What are some alternative phrases for "using the whole buffalo"?

Solution 1:

Zero waste seems to be a standard term.

https://en.m.wikipedia.org/wiki/Zero_waste

http://zwia.org says :

“Zero Waste: The conservation of all resources by means of responsible production, consumption, reuse, and recovery of products, packaging, and materials without burning and with no discharges to land, water, or air that threaten the environment or human health.”

Solution 2:

Using the whole Buffalo in cooking terms would be nose to tail.

From "What is nose to tail?" at Organic and Quality Foods:

Recently there’s been a movement towards nose to tail eating. That is, consuming many different parts of an animal, so it doesn’t go to waste. …

Here in Australia, the nose to tail movement is picking up momentum with farms such as River Cottage Australia in NSW embracing the philosophy of ‘nothing is wasted, and everything is celebrated’. It runs a nose to tail cooking course that teaches home cooks how to ‘love offal’ with a day of learning how to cook lesser-used cuts of meat. So next time you’re planning your shopping list, consider how you could use the cheaper, less popular cuts of meat from organic, sustainable producers. It may not be as quick to cook, but at least, you’ll know the animal was raised humanely, and its life didn’t go to waste.

From "Thrifty & Green: Why 'Nose to Tail' Is Back on the Menu" at Clean Eating:

Fancy an artisanal pâté, crispy pigs’ ears or sautéed sweetbreads? If so, you’re taking part in one of this season’s hottest trends: nose-to-tail eating. …

A top trend of 2018, nose-to-tail eating is a philosophy of using every part of the animal in food preparation, letting nothing go to waste. Aside from its appeal as a more traditional diet, it’s also one of the most economically and environmentally friendly ways to approach working with meat. Plus, it aims to squash our squeamishness: from charcuterie to cod cheeks, nose to tail celebrates traditionally prepared dishes that feature overlooked or lesser-known parts.

The term nose to tail was coined by Fergus Henderson in 2004 in his book The Whole Beast: Nose to Tail Eating.

Even if the term is not being applied to food, it would be understood in a figurative sense.

Solution 3:

As in: not one iota TFD an idiom

The plant wasted not one iota of raw materials in its production of X.

not a single, tiny bit; not at all.

An iota is something very small like a dot, a mote, something miniscule.