Regulatory Changes Affecting the Production and Use of Fats and Oils: Focus on Partially Hydrogenated Oils

Partially hydrogenated oils (PHO), the products of incomplete catalytic hydrogenation of food oils, have been widely employed by the food industry for more than a century. Their exceptional stability and technologic characteristics made them the preferred choice for the production of several food products including margarines, bakery goods, and frying oils. Some of these highly prized characteristics were provided by the high content in trans fatty acids (TFA), defined as fatty acids with one or more isolated double bond in trans configuration. The discovery of negative health effects associated with dietary intake of TFA triggered world-wide a wave of regulatory actions aimed to curb their consumption. PHO became the main target of most campaigns aimed to reduce consumption of TFA, and their fortune in the food industry progressively faded. At the 2017, AOCS Annual Meeting in Orlando, a group of experts from regulatory agencies and industry from North America and Europe met to discuss the current status of government regulations and industry adaptations regarding the productions and use of PHO. The discussion was enriched by including the impact on fats and oils production of the 2016 amendment of the Toxic Substances Control Act of 1976 (TSCA). The present publication may not include all regulatory changes that took place after this symposium, in 2017.     

Evidence of an Enzymatic Source of Off Flavors in “Lipoxygenase-Null” Soybeans

The utilization of soybean products as food ingredients and foods is often limited by their beany-grassy flavor. Eliminating seed lipoxygenase (LOX) isozymes 1, 2 and 3 reduces the amounts of volatile off-flavor compounds in stored soybeans and soy products significantly, but they are not completely eliminated. The present work presents evidence that lipoxygenase-null (LOX-null) soybeans contain a LOX-like enzyme that is responsible for the off-flavors in LOX-null soybeans. Volatiles production in triple LOX-null soybeans was terminated by heat treatment, which suggests an enzymatic cause to the off-flavors. The source is LOX-like in that the volatile compounds produced are similar to LOX-generated products of polyunsaturated fatty acids. Oxygen was consumed when a LOX-null protein solution was incubated with crude soybean oil suggesting that the enzyme catalyzed oxygen consuming reactions. The generation of flavor compounds was inhibited by the typical LOX inhibitors propyl gallate and nordihydroguaiaretic acid (NDGA). The enzyme appears to be more active with phosphatidylcholine than with other lipid substrates. The cause of the off-flavors in LOX-null beans appears to have enzyme-like characteristics. This is the first report of the initial characterization of this LOX-like enzyme.     

Molecular Mechanisms of Inhibition of Protein Amyloid Fibril Formation: Evidence and Perspectives Based on Kinetic Models

Inhibition of fibril formation is considered a possible treatment strategy for amyloid-related diseases. Understanding the molecular nature of inhibitor action is crucial for the design of drug candidates. In the present review, we describe the common kinetic models of fibril formation and classify known inhibitors by the mechanism of their interactions with the aggregating protein and its oligomers. This mechanism determines the step or steps of the aggregation process that become inhibited and the observed changes in kinetics and equilibrium of fibril formation. The results of numerous studies indicate that possible approaches to antiamyloid inhibitor discovery include the search for the strong binders of protein monomers, cappers blocking the ends of the growing fibril, or the species absorbing on the surface of oligomers preventing nucleation. Strongly binding inhibitors stabilizing the native state can be promising for the structured proteins while designing the drug candidates targeting disordered proteins is challenging.     

Commercialization of high oleic canola oils

High oleic canola oils were developed through plant breeding in the 1980's as a trans fat solution. More than 25 years after its initial launch, high oleic canola oils include a series of products with fatty acid profiles tailored for both foodservice and food processing. High oleic canola oil has taken most of the market for trait enhanced oils while other specialty oils have either seen significant market share reduction or failure. High oleic canola oils with 23%–27% linoleic acid are ideal for fried foods, while those with less than 20% are most suitable in the manufacture of shelf stable foods. In addition to improved nutrition, the next generation of high oleic canola oils will significantly reduce packaging costs.     

Oxidative Stability of Polyunsaturated Triacylglycerols Encapsulated in Oleaginous Yeast

Oleaginous yeast cells have the ability to synthesize oil from carbon sources or to adsorb fatty acids from their growth medium. Fish oil or conjugated linoleic acid (CLA)-rich oils encapsulated in Cryptococcus curvatus were protected from oxidation for more than 7 weeks. Oil-containing dead and viable yeast as well as oils extracted from dead or viable yeast were incubated at 52 °C in the dark. Oils extracted from yeast at the beginning of the experiment began oxidizing almost immediately and exceeded peroxide values (PV) of 20 mequiv/kg within a few days and eventually reaching PV > 100 mequiv/kg. After 56 days of incubation the PV value of oil from viable cells grown on fish oil was 3.8 ± 0.1 and 5.5 ± 0.8 mequiv/kg from dead cells. After 42 days of incubation the PV of oil from viable CLA containing yeast was 1.1 ± 0.2 mequiv/kg and 1.7 ± 0.5 from dead CLA containing yeast. C. curvatus encapsulation significantly improved oxidative stability of long-chain polyunsaturated fatty acids (LCPUFA) and CLA. Yeast cell viability was not critical for oxidative stability of the encapsulated oil.