Sealed Polyethylene Research Articles

Fatty acids in carcass fat of steers treated with a β-adrenergic agonist individually or in combination with trenbolone acetate + oestradiol-17β

Forty steers of medium maturity were allocated randomly to four treatment groups of 10 steers each (C = Control, βA = β-Agonist, TO = Trenbolone acetate + oestradiol-17β and βTO = β-Agonist in combination with trenbolone acetate + oestradiol-17β). After 56 days on treatment, the β-Agonist treatment was stopped and the steers slaughtered on the ninth day after withdrawal. Samples of subcutaneous fat over the 13th rib and M. longissimus dorsi were stored in sealed polyethylene bags at −20 ° C for fatty acid analysis. A greater proportion of oleic acid ( C18: 1, P < 0.05) was deposited in the subcutaneous fat of steers treated with βA as opposed to those treated with either TO or βTO. Treatments altered the fatty acid composition of the M. longissimus dorsi, particularly through their effects on palmitic acid ( C16:0, P < 0.01), palmitoleic acid ( C16:1, P < 0.01) and oleic acid ( C18:1, P < 0.01). The results suggest a shift ( P < 0.01) towards saturated fatty acids in the M. longissimus dorsi of steers treated with either βA or βTO.

Problems in the Analysis of Cadmium in Autopsied Tissues

A comparison was made between the concentrations of Cd, Zn, Cu, and Fe in the organs at autopsy and after fixation in formalin for anatomicopathological examination. The concentrations of all the metals were lower in the formalin-fixed organs. In particular, the residual rates of Cd in the renal cortex and medulla were 2.3 and 6.1% of those for the fresh organs, respectively. The Cd concentration in the blood collected at autopsy was several hundred times as high as the value measured before death and failed to be an indicator of exposure to Cd. This phenomenon is specific to Cd and is not found with other metals. In determining Cd in the organs collected at autopsy, it is important to avoid contamination with blood, remove water around the organs quickly, and preserve the organs in sealed polyethylene bags.

In vitro degradation of wheat straw treated with neem ( Azadirachta indica) seed kernel cake water extract

The wheat straw was treated with different volumes of neem ( Azadirachta indica) seed kernel cake water extract (NSKCWE) for up to three weeks at ambient temperature in sealed polythene bags. There was a gradual increase in crude protein content with the increasing volume of extract in the premix and also with the increasing time of fermentation, in comparison to that of the control. The in vitro degradation study indicated that the total volatile fatty acids (TVFA) and in vitro dry matter digestibility (IVDMD) increased with the increasing volume of NSKCWE in the premix but decreased with the increase in the treatment period. The results showed that treatment of wheat straw with NSKCWE for the shortest time period (0 days) was the best among all the treatments.

Determination of cesium, rubidium and scandium in biological and environmental materials by neutron activation analysis

A simple method for the determination of cesium, rubidium and scandium in soil, vegetation and animal tissues by neutron activation analysis has been developed and evaluated. The methodology was designed to enable the comparison of fallout radiocesium from Chernobyl with stable elements in radioecological studies. Sample materials are dried and homogenized, and aliquots are irradiated, in sealed polyethylene vials (ca. 0.5 cm3), for 7 hours at a reactor flux of ca. 3·1012 n·cm−2·s−1. The activation products of interest have long half-lives, and are analyzed by high resolution γ-spectrometry after a cooling time of at least 12 days. The practical lower limits for determination of Cs, Rb and Sc are 3, 7 and 0.13 μg·kg−1 for soils and 10, 20, 0.4 μ·kg−1 for biological materials, respectively. Measurement of scandium levels in vegetation allows a straightforward correction to be made for soil contamination. Various applications to soil-grass-animal ecosystems are described.

Effects of modified atmosphere storage on banana postharvest diseases and the control of bunch main-stalk rot

Banana (Musa, AAA) bunch-sections consisting of one hand attached to a short section of main-stalk were wound-inoculated with cultures of fungi isolated from diseased fingers, crowns, or main-stalks and stored in sealed polyethylene bags containing 3–7% oxygen, 10–13% carbon dioxide and <0.1 μl l−1 ethylene for 40 days at 20°C, then ripened with ethylene in air for nine days. Colletotrichum musae, Fusarium moniliforme var. subglutinans and Nattrassia mangiferae caused high infection incidence in unripe fingers during storage. These fungi also caused crown rot, but only F. moniliforme var. subglutinans caused main-stalk rot. Alternaria alternata and F. pallidoroseum both caused some infection in unripe fingers during storage, and both subsequently caused crown rot. A. alternata also infected main-stalks. Lasiodiplodia theobromae and Phomopsis musicola infected only ripening fingers, and F. culmorum infected only crowns and main-stalks. The pathogenicity of some isolates was changed by interposing storage between inoculation and ripening. C. acutatum and C. gloeosporioides became unable to cause disease and F. culmorum caused less disease. In contrast, A. alternata and F. pallidoroseum became pathogenic to fingers, crowns and, in the case of A. alternata, to bunch main-stalks. Benomyl and prochloraz (500 mg l−1) controlled most diseases at inoculation sites, and naturally-occurring main-stalk rot. Prochloraz controlled more diseases than benomyl, and this control was usually more effective.

Moisture Affects Cowpea and Okra Seed Emergence and -Growth at Low Temperatures

The effect of moisture content on the emergence and development of `Pinkeye Purple Hull' and MN 13 cowpea [Vigna unguiculata (L.) Walp.] and `Clemson Spineless' okra [Abelmoschus esculentus (L.) Moench] seeds was investigated in a 3-year field study. Moisture content, ranging from 8% to 52%, was obtained by combining seeds, vermiculite, and varying volumes of water in sealed polyethylene packets and incubating them at 22C for 3 days. High moisture promoted the emergence of MN 13, did not significantly affect that of `Pinkeye Purple Hull', and decreased that of `Clemson Spineless' seeds. Percent seed emergence 22 days after planting averaged 17 % for `Clemson Spineless' and 15% for `Pinkeye Purple Hull' seeds, but was 44% for MN 13. High moisture generally promoted early harvest of MN 13 and increased root dry weight but did not affect fresh-pod yield significantly.

MODIFIED ATMOSPHERE PACKAGING OF BEDDING PLANTS AND PLUG SEEDLINGS

Poor post-production handling of bedding and seedling plants by mass-market outlets causes substantial quality reductions and product losses. Modified atmosphere packaging (MAP) may be a means to extend postharvest longevity and ease bedding plant handling. MAP, using heat sealed polyethylene bags, was tested with pansy, marigold, geranium, impatiens, California poppy, gazania, tomato, and pepper seedlings. Equilibrium O2 levels of 5-15% were generally reached within one to two weeks, while CO2 increased to 5% or more of the package atmosphere at equilibrium. Ethylene accumulated to more than .5ppm within 24 hours in some packages. Marigold seedlings had obvious leaf and stem distortion after 2-3 days. Maximum useful storage time varied from 2 weeks for tomato to greater than 8 weeks for pansy at 10C. Tomato and pepper seedlings were test marketed at a local supermarket.

Effect of storage and urea addition on detannification and in sacco dry matter digestibility of mature oak ( Quercus incana) leaves

Tannin levels as total phenols (TP), condensed tannins (CT) and protein precipitation capacity (PPC), in sacco dry matter digestibility (DMD) and cell-wall constituents were determined in leaves of Quercus incana stored under various conditions in sealed polythene bags. The rate and extent of both TP and CT inactivation were highest at 37°C, followed by 50°C and room temperature, on storage of whole fresh leaves containing 40% moisture. Storage of fresh leaves at 37°C after chopping increased these values. Increase of moisture to 55% at 37°C increased the rate and extent of tannin inactivation. The changes in PPC were similar to those for TP or CT. The relative degree of polymerisation increased two-fold on storage of leaves up to 45 days. In the second experiment, on ureaammonia induced inactivation of tannins in whole fresh leaves (moisture 55%, 30°C), the reduction in TP, CT and PPC increased as the level of urea increased. At 4% urea, the reduction in TP and CT was 88% and 100%, respectively, on Day 10. The level of neutral and acid detergent fibres and lignin increased gradually from Day 5 to Day 30 of storage in the absence of urea, whereas these changes were marked up to Day 5 and did not change appreciably from Day 5 to Day 30 in the presence of urea. The DMD decreased as storage time increased from Day 5 to Day 30. In the third experiment, whole fresh leaves with a moisture content of 55% and 4% urea were kept at room temperature and 30°C for 1–5 days only. The rate and extent of tannin reduction was lower at room temperature than at 30°C. The decreases in the values of TP, CT and PPC were 55%, 77% and 65%, respectively, at Day 1, and 72%, 89% and 83%, respectively, at Day 5, on storage at 30°C. The DMD did not change on storage up to Day 5. The results suggest that storage of oak leaves in the presence of 4% urea and high moisture could become a field method for inactivation of oak tannins.

Effect of various packaging materials on storage stability of refined, bleached, deodorized palm oil

Refined, bleached, deodorized palm oil (RBD palm oil) was packaged in lacquered metal cans (LMC), green glass bottles (GGB), amber glass bottles (AGB), clear glass bottles (CGB), clear plastic bottles (CPB) and sealed polyethylene film (POLET), and stored in direct sunlight (40 ± 1°C) or in darkness (27 ± 1°C). Measurements of free fatty acid (FFA), peroxide value and anisidine value, at 14‐day intervals for a period of 98 days, were used to assess the stability of the oil towards hydrolytic and oxidative deterioration. Total oxidation values for packaged oils stored in direct sunlight showed that LMC gave the greatest protection against oxidative deterioration, followed by GGB and AGB. POLET offered the least protection to the oil against oxidative deterioration, while CPB and CGB proved superior to POLET but inferior to GGB and AGB. For storage in the dark, LMC, AGB and GGB gave the greatest protection to RBD palm oil against oxidative deterioration, with no significant statistical differences between them, while CPB, CGB and POLET followed in that order, with significant differences between their respective abilities to protect the oil against oxidative deterioration. Oils packaged in CPB gave the highest FFA levels (statistically significant). The investigations clearly indicated that LMC is superior to all other tested packaging materials in offering maximum protection to RBD palm oil against hydrolytic and oxidative deterioration. Amber and green glass bottles could serve as viable alternatives to LMC, while CGB and CPB could be tolerated as suitable packaging systems for RBD palm oil. However, the study also clearly showed that POLET is unsatisfactory for use as packaging material for RBD palm oil.

Packaging systems for seafreight of broccoli

Abstract After 6 weeks storage at 1°C, the broccoli (Brassica oleracea) heads which were stored in unsealed polyethylene bags in waxed cartons without ice or in polystyrene boxes without the addition of ice (top ice) were still very fresh with green compact heads and no sign of microbial infection. The broccoli which was stored in unsealed polyethylene bags with ice or in polystyrene boxes with ice was not as good as those stored without ice. Ten—15% of broccoli was slightly mouldy and some soft rots were observed in iced treatments. Growth of micro-organisms was associated with the presence of free water in the packages after the melting of the ice. Chlorine treatment (250 ppm) controlled the mould in storage without ice, but had no effect in treatments with ice. The quality of broccoli which was stored in sealed bags (modified atmosphere (MA) storage) was as good as those stored in waxed cartons with unsealed polyethylene bags. The use of a polystyrene box with top ice for broccoli is not necessary if the temperature during storage and transportation can be maintained below 2°C. Irrespective of packaging, all the broccoli turned yellow and became unmarketable after transfer and storage for 2 days at 26°C, 70–75% RH, except those stored in sealed polyethylene bags under MA condition. The broccoli which was stored in sealed high density polyethylene bags was still fresh and green with compact heads and free of offensive odours. However, that stored in sealed low density polyethylene bags was also green, but some rots and off-odours were present.

Cast metal resin-bonded dental restorations: Effect on the resin-to-metal bond of storage conditions before cementation

Cast metal resin-bonded restorations are often stored in the laboratory or dental practice/office before they are fitted in the mouth. This study investigated the effect of the storage conditions of such restorations on the tensile bond strength of a resin cement. Sixty cylinders were cast in nickel-chromium alloy (Wiron 88). Their bonding surfaces were sandblasted, cleaned ultrasonically in distilled water, and air dried. Groups of 10 cylinders were stored for 10 days in an office environment as follows: in an open container, in a sealed polyethylene bag, in a plastic pot, in distilled water, or in acetone. A control group was used immediately for bonding. Each cylinder was bonded with a thin film of resin (Panavia Ex) to a freshly prepared disk of the same alloy. After 24 hours in water at 37 °C, the assembly was loaded under tension to failure. The results indicated that storage in an open container should be avoided and that restorations can best be protected by storage in distilled water.

Effect of ethylene absorption on the storage of Granny Smith apples held in polyethylene bags

Granny Smith apples grown in Western Australia are highly susceptible to the physiological disorders bitter pit and superficial scald, after short periods of storage. Granny Smith apples were held in sealed polyethylene bags with and without an ethylene absorbent Purafil (potassium permanganate on aluminium oxide). In two seasons the ethylene levels were markedly reduced with the use of potassium permanganate while the severity of bitter pit and superficial scald were also reduced. These effects of ethylene removal may be due to the delaying of fruit senescence.

Storage of banana bunches in sealed polyethylene tubes

Bunches of banana cv. Williams were obtained on seven occasions over a two year period from Coffs Harbour, New South Wales and treated with 0.1% benomyl to reduce rotting. Treatments were randomly applied to the bunches as follows: (I) No treatment, (II) Sealed in a polyethylene tube (thickness 0.1 mm), (III) Sealed in a polyethylene tube (thickness 0.1 mm) containing 100 g vermiculite impregnated with a saturated solution of potassium permanganate to remove ethylene. The bunches were held on each occasion at either 28, 20 or 13°C. The average storage life was increased 2-3 times (over control) when the bunches were held in sealed polyethylene tubes and increased 3-4 times when an ethylene absorbent was packed with the bunch in the polyethylene tubes. The use of the sealed polyethylene tubes and ethylene absorbent allowed a storage life of up to six weeks at 20-28°C and 16 weeks at 13°C. The storage life of the bunches was limited by the presence of high concentrations of carbon dioxide and/or ethylene in...

Absorption of DDT and HCH residues by wheat during storage in rural houses treated with these insecticides for malaria control

Wheat kept in gunny bags of 20 kg capacity in rural houses sprayed with DDT or HCH for mosquito control was found to acquire the residues of these insecticides up to 4.40 or 22.14 mg kg −1, respectively, during an 8 month storage period. Wheat stored in sealed polyethylene bags of 20 kg capacity also absorbed residues of these insecticides up to 3.17 and 14.12 mg kg −1, respectively. Samples kept in gunny or polyethylene packets of 100 g capacity absorbed DDT and HCH residues at levels higher than those kept in bags of 20 kg size. This may be due to their relatively large surface area available for exposure to the ambient environment. Absorption of residues of DDT and HCH by wheat stored in sealed polyethylene bags suggests that considerable transference of these insecticide residues can occur through vapour phase. Thus, the potential exists for the contamination of food commodities with substantial amounts of residues during their storage in rural premises treated with insecticides for malaria control and this may have significant implications in the regulation of insecticide residues in foods.

EFFECT OF MOISTURE CONTENT AND STORAGE TEMPERATURE ON THE VIABILITY OFBAMBUSA TULDASEED

SUMMARY Bamboos are attractive plantation species but as seed is only available in quantity during sporadic periods of gregarious flowering it is important to develop effective storage techniques. Tests with 3 incubation temperatures and 4 substrata showed the optimum conditions to evaluate viability involved germination at 30°C between two layers of paper. Seeds stored at their original moisture content of 26% lost germination capacity within 2 months but when moisture content was reduced to 10.2% and 6.6% percentage germination after 12 months was 57% and 70% respectively. Seeds stored in perforated polythene bags failed to retain germination capacity for 12 months at all tested temperatures. Storage in sealed polythene bags at ambient room temperature, 5°C, 15°C and 30°C gave percentage germinations of 70%, 80%, 82% and 24% respectively. The seeds exhibited orthodox behaviour and could possibly be stored for longer durations with proper handling and drying techniques.

青ウメの常温貯蔵におけるエチレン除去剤とポリエチレン密封包装の影響

The effects of packaging with polyethylene bags and the inclusion of ethylene absorbent and/or CO2 absorbent on the keeping quality of mume (Japanese apricot) fruits were investigated. Concurrently, the concentrations of oxygen, carbon dioxide, ethylene, ethyl alcohol, and acetaldehyde in the bags and their production by the fruits were monitored.1. Yellowing and softening of green mume fruit were noticeably retarded by the combination of packaging with polyethylene bags (0.02 mm) and the inclusion of an ethylene absorbent. This retardation of the ripening process was reversed when a carbon dioxide absorbent was included.2. The inclusion of ethylene absorbent in the bags kept ethylene concentration at very low level, whereas oxygen concentration was higher and carbon dioxide concentration lower compared with bags in which the absorbents were omitted. In sealed bags with carbon dioxide absorbent or without both absorbents, acetaldehyde and ethyl alcohol accumulated, resulting in a physiological disorder known as internal browning. Addition of the ethylene absorbent suppressed the accumulation of both volatiles and prevented the occurrence of the internal browning. Inclusion of carbon dioxide absorbent with ethylene absorbent negated the beneficial effect of the latter and resulted in the accumulation of volatiles which induced the physiological disorder.3. The respiration rate of the fruit was slower in sealed polyethylene bags with ethylene absorbent than in that without the absorbent; this suppression of respiration was overcome by the inclusion of the carbon dioxide absorbent. The ACC (1-aminocyclopropane-1-carboxylic acid) content in the fruit changed, parallelling the trends of ethylene evolution in all treatments. Among the different treatments, the ethylene forming enzyme (EFE) activity was lowest in fruits sealed in polyethylene bags containing the ethylene absorbent.

Optimising P2O5 availability for fertilizer use, by direct treatment of apatite with hydrochloric or nitric acids

Hydrochloric and nitric acid treated apatite is not directly used as a fertilizer because of the hygroscopic character of the products. Another problem arises from the volatility of these acids and that acidulated product undergo reversions during drying with loss of the acid. We have found that apatite beneficiated with hydrochloric and nitric acids dried at an optimum temperature ~120°C has high available phosphorous. The products can be stored in the solid form in sealed polythene bags.

Effect of calcium hydroxide or urea treatment of barley straw on intake and digestibility in sheep

Three experiments were undertaken with 7 to 8-month-old Suffolk cross Mule lambs weighing 35 kg (Experiment 1) and 29 kg (Experiments 2 and 3). Rations of restricted concentrates (176 g dry matter (DM)/day, Experiment 1; 142 g DM/day, Experiments 2 and 3), and ad libitum straw (Experiments 1 and 2) or restricted straw (Experiment 3) were fed over 35 days per experiment to measure intake (10 days) (Experiments 1 and 2) and digestibility (8 days faeces collection). Chopped straw was mixed with Ca(OH) 2 and/or urea dissolved in 0.8 1 water/kg straw. Treated straw (500 g DM/kg) was stored (56 days at 9.4°C in Experiment 1; 60 days at 9.6°C in Experiments 2 and 3) in sealed polythene bags before feeding. In Experiment 1 with 8 lambs/treatment, daily intakes of digestible straw organic matter per kg live weight (g DOM/kg W day −1) were: untreated straw, 5.7; 30 g urea/kg straw DM, 5.8; 30 g urea and 30 g Ca(OH) 2/kg straw DM, 6.9; 30 g urea and 60 g Ca (OH) 2, 8.7; 60 g urea and 60 g Ca (OH) 2, 9.4. In Experiment 2, using 48 lambs, straw intakes were higher. Intakes of g DOM/kg W day −1 were: untreated, 8.0; 60 g Ca(OH) 2, 11.2; 15 g urea and 60 g Ca(OH) 2, 12.2; 30 g urea and 60 g Ca(OH) 2, 13.7. In Experiment 3, using 12 lambs/treatment, with straw intakes at 13.7 g organic matter (OM)/kg W day −1, straw OM digestibilities (g/kg) were: untreated, 485; 60 g Ca(OH) 2, 575; 15 g urea and 60 g Ca (OH) 2, 585. No mold was encountered in any treated straws. Treatment with 30 g urea and 60 g Ca (OH) 2 was considered optimum as it maximised intake of digestible straw. An unexpected finding was that urea hydrolysis during storage was reduced in the presence of Ca (OH) 2.

Relationship Between Storage and Germinability of Cardamom (Elatteria cardamomum Maton)

AbstractCardamom seeds are considered recalcitrant, with relatively low retention of germinability during storage. Thus, a study tested the effects of drying temperatures on moisture loss and reduction in germinability of cardamom seeds. In addition, the effect of storage material and temperatures on retention of germinability was evaluated. The mature seeds of cardamom contained a high percentage of water at harvest, and germinability at harvest was around 62 %, confirming the recalcitrant nature of the seeds. Seed germinability was completely lost at moisture levels below 50 % (dry wt. basis) and higher temperatures reduced moisture levels and germinability faster. Drying at 20°C retained some degree of germinability for 7 days. In terms of storage, sealed polythene containers and low temperature (5°C) was optimal for maintaining some degree of germinability of cardamom seeds during storage for approximately 15 days.

Studies on the nutritional improvement of sorghum stover (Jowar Kadbi) through ammoniation by urea ensiling

Sorghum stover was ensiled with five levels of urea (0, 2, 4, 6 and 8%) at about 50% moisture level in sealed polythene bags for 0, 15, 30 and 45 days. The crude protein content increased immediately after treatment but slightly decreased after 15 days, remaining almost stable thereafter. The rumen disappearance of crude protein determined by nylon-bag technique was highest in the 8% urea group and it was almost similar after 30 days of ensiling. The ruminal disappearance of fibre fractions significantly increased at 4% urea and 30 days ensiling. Further increase in the urea level and ensiling period did not bring about a tangible increase.