Oil-containing foods

TABLE 2. Flavor and Odor Terms, Definitions, and Reference Standards Used in the Evaluation of Fats, Oils, and Oil-Containing Foods. 

Products and Uses Wheat germ oil is a rich source of this fat-soluble compound. It is found in bacon, fats (rendered animal), pork fat (rendered), and poultry. Useful as an antioxidant (added to oil-containing food to prevent it from getting rancid), dietary supplement, nutrient, and preservative. 

Induced changes in food aroma are frequently assessed by consumers as objectionable, for example, as rancid, fishy, metallic or cardboardhke, or as an undefined old or stale flavor. On the other hand, the fact that some volatile compounds, at a level below their off-flavor threshold values, contribute to the pleasant aroma of many fruits and vegetables and to rounding-off the aroma of many fator oil-containing foods should not be neglected. 

The quenching effect of carotenoids (transition of 02 to 02) is very fast (k = 3 X 10 1 mole s ). They also prevent energy transfer from excited-state chlorophyll to 02- Therefore, carotenoids are particularly suitable for protecting fat (oil)-containing food from Type II photooxidation. 

Petro-Canada Oils. Petro-Canada manufactures three oils specially refined for use as heat-transfer fluids. Calflo EG is a semisynthetic, paraffinic heat-transfer fluid specifically developed for use in systems where incidental contact with food may result. Calflo AE is a saturated paraffinic oil containing inhibitors to minimise oxidation. Calflo HTE is a saturated paraffinic oil inhibited to minimise oxidation. 

Unesterified tocopherols are found in a variety of foods however, concentration and isomer distribution of tocopherols vary gready with source. Typically, meat, fish, and dairy contain <40 mg/100 g of total tocopherols. Almost all (>75%) of this is a-tocopherol for most sources in this group. The variation in the content of meat and dairy products can be related to the content of the food ingested by the animal. A strong seasonal variation can also be observed. Vegetable oils contain significant levels of y-, P-, and 5-tocopherol, along with a-tocopherol (Table 3). 

Polyoxyethylated castor oil containing 42 moles of ethylene oxide may be used under the Federal Food, E)mg, and Cosmetic Act as an emulsifier in nitrocellulose coatings for paper and paperboard intended for use in contact with fatty foods at a maximum level of 8 wt % of the coating soHd (130). 

Maizura M, Fazilah A, Norziah MH and Karim AA. 2007. Antibacterial activity and mechanical properties of partially hydrolyzed sago starch-alginate edible film containing lemongrass oil. J Food Sci 72(6) 324—330. 

The selection of the most suitable antioxidant depends on the character of food and the targets which should be attained. Naturally occuring fats and oils contain indigenous antioxidants that protect the unsaturated lipids from free-radical destruction in their native vegetable and animal sources. On the other hand, fats and oils exist in a commingled fashion with reactive substances which cause their rapid decomposition. Intensity of oxidative alterations is also influenced by the shelf-life of products and storage conditions. All these facts should be considered when deciding whether any and if so what antioxidant will be used. 

As discussed above, cresols are widely distributed natural compounds. They are formed as metabolites of microbial activity and are excreted in the urine of mammals. Various plant lipid constituents, including many oils, contain cresols. Cresols have also been detected in certain foods and beverages such as tomatoes, tomato ketchup, cooked asparagus, various cheeses, butter, oil, red wine, distilled spirits, raw and roasted coffee, black tea, smoked foods, tobacco, and tobacco smoke (Fiege and Bayer 1987). However, very few monitoring data for cresols in food were found in the literature. 

K. Warner and N. A. M. EsMn, Methods to Assess Quality and Stability of Oils and Fat-Containing Foods, AOCS Press, Champaign, USA, 1995. 

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