Saturday, January 24, 2015

American Oatmeal Brown

Salt Lake City's Epic Brewing Company (not to be confused with the brewery of the same name in New Zealand) was definitely one of the discovered gems of our three years in Utah. They specialize in high-point (Utah definition: over 4.0% ABV) beers, which state law prohibits from being served on tap. Possibly my favorite beer that they produce is their Santa Cruz Brown Ale, an American brown. This is the beer that brought me back to brown ales. I've often found the style to be overly sweet and unappealing, and a number of years ago had stopped even trying them. This example, as the name implies, takes a West Coast approach. It has the great toasty, malty, chocolatey notes one expects of
brown ales, but balances it with a drier finish and plenty of hop bitterness and aroma.

Looking to create a similar beer myself, I opted to aim a little lower in ABV, shooting for between five and six percent. Vienna was still my base grain on hand, lending more character than straight 2-row. Balancing it were moderate amounts of crystal and chocolate malts; not too much to get cloyingly sweet, but enough to add more malt structure and body. The grist also included a fair portion of oats; I've done this a few times recently and feel like it can add a little extra dimension to the beer. Accompanying this malt bill was a wallop of Amarillo and Centennial, both as a hop steep/whirlpool addition and in the dry hop. The neutral American yeast added a little bit of fruitiness but mostly stayed out of the way of the malt and hop profiles.

As Ron Pattinson might say, this beer goes down a treat. I'm almost completely out now, though I still have a bottle saved for tasting notes. This is the kind of thing I'd consider keeping on hand as my "house beer." I suspect there will be followup batches in the not-too-distant future.

One more thing... I've made another step into joining the twenty-first century social media community by opening an Instagram account. In typical beer nerd(/hipster? I can't conceive of myself as hip) fashion, it's essentially a rundown of beers I'm drinking with quick tasting notes. Lots of sexy shots of our collection of Funkwerks goblets, guaranteed. For those who are interested, here's me: @bier_here.

American Oatmeal Brown

Batch size: 5 gallons
Projected OG: 1.054
Projected SRM: 20.2
Projected IBU: ~48.1(whirlpool/steep hops as 15 min)

Boil time: 60 minutes
Brewhouse efficiency: 75%

Grains
76.1% - 8 lb Weyermann Organic Vienna

9.5% - 1 lb Flaked Oats
4.8% - .5 lb C40
4.8% - .5 lb C60
4.8% - .5 lb American Chocolate


Hops
.5 oz Magnum (13.5%) (60 min)
1 oz Amarillo (8.2%) (0 min) - 30 min steep
1 oz Centennial (11.8%) (0 min) - 30 min steep

2 oz Amarillo (Dry hop - 5 days)
1 oz Centennial (Dry hop - 5 days)


Yeast
US-05 (repitch from Summer Farewell Blonde)


Water
Profile: Reno
1 g Gypsum
1 g Epsom salts 1 g CaCl
1 g CaCO3


Brewday: 21 October 2014
Mash: 154F for 60 minutes

Pre-boil volume: 6.9 gallons
Pre-boil SG: 11.2P (1.045)

Fermented in swamp cooler at 64-66F.

Active fermentation done after about 5 days. Bumped up to 70F & swirled to make sure it completes any unfinished business.

Secondary: 6 November 2014
FG: 1.012
ABV: 5.5%


Bottled: 11 November 2014
Bottled with 4.6 oz of brown sugar.

Tasting: 16 February 2015
Some pine is present, but as this beer warms a little, the biggest sensory impression I get--other than hoppy--is chocolate covered orange. Fantastic.

Monday, January 19, 2015

5-Year Tasting: Mad Elf Clone

While my parents were in town before Christmas, my father and I split the second-oldest homebrew I still have: the final bottle of my Troeg's Mad Elf clone. This beer at a year old was really spectacular; the alcohol harshness had mellowed, and the cherry character came through beautifully.

Unfortunately the ensuing years and treatment have not been kind to this bottle: at five years old, it had given up the ghost. While I could be disappointed, I'm instead spurred to continue my aging program. In addition, this beer definitely deserves a rebrew; it's a recipe that really shines with some age on it.

=====

Date: 16 December 2014

Venue: Our house (Sparks, NV)

Appearance - Cloudy red-brown. No head; thin lacing around the edges of the glass.

Smell - Sweet cherry, slight alcohol.

Taste - Belgian yeast peppery quality on the back of the tongue, which sits for just a few seconds before disappearing. The cherry from the aroma, which was my favorite element from the last tasting several years ago, doesn't carry through here. Its absence leaves nothing to balance the current tannic roughness and alcohol bitterness that follow the pepper note. The bottom has kind of fallen out, the Belgian yeast character becoming quite harsh.

Mouthfeel - Carbonation is still prickly, showing the bottle has held pressure well. The beer has a certain creaminess.

Overall - Disappointingly, this beer is well past its prime. We couldn't even bring ourselves to finishing the glasses we'd poured. It was a good experiment, though, and definitely worth it.

Wednesday, December 3, 2014

Brett/Bug Culturing


I keep going back to the Mad Fermentationist for inspiration. A couple months ago I listened to Jay Goodwin of the Rare Barrel interview Mr. Tonsmiere himself about his new book (which I'm sorry to say I still haven't read) on the first episode of the Brewing Network's Sour Hour. It sent me to the MF blog archives, particularly to a post from a few years back on maintaining Brett and Lacto cultures. My sour brewing has gone all right so far, but I'm interested in doing more, so I decided to take some advice from that blog post and start a mixed microbe culture.

Since I'm looking to nurture the full range of tasty sour bugs available, I made a quart of starter wort from a mix of DME and preservative-free apple juice to an OG of about 1.030, along with a bit of yeast nutrient. This is hanging out in a growler in the back of our fridge to keep the bacteria from outcompeting the yeast. Every other month I'll decant off the old starter and add a new batch. I may add a few IBUs worth of hops to successive worts and sample the fermented starters to get a sense of the culture's evolving character (and make sure it hasn't gone south).

Now when I have a sour beer at home that I enjoy, I check this list of viable bottle dregs (once again from MF, natch). If it's on there--or I can find decently reliable information elsewhere that the bottle should contain living bugs and/or Brett--I flame the bottle lip and the dregs go into the growler. It's definitely influenced my beer-buying habits; I purchase sours more often now, but also spend time investigating them for possible culture viability.

As long as this culture continues to behave itself, I'll keep a record of its development here, including the list of dregs added and when I change out the starter wort. The initial donors are in the picture above, and I just picked up a few more bottles last week in Colorado that will make their way into the mix soon. I'm sure that eventually I'll acquire a few samples from the burgeoning northern California sour scene as well. Let me know if you recommend scouting out anything in particular!

Sour Culture No. 1

11 October 2014:
Added 1 qt starter wort @ ~1.030 (Light DME, Apple juice, Yeast nutrient)

2012 Goose Island Sofie
2012 Lindemanns Cuvée René

7 December 2014
Decanted off old starter wort
Added 1 qt starter wort
   .5 qt Apple juice
   2 oz DME
   No hops this time
OG: 14.6P (1.059)! Way higher than desired. Added extra 1 qt water to bring it in line.

Old starter tasted pretty sweet. The cold is impeding the bugs from out competing the Sacch & Brett, but all microbial action may be near zero at this point. Considering giving the starter a warm stretch at some point in the process to ensure everything stays alive & working.

13 January 2015
2014 TRiNiTY Blow Up Your TV Blanche Saison Grisette

14 January 2015
2014 Crooked Stave St Bretta Autumn

18 February 2015
Warmed starter to ambient (high 50s) a few days ago; subdued but active fermentation in progress. Kicking out sour, buttery aromas presently.

30 March 2015
Decanted off old starter wort. Sat out at ambient (~65F) for a few weeks, then back into the fridge once active fermentation ceased.
Added 1L starter wort
   1.1 L Filtered water
   55 g Light DME
   Pinch Yeast nutrient
   No hops
100 mL went on to 2015 Russian River Damnation dregs; rest onto bugs. Both starters out on counter, ambient ~65F.

Old starter was tart, clean, and very tasty. Guess we'll see what develops in a full-size, long-term ferment.

///

Sour Culture No. 2

21 October 2015
1 qt starter wort @ ~1.030 (light DME, yeast nutrient)
Kept on counter at ambient temp (~67F)

2015 Almanac Farm to Table Farmer's Reserve Pluot
   - Hay/tart aroma; rounded fruity (pluot) taste

23 October 2015
2015 Bruery Terreux Sour in the Rye
   - Firm lactic acidity

22 December 2015
2015 Crooked Stave Hop Savant Galaxy
   - Musty funk, light citrus, hay

24 December 2015
2015 Crooked Stave Progenitor
   - Barnyard, hay, tropical funk

3 January 2016
Dec 2014 Crooked Stave Cerveza Sin Frontera
   - Drying sour, lots of cranberry

17 January 2016
Chilled in fridge for a week and a half, decanted beer. Beer was nicely tart, fruity, background saltine note (Crooked Stave character) with a surprisingly viscous mouthfeel.
Added .75 qt boiled down final runnings from IIPA.

///

Sour Culture No. 3

26 May 2016
10 g DME in 100 ml water, plus a pinch of yeast nutrient
Oct 2014 Logsdon Farmhouse Cerasus
   - Complex tart (lactic & acetic), cherry, oak tannin, a little malt

31 May 2016
2015 Cascade Blackcap Raspberry
   - Really nice dark berry, solidly sour

7 June 2016
100 g DME in 1 L water, plus a pinch of yeast nutrient

16 June 2016
Chilled in fridge for several days, decanted beer. Not fully attenuated--only left a few days for fermenting--but resulting beer was lightly tart and had a really nice strawberry flavor.

///

Sour Culture No. 4

20 November 2016
4 oz DME in 500 ml water, plus a pinch of yeast nutrient
2015 Russian River Supplication
   - Hay, barnyard, cherry, Pinot, damp funk, oak

23 November 2016
2016 Holy Mountain Grapefruit Table
   - Clean lactic acidity (lemon), grapefruit juice

27 November 2016
2016 Holy Mountain Dark Retreat
   - Strong, rounded tart (not just lactic), juicy red/dark berry, oak

4 December 2016
2015-16 Oude Gueze Tilquin A l'ancienne
    - Wet hay, lemon peel, damp basement, tannic

25 December 2016
Chilled for a week, decanted & added 52 g DME in 500 ml water, plus a pinch of yeast nutrient. Spent starter was sweet-tart with a prominent Cheerios flavor that dominated the aftertaste (THP).

26 February 2017
Chilled for several days, decanted & added new starter (1.5 oz DME in .5 qt water plus yeast nutrient). THP was very prominent, the principal flavor of the spent starter, followed by a faint tartness.

16 April 2017
Chilled for several days, decanted & added final runnings from an IPA. Much less grainy/cheerios, now only faint; stronger tartness that grips the back of the throat a bit. Still a keeper.

6 May 2017
Holy Mountain The Gray Tower Blend #3
    - Mandarin orange tart, deep damp funk

///

Sour Culture No. 5

25 December 2016
50 g DME in 500ml water, plus a pinch of yeast nutrient
2016 Cascade Blackcap Raspberry
   - Strong lactic tartness, big dark berry, jammy, fantastic

30 December 2016
2016 Logsdon Farms Cerasus
   - Tart cherry, woody, drying, very slight Cheerios at end

26 February 2017
Chilled for several days, decanted & added new starter (1.5 oz DME in .5 qt water plus yeast nutrient). Spent starter was clean, weakly lactic tart, watery, a touch cherry.

16 April 2017
Chilled for several days, decanted & added final runnings from an IPA. Clean, solid tartness, still a good bit of cherry/berry.

17 June 2017
Chilled, decanted & added new starter (2 oz DME in .5 qt water plut yeast nutrient). Still pretty cleanly tart with a fair berry note, maybe a hint of graininess/Cheerios sneaking in. Next week, while it's hopefully very active, it will go into sour beer that will eventually get a bunch of stone fruit.

Saturday, November 15, 2014

Amarillo Rye Saison

I've mentioned before that I have a messy history brewing saisons; I've often tried to use the style as a forum for weirdness before really figuring out the base beer. This summer's straightforward iteration was much more successful, though it may have suffered from some oxidation in the bottle. For my second batch of Reno-based homebrew, I continued my exploration of this fascinating, rustic beer.

The biggest influences on wort production were 1) the significant amount of Weyermann rye malt in my stores right now, and 2) an astonishingly good deal on Amarillo pellets at Reno Homebrewer, one of the local supply shops, right after we moved here. I've stuck with Wyeast's French Saison yeast over one of the Dupont strains. Dupont isn't my favourite example of the style and I really like how WY3711 tears right through a wort without fuss.

As an added bonus, it was on this batch that I finally checked the efficacy of my water bath method for stabilizing fermentation temperature. I've never been sure of the temperature differential between the water bath and what's going on in the fermenter during active fermentation. Thus, I didn't really know how much I
needed to drop the water bath temp to maintain my target fermentation temp. With the saison wort actively fermenting (just about high krauesen) in a glass carboy sitting in a ice chest water bath that only came halfway up the batch, the fermentation only ran a half a degree higher than the water bath itself. I'll definitely do more testing, but that's an informative first result.

The beer finished nice and dry--as expected with this yeast--and has been in the bottle for a few weeks now. As beer tends to do, it's evolved a bit over that time. Early on, the leading aromatic and flavour character was somewhat phenol-plastic; it wasn't terrible, but it definitely wasn't the best. That's begun to mellow a little, leaving room for a fruitier character to come through. My initial impression is that the Amarillo and rye (even at 30% of the grist) are not playing dominant roles; it's the yeast that still comes to the fore (see update below). If anything, some of the unpleasantness may have come from the interaction of these ingredients. It may be on the bright side for the cooling fall temperatures, but it helps me remember summer. Complete tasting notes coming soon.

My next saison will be a rebrew of my petit saison noir from a few winters ago, hopefully with the WLP566 I originally used. I don't really have any "house" yeast strains, especially for saisons, though I've really been pulling to get what I want out of WY3711. Based on this current batch, though, I may start to mess around with others to find my preferred mix of fermentation characters. Of course, if this beer continues to mature into something along the lines of my last saison, I may just stay put.

Update: It's hard to keep everything in mind all the time. As I'm sure many of you have, I now recall reading a pile of anecdotal information on the plastic-phenol bombs that can arise when combining Belgian yeasts with American hops. I'd forgotten all about that until yesterday, when I watched Nate Smith's 2014 NHC presentation on using new hop varieties, courtesy of the intrepid Chip Walton of Chop & Brew. I'm considering rebrewing this beer soon with more traditional continental hops--either Styrian Goldings or something noble--to contrast with the current batch and possibly restore my faith in WY3711.

On another note, I really like the concept Nate presented in his talk for doing split batches to compare hops. He produces a large batch (15 gallons) of base wort, then splits it post-boil, running 5 gallons at a time through a hop back with a different hop variety, then through a plate chiller to each fermenter. He then usually follows up with a dry hop that matches the hop back charge for each split. It's a great idea that easily scales for smaller test batches, but requires a couple pieces of equipment I lack. Worth ruminating on for the future...

Update 2: After some time in the bottle, this beer has really turned around for me. While the combination of Amarillo and spicy yeast still throws me a little, the plastic character is gone. Much more drinkable, thankfully! Notes on this beer and the rebrew coming soon.

Autumn Denial - Amarillo Rye Saison

Batch size: 4.5 gallons
Projected OG: 1.063
Projected SRM: 7.3
Projected IBU: 30.1
Boil time: 60 minutes
Brewhouse efficiency: 79%

Grains/Fermentables
60.0% - 6 lb Weyermann Organic Vienna
30.0% - 3 lb Weyermann Rye
10.0% - 1 lb Turbinado (10 min)

Hops
.5 oz Millennium (13.5%) (60 min)
.5 oz Amarillo (8.2%) (10 min)
1.5 oz Amarillo (dry hop - 5 days)

Yeast
WY3711 French Saison - 1.5L stirplate starter

Extras
1 tsp Yeast nutrient (10 min)

Water
Profile: Reno
1 g Gypsum
1 g CaCl
1 mL Lactic acid (88%)

Brewday: 27 September 2014
Mash: 12 qts @ 147F for 3 hours - dropped to 116F
Pre-boil volume: 6 gallons
Pre-boil SG (w/o turbinado): 11P (1.044)

Chilled to 74F. Yeast pitched a little over 24 hours after knockout, once starter flocc’d out. Aerated for 30 minutes before pitching.
Fermented in swamp cooler at 70F for 2 days, then raised 3F/day to 80F.

Dry hops: 14 October 2014
Added loose to primary.

Bottled: 20 October 2014
FG: 1.003
ABV: 7.9%
Bottled with 4.8 oz brown sugar.

Friday, November 7, 2014

Blonde Ale

Properly situated in our new digs, it was a happy day when the brewing kit finally came out. The first beer on the docket was a style that hadn't held much interest for me until recently. I've often passed over blonde ales for bolder, hoppier options like pale ales and IPAs. As I've cultivated an appreciation for the uncluttered flavours of pilsener and kolsch over the past year, though, blondes have found a place in my glass, prized for their bready notes and extreme drinkability. I'd hoped to brew this before the official change in season--this would definitely count as a lawnmower beer--but with the weather here still more summery than autumnal on brewday, it worked out just fine.

A blend of domestic 2-row and Vienna keep the colour light. I haven't used Palisade hops before, but the descriptors--floral, subtle apricot, grassy--are in line with the unobtrusive role they're set to play here. I've wanted to see how a single yeast strain behaves over successive batches for a while now, so the neutral Chico yeast seemed like it would serve the purposes of that experiment and this beer.

For the first product of the brewhouse's new location, this was definitely a success. It might actually be too restrained, but it has a long bready tail and is still pretty damned quaffable. It's a fast, easy, sessionable beer that's kept the fridge well stocked and helped us make new friends; it'd make a great house ale that would easily lend itself to experimentation. I imagine I might see this one again (or a variation of it) come next spring.

Summer Farewell

Batch size: 6 gallons
Projected OG: 1.044
Projected SRM: 3.5
Projected IBU: 16.9
Boil time: 60 minutes
Brewhouse efficiency: 91%

Grains
62.5% - 5 lb Malteurop 2-row
37.5% - 3 lb Weyermann Organic Vienna

Hops
.5 oz Palisade (7.8%) (60 min)
.5 oz Palisade (10 min)

Yeast
11.5 g US-05 (rehydrated)

Extras
1 tsp Yeast nutrient (0 min)

Water
Profile: Reno
1 g Epsom salts
1 g CaCl
1 mL Lactic acid (88%)

Brewday: 27 September 2014
Mash: 10 qts @ 154F for 105 minutes - dropped to 144F
1st sparge: 11 qts @ 212F (w/ .75 mL Lactic acid)
2nd sparge: 11 qts @ 190F (w/ .75 mL Lactic acid)
Pre-boil volume: 6.7 gallons
Pre-boil SG: 9.2P (1.037)

Chilled to 68F.
Fermented in swamp cooler at 62F.

4 October 2014: Activity slowed. Removed from swamp cooler & swirled a few times a day.

Bottled: 7 October 2014
FG: 1.008
ABV: 4.7%
Bottled with 5.1 oz table sugar.

Tasting: Three and a half months after brewing, it showed its age a bit...or perhaps just my poor handling later in the process. The good bottles were still crisp, crackery, and very drinkable.

Wednesday, October 1, 2014

Peach Melomel II

It took some time to get my brewing kit set up here, but this past weekend I finally snuck some wort into a couple fermentors. In the meantime, though, we came across the perfect excuses to engage in some gluten-free fermentation: ripe California peaches at the farmers market and a closeout on a brand of honey at the local Whole Foods.

Reno is host to a different farmers market just about every day of the week during the summer. Much of the selection comes from across the state border, and these markets are overflowing with tomatoes, peppers, strawberries, seafood, and more. DeAunn discovered freestone peaches from one of these vendors that were nearly as good as the ones we had in Alabama a couple summers ago. Recalling how well our first melomel turned out using those southern peaches--we enjoyed the final bottle to celebrate our move here, and it was excellent--it took little time to plan this followup. Finding a frankly fantastic deal on honey only made it come together more easily.

The recipe remained the same from the previous batch, though the ratio of fruit to honey was switched in favour of the honey, due to the weight of the peaches once we got them home and prepped. Our new place provided a more stable fermentation environment than the last batch had; that one toiled away on the rear floorboard of our car as we drove cross country in the middle of summer. Michael Tonsmiere raised an excellent point this spring on considering honey varietals (his first line puts it best: "If a beer recipe calls for 'honey' without specifying a varietal, it might as well call for 'malt' and 'hops' with similar imprecision."). I'd very much like to explore more fully the fermented outcomes of different types of honey available. For now, though, the general "wildflower" honey I've found works just fine, fermenting clean and leaving a fragrant white wine-like note.

As I prepared to transfer this melomel over the weekend, I was dismayed to open the fermentor and find two fruit flies floating on the surface. I've played it pretty fast and loose with mead; since we usually aim to make about 1.5 gallons per batch, I've done all of my primary fermentations in the two-gallon bucket we bought for that first batch of melomel. I left the lid, now quite warped, loose and covered the bucket with a clean t-shirt, relying on this setup to be enough to keep away any nasties. Obviously it wasn't enough this time, and the batch may suffer for it. The bucket has now gone for recycling; next time, we'll go with primary in glass.

The mead has now been racked to secondary on bentonite to clear, and a half gallon received newly-toasted oak cubes as well. It had fermented quite dry, and showed no signs of infection at that point. It's dropped pretty bright already, so we'll plan to bottle soon, keep it cold, and drink it quickly. Hopefully we'll be able to avoid the majority of possible bacterial off-flavours and fully enjoy this reminder of our first taste of our new home.

Peach Melomel II - Reno edition
Batch size: 1.75 gallons
Projected OG: 1.121

Fermentables
5 lb 12 oz Honey
3 lb Peaches - peeled, sliced, frozen

Yeast
Lalvin 71B-1122

Extras - SNA
1 tsp Yeast nutrient
.5 tsp Yeast energizer
   3/8 tsp after pitching
   3/8 tsp after 24 hours
   3/8 tsp after 48 hours
   3/8 tsp after 72 hours

Brewday: 1 September 2014
Fermented at 75F ambient.

Secondary: 28 September 2014
Added 1 tsp bentonite dissolved in 1 cup water, .5 oz newly-toasted oak to .5 gallon.
Found two fruit flies in the bucket. Apparently I didn’t keep the bucket covered well enough...

Saturday, September 27, 2014

2014 Beehive Brewoff Results

We're just about settled in our new place in Reno. Helping this feel more like home, I put together a melomel a few weeks ago, which I'll move out of primary for clarification and further aging today. Today will also mark my first brewday in Nevada, an event that will definitely help me feel more at home here. The first bit of homebrewing activity here, however, came a few weeks ago in the form of my BJCP scoresheets from the 2014 Beehive Brewoff.

This was my second time entering this competition, and I felt the feedback I received both times was on the mark for the beers reviewed. I'm happy to report that this year the Belgian dark strong I brewed a couple years ago took second in the Belgian strong ale category with a respectable average score of 40. The years have treated this beer well, rounding off its sharp edges. It's gratifying as well as edifying to read reviews from impartial judges; even though they scored this beer well, they had suggestions for improving it.

Even more helpful were the scoresheets for the other two beers I entered, my second attempt at a Flanders red and my most recent iteration of Russian imperial stout. The RIS scored a 32, dinged primarily for high residual sweetness and astringency. The FG was quite high in the end, which I'd hoped would help balance the high amount of roasted grains (the main contributor of astingency). In the end, I missed the balance here; while I enjoyed the experiment of cutting out the caramel malts and upping the roasted component on this batch, it does make for a less pleasurable experience than it could be. I'll definitely retool for the next go-around, adding back some caramel and cutting down on the roast.

The Flanders red did not do well, scoring an average of 22. While it received generally good notes for the aroma, the judges pointed to a high level of acetobacter activity (vinegar) and high astringency. While they found it to be sour, they found little else. At the beginning of the summer, in the first few months after bottling, I got a ton of great cherry and bready malt riding the bracing wave of sourness in this beer. Tasting it now, however, I certainly agree with the judges; most of the cherry and malt have fallen off, leaving just a stomach-churning acidic burn. However, I think I've already had more mileage out of this batch than I could have reasonably expected: it blew out its airlock in primary over the summer while we were away for three months, then spent a year wasting away in a plastic bucket, prone to oxygen exposure and acetobacter infection, before I finally bottled it. That I was able to have a good tasting experience with this beer at all was a boon, given the amount of abuse and mishandling it received.

Though we're not in Salt Lake City anymore, I would not hesitate to enter this competition again. Furthermore, I plan to seek out competitions locally over the next few years; getting experienced opinions from others on how to improve my beers will certainly help me advance more quickly than just doing my own informal evaluations. Looking forward to brewing today, and improving those beers in subsequent batches.