Prolonged Storage Period Research Articles

Kinetic study of the effect of the osmotic dehydration pre-treatment with alternative osmotic solutes to the shelf life of frozen strawberry

Quality of frozen strawberry can significantly be improved by means of osmotic dehydration as a pre-freezing treatment. The objective of this work was to study the effect of osmotic pre-treatment with alternative osmotic solutes, oligofructose and a high DE maltodextrin, on the quality and sensory properties of frozen strawberry tissue. Vitamin C, colour, texture, drip loss after thawing and sensory characteristics of pre-treated and conventionally frozen samples were kinetically studied at isothermal conditions, and their temperature dependence was modelled by the Arrhenius equation. Dehydrofrozen samples exhibited a significantly improved vitamin C stability especially at temperatures, below −12°C. The cryostabilization result of the oligofructose could be related to the glass transition behaviour of the modified osmo-dehydrofrozen food matrix. Colour deterioration was more intense in the case of untreated frozen strawberry samples. Osmo-dehydrofrozen compared to conventionally frozen strawberry halves showed an improved firmness for prolonged storage period and less water loss during thawing maintaining the strawberry tissue integrity. Sensory evaluation confirmed a good organoleptic quality in osmo-dehydrofrozen strawberries. The shelf life of all samples was calculated based on vitamin C (30% loss) and colour (50% chroma index retention) kinetic study results.

Transient CFD modelling of low-temperature spontaneous heating behaviour in multiple coal stockpiles with wind forced convection

Spontaneous heating of coal stockpile has long been a thermal dynamic hazard during coal storage, processing, and transport. A transient non-equilibrium thermal CFD model has been developed to study the low-temperature self-heating behaviour of coal in multiple stockpiles under different prevailing wind conditions. Modelling results from the initial steady wind flow simulation indicate that a wake region can be induced on the leeward side of each coal stockpile. Pressure coefficient drops when the wind stream encounters or leaves a stockpile and the pressure coefficient profiles of multiple stockpiles tend to have more resemblance with a wider spacing. The first stockpile acts like a wind barrier to the adjacent stockpiles and the maximum temperature of it tends to be the first approaching the critical temperature. A ‘hot spot’ will develop and then migrate towards deep regions in each of these stockpiles that are loosely compacted under higher wind velocity conditions. Wind velocity and porosity of stockpile have significant influences on self-heating behaviour of the stockpiles and transport pattern of gaseous products liberated by coal oxidation. Compacting stockpiles from loosely packed scenario to slightly packed scenario might not be able to slow down the temperature rising rate at low-temperature range but could considerably minimize the volume of deteriorated coal. The highest temperature rising profiles of the stockpiles located in downwind side can approach to that of the first stockpile, particularly when they are more widely stacked. Stacking coal stockpiles as close as practically possible is recommended to maximise the “protection” of adjacent stockpiles but would cause undesirable accumulation of carbonic gases. Stockpiles in low height and gentle slope will have a prolonged safe storage period, especially for the first stockpile directly facing the wind direction. However, it may not slow down the self-oxidation process of the adjacent stockpile at very initial stage due to “weakened protection” of the first stockpile. This study has practical reference to coal industry especially where multiple coal stockpiles require to be constructed.

Evaluation of natural preservatives in combination with acid whey for use in fermented sausage

Natural antioxidant and antimicrobial systems are set to become an important component in food preservation methodology. The effect of alternative natural preservatives (Sinapis alba L.-M, Rosmarinus officinalis L.-R, Juniperus communis L.-J) in combination with acid whey (AW) was investigated after the ripening period (21d) and over a prolonged storage period of sausage. An antioxidant activity of extracts exercise was performed. The antimicrobial, oxidative stability and sensory properties of these natural preservatives were compared to curing-control (C). Significantly lower rancid odor and rancid flavor (1.48) were observed for R and M compared with the C sample. The low level of these attributes evidenced the antioxidant properties of the R sample, which confirmed the lower CD (~0.48-0.48 µmol mg−1) and TBARS values (~0.41-1.02 mg MDA kg−1) during sausage storing and the highest antioxidant activity against ABTS+ radicals (~85.45 %). Incorporation of acid whey with rosemary extract will give the product a threefold effect: high quality (sensory acceptance), healthy benefit (elimination of nitrite and nitrate from meat products) and safety (improved microbiological and oxidative stability).

Chemical Characterization of Beer Aging Products Derived from Hard Resin Components in Hops (Humulus lupulus L.).

The bitter taste of beer originates from resins in hops (Humulus lupulus L.), which are classified into two subtypes (soft and hard). Whereas the nature and reactivity of soft-resin-derived compounds, such as α-, β-, and iso-α-acids, are well studied, there is only a little information on the compounds in hard resin. For this work, hard resin was prepared from stored hops and investigated for its compositional changes in an experimental model of beer aging. The hard resin contained a series of α-acid oxides. Among them, 4'-hydroxyallohumulinones were unstable under beer storage conditions, and their transformation induced primary compositional changes of the hard resin during beer aging. The chemical structures of the products, including novel polycyclic compounds scorpiohumulinols A and B and dicyclohumulinols A and B, were determined by HRMS and NMR analyses. These compounds were proposed to be produced via proton-catalyzed cyclization reactions of 4'-hydroxyallohumulinones. Furthermore, they were more stable than their precursor 4'-hydroxyallohumulinones during prolonged storage periods.

The Inhibition of Maillard Browning by Different Concentrations of Rosmarinic Acid and Epigallocatechin-3-Gallate in Model, Bakery, and Fruit Systems.

Rosmarinic acid and Epigallocatechin gallate concentrations were studied as natural inhibitors of Maillard browning in glucose/glycine model systems, and in bakery rolls and applesauce. The concentrations of the inhibitors were varied to determine the highest level of inhibition without a pro-oxidant/browning effect. UV absorbance and gas chromatography/mass spec (GC/MS) with solid phase microextraction (SPME) sampling was used to study browning in the model systems. Hunter L*, a*, b* was used to analyze the color change results of the inhibitors on applesauce and bakery rolls. It was determined that a 1.0% solution of either antioxidant in the glucose/glycine system produced the greatest inhibition and a synergistic effect was not apparent when the two were combined. Inhibition of browning and a lack of synergy between the antioxidants were also determined in food systems consisting of applesauce and bakery rolls. GC/MS analysis of the model system revealed a high level of pyrazine formation in no-inhibitor control samples and the absence of pyrazines in inhibitor-containing samples. Natural browning inhibitors, that is Rosmarinic acid and Epigallocatechin gallate, can be added to food items to inhibit browning over a prolonged period of storage in order to increase product shelf stability. The concentrations of the inhibitors require optimization since a pro-oxidant effect and increased browning will occur at high levels.

Effect of Film Layers and Storing Period on the Fermentation Quality of Whole Crop Barley Silage

Dept. Animal bio, Chanbuk National University, Jeonju, 561-756ABSTRACTThis study was undertaken to characterize feed value and silage quality according to storage period and film layers for whole-crop barley silage. The crude protein(CP) content increased in all silage during the storage periods compared to those before silage,this content slightly increased over the prolonged storage period but it was not significant(p>0.05). Depending on the film layers of silage, 6 layers were higher than 4 layers. The neutral detergent fiber(NDF) and acid detergent fiber(ADF) contents also increased in all silage during storage periods compared to those before silage(P<0.05), but they were maintained at similar levels during the storage period. Depending on the film layers of silage, 6 layers were higher than 4 layers. The total digestible nutrients(TDN) content decreased in all silage during the storage periods. However, it was maintained at a similar level for the duration of each storage period. Depending on the film layers of silage, 6 layers were lower than 4 layers. The pH value was decreased during the prolonged storage period and depending on the film layers, 6 layers were lower than 4 layers.In the organic acid contents during the prolonged storage period, lactic acid increased, acetic acid was lower, and butyric acid was significantly higher(p<0.05). Depending on the film layers, 6 layers showed higher levels of lactic acid and lower levels of butyric acid(p<0.05). Therefore, these results showed that 6 layer wrapping was advantageous for long term storage of whole crop barley silage, while also indicating that it is desirable to use 4 layer wrapping within a six month period.(Key words :Whole crop barley, Storing period, Film layers, Fermentation quality)

The effects of UV radiation during the vegetative period on antioxidant compounds and postharvest quality of broccoli (Brassica oleracea L.)

In this study, the effects of supplementary UV radiation during the vegetative period on antioxidant compounds, antioxidant activity and postharvest quality of broccoli heads during long term storage was studied. The broccolis were grown under three different doses of supplementary UV radiation (2.2, 8.8 and 16.4 kJ/m2/day) in a soilless system in a glasshouse. Harvested broccoli heads were stored at 0 °C in modified atmosphere packaging for 60 days. The supplementary UV radiation (280–315 nm) during the vegetative period significantly decreased total carotenoid, the chlorophyll a and chlorophyll b content but increased the ascorbic acid, total phenolic and flavonoid contents of broccolis. All supplementary UV treatments slightly reduced the antioxidant activity of the broccolis, however, no remarkable change was observed between 2.2 and 8.8 kJ/m2 radiation levels. The sinigrin and glucotropaeolin contents of the broccolis were substantially increased by UV treatments. The prolonged storage period resulted in decreased ascorbic acid, total phenolic and flavonoid contents, as well as antioxidant activity. Discoloration of the heads, due to decreased chlorophyll and carotenoid contents, was also observed with prolonged storage duration. Glucosinolates levels showed an increasing tendency till the 45th day of storage, and then their levels started to decline. The weight loss of broccoli heads during storage progressively increased with storage time in all treatments. Total soluble solids, solids content and titratable acidity decreased continuously during storage. Titratable acidity was not affected by UV radiation doses during the storage time whereas soluble solids and solids content (dry matter) were significantly affected by UV doses. Supplementary UV radiation increased the lightness (L*) and chroma (C*) values of the broccoli heads. Pre-harvest UV radiation during vegetative period seems to be a promising tool for increasing the beneficial health components of broccolis.

Low Impedance Carbon Adhesive Electrodes with Long Shelf Life.

A novel electrocardiogram (ECG) electrode film is developed by mixing carbon black powder and a quaternary salt with a visco-elastic polymeric adhesive. Unlike traditional wet gel-based electrodes, carbon/salt/adhesive (CSA) electrodes should theoretically have an infinite shelf life as they do not dehydrate even after a prolonged period of storage. The CSA electrodes are electrically activated for use through the process of electrophoresis. Specifically, the activation procedure involves sending a high voltage and current through the electrode, which results in significant reduction of impedance so that high fidelity ECG signals can be obtained. Using the activation procedure, the ideal concentration of carbon black powder in the mixture with the adhesive was examined. It was determined that the optimum concentration of carbon black which minimized post-activation impedance was 10%. Once the optimal carbon black powder concentration was determined, extensive signal analysis was performed to compare the performance of the CSA electrodes to the standard silver-silver chloride (Ag/AgCl) electrodes. As a part of data analysis, electrode-skin contact impedance of the CSA was measured and compared to the standard Ag/AgCl electrodes; we found consistently lower impedance for CSA electrodes. For quantitative data analysis, we simultaneously collected ECG data with CSA and Ag/AgCl electrodes from 17 healthy subjects. Heart rate variability (HRV) indices and ECG morphological waveforms were calculated to compare CSA and Ag/AgCl electrodes. Non-significant differences for most of the HRV indices between CSA and Ag/AgCl electrodes were found. Of the morphological waveform metrics consisting of R-wave peak amplitude, ST-segment elevation and QT interval, only the first index was found to be significantly different between the two media. The response of CSA electrodes to motion artifacts was also tested, and we found in general no difference in the quality of the ECG signal between the two media. Hence, given that CSA electrodes are expected to have a very long shelf-life, with potentially less cost associated with their fabrication, and have ECG signal dynamics nearly identical to those of Ag/AgCl, the new electrodes provide an attractive alternative for ECG measurements.

Physicochemical Properties of Chilled Abalone as Influenced by Washing Pretreatment in Citric Acid Combined with High Pressure Processing

Abstract Citric acid pretreatment (2% and 4% citric acid) and high pressure processing (200–400 MPa for 3 min) were conducted to elucidate quality characteristics and shelf life of abalone during chilled storage. Physicochemical properties, total volatile basic nitrogen (TVB-N), and total viable count (TVC) were used as indicators of quality and the shelf life of abalone. Citric acid pretreatment caused a decrease in pH and lightness, and 4% citric acid pretreatment exhibited a positive effect on TVB-N and TVC. Pressurization suppressed the formation of TVB-N and the growth of TVC in abalone. However, excessive modification in physicochemical properties of abalone resulted from processing at a pressure higher than 300 MPa. To achieve microbial inactivation without severe modification in abalone quality, citric acid pretreatment with high pressure processing offered a potential advantage in maintaining characteristics of chilled abalone during prolonged storage period.

Developing pressure sensitive adhesive electrodes: preliminary results.

A mixture of carbon black powder, polar organo salt and a pressure sensitive adhesive (PSA) has shown to be able to collect skin bio potentials. Such PSA electrodes do not dehydrate even after a prolonged period of storage, which leads to a theoretically infinite shelf life. The PSA electrodes need to be electrically activated through electrophoresis. ECG data were simultaneously collected with PSA and Ag-AgCl electrodes from 5 healthy subjects. ECG morphology was almost identical for both media. Hence, given that PSA electrodes have an infinite shelf-life, potentially with less cost associated with their fabrication, and have ECG signal dynamics nearly identical to those of Ag-AgCl, the new electrodes provide an attractive alternative for ECG measurements.

Is Gene Transcription Involved in Seed Dry After-Ripening?

Orthodox seeds are living organisms that survive anhydrobiosis and may display dormancy, an inability to germinate at harvest. Seed germination potential can be acquired during a prolonged period of dry storage called after-ripening. The aim of this work was to determine if gene transcription is an underlying regulatory mechanism for dormancy alleviation during after-ripening. To identify changes in gene transcription strictly associated with the acquisition of germination potential but not with storage, we used seed storage at low relative humidity that maintains dormancy as control. Transcriptome profiling was performed using DNA microarray to compare change in gene transcript abundance between dormant (D), after-ripened non-dormant (ND) and after-ripened dormant seeds (control, C). Quantitative real-time polymerase chain reaction (qPCR) was used to confirm gene expression. Comparison between D and ND showed the differential expression of 115 probesets at cut-off values of two-fold change (p<0.05). Comparisons between both D and C with ND in transcript abundance showed that only 13 transcripts, among 115, could be specific to dormancy alleviation. qPCR confirms the expression pattern of these transcripts but without significant variation between conditions. Here we show that sunflower seed dormancy alleviation in the dry state is not related to regulated changes in gene expression.

Divergent selection for shape of growth curve in Japanese quail. 7. Effect of egg storage at high temperature on embryo development and hatchability

1. Hatching time, hatchability of fertile eggs and embryo mortality in relation to (1) physical quality of fresh eggs and (2) embryonic development during storage and incubation periods were analysed after egg storage for 1, 5 or 10 d at 30°C in the meat-type lines of Japanese quail, HG and LG, divergently selected for high and low relative weight gain between 11 and 28 d of age, respectively, and constant body weight at 49 d of age.2. In both lines, the increase of egg storage temperature from 12°C (standard level) to 30°C increased the egg weight loss during storage, shortened the incubation period and reduced the hatching success.3. Similar to standard egg storage temperature, LG quail hatched earlier than HG quail after egg storage at 30°C and early and late mortality of both lines increased with a prolonged period of egg storage. In contrast to the standard egg storage conditions, no line differences in hatchability were observed.4. The results did not identify a relationship between the decrease in hatchability or embryo viability and line differences in external egg parameters as well as any important role of undesirable changes induced by a high storage temperature on albumen viscosity.5. The pattern of embryonic death, low developmental rate of embryos and a dichotomy between the development of the extra-embryonic vascular system and the embryo itself during egg storage at high temperature implied that an insufficient nutrient supply in consequence of developmental delay could represent a key factor in increasing early and late embryo mortality.

Development and evaluation of honey based mango nectar.

Honey enriched mango nectar was prepared by using honey as sweetening agent because of its high fructose and glucose content and medicinal properties. The nectar having 20% pulp, 15°B TSS and 0.30% acidity was prepared, filled in pre-sterilized glass bottles, heat processed and stored up to 6months under ambient (13.3-26.3°C and 44.5-81.0% RH) and refrigerated (4-7°C and 73% RH) conditions. The honey enriched mango nectar could be stored for 6months at ambient temperature and low temperature storage conditions and only little changes in the quality parameters viz., TSS, titratable acidity, ascorbic acid, total and reducing sugars, carotenoids and hydroxymethylfurfural (HMF) were recorded as compared to sugar based nectar. These changes were more under ambient conditions than refrigerated and no microbial growth was found in nectars at fresh stage and during storage up to 6months. The hydroxymethylfurfural (HMF) content in the mango nectars increased with prolonged storage period. The mustard honey based mango nectar had the higher carotenoids content but this decreased (725.60-689.20mg/100ml) during storage up to 6months under ambient storage conditions, whereas the decrease was less under refrigerated storage conditions. Organoleptic quality score was higher in mustard honey based mango nectar (6.8) as compared to sugar based mango nectar under refrigerated conditions after 6months storage. The results indicated that the mustard honey based mango nectar stored at low temperature was acceptable with respect to colour, taste and overall acceptability without any microbial spoilage and could be marketed as health drink.

Effect of cold storage and 1-MCP treatment on ethylene perception, signalling and synthesis: Influence on the development of the evergreen behaviour in ‘Conference’ pears

To further understand the response of ‘Conference’ pears to 1-methylcyclopropene (1-MCP) treatment and their ability to restore ripening after prolonged periods of cold storage, fruit were treated with 0, 300nLL−1 1-MCP or 300nLL−1 exogenous ethylene plus 600nLL−1 1-MCP prior to storage. Changes in ethylene, ethylene precursors (ACC, MACC), ethylene-related enzyme activities (ACS, ACO) together with their transcript levels, and the expression of four ethylene receptors and one Raf kinase protein from the ethylene signalling pathway, were monitored before and after cold storage and during subsequent ripening at 20°C.1-MCP treatment acted on the ethylene pathway in two differentiated phases. In a first initiation occurring during cold storage, the 1-MCP treatment limited the up-regulation of both PcACS1 and PcACO1 observed in control fruit and promoted an up-regulation of PcETR1 leading to a complete inhibition of ACO activity during cold storage. These regulations resulted in fruit unable to produce ethylene upon removal and promoted the second phase (maintenance phase). This second phase was characterized by a down-regulation of PcACS1 and PcACS4 as well as PcACO1 together with a clear up-regulation of PcETR5 and better maintenance of PcCTR1 transcript levels, which were partially reversed with exogenous ethylene treatment. All these different regulations led in turn to a complete inhibition of the ripening processes, which may partially explain the occurrence of the evergreen behaviour in ‘Conference’ pear during shelf-life.

Effect of storage temperature and duration on germination of moringa seeds (moringa oleifera)

Storing moringa seeds soon after harvesting at a specific storage temperature and for specific storage duration may affect the seed quality and germination percentages of the seed. Thus, an experiment was carried out to determine the storage temperature conditions and storage duration that may be used by small holder farmers when storing moringa seed to achieve optimum germination percentages. The results of the study indicated that management of storage temperature and storage duration of seed has potential to improve the seed quality and germination percentage of moringa seed. Across all the treatments, the results suggest that the quality of the seed improves with prolonged storage period up until three months, thereafter the quality of seed decrease with storage time unless stored under low temperatures (10 0 C). Good germination results were achieved after storing the seeds at a storage temperature of 25 0 C (ambient temperature) for a duration of 60 days.

An in vitro study on the dimensional stability of a vinyl polyether silicone impression material over a prolonged storage period

A new elastomeric impression material, a vinyl polyether silicone, has been commercially introduced. Its dimensional stability at different pouring times has not been reported. The purpose of this study was to evaluate the dimensional stability of vinyl polyether silicone (VPES) impressions as a function of delayed-pouring time for up to 2 weeks after performing a recommended clinical disinfection procedure. The 3 medium-body impression materials tested were EXA'lence 370, Imprint 3, and Impregum Penta soft. Impressions of a cylindrical metal model, which served as a control, were made and poured in a Type V stone after being disinfected in 2.5% buffered glutaraldehyde solution. Die diameter and anteroposterior and cross-arch measurements on each cast were made and compared to direct measurements of the control with a digital micrometer. The linear dimensional changes were compared and analyzed by using the Mann-Whitney U test (α=.05). Considering the absolute values for the mean percentage dimensional change, VPES cast measurements were below 1.0% (P<.001), with the majority being minimal (≤0.34%) at all pour times. Measurements of the casts were larger than those of the control in all but one specimen. The percentage dimensional changes of the individual die diameters were higher than those of the anteroposterior and cross-arch linear measurements. Casts produced from VPES impressions had similar dimensional changes to those of VPS at 1 week of storage and similar changes to those of PE at 2 weeks of storage. The behavior of VPES impressions varied from being the most accurate at immediate-pour to gradually exhibiting higher dimensional changes as time progressed. Casts produced from a disinfected regular set VPES (EXA'lence 370 monophase) demonstrated excellent dimensional stability at different pour times and were comparable to the tested VPS and PE impression materials.

Application of Immobilized Pointed Gourd (Trichosanthes dioica) Peroxidase-Concanavalin A Complex on Calcium Alginate Pectin Gel in Decolorization of Synthetic Dyes Using Batch Processes and Continuous Two Reactor System

Ammonium sulphate fractionated pointed gourd (Trichosanthes dioica) peroxidase- concanavalin A (PGP-Con A) complex was entrapped into calcium alginate-pectin gel. Catalytic performance of immobilized PGP-Con A complex in dye decolorization was examined on repeated use and reusing after a prolonged period of storage. Immobilized and entrapped peroxidase preparation retained 59.6% of the original activity after a period of 50 d. Entrapped PGPCon A complex decolorized 91.2% and 82.1% of the initial color from DR19 and dye mixture [DR19+DB9] after 20 d, respectively. Considerable color removal was found even after 120 d and 80 d respectively, of operation of two reactor system and total organic carbon analysis was quite comparable to color loss. This study shows the efficacy, durability and sustainability of using immobilized T. dioica peroxidase in batch and continuous two reactor catalytic system for the removal of synthetic dyes from industrial effluents.

Anthocyanin Stability and Silage Fermentation Quality of Colored Barley

This study was conducted to observe the fermentative quality and anthocyanin content in whole crop colored barley silage during storage periods and anthocyanin stability in in vitro ruminal fluid. Silages of colored barley cultivar “Boanchalbori” and normal barley cultivar “Yuyeonbori” were stored during 0, 2, 4, 6, and 12 months. The in vitro ruminal fluid was fermented for 0, 6, 12, 24, and 48 hrs. For the feed value, crude protein of colored barley silage was slightly increased in the silage compared to that of normal barley silage, and being increased up to 2 months after ensiling and thereafter maintained at the similar level. Neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of both the barley significantly increased by prolonged storage of 2 months (p<0.05), but they were maintained at the constant level after 2 months of storing silage. Whereas TDN (total digestible nutrients) contents of them were decreased by the prolonged storage of 2 months (p<0.05), then maintained at the constant levels. The fermentative quality and pH values in both the barley silages were slightly decreased during the storage time. Lactic acid and acetic acid contents were increased during prolonged storage period, but not significantly different among treatments. Butyric acid was not detected. In the colored barley silage, pH value showed slightly lower compared to that of the normal barley silage but not significant, and lactic acid content was significantly higher than the normal barley silage (p<0.05). The total anthocyanin content in the whole crop colored barley silage decreased to 42% after 2 months of ensilage, however maintained at the constant level until 12 months of ensilage. In the case of anthocyanin stability on in vitro ruminal fluid digestion, the pH value of the ruminal fluid was slightly lower at 6, 12, 24, 48h incubation time and the content of anthocyanin was at similar levels. These results indicated that the colored barley showed higher fermentation quality, and total anthocyanin content was maintained stable at 42% level of the first value in storing silage. As the anthocyanin had higher stability in the ruminal fluid, the colored barley has a potential as functional feeds for Ruminants.

Effect of breed, age and storage period on egg weight, egg weight loss and chick weight of commercial broiler breeders raised in Saudi Arabia

A total of 1350 hatching eggs were obtained from commercial broiler breeders Cobb, Ross 308 and Arbor Acres at 30–35, 40–45 and 50–55weeks of age, 450 eggs for each breed and 150 eggs for each breed age. Eggs for each age were randomly divided into three groups, 50 eggs in each, stored either for 0, 7 or 14days, individually weighed before and after storage and incubated following usual hatchery practices. Individual chick weight was recorded at hatch and chick weight percent of fresh egg weight was calculated and data were statistically analyzed. Ross, young breeders and eggs stored for 14days had the lowest (P⩽0.05) egg weight whereas Arbor Acres, young breeders and hatching eggs stored for 14days showed the highest (P⩽0.05) egg weight loss percent. Cobb, old breeders and fresh hatching eggs had the highest (P⩽0.05) chick weight while Ross, old breeders and fresh hatching eggs showed the highest (P⩽0.05) chick weight percent of fresh egg weight.From the results of the study we conclude that there are significant breeds’ differences with respect to all studied traits. Arbor Acres was inferior to Cobb and Ross in most studied traits. The results also showed that advancing breeders’ age had a positive effect whereas prolonged egg storage period had a negative effect upon all studied traits.

Shelf life of rechargeable laryngoscope batteries without recharging

To the Editor, Proper laryngeal illumination is a crucial component of providing optimal conditions for tracheal intubation under direct laryngoscopy. Intubating equipment is often used and checked on a daily basis in the operating room; however, laryngoscopes often lie inactive for prolonged periods in emergency airway kits for the general wards, the emergency room, critical care units, or out-of-hospital use. Limited data are published on the life span of laryngoscope batteries or the safe storage period for emergency airway kits. We undertook to evaluate the useful ‘‘shelf life’’ of a commonly used laryngoscope device without battery recharging between uses. Institutional research ethics board approval was unnecessary for this simple bench test of a single laryngoscope to evaluate battery life between full charges. A new Heine 3.5 volt Xenon laryngoscope handle with a new nickel metal hydride (NiMH) battery and a new Heine Macintosh #3 Classic reusable fibreoptic stainless steel blade (Herrsching, Germany) was evaluated. The rechargeable battery was fully charged at the start of this study. The light intensity delivered from the handle and blade unit was tested daily using a previously described testing chamber and light meter. Light output was recorded after 30 sec of usage on each day (Figure). Testing was stopped on day 181 after the light output had dropped to 2,000 lux. This bench-top test shows that new NiMH battery sets can hold their charge for prolonged periods of time without requiring recharging. Testing was stopped arbitrarily once the light output had reached 2,000 lux as this is the threshold level that our institution had deemed as a minimum safe light requirement prior to introduction of the new International Organization for Standardization (ISO) guidelines of 500 lux. Our observations are limited by the fact that we tested a single new device with only one type of rechargeable battery (i.e., NiMH vs lithium or nickel cadmium batteries), and we did not examine battery ‘‘memory’’ effects. Despite these limitations, these observations over 181 days do help to characterize performance of these new laryngoscopes over prolonged storage periods under minimal usage conditions. These data should be useful to other institutions for equipment life cycle management and planning and for establishing quality control testing protocols for emergency airway equipment.