После обминки тесто стало плотнее.

Because после requires the genitive case.

The base noun is обминка. In the genitive singular, it becomes обминки.

• обминка → nominative singular
• обминки → genitive singular

So:

• после обминки = after kneading / after punching down / after folding the dough

This is a very common pattern in Russian:

• после урока = after the lesson
• после работы = after work
• после дождя = after the rain

In a baking context, обминка means working the dough after it has risen—often punching it down, folding it, or gently kneading it again.

It does not always mean the very first kneading of the dough. It usually refers to a later stage, when the dough is pressed down or reworked after fermentation.

So in this sentence, после обминки is something like:

• after punching the dough down
• after re-kneading
• after folding the dough

The exact English translation depends on the baking context.

Because the subject is тесто, and тесто is a neuter noun.

In the past tense, Russian verbs agree with the subject in gender and number:

• стал = masculine
• стала = feminine
• стало = neuter
• стали = plural

So:

• тесто стало = the dough became

This is a very important agreement pattern in Russian past tense.

Here стать means to become.

So:

• тесто стало плотнее = the dough became denser / firmer

Russian often uses стать + adjective/comparative to show a change of state:

• стало холодно = it became cold
• она стала спокойнее = she became calmer
• суп стал вкуснее = the soup became tastier

In this sentence, the dough changed its texture, so стало is the natural choice.

Because плотнее is the comparative form of плотный.

• плотный = dense, firm, compact
• плотнее = denser, firmer, more compact

The sentence is describing a change: after the dough was worked, it became more dense/firm than before.

Compare:

• тесто плотное = the dough is dense/firm
• тесто стало плотнее = the dough became denser/firmer

So плотнее is used because the idea is becoming more X.

It can mean several related things, depending on context.

With dough, плотнее can suggest:

• denser
• firmer
• tighter in texture
• less airy

A literal translation might be denser, but in natural English baking language, firmer may sound better in some contexts.

So the Russian word is slightly broader than a single fixed English equivalent. The exact best translation depends on what the speaker wants to emphasize.

Тесто is the subject of the sentence, so it is in the nominative case.

The sentence structure is basically:

• После обминки = after kneading/punching down
• тесто = the dough
• стало плотнее = became denser/firmer

Since тесто is the thing doing the becoming, it stays nominative.

Also, тесто is one of those neuter nouns ending in -о, so its nominative singular form already looks simple:

• тесто = nominative singular
• теста = genitive singular
• тесту = dative singular

Here, nominative is correct.

Yes. Russian word order is flexible.

You could also say:

• Тесто стало плотнее после обминки.

This means the same thing.

The original order:

• После обминки тесто стало плотнее.

puts the time/condition first: after kneading...

That can feel slightly more natural if the speaker wants to frame the result in relation to that step.

So both are correct, but the emphasis shifts a little.

Yes, in standard Russian, после takes the genitive case.

Examples:

• после завтрака = after breakfast
• после встречи = after the meeting
• после обеда = after lunch
• после обминки = after kneading/punching down

So this sentence is a good example of a very common rule.

Yes, but плотнее is more natural here.

Russian has two common ways to form comparison:

1. simple comparative

   • плотнее = denser / firmer

2. analytic comparative

   • более плотный = more dense / more firm

After стать, Russian very often prefers the simple comparative:

• стало плотнее sounds natural
• стало более плотным is possible, but heavier and less everyday

Also note that with более плотным, the adjective would usually appear in the instrumental case after стать:

• тесто стало более плотным

So yes, it is possible, but стало плотнее is simpler and more idiomatic.

The stresses are:

• после́
• обми́нки
• те́сто
• ста́ло
• плотне́е

Stress is important in Russian because it is not always predictable. A learner might especially want to notice:

• обми́нка → обми́нки
• плотне́е has stress on -не́-

Saying the stress correctly will make the sentence sound much more natural.