Brown and Black Grease Suitability for Incorporation into Feeds and Suitability for Biofuels

2012 ◽  
Vol 75 (4) ◽  
pp. 731-737 ◽  
Author(s):  
PAULA MARIE L. WARD

Waste grease lipids used in animal feeds have been the cause of food recalls in Europe, where such materials were incorporated into animal feedstuffs. This resulted in unwanted residues in human food. The composition of such lipid sources has been lacking. Seventeen composite trap grease and isolated brown grease samples were analyzed. Analytes included nutrients, metals, and volatile organic compounds. Analytes were selected for relevance to wastewater treatment and resource reuse potential. Moisture averaged 89.4% and the pH was 3.8. The 5-day biological oxygen demand was 32,531 mg/liter, solids were 7.5%, and fats, oil, and grease were 48,970 mg/liter. Non–polychlorinated biphenyl volatile organic compounds were surveyed. In the 17 grease samples, 14 contained an average of 102.5 μg/liter chloroform; 11 samples contained acetone, averaging 369 μg/liter; 9 samples contained 2-butanone, with an average of 484 μg/liter; and 8 contained an average of 710 μg/liter methylene chloride and toluene at 311 μg/liter. The mean concentration of copper in 17 composite samples ranged from 15 to 239 mg/liter, iron averaged 314 mg/liter, lead means ranged from 2.5 to 24 mg/liter, and magnesium averaged 975 mg/liter. It is hypothesized that food preparation facility cleaning and chlorinated cleaning–disinfection agents combined with the organics in the low-pH environment of the traps produce potentially carcinogenic compounds. It is recommended that these waste grease materials be used as a feedstock for biofuel.

2020 ◽  
Vol 57 (6) ◽  
pp. 882-902 ◽  
Author(s):  
R.S. McWatters ◽  
D.D. Jones ◽  
R.K. Rowe ◽  
J.M. Markle

The excavation and analysis of the barrier systems for four engineered containment cells, constructed from 1984 to 1987, is described. Very limited polychlorinated biphenyl (PCB) migration was observed over the 22–25 year period prior to decommissioning. PCBs were predominantly, and preferentially, retarded by the geotextiles (GTXs) and, where present, geomembranes (GMBs). The migration of PCBs in the primary compacted clay liner (CCL) during this period was limited both when used alone and with a GMB. The exhumed GMBs, from both cover and base barriers, had diffusive properties (with respect to volatile organic compounds) comparable to unaged GMBs. For cells with a CCL as the primary base barrier, the inferred PCB diffusion coefficient, De, was 1–2 × 10−10 m2/s and distribution coefficient, Kd, was 10–15 mL/g. For cells where a GMB was the primary base barrier, the inferred PCB partitioning coefficient, Sgf, was 150 000 and diffusion coefficient, Dg, was 1 × 10−14 m2/s. Modelling beyond the 25 years in service predicts no unacceptable PCB impact of the landfill on groundwater and indicates that the design of the barrier system was adequate for an indefinite period given the low service temperatures to which it was subjected. In this diffusion-governed system, small changes to the diffusive properties were found to have a large impact on migration.


1969 ◽  
Vol 96 (3-4) ◽  
pp. 183-198
Author(s):  
José A. Dumas ◽  
Carlos E. Ortiz ◽  
Sheila Soler

For fresh market sweet potato [Ipomea batatas (L.) Lam] quality is defined in terms of attractiveness, sweetness, texture, and flavor composed of taste and odor after cooking. There is a scarcity of information regarding taste and volátiles of tropical type sweet potatoes. The first objective of this research was to provide a robust set of data for carbohydrate type and levels, alcohol insoluble solids (AIS) and volatile organic compounds (VOC) from six cultivars of sweet potato, data which will allow us to have a quantitative selection tool besides crop yield, tuber size and appearance. The second objective was to relate VOC differences among sweet potato cultivars that can be attributed to chemical and physical differences of the pulp before and after cooking. A three- harvest study was conducted to identify and determine major carbohydrate content, AIS, starch granule diameter and form, and tastes and odors of six cultivars of sweet potato, which were very sweet ('Gem'), sweet ('Miguela' and Travis'), moderately sweet ('Viola' and 'Martina') and non-sweet ('Ninety- nine'). The average AIS contents were 81, 77, 79, 85, 66, and 76% for 'Martina', 'Miguela', 'Ninety-nine', 'Viola', 'Gem' and 'Travis', respectively. Scanning electron micrograph (SEM) indicated that the average starch granule diameters were 12.9, 15.3, 16.9 and 25.2 |jm for 'Martina', 'Miguela', 'Ninety-nine' and 'Viola', respectively. In addition, all of the sweet potato starch granules had both spherical and polygonal granules. The cultivars with greatest change in AIS and maltose content (raw vs. baked) were 'Gem', the sweetest, and 'Travis'. Correlation between sucrose index (SI) and AIS for baked samples was 0.956; for AIS and sweetness, correlation was -0.823. A similar correlation between the AIS and maltose was obtained for the data from the three harvests (-0.8493). Fifty volatile organic compounds of baked sweet potatoes were trapped in cold methylene chloride. The predominant volátiles were hexanal, 3-pente-2-ol, and isoledene. Other sweet aromas detected were 2,4-decadienal, 2-pentyl furan, benzaldehyde, 4-methyl-4-hydroxy-2-pentanone, and benzene acetaldehyde. The great differences in relative concentrations of volátiles among cultivars seem to be related to the synthesis of maltose and the content of AIS.


2021 ◽  
Vol 96 (3-4) ◽  
pp. 183-198
Author(s):  
José A. Dumas ◽  
Carlos E. Ortiz ◽  
Sheila Soler

For fresh market sweet potato [Ipomea batatas (L.) Lam] quality is defined in terms of attractiveness, sweetness, texture, and flavor composed of taste and odor after cooking. There is a scarcity of information regarding taste and volatiles of tropical type sweet potatoes. The first objective of this research was to provide a robust set of data for carbohydrate type and levels, alcohol insoluble solids (AIS) and volatile organic compounds (VOC) from six cultivars of sweet potato, data which will allow us to have a quantitative selection tool besides crop yield, tuber size and appearance. The second objective was to relate VOC differences among sweet potato cultivars that can be attributed to chemical and physical differences of the pulp before and after cooking. A three harvest study was conducted to identify and determine major carbohydrate content, AIS, starch granule diameter and form, and tastes and odors of six cultivars of sweet potato, which were very sweet ('Gem'), sweet ('Miguela' and Travis'), moderately sweet ('Viola' and 'Martina') and non-sweet ('Ninetynine'). The average AIS contents were 81, 77, 79, 85, 66, and 76% for 'Martina', 'Miguela', 'Ninety-nine', 'Viola', 'Gem' and 'Travis', respectively. Scanning electron micrograph (SEM) indicated that the average starch granule diameters were 12.9, 15.3, 16.9 and 25.2 |jm for 'Martina', 'Miguela', 'Ninety-nine' and 'Viola', respectively. In addition, all of the sweet potato starch granules had both spherical and polygonal granules. The cultivars with greatest change in AIS and maltose content (raw vs. baked) were 'Gem', the sweetest, and 'Travis'.  Correlation between sucrose index (SI) and AIS for baked samples was 0.956; for AIS and sweetness, correlation was -0.823. A similar correlation between the AIS and maltose was obtained for the data from the three harvests (-0.8493).  Fifty volatile organic compounds of baked sweet potatoes were trapped in cold methylene chloride. The predominant volátiles were hexanal, 3-pente-2-ol, and isoledene. Other sweet aromas detected were 2,4-decadienal, 2-pentyl furan, benzaldehyde, 4-methyl-4-hydroxy-2-pentanone, and benzene acetaldehyde. The great differences in relative concentrations of volátiles among cultivars seem to be related to the synthesis of maltose and the content of AIS.  


Author(s):  
José A. Dumas ◽  
Carlos E. Ortiz ◽  
Sheila Soler

For fresh market sweet potato [Ipomea batatas (L.) Lam] quality is defined in terms of attractiveness, sweetness, texture, and flavor composed of taste and odor after cooking. There is a scarcity of information regarding taste and volátiles of tropical type sweet potatoes. The first objective of this research was to provide a robust set of data for carbohydrate type and levels, alcohol insoluble solids (AIS) and volatile organic compounds (VOC) from six cultivars of sweet potato, data which will allow us to have a quantitative selection tool besides crop yield, tuber size and appearance. The second objective was to relate VOC differences among sweet potato cultivars that can be attributed to chemical and physical differences of the pulp before and after cooking. A three- harvest study was conducted to identify and determine major carbohydrate content, AIS, starch granule diameter and form, and tastes and odors of six cultivars of sweet potato, which were very sweet ('Gem'), sweet ('Miguela' and Travis'), moderately sweet ('Viola' and 'Martina') and non-sweet ('Ninety- nine'). The average AIS contents were 81, 77, 79, 85, 66, and 76% for 'Martina', 'Miguela', 'Ninety-nine', 'Viola', 'Gem' and 'Travis', respectively. Scanning electron micrograph (SEM) indicated that the average starch granule diameters were 12.9, 15.3, 16.9 and 25.2 |jm for 'Martina', 'Miguela', 'Ninety-nine' and 'Viola', respectively. In addition, all of the sweet potato starch granules had both spherical and polygonal granules. The cultivars with greatest change in AIS and maltose content (raw vs. baked) were 'Gem', the sweetest, and 'Travis'. Correlation between sucrose index (SI) and AIS for baked samples was 0.956; for AIS and sweetness, correlation was -0.823. A similar correlation between the AIS and maltose was obtained for the data from the three harvests (-0.8493). Fifty volatile organic compounds of baked sweet potatoes were trapped in cold methylene chloride. The predominant volátiles were hexanal, 3-pente-2-ol, and isoledene. Other sweet aromas detected were 2,4-decadienal, 2-pentyl furan, benzaldehyde, 4-methyl-4-hydroxy-2-pentanone, and benzene acetaldehyde. The great differences in relative concentrations of volátiles among cultivars seem to be related to the synthesis of maltose and the content of AIS.


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