Hi,
Most folks believe that those silvery bags and pouches are Mylar as that is what they are advertised as. Nothing could be further from the truth. 99.44% of bags and pouches advertised as Mylar are not mylar. MYLAR(R) is the patented and trademarked two stage process that stretches the PET in two directions and is then heat set to prevent shrinkage. Think lid on TV dinner, MRE. This process is applied to PET (polyethylene terephthalate) To creat BoPET(Biaxially-oriented polyethylene terephthalate) MYLAR(R) and costs double that of PET. I don't know any mfg of true MYLAR(R) food/coffee bags or pouches,
I have done considerable research on packaging for long term food storage, 10 yrs + and have found that Stockbagdepot has the best quality and pricing. I nitrogen flush and vacuum pack all my dry food products.The following links are for the bags I use. The 2-lb bag will hold approx 5-lb of rice, beans, peas, lentals, grains. These bags are 5.4 mil, 3 ply-PET.AL Foil, LLDPE, 0% Oxygen transmission, 0% Vapor transmission & 0% UV transmission.
http://www.stockbagdepot.com/gusseted-bags/quad-seal-foil/16-oz-silver_11010502.html, w/valve
http://www.stockbagdepot.com/gusseted-bags/quad-seal-foil/2-lb-silver.html w/valve
My system consists of the following. Lg cylinder of dry nitrogen, flow meter, electric operated solenoid valve, hose & tube to flush oxygen from bags &product. Hopper w/slide valve for product. 6x8" Denturist shaker table w/scale to shake and weigh bags when filling. Thinwall containers to hold bag shape when filling, sealing & vacuuming. Clamco Foot operated constant heat sealer. Dry vane rotary vacuum pump.
Last packaging project was about 1000-lbs of rice, beans, soup mixes, peas, lentils, seeds, sprouting seeds & grains over the course of several days.