Short Communication Branched chain fatty acids concentrate prepared from butter oil via urea adduction Samriddh Mudgal 1 , Rinat R. Ran-Ressler 2 , Lei Liu 1,2 , J. Thomas Brenna 1,2 and Syed S. H. Rizvi 1 1 Institute of Food Science, Cornell University, Ithaca, NY, USA 2 Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA Saturated branched chain fatty acids (BCFA) intake in the US is greater than that of other bioactive fatty acids (FA), yet little information is available on methodologies to concentrate them. We report here the effect of urea-to-FA (urea:FA) ratio, adduction time, and temperature on the enrichment of branched chain fatty acids (BCFA) from butter oil. Urea adducts precipitate both saturated and monounsaturated hydrocarbon chains as urea complexes, leaving solubilized polyunsaturated FA and BCFA in the non- urea adduct fraction (NUA). The optimum urea:FA ratio was found to be 4:1 and the optimum temperature to be 4°C. Adduction time had negligible effect on BCFA enrichment. Anteiso-15:0 was most enriched across major BCFA under all conditions of temperature, time, and urea:FA ratio studied. In our preferred embodiment, a two-stage urea adduction procedure applied to hydrolyzed butter oil resulted in an enrichment from <2% BCFA in the starting oil to >11% BCFA, indicating an enrichment factor of >6. The best method has a first stage performed at 4°C and urea:FA ratio of 4:1, and a second stage at 30°C and lower urea:FA ratio (2:1). Overall yield of BCFA in enriched fraction was about 10% of starting BCFA for two stages. Practical applications: BCFA are constituents of the GI tract of healthy newborns and are known to prevent necrotizing enterocolitis. The average per capita BCFA intake of Americans is estimated to be about 220 mg/day from dairy whereas based on the current dietary recommendations of USDA it should be about 400 mg/day from dairy alone with total amounting to 575 mg/day including beef. Using the results of the current study, enriched BCFA concentrates can be prepared to meet the demand. Keywords: Branched chain FA / Butter oil / Gas chromatography / Urea adduction Received: February 28, 2015 / Revised: April 15, 2015 / Accepted: April 23, 2015 DOI: 10.1002/ejlt.201500110 1 Introduction Branched chain fatty acids (BCFA) are primarily saturated FA having one or more methyl branch along the carbon chain. Generally the methyl branching is at the ultimate or penultimate carbon, with specific structures designated as “iso” or “anteiso,” respectively [1]. BCFAs are a distinct components of ruminant milk and adipose tissue, for instance, in cattle [2], sheep [3] and goats, as well as other animals with symbiotic fermentations such as beavers [4]. Eight or nine several specific BCFA, are found in milk and tissue of ruminants including sheep and goats, presumably synthesized by ruminal organisms that rely on them for membrane lipids [1]. Recently a study showed that BCFA constitutes 2% w/w of cow milk fat in the US retail milk supply [5]. Lanolin, wool wax, BCFA amounts exceed 40% [6], and many are alpha-hydroxylated [7]. In humans, BCFA are found mainly on the skin where they are synthesized by the sebaceous and meibomium glands, and are particularly rich in vernix caseosa, the white waxy material on the skin of human newborns. Nutritionally, they have long been known to be a component of colostrum and mature breast milk at up to 1.5% w/w [8]. They are also a prominent component of dairy and beef fat, constituting about 2% of all FA, and it has been estimated that Americans consume more than 400 mg of total BCFA daily, with around 220 mg/day and 180 mg/day sourced from dairy and beef, respectively [5]. One of the recently presented experimental studies indicates the effect of BCFA nutrition in a neonatal rat pup model [9]. BCFA reduced the incidence of necrotizing enterocolitis by more than 50%, altered the developing intestinal microbiota by supporting organisms Correspondence: Samriddh Mudgal, Stocking Hall, Institute of Food Science, Cornell University, Ithaca, NY 14853, USA E-mail: sm2295@cornell.edu Eur. J. Lipid Sci. Technol. 2015, 117, 0000–0000 1 ß 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim www.ejlst.com