The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Acetone smell from mature starter

Jefftow's picture
Jefftow

Acetone smell from mature starter

my starter is around 9 months old, I use the scrapings method and store in fridge between uses.

never had a problem until I took it out a couple days ago. But I fed it 50/50 rye/water.

left it few hours there were bubbles forming I had a sniff and strong acetone smell fed it some more as I’d heard that hungry starters can have this smell, I’ve fed twice a day and smell persists.

its 50/50 rye and water ever since I started it.

any ideas I’m worried it will make sour bread as I like a mild taste

Mini Oven's picture
Mini Oven

Feeding has three parts.  How much starter, water and flour?

Just to be clear, what is the "scrapings method?"

Jefftow's picture
Jefftow

the Scrapings method is where you keep starter in the fridge with just a very small amount of starter maybe a teaspoon 

when you want to bake you take it out and feed it over 2 days 

I feed 30grms water 30 grams rye twice a day that gives me roughly 260 grams 

I use 200 to make bread and maybe put 30 grams back in fridge till next time.

saves waste or finding things to do with excess starter.

my starter can triple in size in 8 hours once it gets going and has never been a problem till now

i took it out of the fridge and it smelt of acetone, I heard that this happens when it’s hungry so I kept feeding it it grew really well plenty of bubbles but smell won’t go 

Mini Oven's picture
Mini Oven

you take 5g starter and feed 30g water and 30g flour for about 65g starter  (a ratio of 1:6:6.   s:w:f )

then tale that 65g and feed 30g water and 30g flour for 125g. ( end of first day, ferment overnight) (a ratio of 2:1:1)

second day feed 125g  starter 30g water and 30g flour for 185g to ferment and then feed (a ratio of 4:1:1)

185g roughly 30g water and 30g flour to make 240g starter. To use on the third day.   (A ratio of 6:1:1)

Is this correct?

Jefftow's picture
Jefftow

Yes that’s about correct Mini

Mini Oven's picture
Mini Oven

Do you see the distuctive feeding pattern? 

I would suggest a different feeding patter so that the starter is not forced to self destruct on day two.

Try 1:4:4  the day before mixing up your dough.  Feed starter 5g with 20g each water and flour. (Morning)   and when it peaks take that 45g and feed it 100g  each water and flour for a total of 245g to ferment overnight.  Then make your recipe in the morning.  

 

Jefftow's picture
Jefftow

Thank you mini, do you think my feeding pattern caused the acetone

gary.turner's picture
gary.turner

Acetone is indicative of underfeeding; the wee little beasties don't have enough sugar and the Krebs cycle is disrupted. They begin feeding on the fats, proteins and even themselves (autolysis).

Jefftow's picture
Jefftow

thank you for the help Mini and Gary. Lesson learnt new starter on the way.

i washed my old jar 3 times and rinsed with very hot water and can still smell it so Bruce has a new jar