In the past articles we have talked about canning in retort pouches for meals with meats, such as chicken, fish or red meat. We have expressed our own personal experiences and those of our commercial clients.
We have heard from several people and read on several blogs some new and very false information.
1) The suggestions of using less temperature due to the retorts being a thin package.
This is false. The need to pack the bags snugly in the canner creates a mass that must be heated though out to kill all bacteria. The bacteria only dies when proper temperature is reached for an extended period of time.
2) The suggestion of using less time due to the retorts being a thin package.
This is false. The mass created by packing the bags snugly to avoid blow outs requires more time to ensure the center of the canned product reaches the proper temperature. We suggest no less than 30% longer time than suggested home canning guidelines. Example a 60 minute can would require 90 minutes in retorts to be safe. Again there is no scientific data on this example.
3) We have read where non retorts such as mylar type bags are being used.
This is suggested as a less expensive option. Retorts are specifically designed with special air barrier properties, they are non toxic. Mylar does not have the air barrier properties nor is the toxicity rated for canning. Mylar is a polyester product not suitable for food and heat. Any reseller selling bags that are not the standard FDA Gold Retort bag, should display the retort bag manufacturer specs proving their bags are actually retort not just a food package. A reseller will gladly have this information posted for customers. Beware if you do not see this information clearly posted.
4) Many non vacuum packaging companies are suggesting not to vacuum seal.
All retorts on a commercial basis are vacuum sealed. Either by a standard chamber unit or a roll stock unit. To achieve 100% successful retort canning, the bags are vacuum sealed. Leaving the air in the bags as the product boils the side seams will give way and leak. Also with air left in the bag it is extremely hard to see if the product inside has gone bad.
We would like to express the extreme dangers of some of these suggestions. We use 30% more time than the home canning instructions to ensure the entire mass is completely heated though out. Using standard home canning heat instructions never less than 10lbs. We have used these instructions ourselves with great success. However there is no scientific information about retort canning and we are only expressing our own experiences. Until the scientific research has been completed you are canning retorts at your own risk.
We have been contacted by Dr. Elizabeth Andress with her concerns about retort canning and the non scientific information. Although hundreds of people have used retorts for their canning and it is widely used in the commercial industry. There is no laboratory scientific information to give exact time and temperatures especially for meats.
Dr. Andress wrote the book for USDA for home canning. We are excited to work with her in the near future. We look forward to her scientific research to publish her next canning book, using retort pouches.
We encourage all to be safe, use longer times, and no less than 10 lbs of pressure on non acid food such as any meat of fish product. If the bag is open do not eat and please discard it. If the bag expands like a balloon while in storage do not open or eat. Always reheat any home canned foods before eating to ensure bacterial has been destroyed.
We have enclosed Dr. Andress information as she is the USDA expert on home canning. Dr. Andress has not given any suggestions on proper canning of retorts and at this point does not condone the use of retorts in home canning. But rather is concerned about the misinformation or lack of information being posted. We hope to be able to post scientific guidelines very soon.