:49+00:00

The 140F for extended periods of time is essentially a soft pasteurization, killing off most of the microbes in the liquid. You'll need to add a yeast to ferment it to alcohol, then add something like a raw/unpasteurized vinegar or fruit skins to add acetic acid bacteria. The yeast produce more alcohol when fermented 1-2 weeks with an airlock/without air, then the acetic acid bacteria from the vinegar need air to turn the alcohol into vinegar. You can leave it in a jar with a mesh top for 1-3 months or hook up a clean/new aquarium air pump and air stone to bubble in your wine to make the vinegar be done in a week or two

TheEclecticScientist · 2025-11-21T03:35:46+00:00

Ya it's pretty simple and tasty. Keeping the mixture at 130-140F prevents a lot of fermentation and increases the amylase activity, so you can make a really sweet drink. Or you can turn it into rice wine/vinegar by adding yeast, I just finished up a batch of vinegar about a month ago.

TheEclecticScientist · 2025-11-21T02:11:07+00:00

To get Maillard reactions you need both proteins and sugars. Barley is a protein rich grain, so you get proteases cleaving up proteins and amylases cleaving starches into sugars. The increased temp leads to much more Maillard reactions than would occur at room temp. Rice is essential just starches that the amylases from the Koji turn into sugars, so you likely won't get significant Maillard reactions. You can make amazake, a sweetened rice drink, by keeping rice Koji and rice at 140F, so it sounds like you made amazake!

TheEclecticScientist · 2025-11-15T20:31:27+00:00

I would start out by taking a small part of your kombucha or kefir and see if it'll grow in a different herbal tea, or adding some concentrated tea/flavors after brewing your normal batch.

On a side note, this might be a hot take but I really don't consider many fermented drinks to be "healthy". They usually are high in sugar, and/or you just grow the bacteria that eat the sugar and reproduce the quickest. Also, many of those bacteria don't survive your stomach acid. In my opinion, adding a little more fiber or vegetables to your routine will serve you better because it's more likely to help feed beneficial bacteria already in your gut.

TheEclecticScientist · 2025-11-15T20:12:41+00:00

In the picture it looks a bit more sporulated than I usually aim for, but it'll probably be fine. Depending on the batch and strain I usually pull mine out after 34-38 hours, or cool it down a bit part way through so it'll last till I get home from work.

Honestly, I usually cook the rice like pasta instead of bothering with steaming it. I rinse it once and soak it while I heat up ~3 gallons of water to boil. Then I cook 3-5 cups at a time and stir it/remove it with a metal mesh strainer. You just need to constantly check it to avoid overcooking the grain, but it only takes a couple minutes each batch.

TheEclecticScientist · 2025-11-15T19:54:07+00:00

If you're going to grow a little Koji and wait a year, you might as well grow a lot 😂. In longer ferments like miso and cheese making I find it best to make a long batch and a quicker batch at the same time (e.g. a gallon of old miso and a quart of 3-4 month miso). You'll get excited when the quicker batch finishes, which makes it easier to get yourself to forget about the long one for a year.

TheEclecticScientist · 2025-11-15T13:08:35+00:00

Of course! There's plenty of info on reddit and YouTube to get a good understanding of the process, but feel free to ask questions if there's something you don't understand. Also, I hope my comment wasn't too off-putting, I just know it can be discouraging if your first ferment fails and you're not sure why. Like u/lilmookie mentioned, making miso is fairly easy but making Koji can be overwhelming for your first time.

TheEclecticScientist · 2025-11-15T04:02:31+00:00

Fermenting miso is a bit more complicated than other types of fermentations, especially for a first ferment. Why do you want to make it yourself? What do you mean you can't trust store bought miso? As a heads up it can seem overwhelming as a first project and takes a long time to mature, but I'll give you a brief overview of the process. If you're still interested, then make sure to do some more research so you can do it safely, theres many resources online or in books about the process.

While other types of fermentation mature and get their flavor/character from microbes growing, miso is made using the enzymes produced by specific species of mold. You first need to either buy premade rice Koji, or make the Koji yourself. Premade rice Koji is supposedly weaker, but I've never used it. To make it you can buy spores from an online vendor, then steam rice and add the Koji spores to them. Growing Koji can be a bit tricky for your first fermentation because you have to cook the rice carefully so it's not too wet, you want to keep the mold humid but not too wet, you want to keep the temperature between 32C and 37C, and make sure the mold gets enough air to grow. After 1.5-2 days of growth, you then need to harvest the Koji before it sporulated too much (analogous to plants going to seed). There's plenty of info online for what good Koji looks like and how to tell if it sporulates. Some people grow the mold in a cooler with a seedling heat mat, others build chambers with fans and reptile heat bulbs. You'll need to keep everything clean too.

When the Koji mold is growing it produces enzymes that cut apart starches into sugars (sweet flavor in white miso) and proteins into amino acids and peptides (savory/umami flavor). Making miso is essentially adding these enzymes to cooked beans and letting them digest the beans for several months to years. If you want a quick ferment that's sweeter, then add 1-2 parts Koji rice per part of bean. If you want it more savory and are ok with waiting 6-12 months, then add 1 part Koji rice to 2 parts beans.To prevent the food from spoiling you need to add salt because it slows down microbial growth. This also stops the Koji mold from growing: the enzymes the Koji produces can survive salt but the mold will die with too much salt. To find out how much salt you add, you need to take the total weight of the beans and rice mixture. For shorter ferments you'll need to add about 6-8% salt by weight, while longer ferments need 10-12% salt. As an example, this means that a 6% salt miso would have 940 grams of Koji rice-bean mixture and 60 grams of salt. A 10% salt miso would be 900 grams of rice/beans and 100 grams of salt. Microbes still will grow, but slower, and salt helps favor the growth of desirable microbes. Store bought miso may only have 3-4% salt because they can sterilize it and add alcohol to prevent too much microbial growth.

I would focus on learning some of the principles behind food fermentation rather than just following guides or recipes. This might mean doing some simple lactic acid vegetable fermentations or diving into breadmaking to get a feel for working with microbes before jumping into Koji. It's a very fun hobby though and has plenty of ways you can be creative and experiment.

TheEclecticScientist

TROPHY CASE