Thursday 31 March 2022

How to passivate stainless steel homebrewing equipment


We recently purchased a new stainless steel fermenter. Cheeky Peak Brewery, the manufacturer, recommend passivation of their equipment before first use, and even offer a guide with a few different methods/options on how to accomplish this.

First things first though - what exactly is passivation and why do we need to do it? Well, stainless steel is made from iron, carbon, chromium and other elements - and the chromium content creates a thin layer, known as a passivation layer which protects and prevents oxygen from accessing the iron content of the stainless steel. If oxygen is able to access the iron content - rust deposits will form.

The process of manufacturing, drilling, welding, or using harsh/abrasive cleaners and cleaning agents can break down this passivation layer so it's recommended practice to passivate new equipment before first use - as a type of insurance policy against any issues with the passivation layer. Better to be safe than sorry, right?

The first step with passivating is to thoroughly clean the surface of any residual oils and dirts - powdered brewery wash (PBW) is sufficient for this in most cases - preferably done with warm/hot water. Pretty straight forward and standard for most homebrewers.

Next, we need to treat the surface with an acid. The acid chemically removes any free iron from the stainless surface, which then leaves behind a uniform surface with a higher proportion of chromium than the underlying stainless surface. Upon subsequent exposure to oxygen in the air after the acid treatment, the stainless steel will form a chromic oxide layer over the following 24 to 48 hours.

There are typically four (4) types of acids commonly used to accomplish this;

1. Nitric acid
2. Oxalic acid
2. Citric acid
4. Phosphoric acid

And this is where it gets complicated. Firstly, nitric acid is very corrosive - making it dangerous to use, and is also harmful to the environment, so we're going to opt to not use this one.

Oxalic acid is a strong organic acid that naturally occurs in many known fruits and vegetables like rhubarb, spinach - making it a good candidate to use for passivating. It can be found in a common and popular cleaner called Bar Keepers Friend - and Short Circuited Brewers on YouTube made a video on how to passivate stainless equipment by making a thick paste with Bar Keepers Friend powder. The problem for us though is that in Australia, Bar Keepers Friend is made with citric acid, not oxalic acid like it is in the United States. One important thing to note though is that oxalic acid may remove or fade etched markings on your stainless equipment, so be careful and mindful of this if you decide to use an oxalic acid based solution.

Perhaps this isn't really a problem though, since citric acid is a recommended acid to use for passivating. SS BrewTech, a manufacturer of stainless brewing equipment actually recommend citric acid for passivation since it's environmentally friendly and readily available in most parts of the world. The previously mentioned guide from Cheeky Peak recommend a solution of 4-10% citric acid by weight with clean water for a citric acid passivating solution. Australia's version of Bar Keepers Friend has 5-10% citric acid in it by weight, so perhaps we could use the same process as Short Circuited Brewers YouTube video and make a thick paste by mixing Bar Keepers Friend powder with a little bit of water (they used a ratio of 2:1 BKF to water).

On top of this, NASA have performed a study and comparison on the effectiveness of citric acid and nitric acid when passivating stainelss steel. Looking at the photo comparisons in their report, it's easy to see that citric acid was more effective at preventing rust from occurring when compared to the use of nitric acid.

Lastly, we have the option of phosphoric acid. This is most commonly found in homebrew sanitisers like Star San. We have an equivalent product from KegLand called Stellar San. Numerous sources recommend passivating with a Star San solution five times the recommended strength for general sanitising. The recommend strength is typically 1.5ml/L, so for a 30L vessel this would equate to 225ml of Star San. It's not particularly expensive, but that's still quite a lot to use in one go. And given it's a significantly stronger mix than recommended, it can't be re-used for general sanitising of equipment as the increased strength would potentially lead to off flavours - so we're not really liking this option.

KegLand have a blog post stating that passivation on stainless equipment can be done by simply wiping undiluted Star/Stellar San onto the stainless surface, leaving it for 24 hours then wiping away. However, there are other sources stating that phosphoric acid is not a suitable solution for passivating - like the Australian Stainless Steel Development Association who state that;

"Phosphoric acid will remove rust and sulphide inclusions, but it is not oxidising and will not strengthen the passive film"

There are plenty of other sources stating similar things, so we're thinking creating a paste with Bar Keepers Friend may be the way to go - which would essentially mean we're using a citric acid based solution. 

The wealth of information on the internet on any subject can be a blessing and a curse. A quick google search on methods of passivation led us down this rabbit hole, and we were quickly overwhelmed by the vast amount of (often conflicting) information, hence why we've made this post to help summarise our findings - and also provide sources for our information.

What method do you used for passivating your stainless equipment? Let us know in the comments below.


Related Articles

Passivating our new 304ss Stainless Steel Fermenter

Keg King - Apollo Titan - 30L Stainless Conical Pressure Fermenter - Hands on Review

Tuesday 29 March 2022

Gypsy Fox Brewing Co - Rougey Red Ale - Beer Review

Review Date: 26/3/2022
Brewery Name: Gypsy Fox Brewing Co (Hawkesbury, NSW, Australia)
Beer Name: Rougey - Red Ale

"When the sun goes down, the gypsy fox comes out to play. This cunning, well-rounded brew has a backbone of traditional Golding's hops, and full-bodied Maris Otter malt forward and a dash of roasted barley"

Gypsy Fox - Rougey Red Ale Can

General

Alcohol By Volume (ABV): 5.2% (Standard)



Label/Design: 6/10

Serving Style: Can

Region of Origin: Pacific (Australia, New Zealand)

Style Family: Irish Red Ale

Malts/Adjuncts: Maris Otter, Barley

Hops: East Kent Goldings

IBU's: Unknown

Appearance

Colour: Straw



Clarity

Brilliant Clear Slight Haze Hazy

Collar of Foam & Head Retention

None 

Poor
(Up to 15 secs)

Moderate
(15 - 60 secs) 

Good
(more than 60 secs)


Foam Texture

N/A Thin Fluffy Mousse-Like

Carbonation (Visible)

None Slow Medium Fast-Rising Bubbles

Alcohol Aroma

Not Detectable Mild Noticeable Strong Harsh

Aroma & Flavour

Esters Aroma: None
Phenols: None








Alcohol Taste:

Not Detectable Mild Noticeable Strong Harsh

Hop Pungency:

Mild Moderate Strong Extreme

Hop Bitterness:

Restrained Moderate Aggressive Harsh

Malt Sweetness:

Low Medium High Cloying
(Excessive)

Astringency: 

Low Medium High

Palate/Mouthfeel: 

Light Bodied
(Thin/Watery)
Medium Bodied
(Light + Full)
Full Bodied
(Round, Rich & Creamy)

Palate Carbonation: 

Low Medium High

Length/Finish:

Short
(Up to 15 seconds)
Medium
(15 to 60 seconds)
Long
(More than 60 seconds)





Oxidative/Aged Qualities: None

Gypsy Fox - Rougey Red Ale in the Craftd Alpha glass

Overall

Drinkability: 7/10

Overall Impression: 7/10

Notes

Our first beer review for Gypsy Fox - we stumbled across this one while out and about in the eastern suburbs of Sydney - strange since it's such a long way from their base in the Hawkesbury area. Being a red ale there's plenty of malt backbone and sweetness, with hop flavours being derived from the quintessential British hop - East Kent Goldings. With a mixture of floral, spice and some earthy and herbal notes, it leaves a long lasting dry finish with plenty of palate carbonation . Bittering is well matched without being overpowering. A refreshing change from the usual fruit driven IPA's flooding the market



































Thursday 24 March 2022

Cheeky Peak Brewery - Nano X Flexi Unibucket Fermenter - Unboxing

We recently ordered (and received delivery of) our new 30L Nano - X Flexi Unibucket Fermenter from Cheeky Peak Brewery. Here's some photos and info from our unboxing experience.


Opening the box and we've got our fermenter fitted with the standard lid and a small bag containing the screw in rubber feet on top.


Nano X Flexi Unibucket Fermenter

The fermenter itself, in all it's glory. This is the 30L model so it is quite small - we'd describe it as "cute". Nice and shiny too!

1.5" port opening on the Nano X Fermenter body

I'm not a welder but the welds look reasonably neat - certainly not perfect but more than acceptable.

Looking inside the fermenter from the top - very smooth and no rough edges where the ports are located.

Nano X Flexi Unibucket Fermenter - Front On

Looking at the fermenter front on and there appears to be an extra 1.5" port opening where the thermowell should be - this differs from the picture on the Cheeky Peak Brewery website as indicated by the red arrow below. The website states this should be a 22mm laser cut hole?

Ultimately not a big deal but a noticeable difference. As it turns out, the included thermowell is a 1.5" tri clover connection which will fit in this opening - as seen in the photo below.

The included 1.5" thermowell

This is our first time dealing with a stainless fermenter using tri clover clamps/fittings - we tested installing the included ball valve sight glass and was pleased at how easy, simple and secure these fittings felt - no doubt this is why it's the standard fitting type for most connections in the brewing (and now homebrewing) industry.

We plan to use the ball valve sight glass in the orientation pictured below, so we can see the wort in the sight glass with the ball valve shut. We reached out to Cheeky Peak Brewery to confirm this wouldn't be an issue with pressure fermenting potentially causing the sight glass to break - they advised the sight glass is rated to 40psi so using the ball valve sight glass in this manner won't be a problem.

Nano X Fermenter with Ball Valve Sight Glass fitted

There is also a 12.7mm racking cane that is designed to be put into the end of the above pictured ball valve sight glass

12.7mm Racking Cane (connects to ball valve sight glass)

We like the ability to pressure ferment so we purchased a couple of other bits and pieces to go along with the pressure rated lid that comes with the Flexi Unibucket Fermenter.

Cheeky Peak 1.5" Pressure Release Valve (PRV)

This is the 15psi pressure release valve (PRV). A must have if you're going to be pressure fermenting as the pressure lid is rated to 15psi. It's basically an insurance policy for your equipment to ensure the pressure inside the vessel can never exceed the rated maximum of 15psi.

1.5" Ball Lock Gas & Liquid Posts

We also purchased 1.5" gas and liquid ball lock posts to fit to our pressure rated lid. 

We also purchased some extra clamps, blanking plates and seals for the different connections - some were included with the kit but we wanted some extras and spares just in case. 

Here's a quick graphic to hopefully help others understand the different connections and openings on the Nano X Fermenter body. 


1 - 1.5" - this is where the included thermowell should be fitted

2 - 2" opening

3 - 1.5" opening

4 - 1.5" opening - recommend the ball valve sight glass be fitted here

5 - 1.5" opening - where an additional dump valve would typically be attached to

Rubber feet attached to legs of the Nano X Fermenter

Attaching the rubber feet to the ends of the legs - the finish on the ends of the legs was a little rough

 

A closeup of the 1.5" opening at the base of the unit with and without the end cap and clamp attached

Fully assembled and washed down ready for duties

 

Here's a closeup of the 1.5" tri clover thermowell installed along with a top down photo showing it protruding into the fermenter body

Nano X Fermenter Pressure Lid

Here's a closeup of the pressure lid - which includes 3 x 1.5" openings and a single 3" opening in the centre.

Our pressure lid fully assembled with 2 x 1.5" ball lock posts (1 for gas, 1 for liquid), 1.5" 15psi pressure release valve (PRV) and 3" blanking plate. We plan to use the 3" opening for dry hopping in the future

Under side of the Nano X Fermenter Pressure Lid

Under side of the Nano X Fermenter Pressure Lid - blue part is the rubber seal

Nano X Flexi Unibucket Fermenter - fully assembled with pressure lid

And here's our fully assembled Nano X Fermenter with pressure lid and all fittings attached.

We're very happy and impressed with the quality of this unit, and it's parts/accessories so far. Looking forward to putting getting a brew into it ASAP!

Our next step is to perform passivation to ensure we don't get any metallic off flavours appearing in our beers - check out our post all about passivating stainless steel for more details on what passivation is and how we performed it.

If you want to know more about this range of fermenters, check out our Nano X Fermenter Range Rundown post

Let us know in the comments below what you think of the Nano X Fermenter range.

Related Posts

Cheeky Peak Nano-X Fermenter - Impressions after First Brew

How to passivate stainless steel homebrewing equipment



Tuesday 22 March 2022

Dainton Beer - Jungle Juice Hazy IPA - Beer Review

Review Date: 19/3/2022
Brewery Name: Dainton Beer (Carrum Downs, Victoria, Australia)
Beer Name: Jungle Juice - Hazy IPA

"Welcome to the jungle, baby! Big, thick and packed with dank, tropical juice flavours, this is one jungle you are going to want to get lost in."

Dainton Beer - Jungle Juice Hazy IPA Can

General

Alcohol By Volume (ABV): 6.5% (High)



Label/Design: 8/10

Serving Style: Can

Region of Origin: Pacific (Australia, New Zealand)

Style Family: IPA

Malts/Adjuncts: Unknown

Hops: Unknown

IBU's: 65

Appearance

Colour: Straw



Clarity

Brilliant Clear Slight Haze Hazy

Collar of Foam & Head Retention

None 

Poor
(Up to 15 secs)

Moderate
(15 - 60 secs) 

Good
(more than 60 secs)


Foam Texture

N/A Thin Fluffy Mousse-Like

Carbonation (Visible)

None Slow Medium Fast-Rising Bubbles

Alcohol Aroma

Not Detectable Mild Noticeable Strong Harsh

Aroma & Flavour

Esters Aroma: None
Phenols: None















Alcohol Taste:

Not Detectable Mild Noticeable Strong Harsh

Hop Pungency:

Mild Moderate Strong Extreme

Hop Bitterness:

Restrained Moderate Aggressive Harsh

Malt Sweetness:

Low Medium High Cloying
(Excessive)

Astringency: 

Low Medium High

Palate/Mouthfeel: 

Light Bodied
(Thin/Watery)
Medium Bodied
(Light + Full)
Full Bodied
(Round, Rich & Creamy)

Palate Carbonation: 

Low Medium High

Length/Finish:

Short
(Up to 15 seconds)
Medium
(15 to 60 seconds)
Long
(More than 60 seconds)






Oxidative/Aged Qualities: None

Dainton Beer - Jungle Juice Hazy IPA in the Craftd Alpha glass

Overall

Drinkability: 10/10

Overall Impression: 9/10

Notes

Our first Dainton beer and it's very impressive. Here we have an absolute hop bomb with loads of citrus and tropical fruit flavours. The malt is very subdued as you'd expect as this is another one that's all about the hops. For 65 IBU's it doesn't taste overly bitter, or it's at least well balanced with plenty of hop presence and alcohol to support it. We're guessing there were loads of late hop additions here to get such high IBU's while maintaining fruitiness and drinkability and not having any harsh lingering flavours. 6.5% ABV is very well disguised - a little problematic as this one is totally crushable so more than a couple would hit pretty hard. Highly recommended though - we'll be buying this one again for sure.

































Saturday 19 March 2022

Best Juicy New England IPA (NEIPA) Recipe

After much research and putting together our NEIPA Recipe Creation Guide, we have settled on the below recipe for our Juicy New England IPA (NEIPA) Recipe

Vitals

Batch Volume: 22L 
Boil Time: 30 minutes
Brewhouse Efficiency: 75%

Original Gravity: 1.064
Final Gravity: 1.013
IBU (Tinseth): 30
BU/GU: 0.47
Colour: 9.3 EBC

Mash

Temperature: 65c - 60 minutes
Mash Out: 75c - 10 minutes

Malts

2.2kg - Gladfield Pilsner Malt (35.5%)
2.2kg - Golden Promise Malt (35.5%)
650g - Gladfield Wheat Malt (10.5%)
650g - Flaked Oats (Uncle Tobys Quick Oats) (10.5%)
300g - Gladfield Gladiator Malt (4.8%)
200g - Gladfield Sour Grapes Malt (3.2%)

Hops

Citra (18 IBU) - Whirlpool/Hopstand - 85c for 15 minutes
Azacca (12 IBU) - Whirlpool/Hopstand - 85c for 15 minutes

100g - Amarillo - Dry Hop (3 days)
100g - Azacca - Dry Hop (3 days)
100g - Citra - Dry Hop (3 days)

Yeast

2 packets of dry yeast to be co-pitched

Lallemand Verdant IPA (Dry - 1 Packet)
Lallemand BRY-97 (Dry - 1 Packet)

Fermentation

20C for 14 days

Carbonation

2.4 CO2-vol

Water Profile

Ca2+ (Calcium): 119
Mg2+ (Magnesium): 14
Na+ (Sodium): 19
Cl- (Chloride): 185
SO42- (Sulfate): 92
HCO3- (Bicarbonate): 43

Notes

We have taken inspiration for this recipe from David Heath's YouTube video (recipe is in the video description). We've made a couple of minor adjustments but wanted to credit David's work as we're big fans of his YouTube video's so check him out!

We've substituted David's recommended Maris Otter malt for Golden Promise - simply because we used Maris Otter recently in our El Dorado Smash so we wanted to try something different and we haven't used Golden Promise malt before.

We also reduced the amount of acid malt (sour grapes) malt that is used, simply to err on the side of caution as we haven't used this before to adjust mash PH.

Our hop varieties are also a little different, mainly because of what our local brew shop had available/in stock at the time. Any variety of juicy/fruity new world hop is going to work well with this recipe.

One of the most important aspects of a NEIPA is the water profile/chemistry - in particular the chloride and sulfate ratio. In this recipe we're using a chloride to sulfate ratio of 2:1 which is a common/popular starting point for NEIPA recipes.

We've also opted to not use a dry hop during active fermentation which is commonly used to help achieve "biotransformation" of hop oils. We figure there will be more than enough hop oils present from the large whirlpool hop addition to allow this to happen, so we're saving all of our dry hops until after fermentation is completed. We'll also use a soft crash by dropping the temperature of the fermenter to approx 15c after fermentation has completed to avoid hop creep from occurring.

Want to see how the recipe turned out? Check out our Brew Day post for this recipe or the Tasting Results and Review.


Related Articles

All Grain Recipe List

Juice Boost NEIPA - BrewZilla Brew Day

NEIPA - Recipe Creation Guide


Friday 18 March 2022

Best American Pale Ale - Tasting & Review

Review Date: 18/3/2022
Brewery Name: Birallee Beer & Brewing
Beer Name: Best American Pale Ale

After a number of weeks to mature and settle in the keg, the flavours have all mellowed and balanced out a little meaning it's time to give our latest brew the formal review treatment.

Our Best American Pale Ale in the Craftd Freddy glass

General

Alcohol By Volume (ABV): 6.0% (Standard)


Serving Style: Draft/Tap

Region of Origin: Pacific (Australia, New Zealand)

Style Family: Pale Ale

Malts/Adjuncts: Pale, Pilsner, Gladiator, Aurora

Hops: Centennial, Amarillo

IBU's: 50

Appearance

Colour: Deep Gold




Clarity

Brilliant Clear Slight Haze Hazy

Collar of Foam & Head Retention

None 

Poor
(Up to 15 secs)

Moderate
(15 - 60 secs) 

Good
(more than 60 secs)


Foam Texture

N/A Thin Fluffy Mousse-Like

Carbonation (Visible)

None Slow Medium Fast-Rising Bubbles

Alcohol Aroma

Not Detectable Mild Noticeable Strong Harsh

Aroma & Flavour

Esters Aroma: None
Phenols: None






Alcohol Taste:

Not Detectable Mild Noticeable Strong Harsh

Hop Pungency:

Mild Moderate Strong Extreme

Hop Bitterness:

Restrained Moderate Aggressive Harsh

Malt Sweetness:

Low Medium High Cloying
(Excessive)

Astringency: 

Low Medium High

Palate/Mouthfeel: 

Light Bodied
(Thin/Watery)
Medium Bodied
(Light + Full)
Full Bodied
(Round, Rich & Creamy)

Palate Carbonation: 

Low Medium High

Length/Finish:

Short
(Up to 15 seconds)
Medium
(15 to 60 seconds)
Long
(More than 60 seconds)







Oxidative/Aged Qualities: None

Overall

Drinkability: 7/10

Overall Impression: 6/10

Notes

Although by all rights this beer is pretty good, I cant help but feel a little disappointed. It just hasn't got the hop presence I was hoping/expecting it to have. In hindsight I should have dry hopped it, even just a little to get some more of those fruity hop flavours up front. This may have pushed it into IPA territory with a high IBU and ABV already, but that doesn't matter. Perhaps this is how it should be for a pale ale and my tastes have evolved to want and expect big hop presence like what is found in an IPA now?

We exceeded our efficiency expectations in the brewing process (which is good), and meant we had a beer with a higher ABV than expected. It's still balanced, but the extra alcohol really has a kick to it and is noticeable on the nose, and on the palate. Another indication that perhaps some more dry hops were required to mask it a little.

Also wondering if our process of using a hop spider in the brewing process is perhaps holding back some of the hop flavours, especially with the large and late whirlpool hop additions?

Don't get me wrong, there is definitely still some hop presence, but it's subdued or moderate at best and doesn't really shine or stand out amongst the bitterness and alcohol. It's got quite a bit of dankness on the nose, but thankfully not so much on the palate.

Mouth feel is very good - very thick, and as you can see from the photo at the top of this post, it has a nice, thick, white, "pillowy" head. Best of any brew so far and I'm attributing this to the Gladiator malt in the grain bill.

Colour wise, it's come out darker and much hazier than I expected. The colour in poor lighting conditions almost looks like it's oxidised, but it definitely isn't. And the haze is very prominent - not sure if this is from the yeast, or the hops, chill haze or some factor or combination of factors - will be interesting to see how much it clears up over time, if at all.

For 50 IBU's, it isn't over the top, as it also has the alcohol presence to back it up. It's good, but not exceptionally great. I think next time I do an American Pale I'll go with crystal malt to give it some more of those classic caramel flavours that are synonymous with the style