Tomato Pomace Research Articles

Sorption Isotherms and Drying Characteristics of Tomato Peel Isolated from Tomato Pomace

Tomato peel was separated from pomace by sedimentation and dried in cabinet and fluidized-bed dryer at 50–70°C using 4–12 kg/m2tray load. The drying of tomato peel took place under the falling rate period and the drying behavior was well described by Page's model with coefficient of determination greater than 0.99 and standard error of 0.003–0.016. A fluidized-bed dryer was much more efficient than a cabinet dryer to dry tomato peel. The moisture adsorption isotherms of tomato peel were obtained by equilibrating above saturated salt solutions of known a w (0.113–0.92) at 20–60°C. The data were analyzed using fifteen sorption models based on coefficient of determination, standard error, and residual plots. Modified Henderson was the best model for tomato peel with coefficient of determination >0.99, standard error <0.210, and a scattered residual plot. The net isostearic heat of sorption, estimated using the Clausius-Clapeyron equation, was 0.74–23.23 kJ/mol at 2.0–2.5% moisture content (dry basis).

Supercritical carbon dioxide extraction of carotenoids, tocopherols and sitosterols from industrial tomato by-products

In this work the supercritical carbon dioxide extraction of biologically active, high valued compounds such as carotenoids (lycopene, β-carotene), tocopherols, fatty acids and sitosterols from industrial tomato waste was investigated. The differences of two samples of different sources and the effect of air-dried and deep-frozen storages were also reported. The effects of extraction parameters (pressure and temperature) on the extraction yields and the compositions of the products were determined with statistical analysis. Supercritical fluid extraction was compared to conventional extraction processes of tomato pomace samples. The extracts were analysed by gas chromatography, by high-performance liquid chromatography and by TLC-densitometry. The extraction yields and the amounts of lycopene, tocopherols and sitosterols depend on the experimental conditions. The product obtained by supercritical CO 2 extraction at 460 bar and 80 °C contained the highest concentration of carotenoids with 90.1% of lycopene, while products rich in tocopherols and phytosterol were obtained above 300 bar and 40 °C.

Chemical characterization of tomato pomace

AbstractTomato‐processing by‐product, also known as tomato pomace, consists of peel and seeds and represents around 4% of the fruit weight. If these wastes remain unused, they not only add to the disposal problem but also aggravate environmental pollution. The aim of this paper is to evaluate the chemical composition of tomato pomace collected at different steps during industrial processing in order to assess the quality of this by‐product. Twenty‐one tomato pomace samples were considered for analysis. Samples corresponded to different steps during tomato processing for paste: seven after pulper, five after finisher, six before turbopress and three after turbopress. Samples were analyzed for moisture content, total and soluble sugars, protein, fat, soluble and total fiber, as well as mineral content. From the results obtained we can conclude that tomato pomace composition (in dry weight basis) is as follows: 59.03% fiber, 25.73% total sugars, 19.27% protein, 7.55% pectins, 5.85% total fat and 3.92% minerals. Copyright © 2006 Society of Chemical Industry

Feeding value of wet tomato pomace ensiled with wheat straw and wheat grain for Awassi sheep

In this study, two experiments were conducted to preserve tomato pomace (TP) by ensiling it with different levels of wheat straw (WS) and wheat grain (WG) to improve feeding value, digestibility, and acceptability of this source. Experiment I was arranged in a 3 × 4 factorial in which WS level (10, 15, and 20%) and WG (ground) level (0, 2, 4, and 6%) added to TP as wet basis and ensiled in 1 L jars. Effects of WS and WG addition on nutrient composition, pH value, Fleig points, and in vitro dry matter digestibility (IVDMD) of TP silages were investigated. In experiment II, three experimental silages were chosen among the twelve silages in experiment I for apparent digestion trial. These were 10% WS (I), 15% WS + 2% WG (II), and 15% WS + 4% WG (III) added TP wet basis and ensiled in 250 L barrels. In experiment I, when the level of WS increased, organic matter (OM), crude protein (CP), and IVDMD of TP silages decreased ( P < 0.05). In contrast, 4 and 6% WG addition increased OM, CP, and IVDMD of TP silage ( P < 0.05). While increasing the WS level increased neutral detergent fiber (NDF) and acid detergent fiber (ADF) content of TP silages, WG reduced NDF and ADF contents ( P < 0.05). Also, silage qualities of all TP silages were in very good quality according to the Fleig Point Scale. In experiment II, dry matter (DM), OM, CP, ADF, and NDF digestibility of silage I (10% WS) and silage III (15% WS + 4% WG) were found similar ( P > 0.05), but silage II (15% WS + 2% WS) had a lower DM, OM, CP, ADF, and NDF digestibility ( P < 0.05). Silage DMI was not affected by WS and WG addition to TP ( P > 0.05). As a result, ensiling TP with 10% WS can be a source of good quality roughage for sheep during the insufficiency periods of roughages.

Biochemical and molecular responses to antioxidant supplementation in sheep

The biochemical and molecular effects of tomato pomace (1.3% lycopene) or grape skin (87% polyphenols) supplementation for the control of hand-on induced stress in sheep were investigated. Twenty ewes were fed with a same basal diet for a preliminary period of 30 days and thus assigned to five groups: control group without any antioxidant (CTR); α-tocopherol (VIE, 100 mg/head/day); grape skin extracts (GRA, 5.5 g/head/day); tomato pomace (TOM, 10 g/head/day); tomato pomace and grape skins (TOG, 5.5 g/head/day of grape skins and 10 g/head/day of tomato pomace). Stress was administered by sampling blood at 0, 2, 3, 5, 7, 10 and 15 days after the beginning of the antioxidant administration. For the experiment, only samples at 0, 3 and 15 days were analysed. Plasma malondialdehyde (MDA), blood glutathione (GSx) and blood glutathione peroxidase (GPx) were not affected by dietary antioxidants, but significantly changed during the experimental period for all the sheep. A significant down-regulation of mRNA glutathione- S-transferase (GST) expression was observed 3 days after the addition of grape skins ( P = 0.006). After 15 days from the beginning of antioxidant administrations, the mRNA expression of cytochrome P450 (P450) showed a consistent reduction ( P = 0.011) in CTR, TOM and VIE groups, and superoxide dismutase (SOD) was up-regulated for TOG, GRA and TOM groups ( P = 0.000). Present results indicate that grape skins were more effective in inducing specific transcriptional activiy of genes involved in oxidant defences than tomato pomace and Vitamin E. The positive effect of Vitamin E is instead more evident in the short-term variations of GSx and GPx.

Effect of cultural conditions on xylanase production by Streptomyces sp. (strain Ib 24D) and its potential to utilize tomato pomace

The purpose of this study was to determine the effect of some cultural conditions on the xylanase enzyme production by Streptomyces sp. (strain Ib 24D) and to investigate its potential to produce xylanase utilizing tomato pomace as a substrate. Xylanase activity was detected using the dinitrosalicylic acid assay method. The crude enzyme was maximally active at pH 6.5 and 60°C. The maximal enzyme production was obtained when oat spelt xylan was used as a carbon source. When tomato pomace was used as carbon and nitrogen source, the maximal xylanase production was 1447 U/ml. SDS-PAGE and zymogram analysis revealed one band of 58 kDa with xylanolytic activity. The Streptomyces sp. (strain Ib 24D) was able to produce a considerable amount of xylanase with high levels of activity at a broad ranges of pH and temperature, in addition to its ability to utilize tomato pomace as a carbon and a nitrogen source.

Preliminary Study on Tomato Pomace as Unusual Feedstuff in Broiler Diets

The objective of this study was to evaluate the tomato pomace (TP) as unusual feed stuff in broiler diets in terms of growth, feed conversion ratio (FCR) and mortality. 300-day old Hubbard broiler chicks were weighed and randomly distributed into 4 groups with three replicates of 25 chicks each. Birds were fed four experimental diets in which the first was the control group (T1) and the other diets contained 10% alkali treated tomato pomace (T2), 10% heat-treated tomato pomace (T3) and 10% sun dried tomato pomace (T4). All diets were isonitrogenous and isocaloric. Feed and water were offered ad-lib during the experiment period. The results of this experiment showed that there were no significant differences (P<0.05) in live body weight due to feeding chicks diets containing TP. The only significant difference (P<0.05) was observed between the control group and those fed dietary treatments. Body weight gain had nearly the same trend as live body weight. Cumulative feed consumption was significantly (P<0.05) affected by feeding TP whe n compared with control group. There were no significant differences (P<0.05) in FCR of chicks fed different dietary treatments when compared with those fed control diets. Mortality rate was 3% during the whole experiment period, which is insignificant.

Flotation-cum-sedimentation system for skin and seed separation from tomato pomace

Skin and seeds were separated from the pomace in a newly designed and fabricated flotation-cum-sedimentation system consisting of one mixing tank, three settling tanks, a water-collecting tank and a recirculation pump. The dispersion time at various feed rates revealed that with the increase in pomace level from 5% to 20% the dispersion time also increased from 1.6 to 31.31 s. The system was operated at various feed (6–12 kg/min) rates and quality of the separated skin and seeds was evaluated. The separation efficiency increased from 58% to 71% for skin and 42% to 65% for seeds respectively as the feed rate varied from 12 to 8 kg/min. Results revealed that the system could be operated with a feed rate of 500 kg/h.

EFFECT OF TOMATO DECAY PROPORTION ON ERGOSTEROL LEVEL AND SOME TOMATO PULP PROPERTIES

ABSTRACT There is a need to develop a chemical method to determine the amount of decayed tomatoes used to produce tomato products. Tomato pulp samples produced from surface decayed tomatoes as sound, 30, 60 and 100% were tested for pH, brix, titrable acidity, Hunter L, a and b, Howard Mold Count (HMC) and ergosterol values. Tomato pomace for each decay portion was tested for HMC and ergosterol. Ergosterol analysis was carried out by high‐pressure liquid chromatography (HPLC). Decay proportion was linearly correlated with HMC (r = 0.97) and ergosterol (r = 0.96) in pulp samples but not to pH and acidity. Only ergosterol measurement was applicable in tomato pomace and correlated well (r = 0.95) with the decay proportions. In general, the color values of the samples produced from 100% decayed tomatoes were high compared with the others. The measurement of ergosterol has the potential to be used for the quality assessment of tomato products made from Red Top tomatoes.

Protective Role of Lycopene Against Diethylnitrosamine Induced Experimental Hepatocarcinogenesis

Lycopene was considered as a major carotenoid in the human diet for only the last few centuries. Recently lycopene has been found to possess chemoprotective effect against gastrointestinal tract, urinary bladder, prostate and breast cancers. In the present study, the protective effect of lycopene, the natural extract from tomato pomace against diethylnitrosamine (DEN)-induced hepatocellular carcinoma (HCC) formation in rats was investigated. Four groups of male albino rats at the age of 6 weeks were studied: 1) control (C), 2) DEN, i.p. injected 5 times with doses of 200 mg/kg b.w., one dose every two days. 3) Lycopene, orally given 0.12 mg/rat/day. 4) Lycopene + DEN, the treatment with lycopene started 7 days before DEN injection and continued till the end of the experimental period. Rats in group 2 and 4 were treated with Phenobarbital (PB) at a dose of 500 ppm in the drinking water as a tumor promoter. PB treatment started with the first injection of DEN and continued till the end of the experimental period. The results indicated that DEN caused HCC nodules as evidenced by a remarkable significant increase in α-L-fucosidase and metalloproteinases (MMPs) enzyme activity in both serum and cytosol. Increased activity of these enzymes is a marker for both preneoplastic and carcinoma lesions. Administration of lycopene prior to DEN injection protected rats from DEN-induced HCC as evidenced by a significant descent in α-L-fucosidase and MMPs enzymes activity in both serum and cytosol. The histological investigation of liver tissue confirmed these results. DEN group showed proliferated hyperplastic and anaplastic hepatocellular nodules surrounded with thin layer of fibroblastic cells, desmoplasia and inflammatory cells infiltrations, focal hepatic haemorrhages and necrosis. Meanwhile, lycopene + DEN group showed no histopathological changes. These results indicate that lycopene effectively inhibits DEN-induced hepatocarcinogenesis in rats.

Protective Role of Lycopene Against Diethylnitrosamine Induced Experimental Hepatocarcinogenesis

Lycopene was considered as a major carotenoid in the human diet for only the last few centuries. Recently lycopene has been found to possess chemoprotective effect against gastrointestinal tract, urinary bladder, prostate and breast cancers. In the present study, the protective effect of lycopene, the natural extract from tomato pomace against diethylnitrosamine (DEN)-induced hepatocellular carcinoma (HCC) formation in rats was investigated. Four groups of male albino rats at the age of 6 weeks were studied: 1) control (C), 2) DEN, i.p. injected 5 times with doses of 200 mg/kg b.w., one dose every two days. 3) Lycopene, orally given 0.12 mg/rat/day. 4) Lycopene + DEN, the treatment with lycopene started 7 days before DEN injection and continued till the end of the experimental period. Rats in group 2 and 4 were treated with Phenobarbital (PB) at a dose of 500 ppm in the drinking water as a tumor promoter. PB treatment started with the first injection of DEN and continued till the end of the experimental period. The results indicated that DEN caused HCC nodules as evidenced by a remarkable significant increase in α-L-fucosidase and metalloproteinases (MMPs) enzyme activity in both serum and cytosol. Increased activity of these enzymes is a marker for both preneoplastic and carcinoma lesions. Administration of lycopene prior to DEN injection protected rats from DEN-induced HCC as evidenced by a significant descent in α-L-fucosidase and MMPs enzymes activity in both serum and cytosol. The histological investigation of liver tissue confirmed these results. DEN group showed proliferated hyperplastic and anaplastic hepatocellular nodules surrounded with thin layer of fibroblastic cells, desmoplasia and inflammatory cells infiltrations, focal hepatic haemorrhages and necrosis. Meanwhile, lycopene + DEN group showed no histopathological changes. These results indicate that lycopene effectively inhibits DEN-induced hepatocarcinogenesis in rats.

Tomato pomace may be a good source of vitamin E in broiler diets

Dried tomato pomace, a byproduct of tomato processing, is an excellent source of $$alpha$$-tocopherol (vitamin E), which is used as an antioxidant in broiler meat. In a feeding study, there were no significant differences in body weight and feed per gain in chicks given diets with or without tomato pomace. Tomato pomace could be used as a source of $$alpha$$-tocopherol in broiler diets to decrease lipid oxidation (fat deterioration) during heating and long-term frozen storage of dark meat, and to prolong shelf life. Because tomato byproducts contain high levels of unsaturated fatty acids, the pomace must be defatted without losing vitamin E to minimize its oxidation potential. Although we found no evidence that introducing a high-fiber feed ingredient significantly limited broiler growth, more research is needed to enhance its practical applications.

EFFECT OF POMACE ADDITION ON TOMATO PASTE QUALITY

Tomato pomace obtained as a residue of tomato processing plants can be used to extract different compounds of high nutritional and economical values as oil, protein, fiber or lycopene that can be used in food industry. The objective of this work was to evaluate the effect of tomato pomace and peels incorporation into tomato concentrate. Peels and tomato pomace meal were added to four different tomato concentrate. Addition was made in four levels (1, 2.5, 5 and 10% w/w). Parameters evaluated in different samples were: Brix (soluble solids content), consistency (bostwick), total sugars, pectins, fiber, proteins, total fat and lycopene. Consistency of resulting products was measured by Bostwick method. After peels addition there was an increase on pectins and consistency (with 309.5 and 98.3%), meanwhile tomato pomace addition increased protein and total fat content (67.5 and 121.4%). From our results we can conclude that tomato concentrate quality (nutritional and technological) can be improved by tomato pomace addition.

Analysis of pendimethalin residues in fruit, nuts, vegetables, grass, and mint by gas chromatography.

Pendimethalin [N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine], in the formulation of Prowl (a commercial herbicide), was applied to various crops. Analysis of pendimethalin and its metabolite [4(1-ethylpropyl)amino-2-methyl-3,5-dinitrobenzyl alcohol] was accomplished by utilizing liquid-liquid partitioning, gel permeation chromatography (GPC) for nuts and mint, solid-phase extraction (SPE) cleanup, and gas chromatography (GC) with a nitrogen--phosphorus detector (NPD). Method validation recoveries for fruits, nuts, vegetables, grass, and mint are given for both compounds. Pendimethalin average recoveries ranged from 71% to 126% over two levels of fortification. Pendimethalin metabolite average recoveries ranged from 69% to 123% over two levels of fortification. The quantitation limit for all crops except mint was 0.050 ppm. The quantitation limit for mint and mint oil was 0.10 ppm. Residues greater than the limit of quantitation were found for pendimethalin in apple pomace, fresh and dry fig, grass screenings, mint oil, almond hulls, green onion, and tomato pomace (wet and dry). Residues greater than the limit of quantitation were found for pendimethalin metabolite in grass screenings, grass straw, and almond hulls. All other crop analyses for pendimethalin and its metabolite were below the limit of quantitation.

Utilisation of tomato pomace as a substrate for the production of vitamin B 12 – a preliminary appraisal

The cellulose fraction in tomato pomace was hydrolysed using Trichoderma reesei, and the resultant sugars were fermented with Propionibacterium shermanii to produce vitamin B 12. A multifactorial experiment revealed that aeration of the culture of T. reesei gave substantial improvements in cellulase activity as did higher concentrations of available nitrogen, but a rapid drop in pH appeared to inhibit extensive hydrolysis; after 14 days, the maximum level of cellulose degradation was only 34.4% of the total available, and the highest level of reducing sugars achieved was 15 g l −1. When flasks with the latter concentration of reducing sugars were inoculated with P. shermanii, 11.1 mg l −1 of B 12 were produced under optimum conditions. If the degree of hydrolysis of the cellulose could be increased, then sufficient vitamin B 12 might be generated to justify extraction but, even if purification does not prove to be economically feasible, a fermented tomato pomace (dried) with 50–55 mg kg −1 or more of B 12 could prove a useful feedstuff for animals.

Fruit and vegetable fiber fermentation by gut microflora from canines.

The objective of this study was to assess fermentability by canine gut microflora to include shortchain fatty acid (SCFA) production, organic matter (OM) disappearance, and gas production of vegetable and fruit fiber sources compared to fiber standards (psyllium, citrus pectin, and Solka Floc). Fiber sources included apple pomace, carrot pomace, flaxseed, fruit blend (mixture of peach, almond, nectarine, and plum), grape pomace, pea hulls, pistachio, and tomato pomace. Substrates were fermented in vitro for 4, 12, and 24 h with fecal flora obtained from three healthy dogs. Citrus pectin had the highest OM disappearance, SCFA production, and gas production at all times of fermentation; psyllium was intermediate and Solka Floc was lowest. A wide variation in fermentability was noted among the vegetable and fruit fiber sources. Apple pomace, carrot pomace, and flaxseed had the greatest fermentability as assessed by OM disappearance. Pea hulls and tomato pomace had intermediate OM disappearances, and fruit blend, grape pomace, and pistachio were poorly fermented. Carrot pomace produced the largest amounts of gas and SCFA. Apple pomace produced high concentrations of gas but intermediate concentrations of SCFA. Pea hulls and tomato pomace produced intermediate concentrations of gas and SCFA, whereas flaxseed, fruit blend, grape pomace, and pistachio produced low amounts of these fermentation products. For all substrates collectively, OM disappearance was highly correlated with both gas production (r2 = 0.782 and 0.723 for 12- and 24-h values, respectively) and SCFA production (r2 = 0.737 and 0.738 for 12- and 24-h values, respectively). In general, OM disappearance, gas production, and SCFA production were related to the insoluble:soluble fiber ratio in the samples; as the insoluble:soluble ratio decreased (increased soluble fiber), the OM disappearance, gas production, and SCFA production increased.

The effect of dried tomato, grape and apple pomace on the cholesterol metabolism and antioxidative enzymatic system in rats with hypercholesterolemia.

The effect of dried tomato, grape and apple pomace (5% in diet) on the cholesterol levels in serum and selected organs was studied in male Wistar rats fed a cholesterol diet (0.3%) shortly after weaning. Pomace of individual fruits contained 47.2, 67.0 and 46.2 g of total dietary fiber per 100 g of dry matter for tomato, grape and apple pomace, respectively. Corresponding values for the soluble components of the fiber were 10.3, 14.7 and 26.0%. None of the tested products affected the serum cholesterol levels. Tomato and apple pomace significantly reduced cholesterol level in liver by 15% and 11%, respectively, and all tested pomace species reduced cholesterol content in heart (by 18-21%). Triacylglycerol content was affected only by tomato pomace and solely in the heart. Cholesterol absorption measured by dual-isotope ratio method, was not significantly affected by the pomace, however, all products strongly reduced (up to the half of the original value) the activity of HMG-CoA reductase in liver and increased the fractional catabolic rate of plasma cholesterol (by 60-120%). All tested pomace reduced plasma levels of conjugated dienes and tomato and grape pomace exhibited this effect also in the liver. All tested pomace reduced the activities of antioxidant enzymes superoxid dismutase, catalase and glutathione peroxidase in erythrocytes (by 34-56%).

Wet Tomato Pomace Ensiled with Corn Plants for Dairy Cows

The fermentation characteristics and nutritive value of a mixture of whole corn plants and wet tomato pomace were studied. Laboratory silos were filled with mixtures of corn plant dry matter (DM) and tomato pomace DM in the following ratios: 100:0, 94:6, and 88:12. The initial pH of the mixtures decreased linearly as the amount of tomato pomace increased, but no treatment effects were found after 3 d of ensiling. At d 56, concentrations of lactic acid and nonprotein N (as a percentage of total N) decreased linearly as tomato pomace increased. Whole corn plants were chopped from a single field, mixed with 0 or 12% tomato pomace (percentage of DM), and ensiled in two concrete stave silos. The addition of tomato pomace increased concentrations of crude protein (7.6 to 9.8%), lignin (2.4 to 6.1%), and fatty acids (2.5 to 3.8%). Both silages were mixed into an isonitrogenous total mixed ration that contained 40% concentrate. The total mixed rations were fed to lactating dairy cows for 60 d. Milk production (35.5kg/d), milk composition, DMI (22.7kg/d), nutrient digestibility, and N balance were not affected by the addition of tomato pomace. Wet tomato pomace can be blended with corn plants before ensiling without greatly altering fermentation. The nutritional value of the mixture was equivalent to that of untreated corn silage.

Saccharification of tomato pomace for the production of biomass

Several cellulase titers were used to saccharify suspensions of tomato pomace in 300 ml shake-flasks. The sacharification of the substrate produced glucose at different initial rates from 1.8 g of reducing sugar kg −1 per enzyme unit (at 10 g of tomato pomace kg −1) to 36.1 g of reducing sugar kg −1 per enzyme unit (at 160 g of tomato pomace kg −1). Maximum concentrations of reducing sugars were observed in the experiments with 160 g of tomato pomace kg −1 producing hydrolysates containing 49.7 g of reducing sugars kg −1. The maximum yield was 31% (w/w) corresponding to a 76% (w/w) cellulose conversion. The saccharification of tomato pomace also yielded other monosaccharides with the following distribution: glucose, 76.6% (w/w), fructose, 11.2% (w/w); xylose, 7.5% (w/w) and cellobiose, 3.8% (w/w). Fungal cultures grown in tomato pomace syrups showed that the initial biomass of 2.02 g kg −1 increased exponentially after a 4 h lag phase to yield 9.02 g kg −1 at the end of 48 h. The uptake of glucose occurred at 0.64 g/lh. At the end of the fermentation the fungi had consumed 93.4% of the total sugar, displaying a biomass yield of 0.53 g/g. The glucose was totally consumed between 12 and 24 h fermentation and the fungal growth observed up to 48 h was due to xylose and fructose, which started to be used after 12 h.

PESTICIDE RESIDUES IN BEEF TISSUES FROM CATTLE FED FRUITS, VEGETABLES AND THEIR BYPRODUCTS

ABSTRACT Muscle, adipose, liver and kidney tissue samples were collected from cattle fed potato processing residue (n=20), apple pomace (n=20), pear pomace (n=10), cannery corn waste (n=20), cotton gin trash (n=20), tomato pomace plus almond hulls (n=16), dried grape solids (n=10) or dried citrus pulp (n=6) as well as from control cattle which were not fed fruits, vegetables or their byproducts (n=21). All adipose tissue samples (n=143), representative samples of the above feeds (n=24) and representative samples of muscle (n=35), liver (n=35) and kidney (n=35) tissues were assayed for acephate, benomyl, captafol, cypermethrin, folpet, azinphos‐methyl, captan, chlorothalonil, ethyl parathion, and permethrin. In 2,720 tests for the aforementioned oncogenic pesticides, eight tests were positive, but no residue amount that would be considered violative was detected. The only pesticide detected was benomyl and it was detected at nonviolative levels in the adipose tissue of cattle that had been fed either apple pomace or pear pomace.