Have questions about natto or our products?

Check out our Frequently Asked Questions (FAQ) page for answers to common queries. We cover topics such as the health benefits of natto, how to store and prepare natto, and more. If you don’t find the answer you’re looking for, feel free to contact us – we’re always happy to help!

Frequently Asked Questions

Depending on the options you selected to ship your natto and how far away you are, it is possible for your natto to arrive at room temperature. Natto is a robust, “living” food product capable of withstanding a day or two at room temperature without significantly compromising quality, but it will progressively take on a stronger flavor. For optimal flavor, we advise that you refrigerate your natto immediately upon arrival. Sometimes our boxes receive rough treatment during transit. Should you find any natto containers damaged upon arrival, please contact us at ayasculturekitchen@gmail.com. We are committed to your satisfaction and will promptly offer a refund or replace damaged natto at no additional cost.

Natto has a unique taste that is savory, umami-rich, and pungent, often compared to strong cheese. Its flavor profile can be an acquired taste for some people, but it is well-loved in Japan and appreciated for its distinctiveness and health benefits.

Rotten food is the result of spoilage caused by harmful bacteria or fungi, which can lead to unpleasant odors, flavors, and potential health risks. Fermented food, on the other hand, is created through a controlled process involving beneficial microorganisms like bacteria or yeast, which transform the food into a more digestible and flavorful form, often with added health benefits.

Yes, fermented foods are generally good for your gut health. They contain probiotics, which are beneficial bacteria that help maintain a healthy balance in your digestive system. Consuming fermented foods can improve digestion, boost the immune system, and contribute to overall well-being. The effects of probiotics are enhanced when they are consumed with prebiotics. Prebiotics are a type of non-digestible fiber found in certain fruits, vegetables, and whole grains that act as food for the probiotics. By providing the probiotics with the nutrients they need to thrive, prebiotics help the probiotics work more effectively and promote a healthier gut environment. Combining probiotics and prebiotics in your diet can lead to improved digestion and overall well-being.

Natto should be stored in the refrigerator, preferably at temperatures between 35°F and 40°F (2°C and 4°C). Keeping it in its original packaging or a sealed container will help maintain its freshness and prevent the absorption of other odors in the fridge.

Yes, you can freeze natto to extend its shelf life. To freeze natto, place it in an airtight container or a resealable plastic bag, making sure to remove air as much air as possible. Frozen natto can last for several months, but it’s best to consume it within 3-4 months for optimal quality. When you’re ready to eat the natto, thaw it in the refrigerator for a few hours or overnight before serving.

However, keep in mind that natto generally tastes better and has more active bacteria when it’s eaten fresh. Freezing may slightly alter the texture and taste, so for the best natto experience, it’s recommended to consume it fresh whenever possible.

Natto has been found in studies to act as a blood thinner, providing many beneficial health effects. If you are already taking blood thinning medication, you may wish to consult with your doctor before regularly consuming natto.

After fermentating our natto, Aya’s Culture Kitchen refrigerates natto for a minimum of one day.  During this initial refrigeration period, important proteins and enzymes are formed, which help give natto its unique taste.  Brand new natto that has been refrigerated for only one day has the mildest taste.  While some people prefer this taste, others say that natto tastes best after about two weeks of refrigeration from the production date, as its natural flavors deepen.  We encourage you to experiment with our natto to decide the aging period you like best.

There are in fact some huge sustainability element to our business. Almost all natto in the US until now has been frozen (using energy) and shipped 6,000 miles. In addition, a big portion of the dried soybeans used for making natto in Japan are actually imported from the U.S. So, for starters we are eliminating that. As to the containers themselves, while we are not permitted to bring outside containers back into our kitchen as we cannot allow any possibility of contamination at all, our customers are telling us they reuse these containers for food storage. That said, if you have any other ideas, please share them with us! 

The shelf life of natto can vary depending on a variety of factors, including the consistency of the temperatures in your fridge. Over time it will take on a stronger flavor. Some people prefer the mild flavor of “fresh” natto, while others prefer natto that has aged for several weeks. Eventually natto will develop white, sand-like granules. These are amino acid crystals known as tyrosine. These crystals are not harmful, but they can alter the texture and flavor of the natto. When you notice these crystals, it is time to discard it.

For shipments within the U.S., our nattos are available in quantities of 16, 24, and 36 packs. We previously experimented with offering smaller sampler options, including 2-pack and 6-pack configurations. However, we encountered a challenge: some customers reported that some containers were damaged during shipment. Unfortunately, we haven’t yet found sufficiently robust packaging solutions for these smaller quantities. As a result, we currently limit our shipping options to 16, 24, and 36 packs to ensure product integrity upon arrival.

For customers in the New England area, we offer a more flexible purchasing option at our farmstand. Here, you can buy any quantity of natto, starting with just one pack. Additionally, we’re actively working on making our nattos available in Japanese and Asian supermarkets across the U.S. We’re committed to keeping our customers updated on this progress and hope to provide more versatile purchasing options in the future.