Researchers Recover About 95 Percent of Fat From Ice Cream Waste With Simple Separation

A waste stream familiar to ice cream manufacturers could become a recoverable source of fat, with Penn State researchers reporting that simple centrifugation recovered about 95 percent of the fat in tested ice cream waste.

Nearly 5 percent of raw materials used in ice cream production can end up as waste, according to figures cited by the research team. Discarded batches, quality problems and equipment cleaning all contribute, while allergen controls can increase the volume that manufacturers cannot return directly to production.

The researchers tested waste supplied by Perry's Ice Cream using enzyme treatment, changes in acidity or alkalinity and centrifugation. The unexpectedly simple result was that the untreated control, processed by centrifugation, recovered about 95 percent of the fat while improving fat purity compared with the original waste.

Longer enzyme treatments did not increase total fat recovery and could reduce purity. Strong alkaline treatment also helped separation, but the study suggests manufacturers may not need a complicated process to capture much of the available fat.

A techno economic model estimated a minimum selling price of roughly 40 cents per kilogram for recovered fat. Economics improved as incoming waste contained more fat and as processing scale increased.

Potential outlets include replacing choice white grease used in animal feed or converting recovered fat into compounds for pharmaceutical, cosmetic and other applications. Those uses would require their own technical, regulatory and quality assessments before commercialization.

The work turns a routine processing loss into a broader circular manufacturing question. Instead of treating all off specification ice cream as a disposal cost, processors may be able to separate valuable components and reduce the economic burden of waste.