The new foodie trend of “snout to tail” cooking utilizes all
parts of the pig for sustainability and waste reduction as well as gastronomic
pleasure. But pigs themselves are masters of resource optimization: they can be
fed a dizzying variety of feedstuffs, much of which might otherwise become
refuse.
It’s this capability that Human Nutrition, Food and Animal
Sciences researcher Rajesh Jha is exploring in his research into alternative
feeds for swine, developing more cost-effective and sustainable animal
production systems. He has successfully evaluated a wide range, including a
number of locally produced options. Sweet potato, cassava, and taro show
promise, as do okara and macadamia nut cake. All have reasonably high, though
different, nutritive values and digestibility, so combinations can be used to
formulate diets for various animals.
The last two also have the advantage of being otherwise
waste products. Okara, the soybean pulp remaining after production of soymilk
or tofu, is often relegated to the landfill. However, Dr. Jha’s lab found it
very promising as pig feed due to its high nutritional value and digestibility.
Macadamia nut cake, a by-product from macadamia oil processing plants, used to
be thrown away as well. However, Dr. Jha shows that it also has high potential
as animal feed thanks to its high protein, energy values, and digestibility.
Now he is starting a chicken-feeding trial with macadamia nut cake as well.
Dr. Jha not only searches out new potential foods for swine;
he works to improve those already in use. A waste product commonly used as
swine feed is Distillers Dried Grains with Solubles (DDGS), a corn-derivative
by-product of ethanol production. DDGS is fed not only to pigs but to dairy and
beef cattle, poultry, and sheep. However, the digestibility of DDGS is quite
low; therefore, it can only comprise a relatively small proportion of their
diets. A highly competitive grant recently awarded by the National Pork Board
is allowing Dr. Jha to research ways to treat DDGS with enzymes to unlock its
nutrients and allow it to be used more effectively by the pigs who eat it,
leading to a reduction in the cost of their feed and increasing environmental
sustainability. Not only this, but he explains that this technique can work to
enhance the available nutrition of other feeds, including the local feedstuffs
he’s testing.
The best part? All this research is bolstering Hawai‘i’s
pig-farming industry, leading to more luscious local pork to eat, snout to tail.