Whenever we get toro tuna from Catalina, it is a challenge to finish the dark red portion of meat called "chiai" 血合い. It is the most undesirable and gamey part of the tuna. In the past, I made chiai, nattou and egg yolk and chiai burger. This time, I made several long cigar-shaped spring rolls from marinated chiai and nattou. I was afraid of how strong this would taste but the end result turned out to be very pleasant and we enjoyed it as the first snack of the evening.
I got this idea after seeing a recipe for red meat of tuna with nattou wrapped in eggroll skin (which is in the first book of the Japanese Izakaya cookbooks section of this blog).
Tuna chiai: When I prepared the toro, I removed the chiai and cut it into small cubes (1/2-1/3 inch cubes) and marinated in in straight "mentsuyu" 麺つゆ noodle sauce and kept it in the refrigerator for a few days.
Nattou: This was one small package of frozen nattou which I thawed. I added chopped scallion, mustard (1/2 tsp) and mayonnaise (1 tsp) and the sauce that came with the package. I then combined the marinated chiai tuna and nattou (almost all the marinade was absorbed in the chiai).
Spring roll skin: I cut the square egg roll skin in half to make a long rectangle. I placed the the above mixture along the near end of the spring roll skin and rolled into a cigar shape using a mixture of flour and water as a glue at the three edges. With the amount of the stuffing I had, I could make 5 rolls.
Instead of deep frying, I shallow fried the rolls. I used less than 1/4 inch of peanut oil in the frying pan. After the oil heated up on medium flame, I placed the rolls seam side down into the oil. I fried them for several minutes and then turned them over (see below). I fried the other side for another two minutes or so until the spring skins were nicely browned and crispy. I drained the excess oil on a paper towel line plate and served the rolls in a small wine grass as seen in the first picture.
I did not make any dipping sauce since everything was well seasoned especially the chiai. Despite the combination of two very strong tasting items (chiai and nattou), the frying seems to have brought the flavors under control—this actually tasted rather tame. The nattou was not too smelly or sticky. The marination and cooking also made the chiai rather palatable and, of course, the crispy fried egg roll skin was just great. So this is another good way to consume the chiai of tuna.