Crisp Marris Otter - Anyone reporting any issues?

[arturobandini]

Ordered a sack of Crisps Marris Otter as the Pale Malt I used last time was out of stock at the Malt Miller. The previous batch was excellent and I had great efficiency with it as recent as August when brewing an IPA which achieved an O.G in excess of the 75% efficiency estimation.

This sack of Marris Otter has seen me underhit my O.G. targets on every brew I've brewed with it so far. Whether that was 1.054 ESB coming in at 1.050 or my American Stout from last night coming in at 1.060 instead of estimated 1.063 based on 75% efficiency.

Anyone else suffering from a low efficiency with the Crisp Marris Otter or have I just gone crap in a couple of months? Nothing in my brewing technique (if it can so be called) has changed so I am laying the blame, probably unfairly, with the malt.

[seymour]

I haven't used this exact maltster, so I'm answering in generalities. The sort of variation you suspect is certainly possible, and is just the sort of thing commercial brewers monitor and compensate for. What to do about it is your choice, but some options include: increasing the quantity of base malt by about 5%, decreasing mash temp 1 or 2 degrees, and/or lengthening your mash duration about 30 minutes. In the olden days, this was one of many variables which was (partially) controlled by blending new and old batches before serving.

[weiht]

Was it pre-crushed? The issue may be in the different crush, especially when its 25kg sack of grains, its not easy to judge the flour/husk ratio and keep it consistent with every brew.

[arturobandini]

Thanks for the replies chaps.

When I buy a malt it is for pre-determined recipes so when it arrives I bag up each recipe in separate sacks and store until use. I'm on my fourth brew out of six tonight so I'll see if it is a mix of flour and malt ratio or perhaps just a variation in the malt as Seymour suggests.

Just wondered if anyone was experiencing a loss in efficiency as a result of this particular malt.

In terms of 'fixing' the problem, i'm not that bothered to be perfectly honest. We are talking small percentages of difference rather than whopping great disparities so I'll 'suck it up' for now and if it happens with in my next brew marathon then it's definitely me!

[alix101]

I belive that the it all depends on the harvest, where and when it was grown. The wet weather has had an effect on the barley crop, so i dont think its down to the malting just the quality of the growing conditions.

[Kev888]

I got some around late september/early august time from Rob if thats of any use - seems to be working normally for me.

I have had this variation in the past with other brands, so as mentioned by others its not impossible even from the same harvest. Sometimes though I suspect other influences, like it being winter and not quite compensating enough for temperatures or getting different evaporation rates and so on - admittedly I'm not the most fanatical of brewers when it comes to precision, but it doesn't seem to take a lot for me to go +/- a couple of points or so.

Cheers
Kev

[Beer O'Clock]

I've found, like Kev, that there are many other variables that can also account for variations in figures. I noticed an extraordinary variation in boil off volumes according to relative humidity.
Also (I buy 25kg sacks) the relative volume of flour to crushed grain can have an impact. Are you using the entire contents of the bag of crushed grain ?