Mangrove Jack's PINK GRAPEFRUIT IPA Low SG?

The Homebrew Forum

Help Support The Homebrew Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Berry454

Well-Known Member
Joined
Feb 2, 2021
Messages
175
Reaction score
72
Started a kit brew the other day, the mangrove Jack's pink grapefruit IPA. This kit should finish on 5.7% abv.

I started the brew at 18 litres as I didn't want the fermenter to foam over. At 18 litres the SG is only 1.050??

From my estimation that's about 5.7% abv. But I still need to top the fermenter up to 23 litres which will lower the abv.

Brew starts at 1.050 at 18 litres. After topping up to 23 litres, what can I estimate the gravity to be? Or what can I estimate the abv to finish on? Keeping in mind these kits usually stop fermenting about 1.010.
 
18 litres @ 1.050 is 23 litres @ 1.039

Thank you. 1.039 finishing at 1.010 is literally 3.39% abv.. very low compared to 5.7% 😐

Hence I need about 500g of sugar added which should give about another 1.3% at 23 litres.
 
That does seem a very low SG. Was it all stirred thoroughly and gravity taken before yeast pitch?
Yes gravity was taken before yeast pitch and everything was shaken thoroughly (not stirred) as it's in a carboy (demijohn).

The only thing I done different was added the kit to warm water when the kit said it should be boiling water. I used warm water as the fermenter is made of PET and not suitable for boiling water.

I did shake the living hell out of the fermenter for about 20 minutes and nothing is stuck to the bottom.

Would you recommend additional sugar added?
 
Don't these kits specify that you need to add X amount of extract/sugar in addition to the stuff in the bag?
1.2kg of MG enhancer gives 15 OG points which will bump you up to 1.054
 
Interesting post for me since I'm 5 days into the fermentation of a Mangrove Jacks Grapefruit IPA.
I added the recommended 1.2 Kg of Malt enhancer. Everything diluted and stirred well.
SG before yeast added: 1048
Pitched temp 22 degrees
Fermentation took a day and a half to get going but then zoomed off and foamed over the bucket top. A very thick and sticky light brown mess. In fact it did it twice.
Temp kept around 20 degrees. Never over 23. Never less than 19.5.
Never had this happen before. 23 litres in the bucket.
Should I have kicked off with less in the bucket? and then topped up?

Cheers
 
Don't these kits specify that you need to add X amount of extract/sugar in addition to the stuff in the bag?
1.2kg of MG enhancer gives 15 OG points which will bump you up to 1.054
Yes. 1.2kg of MJ light extract or 1kg of brewing sugar wil be needed. Some of their kits they don't recommend sugar so check first.
 
Interesting post for me since I'm 5 days into the fermentation of a Mangrove Jacks Grapefruit IPA.
I added the recommended 1.2 Kg of Malt enhancer. Everything diluted and stirred well.
SG before yeast added: 1048
Pitched temp 22 degrees
Fermentation took a day and a half to get going but then zoomed off and foamed over the bucket top. A very thick and sticky light brown mess. In fact it did it twice.
Temp kept around 20 degrees. Never over 23. Never less than 19.5.
Never had this happen before. 23 litres in the bucket.
Should I have kicked off with less in the bucket? and then topped up?

Cheers
I've doing this kit now, and exactly the same as me!.. I used the 1.2kg malt enhancer and into the FV at 1.050SG, so about 7 points lower that it should be IIRC and constant 20C.. nothing for nearly two days. As the kit + yeast was past its best before by a good year, I decided that the yeast may have not been viable enough so to prevent yeast stress, I chucked in a pack of verdant. next day it was everywhere lol!... took a couple of days to calm down to a sensible pace enough that it was worth cleaning up..

Can't say for sure if the M44 yeast was doing much, but there wasn't any pressure whatsoever in the FV when I pulled the PRV prior to pitching the verdant, and the spunding valve was rock solid on 0PSI. I don't know how much M44 was actually responsible for it going nuts as verdant is known for going off well.
 
Latest update: I added the hops on day 6 after clearing off the top gunk. ( what's the technical term? ).
SG was 1020.
Much calmer now. Maybe the hop 'cap' is keeping things calmer?

I've never had such a volatile fermentation. Interesting than someone else had the same experience.
 
Latest update: I added the hops on day 6 after clearing off the top gunk. ( what's the technical term? ).
SG was 1020.
Much calmer now. Maybe the hop 'cap' is keeping things calmer?

I've never had such a volatile fermentation. Interesting than someone else had the same experience.
Did you check the SG b4 adding the hops as 1.020 seems on the high side to me. Even if there's not much if any apparent activity from the airlock, the yeast may still be 'working'. I'd usualy wait until day 12ish, check gravity, if OK add hops then bottle 2 days later. If you add hops too soon and your brew is still fermenting, you will lose a portion of the volatile oils from your hops that ideally you want to keep in your finished brew. Patience is your best friend.
 
Good point. I'm sure I went by the instructions. They say add hops when SG is 1025 or below for pure malt liquid extract.
Good advice though.
I know I should take my time but I left it late starting by brew.
I fly out for a month+ to USA on Nov 4th so want to be able to leave the bottles in a warm environment before moving out to the cool/cold garage.

Fingers cross.

Thanks again

Matt
 
I've doing this kit now, and exactly the same as me!.. I used the 1.2kg malt enhancer and into the FV at 1.050SG, so about 7 points lower that it should be IIRC and constant 20C.. nothing for nearly two days. As the kit + yeast was past its best before by a good year, I decided that the yeast may have not been viable enough so to prevent yeast stress, I chucked in a pack of verdant. next day it was everywhere lol!... took a couple of days to calm down to a sensible pace enough that it was worth cleaning up..

Can't say for sure if the M44 yeast was doing much, but there wasn't any pressure whatsoever in the FV when I pulled the PRV prior to pitching the verdant, and the spunding valve was rock solid on 0PSI. I don't know how much M44 was actually responsible for it going nuts as verdant is known for going off well.
How's it going? Have you added the hops yet?
 
Yeah a couple of days ago, will prob start the cold crash in a day or so and get the beer out and kegged prob at the weekend
Thanks. I bottle mine. Tomorrow I'll rack off into another bucket with a tap and the following day use a bottling wand to bottle into flip top bottles/ crown tops. Leave in the warm house for a week or more until we fly to USA, then pop the lot into the cold garage ready to sample on our return beginning of Dec.
 
I've done this kit recently. SG was bang on 1.050 and it finished on 1.008 giving me 5.5%. Brewed this with 1.2kg of MJ light extract, 12 days at 22 degrees, dry hopped and kegged / bottled 3 days later (mid July). Currently got this on draft and it's great.
 
Last edited:
I've done this kit recently. SG was bang on 1.050 and it finished on 1.008 giving me 5.5%. Brewed this with 1.2kg of MJ light extract, 12 days at 22 degrees, dry hopped and legged / bottled 3 days later (mid July). Currently got this on draft and it's great.
That's the way to do it!
 
I've done this kit three times, exactly per MJ instructions.
SGs 1050 1046 1050.
FGs 1012 1012 1012.
 

Latest posts

Back
Top