Bacon Fat Research Articles

Current Trends in Levels of Volatile N-Nitrosamines in Fried Bacon and Fried-Out Bacon Fat

Commercially processed bacon samples purchased from the Washington, DC, retail market have been periodically analyzed since 1971 for the presence of volatile N-nitrosamines in the fried product. During that time, a downward trend in the concentration of N-nitrosopyrrolidine has been observed, and between 1978 and 1980 it plateaued at 4-30 ppb, with an average of 11 ppb. A recent survey, however, indicates a change in this downward trend, with N-nitrosopyrrolidine found at levels ranging from 1 to 65 ppb, average 21 ppb. Volatile N-nitrosamines were found at levels up to 110 ppb in the fried product and up to 85 ppb in the fried-out bacon fat.

N-Nitrosamine formation in fried-out bacon fat: evidence for nitrosation by lipid-bound nitrite

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTN-Nitrosamine formation in fried-out bacon fat: evidence for nitrosation by lipid-bound nitriteJoseph H. Hotchkiss, Alex J. Vecchio, and Holly D. RossCite this: J. Agric. Food Chem. 1985, 33, 1, 5–8Publication Date (Print):January 1, 1985Publication History Published online1 May 2002Published inissue 1 January 1985https://doi.org/10.1021/jf00061a002RIGHTS & PERMISSIONSArticle Views100Altmetric-Citations13LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (524 KB) Get e-Alerts Get e-Alerts

Sources of N-nitrosamine contamination in foods.

It has been well established that human foods may contain trace amounts of carcinogenic N-nitrosamines. Originally, it was thought that the use of nitrite as a curing agent for flesh foods was the major source of these trace compounds in the diet. Subsequent research has clearly shown that other processing and packaging procedures can also introduce trace amounts of these carcinogens into foods. These procedures include drying foods in direct flame heated air, migration from food contact surfaces and direct addition as contaminants. In addition, other reports of N-nitrosamines in foods have less well defined routes of contamination. These sources of N-nitrosamines in foods will each be briefly reviewed in this paper and recent data from our laboratory concerning N-nitrosamines in products which directly contact foods presented. We also are reporting the N-nitrosothiazolidine content of fried-out bacon fat.

A rapid liquid-liquid extraction cleanup method for determination of volatile N-nitrosamines in cooked-out bacon fat

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTA rapid liquid-liquid extraction cleanup method for determination of volatile N-nitrosamines in cooked-out bacon fatNrisinha P. Sen and Stephen S. SeamanCite this: J. Agric. Food Chem. 1982, 30, 2, 364–367Publication Date (Print):March 1, 1982Publication History Published online1 May 2002Published inissue 1 March 1982https://doi.org/10.1021/jf00110a039RIGHTS & PERMISSIONSArticle Views85Altmetric-Citations1LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (496 KB) Get e-Alerts Get e-Alerts

EFFECTS OF MICROWAVE COOKING ON FOOD FATTY ACIDS: NO EVIDENCE OF CHEMICAL ALTERATION OR ISOMERIZATION

ABSTRACTBecause of the current interest in the potential physiological effects of trans fatty acids and a brief report that microwave cooking causes isomerization of unsaturated fatty acids, we examined the effects of microwave treatments on the fatty acid composition of several food lipids, i.e., chicken fat, beef tallow, bacon fat, rainbow trout, peanut oil, and potato lipids. The data indicate that microwave cooking per se does not change the fatty acid pattern of these lipids nor cause isomerization of the unsaturated fatty acids.

The analysis of tocopherols in corn oil and bacon fat by thin‐layer chromatography and spot density measurement

SummaryThe two major tocopherols (α and γ forms) present in corn oil were separated, after removal of interfering lipids, by thin‐layer chromatography (TLC), and detected on the TLC plate by spraying with Gibbs' reagent (2,6‐dichloro‐p‐benzoquinone‐4‐chlorimine). Quantitation was achieved by densitometric scanning of the coloured spots, using a calibration curve prepared from reference samples of the pure α‐ and γ‐tocopherols. α‐tocopherol, added to bacon fat, was quantitatively recovered without measurable loss during the analysis. Other antioxidants commonly added to foodstuffs, with the exception of BHA and BHT, were not extracted. The method described has a detection limit of 20 ppm of α‐ or γ‐tocopherol for a given fat sample, hence permits the quantitation of either tocopherol in vitamin E‐rich materials, such as vegetable oils, but lacks the sensitivity to detect the trace amounts of tocopherols normally present in animal fatty tissues.

The effect of ascorbate reductants on N‐nitrosamine formation in a model system resembling bacon fat

AbstractThe nitrosation of dipropylamine and pyrrolidine have been examined in two‐phase systems comprising aqueous buffer and non‐polar solvent. Contrary to previous observations in purely aqueous systems, sodium ascorbate increased amine nitrosation in this two‐phase simulated fat system by between 5 and 25 times compared with ascorbate‐free controls. Lipophilic ascorbyl palmitate, however, generally reduced nitrosation.

Isolation of Volatile N-Nitrosamines in Edible Vegetable Oils and Cooked Bacon Fat

Abstract Volatile N-nitrosamines can be isolated from cooked bacon fat by the following procedures: The sample is distilled from alkaline solution and the nitrosamines are extracted with methylene chloride and cleaned up on a silica gel column (procedure A). The same procedures, preceded by an extraction with methylene chloride- sodium hydroxide, are used for isolation of N-nitrosamines from soybean oil samples (procedure B). Gas-liquid chromatography with the thermionic detector was used for the determinative step. Recoveries of 14 N-nitrosamines added to 25 g soybean oil samples at 10 and 20 ppb ranged from 67 to 100% for procedure B; these recoveries were 5舓10% higher than those from procedure A. No nitrosamines were detected in 4 commercial samples of soybean oil; however, they were found in cooked bacon fat at levels ranging from 45 to 207 ppb (μg/kg).

Dielectric Properties of Commercial Cooking Oils

SUMMARY— The finished drying of potato chips represents the first large‐scale use of microwaves in the food industry on a continuous basis. Hence it was deemed desirable to study the dielectric properties of various types of commercial cooking oils.The dielectric constant (ɛ), and loss tangent (tans) of 11 commercial fats and oils have been determined at three different temperatures and at three different frequencies in the microwave range. The differences in dielectric properties among these fats and oils appear to be attributable to the phase (solid vs. liquid) of the material and generally correspond to the degree of unsaturation as evidenced by iodine values. The differences in loss factors among these fats and oils at any given temperature and frequency (within the range at which the measurements were made) are too small to be of any practical importance in selecting any one of them for use in heating processes using microwaves or in choosing an optimal frequency (300, 1000 or 3000 megahertz, MHz).Data for one of the oils (number 9) were obtained over a wider range of frequencies and indicate that the loss factor peak(s) is/are found in the frequency range of 100 to 1000 MHz. Furthermore, from the data obtained for the other oils, it should be safe to assume that this oil is representative of dielectric properties of the entire group. The dielectric properties of bacon fat rendered by microwaves are almost identical to those of bacon fat rendered by conventional means.

Fatty Acid Composition of Tissues of Pigs Fed Whole Peanuts

SUMMARYThe liver of pigs fed a whole‐peanut‐supplemented diet significantly increased in fatty acid means in 18:1 (carbon chain length: number of double bonds) and 18:2, and significantly decreased in 18:0, compared with the liver of pigs on a control diet. The kidney decreased significantly in 14:0 and 17:0, and the heart decreased significantly in 16:1. These changes were primarily the result of an increased total lipid consumption since the fatty acid compositions of both dietary lipids were very similar. Of all the tissues studied (liver, heart, kidney, ham, shoulder, skin, bacon fat, and chop) the liver contained the largest amount of 18:0, 18:2, and 20:4, and the least amount of 14:0, 16:0, 16:1, 17:1, and 18:1.

Visual judgements of quality in meat II. A simplification of the assessment of the proportion of lean to fat in bacon

1. The visual judgement of bacon quality called the ‘proportion of lean to fat’ has been simplified by breaking down the overall assessment of the surface seen on the cut bacon side at the last rib into four simpler scores—of the ‘eye’-muscle size and shape, the amount and distribution of fat on the back rasher, the streak thickness and the proportion of lean to fat in the streak, each judged on a 10-point scale. An experiment is described in which eight experienced judges attempted to score these new characteristics in conjunction with the overall assessment.2. The judging standard adopted in the overall assessment of the proportion of lean to fat varied less from batch to batch in this experiment (in which the seven batches were arrayed in fixed positions and assessed in one day) than in an earlier experiment (when the examples seen in each batch could be shuffled and the eleven batches were seen several days apart). The ranking of judges according to their discrimination and repeatability for the overall assessment was also changed in the second experiment.

Visual judgements of quality in meat I. Assessments of the proportion of lean to fat in bacon from photographs of the cut side

1. Eight experienced judges used a 20-point scoring scale in different ways when assessing the ‘proportion of lean to fat’ from the same photographs of cut bacon sides presented in the same arrangements. The average score for the 220 judgements made during the experiment by a single judge, which represents his over-all level of scoring or ‘standard of judging’, ranged from 13·7 to 12·0. The standard deviation, a measure of the degree of discrimination attempted by the judge, ranged from 3·26 to 4·74.2. The judges varied in their consistency of assessment or ‘repeatability’. The standard error for a single judge, measuring the extent of the variation of his scores within photographs, ranged from 0·89 to 1·99. The judges who attempted to discriminate most between photographs tended to be the least consistent in their judgements, although one judge was a notable exception to this trend.3. The consistency of judgement tended to decrease from the good (high-scoring) rashers to the poor (low-scoring) rashers, but this effect was more marked for some judges than for others.4. Some of the variation in the scores awarded to each photograph was due to alterations in the standard of judging from batch to batch. When this was allowed for, the standard errors were all reduced and ranged from 0·61 to 1·31. The judges tended to adjust their standards according to the average quality of the batch being assessed. This led to the variation among the average scores for the batches being less than it would have been had their standards remained constant.5. Alterations in the standard of judging during the experiment affected the scores awarded to good (high-scoring) rashers rather less than those awarded to poor (low-scoring) ones.6. The correlations between the individual judge's mean scores for the forty-four photographs and the over-all mean scores were very high. For seven judges, they ranged from 0·962 to 0·984, whereas for the eighth judge the correlation was 0·918. The lower correlation for this judge was due to two rashers with very thin fat being heavily marked down.7. The correlations between the over-all mean scores and two different combinations of three objective measurements were both about 0·92; these measurements were therefore slightly less closely related to the over-all scores than were an individual judge's mean scores.8. The possibility of making the experimental technique more realistic and of improving the precision of such visual judgements by providing photographic scales of reference are discussed.

CANADIAN WILTSHIRE BACON: XVII. RANCIDITY IN PORK FAT AFTER FROZEN STORAGE AND CONVERSION TO BACON

Determination of the peroxide oxygen and free fatty acid content of the fat of pork, stored under various conditions and subsequently converted to bacon, showed that temperature, method of wrapping, and stage in the conversion to bacon were the most important factors governing the oxidation and hydrolysis of the fat. Of the conditions studied, storage at temperatures of −18° to −23 °C. with an aluminium foil wrapping, followed by thawing in brine or pickle were the most effective in retarding rancidity. The greatest increase in the peroxide oxygen content of the fat occurred during cure, whereas that of free fatty acid increased at a relatively uniform rate throughout the various conversion steps. Smoking had greater antioxidant effect on the fat than pale-drying. Since in all instances the content of free fatty acid was low, spoilage in pork or bacon fat is primarily due to oxidation.

Nutrition of the bacon pig: IV. The influence on growth, conformation and carcass quality of including meat meals of widely-differing fat content in the rations of bacon pigs

The amount of oil in the diet and its degree of unsaturation are known to exert an important effect on the nature of the fat deposited in the body of the growing pig, foods of high oil content tending to give rise to bacon carcasses containing fat of an undesirably soft and unsaturated character. For this reason, authorities on pig nutrition are agreed on the desirability of excluding from the dietary of the bacon pig all foods containing more than a small percentage of oil. It has been stated that, in order to avoid the danger of producing carcasses with soft fat, the meal ration of the fattening pig should be made up so as to contain no more than about 3% of oil.This prejudice against the use of feeding stuffs rich in oil has been transferred, somewhat unquestioningly perhaps, to feeding stuffs rich in fat. Feeding meat meal, for example, contains normally from 8 to 10 % of fat, and manufacturers complain of the difficulty of securing sales of this product for pig-feeding on account of the view generally held that its high fat content would occasion the production of soft fat in the resultant bacon or a carcass with an excessive amount of fat. To meet this prejudice, therefore, the meat meal as ordinarily produced is frequently submitted to a process of de-greasing with petroleum benzine at about 200° F. so as to give a meat meal containing about 3% of fat. This procedure, however, not only adds to the cost of the manufacture of meat meal, but may actually lead to a distinct lowering of the digestibility of the product (Woodman & Evans, 1937).

Infra-red Transmission of the Flesh

The spectral energy of a light transmitted through the cheek was tested photographically in the region of λ0.86μ, and also by a spectrometer throughout the whole spectrum. A very sensitive vacuum thermocouple was used. The photographs of the spectrum showed 14% transmission of λ0.86μ through the cheek. The cheek transmitted a maximum of 20% at λ1.15μ and the water in the body cut off the longer wave lengths. The spectral energy transmitted by bacon fat was found to be similar to that of the cheek; however, it transmitted nearly five times as much energy. The ordinary incandescent electric light with filters to cut out the visible and infrared beyond λ1.4μ is ideal for deep penetration of light into the body.

The influence of palm kernel meal on the composition of bacon fat

The first page of this article is displayed as the abstract.