Potassium Metabisulfite - required?

[wildhair]

I recently had an issue getting a batch of rhubarb wine started. It took well over a week. The temp of the must was in the upper 60's F at the start, sg was 1.092 and the ph was 3.2 . Over the course of a week - I had to warm the must up to about 80 F and pitched yeast 3 times before I saw any activity. 3rd time was a charm and it finally took off. The first yeast packet was a bit old, but #2 (EC-1118) & 3 (SN9) were new.

I had the rhubarb loose with only the sugar, peptic enzyme and water + 1/16 t of potassium metabisulfate per gal or a total of 3 ~ 1/8t for the 6 gal batch.

Since I only had to add about 2 gal of water to the 22.5 # of rhubarb to get 6 gal of juice - it got me wondering - had I added too much pot meta and THAT'S what kept the fermentation from starting?

The purpose of the Campden tabs or kmeta is to kill any wild yeast on the fruit, so if the fruit I use to make the must has been frozen for 9 months or so - aren't the wild yeasts already dead? Do I need to add Campden tablets or kmeta if I'm using frozen fruit?

I also usually add the peptic enzyme at least 12 hrs. AFTER the pot meta, but I added it at the same time in this batch - to help draw the juice from the rhubarb. Could the peptic enzyme have inhibited the yeast growth for a week?

Appreciate thoughts and experienced input.

 

[Johnd]

I recently had an issue getting a batch of rhubarb wine started. It took well over a week. The temp of the must was in the upper 60's F at the start, sg was 1.092 and the ph was 3.2 . Over the course of a week - I had to warm the must up to about 80 F and pitched yeast 3 times before I saw any activity. 3rd time was a charm and it finally took off. The first yeast packet was a bit old, but #2 (EC-1118) & 3 (SN9) were new.

I had the rhubarb loose with only the sugar, peptic enzyme and water + 1/16 t of potassium metabisulfate per gal or a total of 3 ~ 1/8t for the 6 gal batch.

Since I only had to add about 2 gal of water to the 22.5 # of rhubarb to get 6 gal of juice - it got me wondering - had I added too much pot meta and THAT'S what kept the fermentation from starting?

The purpose of the Campden tabs or kmeta is to kill any wild yeast on the fruit, so if the fruit I use to make the must has been frozen for 9 months or so - aren't the wild yeasts already dead? Do I need to add Campden tablets or kmeta if I'm using frozen fruit?

I also usually add the peptic enzyme at least 12 hrs. AFTER the pot meta, but I added it at the same time in this batch - to help draw the juice from the rhubarb. Could the peptic enzyme have inhibited the yeast growth for a week?

Appreciate thoughts and experienced input.

The heart of your issue getting your yeast started, was that you used entirely too much sulfite. The normal dosage for inhibiting wild microbial action in your must prior to pitching, is 1/4 tsp per 6 gallons, you used 3-1/8 tsps, way too much. That's why it took so long for the yeast to get going, the levels of sulfite had to dissipate. Next time, if you feel the need to use sulfite prior to yeast pitch, use it at the rate of 1/4 tsp / 6 gallons, and let it sit 24 hours prior to pitching your yeast.

Personally, with frozen fruit/veggies that don't have some issue like mold or rotten spots, I wouldn't feel the need to use it at all, but that's my personal preference.

 

[wildhair]

The heart of your issue getting your yeast started, was that you used entirely too much sulfite. The normal dosage for inhibiting wild microbial action in your must prior to pitching, is 1/4 tsp per 6 gallons, you used 3-1/8 tsps, way too much. That's why it took so long for the yeast to get going, the levels of sulfite had to dissipate. Next time, if you feel the need to use sulfite prior to yeast pitch, use it at the rate of 1/4 tsp / 6 gallons, and let it sit 24 hours prior to pitching your yeast.

Personally, with frozen fruit/veggies that don't have some issue like mold or rotten spots, I wouldn't feel the need to use it at all, but that's my personal preference.

Just so we are clear on the quantity of kmeta (in case I didn't put it down right) - I added 1/16t X 6 =1/8 t X 3. That ratio is 1/4 t : 4 gal - that's only 1/8 t more than you recommend in 6+ gal. All the reference I have says 1/16t : gal was the correct amount. But it's good to know I can go lighter on the k-meta.

I was wondering if I could omit it entirely if the fruit is frozen - but use it if there are some funky spots. Thanks for your opinion.

 

[Johnd]

Just so we are clear on the quantity of kmeta (in case I didn't put it down right) - I added 1/16t X 6 =1/8 t X 3. That ratio is 1/4 t : 4 gal - that's only 1/8 t more than you recommend in 6+ gal. All the reference I have says 1/16t : gal was the correct amount. But it's good to know I can go lighter on the k-meta.

I was wondering if I could omit it entirely if the fruit is frozen - but use it if there are some funky spots. Thanks for your opinion.

Sorry, I mis-read what you typed, I thought you put in 3-1/8 tsps, not that you put in 3 each 1/8 tsp doses. Your thought that the dosage may have been on the high side due to only having to add 2 gallons of water has merit, that could elevate the levels enough to slow it down. Perhaps it was the combo of a little high on the sulfite, lowish temps and the first packet being on the old side that slowed down the startup, glad to hear it's chugging along now. To my knowledge, pectic enzyme doesn't have any effect on the yeast getting going.

 

[Rice_Guy]

Freezing does not kill yeast, ex. most store bakery bread is factory frozen at proofing and recovers when thawed at the store. also, Your total micro count will not change because it was frozen.
Pectic enzyme will not inhibit yeast, it’s function is to cleave pectin and prevent gel formation, , , FYI, , I don’t use pectase enzyme with rhurbarb, since it clears quite well, I also freeze to help extract juice.

The purpose of the Campden tabs or kmeta is to kill any wild yeast on the fruit, so if the fruit I use to make the must has been frozen for 9 months or so - aren't the wild yeasts already dead? Do I need to add Campden tablets or kmeta if I'm using frozen fruit?
Could the peptic enzyme have inhibited the yeast growth for a week

 

[wildhair]

I didn't think the peptic enzyme would hurt the yeast, but it's always recommended to add it 12 hrs. after the kmeta, so.......... I wasn't sure. Thanks for clearing it up.

Good point on the cold not killing the yeast. I will continue using the k-meta at the start-up. Appreciated.

 

[wildhair]

Sorry, I mis-read what you typed, I thought you put in 3-1/8 tsps, not that you put in 3 each 1/8 tsp doses. Your thought that the dosage may have been on the high side due to only having to add 2 gallons of water has merit, that could elevate the levels enough to slow it down. Perhaps it was the combo of a little high on the sulfite, lowish temps and the first packet being on the old side that slowed down the startup, glad to hear it's chugging along now. To my knowledge, pectic enzyme doesn't have any effect on the yeast getting going.

I suspected that I may have not typed it quite right. I think the supfite may have been a bit high because even after a week of no fermentation - there was no "off" taste or order. Nothing unwanted had up residence.

This was also the first time I did NOT bag the rhubarb and wondered if that could have had an effect on retarding the yeast. Just looking for mistakes I do NOT want to repeat.

It's down to 1.030 this morning. And still a beautiful pink color.