The only nut I have a problem with are pecans. After roasting them they seem to have a shelf life of about 3 months +/-. I use them in a bark and you can see the fat bloom slowly take over after its time period has elapsed and holding temps don't seem to matter much.

I started doing some digging and came across conflicting advice. One camp said to candy them and that would stop it, the other camp said candying them would not stop it but would increase the rancidity.

Is anyone here doing 6mo-1year stability of pecans or other nuts in their chocolate and know how to reduce if not eliminate the fat rancidity of the nut?

updated by @andy-ciordia: 04/10/15 22:20:41

There's nothing you can do to stop oxidative rancidity in nutmeats, other than defatting them. Period.

There are lots of things you can do to slow it down. Generally speaking, if you put a barrier around the nuts that can block oxygen, that helps (ie candying provides a sugar barrier). The lower temperatures you can expose the nuts to, the better (ie roast lower for longer vs very hot for shorter).

A couple of things to note:

Chocolate is a terrible oxygen barrier.

Sugar barriers, if intact, are great. However it's quite challenging to keep sugar from getting cracks in it, which lets the oxygen through.

You will never. Ever. get 1 year stability in pecans, unless you keep them frozen. Or perhaps stored in space where there is no oxygen.

Thanks Sebastian that puts a perfect perspective on it and a slight buzz kill to boot. I guess if we ever got into vacuum sealing or something close it might help but even then w/o an inert gas insertion I think it'd be limited usefulness.

Oh well. I guess I'll just keep that product at a low inventory item and also start storing my pecan inventory in the freezer or ordering less.

Many thoughts and many thanks for the lesson.

Sorry to rain on the parade. Unfortunately highly unsaturated fats at high levels + air and high temps (think ruptured cells) don't end well over long periods of time. There are lots of handling procedures that can be done during roasting that can minimize the impact, but not eliminate it.

Andy - I looked into this myself (for different reasons) last fall. The good news is that you can get vacuum sealing systems with a nitrogen flush for less than you might think. I saw some for as little as $3,000. The bad news is that these systems tend to be more geared toward things that can be easily poured into the bags. Many confections would have to be hand work, which would eliminate most of the automatic functions that are potentially available.

That having been said, it all depends on your volume. If your volume is not that large then filling the bags by hand may be no problem anyway. And if your volume is large you can get an automated solution designed for nearly anything. As usual, it's when you're somewhere in the middle that there is no easy solution.

As for your specific issue with pecans I'm no expert on nuts but my research has always indicated that the only (and probably best) way to extend the life of pecans is through temperature. In particular freezing them. Pecans apparently hold up to freezing (and even thawing and re-freezing) much better than most nuts. Of course how your confections might hold up to this is another story. But if you place your product in an vacuum-sealed bag with a nitrogen flush and then keep them in the freezer you might actually get that one year. Of course you'll have to set aside a year to test it out! And even if it works I would be surprised if there wasn't some degradation in the quality of the nuts. But maybe

True enough! I only threw out a year as a distant thought. If I can get 6 months out of a product without tampering or additional science I'm an ecstatic camper. A lot of my other barks and toffees seem to easily coast into that frame as long as heat/humidity don't beat them up.

That's good news on a nitrogen flush sealer too. I'll have to keep that in mind. We're pondering what our next growths steps would be and if we go for an industrial space for production that + a walk-in would be a good combo. Industrial space or chocolate bourbon bar.. oh the decisions.

We're already pondering some finished/packed freezer tests but our freezer space is rather limited at this time with other items.

Just trying to get more longevity out of products so I can do a larger up front run and then work on the myriad of other projects and production needs.

Thanks for your input too!