Lard is for the most part fairly shelf stable, but as mentioned, it’ unsaturated, which is why it’s good. The problem with it though, as with all unsaturated fats/oils, from a chemical standpoint, is that the unsaturated portion, actually wants to be saturated. So if there is an atom floating around loose (loosely refered to as an oxidants, or free-radicals) it will bind to it, and thus becomes rancid. Increased amounts of heat, light and air all either have and/or create free-radicals, and thus cause it to go rancid faster. Dark, cold, and as free of air as possible will all help to keep the lard/tallow/other rendered fats from going rancid for longer.

Freezing isn’t going to do too much for it though, because the ‘freezing point’ being referred to is that of water, not of say a fat. At the point of freezing water, (0 degrees C) fat is actually not frozen. It will slow the process down, but no more than having it in the refridgerator will, which is why a comment above mentioned it having gone bad in the freezer.

That being said, storing it like all other canned/bottled foods, in a cool dark room it will still store for wuite some time, quite possibly for several months. Just pay attention to it, and when it starts to smell off, toss it and get some new..

The problem is from the actual sugar, which called Lactose, a double sugar (disaccharide) composed of glucose and galactose. While milk itself generally has most of the sugar, all dairy products will have some amount, even after clarification of the butter, and regardless of whether the butter is home-made.

If there is adifferent problem, such as allergic reaction, there isn’t a viable cure, except for very low doseages, in the hopes that the immune system stops treating the proteins and other nutrients as foreign bodies.

The benefit sought after with the pork lard, is that pork has neither the same proteins/nutrient combinations, nor does it have the lactose which needs to be broken down.

Speeking as a hard-core dairy lover, recently diagnosed with lactose-intolerance, a viable option however, would possibly (depending on the individual person) would be trying yogurt in place of creams/milk/cheeses, because the bacteria used for culturing the yogurt feed off the lactose, and break it down into it’s individual saccharides, (galactose and lactose) which do not need to be broken down by the digestive tract. The glucose is already prepared for use by the cells and brain, while the galactose is easily (well, non-chemically speakng it’s easy..) converted into glucose by the liver.

If you have the option to watch a Food Network show called Good Eats, the episode 4 from season 6 is actually all about culturing your own yogurt, and using that yogurt to make dressings, cream sauce and cheeses from it. (Actually watched it yesterday coincidentally..) And I culture my own yogurt every couple weeks in 2 gallon batches. It really is quite simple, tastes better than store-bought yogurt, and is about 1/4 the cost too!