Learn Hardcore Japanese: ryourihon wo yomikaesu uti ni, onazi satou to sio de mo irekata de azi ga kawarukoto ni kidukimasita. - As I reread the cookbook, I realized that even with the same sugar and salt, the taste changes depending on how you put them in.

〜うちに often implies:
- a gradual discovery or change over the course of an activity, and
- that the change is somewhat unplanned / noticed naturally.
〜間（あいだ） focuses more on a time span:
- 料理本を読んでいる間 = while I’m reading the cookbook (during that time)
- 料理本を読み返すうちに = as I kept rereading (over time) I came to notice…

So うちに here emphasizes that in the process of repeated rereading, the speaker gradually realized something, rather than just saying “during the time of reading.”

Why is it 料理本を読み返すうちに and not something like 料理本を読んでいるうちに?

Both are grammatically possible, but the nuance is a bit different:

読み返すうちに (yomikaesu uchi ni)
- 読み返す = “to read again, to reread”
- Suggests you repeatedly reread cookbooks, or at least went back over them.
- Implies the realization came from repeated exposure and accumulated experience.
読んでいるうちに (yonde iru uchi ni)
- More like “while I was reading (them)”
- Emphasizes a continuous ongoing action rather than repetition.

Using 読み返す fits better with the idea that the speaker gradually understood something by rereading many recipes or books over time, not just in one reading session.

What exactly does 砂糖と塩 mean here? Is it just “sugar and salt”?

Yes, 砂糖と塩 (さとうとしお) is simply “sugar and salt.”

砂糖 = sugar
塩 = salt
と = “and” (linking two nouns)

In context, 同じ砂糖と塩でも means roughly:

“even with the same sugar and salt”
- same kind/brand, or same amounts, depending on context.

So it’s saying: even if you use the same ingredients (sugar and salt), the flavor can change depending on how you add them.

What does でも in 同じ砂糖と塩でも mean? Is it the same as sentence-initial でも (“but”)?

This でも is not the sentence-connector “but”.

Here, でも is:

で (particle) + も (particle “even, also”)
Together functioning as “even (with) …”

So:

同じ砂糖と塩でも ≈ “Even with the same sugar and salt”
- “Even if the sugar and salt are the same”

Compare:

Sentence-initial でも、〜 = “But, however, …”
Noun + でも = “even N,” “N too / N also (in such a case)”

In this sentence, it clearly belongs to the noun phrase:

同じ砂糖と塩でも入れ方で味が変る
→ Even with the same sugar and salt, the taste changes depending on how you add them.

What does 入れ方 mean, and how is it formed from 入れる?

入れ方 (いれかた) literally means “the way of putting in / the way of adding.”

Formation:

Verb 入れる (ireru, “to put in, to add”)
Replace the ます-stem form (入れ-) + 方 (かた) = 入れ方

Verb stem + 方 = “the way of doing [verb]”

Examples:

切る → 切り方 = the way of cutting
作る → 作り方 = the way of making
読む → 読み方 = the way of reading

So 入れ方 here means how you add the sugar and salt:

timing (before/after something else),
order (salt first, sugar later, etc.),
method (dissolved first, sprinkled later), etc.

What is the role of で in 入れ方で味が変る?

In 入れ方で味が変る, the particle で indicates the basis / cause / means by which something varies:

入れ方で = “depending on the way (you) add [them]” / “by the way of adding”
味が変る = “the taste changes”

So 入れ方で味が変る means:

“The taste changes depending on the way you add them.”
“The taste changes based on how they are added.”

This で is similar to:

人によって考え方が違います。
→ Ways of thinking differ *by person.*
場所で値段が変わる。
→ The price changes *depending on the place.*

Here it’s: 入れ方で → by / according to the way of adding.

What is the function of こと in 味が変ることに気づきました?

こと is a nominalizer here: it turns the clause 味が変る (“the taste changes”) into a noun-like phrase.

味が変る = “the taste changes”
味が変ること ≈ “the fact that the taste changes” / “the thing that the taste changes”

Then:

〜に気づく = “to notice ~” (with に)

So:

味が変ることに気づきました。
= “I noticed that the taste changes.”

Without こと, you can’t attach に気づく to that entire idea.
こと packages the whole event “the taste changes” into a single object that can be “noticed.”

Why is it 気づく with に (ことに気づきました) and not something like 味が変ることが分かりました?

Both are possible but have different nuances.

〜に気づく:
- Focuses on the moment of becoming aware of something.
- Suggests: “I hadn’t really realized this before, but at some point I became aware of it.”
- 味が変ることに気づきました。 = “I noticed / came to realize that the taste changes.”
〜が分かる:
- Focuses more on understanding or knowing something.
- 味が変ることが分かりました。 = “I understood / found out that the taste changes.”
- Often used when you learn something via explanation, evidence, testing, etc.

In the context of rereading cookbooks and gradually realizing a subtle cooking point, 気づく (sudden or gradual realization/awareness) sounds more natural than 分かる, which can feel more like being “told” or “informed.”

Why is 気づきました in the past tense, but 変る is in the non-past form?

Japanese handles tense inside embedded clauses a bit differently from English.

The main verb of the sentence is:
- 気づきました (past polite): I noticed / I realized
Inside the embedded clause:
- 味が変る uses the non-past form.

Here, 味が変る expresses a general, timeless fact:

“the taste changes (in general, whenever you do X)”

So the structure is:

(General fact) 味が変る
I (in the past) noticed that fact → 気づきました

English often also keeps the inner clause in present for general truths:

“I realized that the taste changes depending on how you add them.”

So:

Past tense marks when you came to that realization,
Non-past inside marks the nature of the fact (a general truth).

Is 変る a mistake? I thought it should be 変わる.

You’re right that in modern standard writing, the common spelling is:

変わる (かわる)

The form 変る (without the わ) is:

An older / alternative spelling that you still sometimes see, especially in some printed materials, or as a stylistic choice.
Not “wrong” per se, but less common today in everyday writing.

So you can safely treat 変る here as 変わる.
Meaning:

味が変わる = “the taste changes / tastes change”

What does 同じ modify in 同じ砂糖と塩でも? Does it apply to both sugar and salt?

Yes, 同じ (おなじ) here naturally applies to the set “sugar and salt” as a whole:

同じ砂糖と塩 ≈ “the same sugar and salt”

Interpretations in context:

Either:
- Same type/brand of sugar and of salt as before, or
- The same quantities of sugar and salt.
The exact nuance depends on the broader context, but the key idea is:
- The ingredients themselves are the same; the difference comes from how you add them.

So the phrase contrasts:

ingredients (same) vs. method of adding (different)
and then explains that the method still makes the taste change.