There are many beers hitting the market with various fruit additions, of which Ballast Point's fruit variants are the poster child, but they are hardly alone. It got me wondering what if anything is significantly different about brewing commercially with high amounts of fruit. I know that brewer's yeast converts most sugars in alcohol, but it works better on some sugars (like maltose, sucrose, etc.) than others (like lactose). Where does fructose, the main sugar type in fruit, fall on the beer fermentables scale? How does a high amount of fructose effect fermentation of the beer and/or the end product? Do brewers have to account for anything significantly different in the brewing process with high amounts of fruit? Does brewing a beer with these fruit additions often run into the same issue as simple sugar additions (e.g. honey, candi sugar, corn/rice syrup, etc.) where the sugars primarily increase ABV without imparting much flavor? It just occurred to me that maybe using concentrated fruit essences could bypass these issues with fermentation. Is that what most/some brewers do? I'm not a homebrewer so some of my questions may be silly, but I am generally just curious what if anything is different brewing with fruit on a commercial scale. Tagging a few people I think might be helpful: @Sixpoint @hopfenunmaltz @JackHorzempa @bulletrain76 Thanks in advance!
Randy, I am not a brewing with fruit expert. So far the only fruit I have brewed with is cranberry for my Cranberry Belgian Pale Ale. For that batch of beer I use Cranberry Juice; 1 quart of 100% Cranberry Juice for a 5 gallon batch. I add the juice to the primary after fermentation is complete. Cranberries do not have a big fruit flavor, they primarily add a bit of tartness to the beer. There is very little sugar in cranberries. My wife once requested I brew a Peach Wheat once but frankly I balked at brewing that beer. I did read a bit and the recipes I saw required that you create a puree out of the peaches and place them in a secondary where you would add the fermented beer. Since peaches do have a fair bit of sugar there would be a second fermentation occurring where the yeast would process those sugars. Peaches (or you could actually use Apricots for this particular beer) do have a distinctive flavor which will be quite noticeable in the resulting beer. I had a Grapefruit Tripel at last year’s National Homebrewers Conference that I thought was fantastic so I am currently contemplating brewing a beer like that. I would solely be using the zest of the grapefruits in brewing this beer. So there will be no sugars involved; just the flavors from the grapefruit peel. Hopefully the other folks you tagged will provide some input here. Cheers! Jack Edit: Maybe @LeRose can share some thoughts here.
When you think about fructose, look no further than wine. I brewed a Peach Pale Ale once and the alcohol content went way up from using a pound of frozen pureed Peaches. What you have to be careful with when brewing with fruits is the Pectins, which usually come from the skin of the fruit.
Sucrose is a glucose and fructose bonded together. All of those are highly fermentable. Wort has about 2% fructose as a percentage of sugars and dextrins content.
Fructose is fully fermentable. When sucrose is present the enzyme invertase present in yeast converts it into equal amounts of glucose and fructose. Sucrose is of course fully fermentable.
I recall reading something about and when yeast utilize different sugars during the life cycle...it was hellaciously complicated and of course I can't find it (or secretly don't want to). The takeaway was that the yeast use different sugars at different times. This tidbit from Wyeast web site sort of sums it up, but the bottom line is there are stages to fermentation that eventually use up different sugars somewhat preferentially. Sucrose plus the enzyme invertase makes 50/50 glucose and fructose, both of which are completely fermentable, as is the sucrose. But I do recall there is something of a pecking order, if you will. Where Do Yeasts Come From? Yeasts are everywhere! There are several hundred recognized species of yeasts, with many strains within each species classification. Basically, anywhere there is a carbohydrate (sugar) source, you will probably find yeasts that are adapted to consume it. Saccharomyces cerevisiae is a species that has the capability of utilizing a wide range of sugars such as, glucose, fructose, mannose, galactose, sucrose, maltose, maltotriose, and raffinose (lager yeasts can also metabolize melibiose). The ability to metabolize a wide range of sugars allows Saccharomyces cerevisiae adapt to many environments. There are calculators for fermentable sugar contribution from fruit, so a brewer can estimate the "total fermentable sugars" in the process. This article from MoreBeer is helpful, I think, and gives a general idea of how much sugar is in some common fruits. There's a lot of guesswork and assumptions in the article (like recovery of sugars from the fruit) so at best this shows a semi-educated estimate: https://www.morebeer.com/articles/fruit_in_beer So the contribution of fermentable sugars from non-malt sources can be at least estimated. If you know your process and know how much sugar you are actually extracting from the fruit rather than making a SWAG assumption on yield, I'd think you'd be able to calculate reasonably well. Then I assume that the grain bill would/could be adjusted and you could keep your total fermentables the same. You also get other stuff from real fruit (like pectin), but that's another topic. But it still says nothing about the flavor impact (ie, how many peaches are needed to generate a strong peach flavor vs just providing sugar to jack up the ABV). Making a puree of fruit or at least macerating it some will increase the availability of the sugars and generate more flavor versus stuffing them in whole. I know Allagash cuts peaches in half for their barrel-aged peach. Harpoon adds real juice to their grapefruit UFO, but after fermentation and they pasteurize the blend. Whatever fruit (or juice/concentrate or puree) is added will contribute fermentable sugars - even cranberries (@JackHorzempa - we've discussed this at length). I think of it like dried vs. fresh herbs - fresh herbs are great, but you need way more of them to get the same flavor as dried. It probably takes more fresh fruit than you think to impart flavor to a batch of brew. Flavorings - from my non-beer experience with them there are crap flavors and their are outstanding flavors available. Like speed in a race car, it's pretty much a question of money. The best flavors are the most expensive by far. There are also some regulatory issues involved - at least in non-alcoholic beverages. Back in the day, we had an entire department just working on "flavor development" because the results aren't always what you'd expect. Here's an example (and I have to be a little careful what I say here) - we have two flavors from two very reputable suppliers. Neither of them separately is reminiscent of the particular fruit we want, but when you combine them and work on the overall beverage formula, they actually do boost the fruit flavor and since there's no sugars or acids, we don't have to make huge formula corrections. Just not by themselves. Heck, we collect cranberry "essence" every day from our fruit process and it doesn't taste or smell one bit like a cranberry - by itself, it doesn't represent the fruit as illogical as that sounds. sometimes it does - the citrus and tropical fruit oils and aromas do. Others seem to need some synergies. OK...I'm talking too much again...short version. Yes - you could get there by using flavorings (essences, aromas, essential oils, etc) versus the real fruit, but it might take quite a bit of work to come up with the right blend of flavorings and figure out how to use them judiciously. I imagine some are doing just this - using a flavor to achieve the taste without worrying about the fermentation or aging on fruit processes. The brewers where I know the process with some certainty are not - they are using real fruit or fruit juices/concentrates.
While fructose is 100% fermentable, many brewers doing "Fruit IPAs" nowadays are simply brewing a regular IPA, then dosing the beer with a fruit extract or fruit essence after fermentation is complete. Sometimes this extract/flavoring is even high-fructose corn syrup based, resulting in a sweeter flavor. Therefore, the "fruit" is mostly a non-factor in regards to the ABV, and is added after all fermentation is complete.
Larry (@LeRose) it is my understanding that Ballast Point is using some sort of grapefruit ‘product’ for brewing Grapefruit Sculpin since the labeling states “…with natural grapefruit flavors”. Do you have any speculation on what exactly Ballast Point is using to brew this brand of beer? Cheers!
I wonder what the regulations are for beer and spirits? In a juice type product, this would not be a flavor from a juice or concentrate. It would be natural flavors (oils, essence, aroma, emulsion, etc) derived from citrus. Does beer follow the CFR for this kind of thing? From CFR 21: 3) The term natural flavor or natural flavoring means the essential oil, oleoresin, essence or extractive, protein hydrolysate, distillate, or any product of roasting, heating or enzymolysis, which contains the flavoring constituents derived from a spice, fruit or fruit juice, vegetable or vegetable juice, edible yeast, herb, bark, bud, root, leaf or similar plant material, meat, seafood, poultry, eggs, dairy products, or fermentation products thereof, whose significant function in food is flavoring rather than nutritional. Natural flavors include the natural essence or extractives obtained from plants listed in 182.10, 182.20, 182.40, and 182.50 and part 184 of this chapter, and the substances listed in 172.510 of this chapter. Source: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/cfrsearch.cfm?fr=101.22 Besides, if it had grapefruit juice in it, it would be cloudy as any "juice bomb East coast IPA". Clarified grapefruit juice doesn't taste like grapefruit juice - trust me
The yeast will go after the simple sugars first, then the more complex. It is said if they have too much simple sugar first they can then "get lazy" and not work on the the higher sugars. That being said, beers such as Belgian Tripel has 20% of the fermentable added as sugar. Where that limit is, I don't know.
I looked into this extensively from a homebrew perspective last summer. I brewed a wheat beer, let it ferment for a week, then added the juice from two honeydew melons. Fructose is highly fermentable but the amount of water that makes up the juice basically equaled out the ABV. The beer was a hit!
Warning...threadjack follows, but in the interest of science... I remember reading about the yeast getting lazy and that there is a preferential order in which sugars are utilized. This article by Palmer states it clearly and also indicates that the little critters will quit when over-supplied with monosaccharides. This isnt the highly technical paper, and I recall now that the discussion was about ester production, but it does point out there is a preferential order of fermentation. I save everything...doesnt mean I can find it whenI want it It also points out thatthe complex sugars need to get broken down into simple sugars before they are fermented. It is also interesting that sucrose is enzymatically broken down outside the cell, yet maltose and maltotriose are brought into the cell, then cleaved enzymatically. Sweetness
I have read that some pathway gets shut off if they have to much simple sugar. One guy I know said that can take a while and not to worry, he was working on a microbiology PhD studying yeast. As I said above, you can go to 20% sucrose in a high gravity Tripel and the yeast don't seem to suffer from it, they can keep going (that is for Belgain yeast, others might not be able to finish).
