Food, feed, and agricultural testing labs have standardized on ANKOM Technology's automated extraction systems for good reason: the XT10 and XT15 Fat/Oil Extractors and the 200, 2000, DELTA, and TDF Fiber Analyzers eliminate the manual drudgery of classical Soxhlet and detergent fiber methods while improving precision. But automation of the extraction step is only half the story. Every one of these official methods — crude fat, total fat, and certain dietary fiber determinations — ends the same way: a solvent must be evaporated before a gravimetric weight is taken, or a filtrate must be concentrated before instrumental analysis. That final step is where a properly matched nitrogen blowdown evaporator earns its place on the bench.
The Extraction Half of the Story: ANKOM XT10/XT15
The ANKOM XT15 automates AOCS Official Procedure Am 5-04, a high-temperature solvent extraction method that determines crude fat by exhaustively extracting a sample with petroleum ether under reflux, then drying and weighing the residue. The XT15 handles the bulk extraction elegantly: it batches up to 15 samples, recovers roughly 97% of the solvent automatically, and reduces most runs to well under an hour. Its lower-cost sibling, the XT10, follows the same AOCS Am 5-04 crude fat procedure with manual solvent recycling (~90% recovery) for labs running smaller daily volumes.
Both instruments still finish with a fundamentally manual step: the extracted lipid, once separated from bulk solvent, must be dried to constant weight before it is weighed. ANKOM's own application documentation describes this directly, noting that after extraction "the solvent and fat layer is poured off, and the solvent is evaporated" as part of the official crude fat procedure. This isn't unique to ANKOM's workflow — it reflects the underlying AOCS/AOAC chemistry. A 2017 review of food lipid analytical techniques from the University of Nebraska–Lincoln's Digital Commons confirms that related AOAC crude fat methods require the lipid extract to be dried to a stable weight after Soxhlet-type extraction before quantitation. A 2021 gravimetric fat method study on olive samples, published via PubMed Central, likewise states that "after the extraction, the solvent is evaporated and dried until it reaches a constant weight" before total fat is calculated.
This is precisely the operation a nitrogen blowdown evaporator is engineered for. Organomation's N-EVAP, MULTIVAP, and MICROVAP lines apply a gentle, adjustable stream of nitrogen gas — often paired with mild heat — to strip residual solvent from a sample without the thermal degradation, oxidation, or splash-loss risk of uncontrolled oven or hot-plate drying. Compared to letting fat/oil residues dry unsupervised after an XT10/XT15 run, a nitrogen evaporator gives the technician precise, repeatable control over the drying endpoint — which matters directly for the accuracy of a gravimetric fat determination, since retained solvent or over-dried, oxidized lipid both skew the final percentage. For labs pushing extracted lipids further downstream into fatty acid methyl ester (FAME) profiling by GC, the case strengthens further: a published FAME sample-prep protocol from the UC Davis Stable Isotope Facility instructs that low-abundance extracts "may be carefully dried under a gentle stream of nitrogen, re-dissolved in a reduced volume" of solvent prior to injection, and a marine-lipid FAME method used at Woods Hole Oceanographic Institution describes concentrating pooled extracts "to approximately 1 mL under a stream of nitrogen" before final solvent removal. An XT-series extraction paired with a nitrogen evaporator is effectively two halves of the same documented analytical method.
The Fiber Side: 200, 2000, DELTA, and TDF
ANKOM's fiber analyzers automate acid detergent, neutral detergent, and crude fiber determinations by controlling digestion, rinsing, and filtration inside a sealed vessel using Filter Bag Technology, batch-processing up to 24 samples at a time on the 200, 2000, and DELTA platforms. For straightforward ADF/NDF/crude fiber work, the endpoint is an oven-dried, gravimetrically weighed filter bag — no solvent evaporation step is required beyond the acetone rinse-and-air-dry sequence built into the standard method.
Where nitrogen evaporation becomes relevant on the fiber side is the TDF (Total Dietary Fiber) Analyzer. ANKOM specifically designed the TDF system so users can "perform stand-alone IDF, SDF, and TDF analyses, as well as capture filtrate for subsequent HPLC analysis." This matters because the current AOAC 2022.01 method for insoluble, soluble, and total dietary fiber — validated in a 2022 study led by Barry McCleary and published in PMC — quantifies the soluble dietary fiber fraction that stays in solution (SDFS) by recovering the ethanol filtrate and analyzing it by liquid chromatography rather than gravimetrically. A Shimadzu application note on dietary fiber analysis in functional beverages describes the same workflow: SDFS is measured "by recovering the filtrate from the enzymatic-gravimetric method, removing proteins and salts from ethanol-soluble components using ion-exchange resin, and then analyzing with HPLC." Before that filtrate can be cleanly injected, labs frequently need to concentrate it or exchange it into a compatible solvent — a controlled, low-temperature nitrogen blowdown step protects thermally labile fiber-derived analytes far better than rotary evaporation or uncontrolled heat drying.
One Bench, One Workflow
The throughline across both the fat/oil and dietary fiber applications is the same: ANKOM's extractors excel at the front end — automating digestion, extraction, and filtration to official AOCS and AOAC methods — while a nitrogen blowdown evaporator excels at the back end, delivering the controlled, gentle solvent removal that both classical gravimetric methods and modern chromatographic follow-up analyses require. For labs running XT10/XT15 fat extractions or TDF dietary fiber analyses, adding an Organomation N-EVAP, MULTIVAP, or MICROVAP isn't an incidental accessory purchase — it completes the documented analytical method, sample by sample, with the reproducibility that regulatory and nutritional-labeling testing demands.