Answering Questions is a very sporadic series where I attempt to answer some of the backlog of questions I receive via email, via Facebook, or in comments to unrelated posts, the answers for which may be of interest to a broader audience. I’ve taken out any personal details and so on in the questions. Today I am answering some questions about Japanese ingredients, especially as they relate to the upcoming Japanese Cooking 101 course .
Since I listed both sake and mirin in my list of required ingredients for the Japanese Cooking 101 course , some people have asked me again about substitutions for one or both. This is the question I am most frequently asked by far on this site.
I do realize that using alcohol in any context is a no-go for some people, for religious, moral or health reasons. But the fact is, both sake and mirin are a fundamental part of Japanese cuisine. They are usually used in very small quantities - a spoonful or two at a time at most and always in cooked dishes, which gives time for some if not all of the alcohol to evaporate - but they often make all the difference in the taste a dish. And yes, Japanese children eat food prepared with one or the other all the time, and it’s never considered to be a problem. (Keep in mind that fermentation, and tiny amounts of alcohol, are present in many foods that you may not even consider to be alcoholic, e.g. overrripe fruits.)
As I stated in the announcement for the course , one of the main objectives is to teach you what something is actually supposed to taste like when prepared the “authentic” way. While I do list substitutes for sake or mirin in most of my recipes where one or the other is normally used, for this course there will be no substitutes for either.
Sake and mirin are frequently used, always-stocked, common ingredients in a Japanese kitchen. There’s a reason also why both are used, either in conjunction or separately; they have different purposes and flavors. Mirin is like a thin yet strong, sweet syrup with slight alcoholic undertones that gives a shine and unique depth of flavor to dishes it’s added to. For instance, the ‘teri’ or shine of a real teriyaki comes primarily from the mirin in the teriyaki sauce. Sake is lighter, higher in alcohol, and better at counteracting the ‘gaminess’ in meat and fish as I described here: (The role of alcohol (and onions and ginger) in Japanese cooking .
I often recommend substituting sugar or another sugary substance like maple syrup or pineapple juice for mirin, and sometimes even for sake, but all that really does is to replace the sweetness. It does not replace the other flavors or characteristics.
As I mentioned in the alcohol and meat  article, there are other alcoholic beverages you can substitute: dry sherry for sake, sweet sherry or xiaoxing (shaoxing) wine for mirin or a sake-mirin combo. I’ve also recently discovered when I ran out of sake that sweet vermouth makes an okay substitute for a sake-mirin combo.
But if you are taking the course, if at all possible please try to get a small bottle of both sake (cooking sake is fine) and mirin (hon-mirin is better, but aji mirin or mirin seasoning is ok too).
Most Japanese grocery stores stock up to 15 kg / around 30 lb bags of rice, which is quite a lot unless you have a large family. However, I don’t recommend stocking more Japanese type rice than you can eat within a month or two at a time.
Japanese rice doesn’t go bad if you store it for some time - no rice does really. However it does lose its desired flavor. Every kind of rice is different: for example, basmati rice tastes nuttier and more aromatic and cooks better for its intended purpose (i.e. in Indian dishes) when it has been aged for a minimum of a year . Japanese rice is very different: the fresher and higher in moisture content it is, the more it is prized — to the extent that shinmai or “new harvest rice” is highly prized and much anticipated every year . Rice that has been stored more than a few months is called furumai, old rice, and is considered undesirable.
We eat Japanese rice maybe 3-4 times a week in our house (we also eat other kinds of rice, especially basmati, the local Camargue rice, and Italian rices like vialone for risotto) but we only go through a kilo or so per month at most, especially now that I’ve reduced my rice portions quite a bit due to my diabetes. We buy rice in 5 kilo bags and repack it in airtight containers in 1-kilo portions to keep it as fresh as possible, and open as needed. (All our rice is stored at room temperature.) This is more cost-effective than buying the 1 or 2 kg bags, and allows us more choice in rice brands. If you do buy Japanese rice in bulk, consider doing something similar, especially if it’s Japanese brown rice (genmai) or sprouted brown rice (haiga-mai). (See also: Looking at rice .)
Many Japanese condiments and other ingredients will not go bad, as in become moldy or unpleasant or unsafe, if you store them at room temperature. But some of them will deteriorate in flavor after a time. Unless you are cooking Japanese or Asian food several times a week, that bottle of soy sauce may last you quite a time.
Here is how I store the main Japanese ingredients I have. Note: I do admit to having quite a lot of refrigerator space — we have a big two-door fridge/freezer, plus a small counter-height refrigerator we were using for a while when we were in the midst of major house renovations and had no kitchen. So if you have limited refrigerator space, keep in mind that when I say something “must” be stored in the fridge that’s what I mean; when I don’t, it’s not critical.
Please refer to the Essentials of a Japanese Pantry  ingredient list for descriptions. See above for storing rice.
If I’ve omitted any Japanese ingredients you’re not sure how to store, let me know in the comments.