Tastes in Native Japanese words

We have five tastes - sweet, sourer, hot (spicy), salty, bitter, - plus one more "tannin taste".

sweet - ama-i (あまい、甘い)
sourer - suppa-i (すっぱい、酸っぱい)
hot (spicy) - kara-i (からい、辛い)
salty - shio-kara-i (しおからい、塩辛い) or shoppa-i (しょっぱい)
bitter - niga-i (にがい、苦い)
"tannin taste" - shibu-i (しぶい、渋い)

As the last syllable of each word has  "-i "(pronounced as not " ai " but " yi  ") they are all adjectives. The noun forms are quire regular

1) showing the degree of taste

degree of sweetness - ama-sa (あまさ)
degree of sourerness - suppa-sa (すっぱさ)
degree of hotness (spiciness) - kara-sa (からさ)
degree of saltiness - shio-kara-sa (しおからさ) or shoppa-sa (しょっぱさ)
degree of bitterness - niga-sa (にがさ)
degree of "tannin taste" - shibu-i (しぶさ)

-sa (さ) is the Japanese Native suffix changing an adjective to a noun

and

2) showing xxxx-ness itself

sweetness - ama-mi (あまみ)
sourerness - suppa-mi (すっぱみ)
hotness (spiciness) - kara-mi (からみ)
saltiness - shio-kara-mi (しおからみ) or shoppa-mi (しょっぱみ)
bitterness - niga-mi (にがみ)
"tannin taste" - shibu-mi　(しぶさみ)

-mi (み) is the Chinese origin suffix from Chinese origin (mi, 味) (meaning " taste" ) changing an adjective to a noun.  Chinese word 味 is now pronounced as <wei> in Mandaline (Putonghua) but as pronounced <mei> in Cantonese and may have been as <mi> or similar pronunciation in some time and somewhere close to Japan so <mi> is unlikely to the native Japanese.

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