Tips on reducing harshness/astringency?

[kwhubby]

Hello,

Without going too much into the specific recipes, I'm trying to determine variable sources of harsh, hot and astringent flavors in gin distilling. What are some adjustments you discovered that made the final product more or less harsh?

Some specific I wonder the relative impact of:  character of neutral base spirit,  heads and tails cut point, maceration time, temperamental or normally hot/harsh/spicy herbs.

In terms of herbs, I'm curious of which can become culprits for imparting "harshness" if used improperly, some I'm suspicious of: juniper, citrus peel, angelica, cassia, cinnamon, rose, black pepper, cubeb, caraway, cardamom, licorice...

I'd love to hear some experiences.

 

 

[delta H]

I'd highly suggest that the problem is likely the neutral.  Do you make your own, and what equipment do you have to do so? If you are toting, do you rectify it - if not you'd be surprised by the fores/heads that remain in column-produced GNS that are relatively easy to pull off with a batch pot and column.

 

Now, if you are satisfied with the spirit (and we only make gin out of spirit we'd be happy selling as vodka/soju, in terms of quality), then the botanicals can be a thing.  Generally speaking, there are some 'hot' spices, like pepper (of various types), ginger, cassia - overdoing those can be unpleasant (though it can be good in a mixed drink - how is your product going to be used - we make a gin to mix and a couple gins to sip, they are very different profiles). Vapor is generally less harsh than macceration, and with vapor (if you have a good setup), you can decide when a batch is done by taste before you pull the laties out in the distillate.

 

[adamOVD]

Is the astringency coming through at a certain point during your run? Odin has a great post called odin on gin that describes when in the run different botanical flavors are more pronounced.

[kwhubby]

Thanks for the reply.

delta H:

For me the neutral is purchased. The spicy run was with some wheat spirit. The wheat alone, diluted to vodka strength has a rather spicy astringent finish to begin with. Perhaps cleaning it with extra run in the still or some carbon filtering would help?  For the spices, there aren't any of those listed at the moment, the closest is cardamom. Can any others become harsh?

adamOVD:

For me, the astringency seemed like it coming through strongly during the beginning of the run, but very noticeable until maybe 15-20% through. But cutting the heads seemed to harm the good characteristics of the aroma and finish too much. Reading Odin's posts I've seen the familiar ratio chart from another website. Some of the
X/100 herbs I break the rule, particularly lemon peel, orris root and flowers, I found X/100 far too weak. Peels and Orris root I'm more like X/30 each.
 

[adamOVD]

I'm no expert and usually restrict myself to answering questions on fermentation, but if it come through early I'd be suspect of heads as mentioned, and the lighter botanicals. Just some ideas, Any pith on your citrus? Are you over grinding your juniper?

[Glenlyon]

23 hours ago, kwhubby said:

The spicy run was with some wheat spirit. The wheat alone, diluted to vodka strength has a rather spicy astringent finish to begin with.

Really? That should be a soft creamy flavor with an ever so slightly sweet finish. Our gin (using a very smooth wheat base) has about a dozen botanical elements including pepper, ginger (but not cardamon, which I don't like) and we proof to 40% alc/vol which tends to smooth things out a bit more. We also strive to remove as many of the oils as possible during the run - which, we believe also makes a difference. And finally, if I don't like what I tasting during the run, I swap out the botanical basket and insert a new one with a modified load on the fly.   

[kwhubby]

23 hours ago, Glenlyon said:

Really? That should be a soft creamy flavor with an ever so slightly sweet finish. Our gin (using a very smooth wheat base) has about a dozen botanical elements including pepper, ginger (but not cardamon, which I don't like) and we proof to 40% alc/vol which tends to smooth things out a bit more. We also strive to remove as many of the oils as possible during the run - which, we believe also makes a difference. And finally, if I don't like what I tasting during the run, I swap out the botanical basket and insert a new one with a modified load on the fly.   

Interesting that wheat should have those  characteristics.

Removing oils? as in discarding heads?

Botanical basket! So you are not doing a pot still with maceration, or are you doing both?
 

[Glenlyon]

When you say spicy, I think of rye.

My gin still is a basic pot still with a gin basket. Very simple. We do generally use the gin basket stuffed with juniper and the other botanicals which we change out often during the run. We collect a lot of oils and other stuff, liters of it. It smells great and even tastes kinda OK. My wife wants to make soap with it.

The downside to this strategy is it's difficult to duplicate the results perfectly run after run - which, is OK for us as our clients see that as a great reason to keep coming back. For a bigger operation though - this would not be desirable. Now that I've produced so much of it, I'm seeing basic consistencies that come from the same guy doing the same thing. If I were to die though, that would be a problem...

[kwhubby]

But rye is a nice warm zesty pleasant spicy. I'm talking an astringent, harsh, almost chemical or metalic, bitter burning flavor.
It may very well be one or any of the factors mentioned thus far: base spirit, lemon pith, ground juniper, or excess "lighter botanicals".
I'd be very curious to see a chart or article describing what "lighter botanicals" are and where they predominantly come through in a run, such a diagram could help narrow things down. From observations it seems the aromas of pine, menthol, flowers, are first with lemon and cardamom close behind.

 

[delta H]

"... I'm talking an astringent, harsh, almost chemical or metalic, bitter burning flavor."

 

That doesn't sound like botanicals to me. I'd look at the base spirit (which can be hard to clean up if you don't have the correct gear), your water (are you treating your water, at every point - still charge dilution, and distillate dilution), or maybe your still (dissolving gaskets, residual cutting oil, etc - try brushing out your condenser/parrot and see if there is crap in it).

[Glenlyon]

Assuming you tasted your spirit before actual made the gin, it should have been acceptable or you probably would not have procceeded. Therefore, any new problems would have been introduced by the botanicals. Upon reviewing your post I notice 'ground juniper' - now - that's going to be pretty sharp I would imagine. I have heard it's best to keep the juniper whole or only slightly crushed.

[SpiritedConsultant]

Pith on the lemon peel can contribute astringent off-flavors. Low quality caraway can give harsh chemical flavors.

What type of still are you using? What is it made of and how is it heated? How long is your run? What abv are you charging at? Are you crushing and/or macerating your botanicals?

[kwhubby]

Delta H:
Water: is always RO water, it tastes good; all metal parts of still were obsessively cleaned (acetone, scrubbing, acid, base, steam, sacrificial alcohol runs).

Would a simple reflux column and carbon filtration be insufficient for improvement?

Glenlyon:

Yes the base spirit seemed "acceptable", however the base spirit certainly could be improved, it's noticeable when tasted next to premium bottled vodkas that the spirit has room for improvement.

I question the ground vs crushed vs solid botanical question. Wouldn't maceration and the heat from distillation extract the entire profile of compounds regardless of grinding? I would think the grinding would accelerate or improve the efficiency of extraction but not fundamentally change the taste (at equal concentration extracted).

SpiritedConsultant:

I know about pith, perhaps too much residual exists. "Low quality caraway" That's an interesting tip! How does one judge caraway quality? Would extracts from different caraway sources need to be created?

Pot still; combination of stainless steel and copper parts; submerged electric coil; 55%; crushed and macerated for 3 days.

What is a reasonable duration for a given volume of spirit (or boiler)?

 

 

[Glenlyon]

1 hour ago, kwhubby said:

Wouldn't maceration and the heat from distillation extract the entire profile of compounds regardless of grinding?

No. The juniper berry, as it were, is actually a small tree cone, within which, a multitude of tiny seeds reside. When you grind it, you break open these seeds and the harsh interior is exposed along with strong undesirable flavors. When you macerate or distill whole or slightly crushed berries directly through the gin basket, you are gently easing out the compounds you want. You don't want to be heavy handed - and - you don't want to be too light - you want the Goldilocks amount. That why building and scaling gin is such a difficult task. I've come to view making gin as one of the most artistic yet challenging aspects of distilling. I hold good gin in high esteem.  

[spiritzzz]

Could the botanicals be touching the heating element and burning? I suspect this is an under-diagnosed source of various issues (?)...