Different Concentrations Of Sugar Research Articles

Low‐field nuclear magnetic resonance relaxometry: a new approach for monosaccharide identification in sugar solutions

SummaryMonosaccharides such as glucose, fructose, and galactose are the building blocks of oligosaccharides and act as the major energy sources in our body. These three monosaccharides are the most prominent in food processing and widely consumed analytes, found in fruits or milk. Although several analytical methods are available to identify and quantify sugar solutions, their drawbacks urge the search for better possible alternatives. A simple, rapid, and efficient method for identifying monosaccharides (ᴅ‐fructose, ᴅ‐galactose, and ᴅ‐glucose) was investigated using low‐field nuclear magnetic resonance (LF‐NMR), exploring the applicability and reliability of this machine. The transverse (T2) relaxation curve was analysed to distinguish monosaccharides from each other. The increasing monosaccharide concentration in the sugar solution causes leftward shifts in signals, indicating a gradual reduction in the mobility of water molecules. The addition of sugar generated a secondary peak, which assisted in identifying monosaccharides. Notably, fructose exhibited distinct behaviour from that of glucose and galactose. The regression coefficient consistently exceeded 0.98, indicating the reliability of this experiment. LF‐NMR encountered challenges in differentiating stereo‐isomeric glucose and galactose. However, quantification of monosaccharides from known binary mixtures (water and one monosaccharide) is possible by preparing standard curves of different concentrations of sugars. These standard curves can be either T2 or the total surface area of the peaks as a function of sugar concentration. The study concludes that LF‐NMR has potential for the qualitative and quantitative analysis of monosaccharides in pure solutions or powdered samples. It is hoped that the rapid and easy way of monosaccharide identification by simple analysis of peaks obtained from NMR spectra will enhance its accessibility for users. However, it also acknowledges limitations in applying this method to complex systems (mixtures of different sugars in a solution).

The Development of an Improved Medium for the In Vitro Germination of Corylus avellana L. Pollen

The European hazelnut (Corylus avellana L.) is a self-incompatible, wind-pollinated species of significant economic-productive interest, mainly cultivated between the Mediterranean basin and the Black Sea. Hazelnut breeding programs and high cropping in commercial orchards are necessarily linked to the availability of fertile pollen with wide germinability and high viability. The objective was to develop an improved method to determine the germinability of pollen, comparing the results with those found in the literature. Pollen germinability was firstly evaluated on a wild-type accession using boric acid (H3BO3), calcium nitrate (Ca(NO3)2), magnesium sulfate (MgSO4), potassium nitrate (KNO3), casein hydrolysate and different concentrations of sugars, including sucrose (10, 15 and 25%) and two monosaccharides, glucose (15%) and fructose (15%). The optimal composition included 15% sucrose in a semi-solid medium composed of 1% animal gelatin, containing collagen. This formulation was then tested on three cultivars of commercial interest, evaluating the effect of different concentrations of sucrose. The comparison between different in vitro germination methods showed that the hanging drop technique in a semi-solid medium provides a statistically higher germination index compared to the liquid and solid/agarized techniques. This study proposes an easy-to-use medium for the in vitro germination of Corylus avellana L. pollen.

Evaluating the use of cinnamon-water extract as taste modifier in yoghurt drink by temporal dominance of sensation

Development of low sugar food product has become a trend in food industries as the increase of diabetic prevalence. Cinnamon (Cinnamomum burmannii) has the potential to be used as a yoghurt drink taste modifier that expected to reduce sugar application. The goal of this study was to obtain the sensory attribute profile of cinnamon yoghurt drink with different concentrations of sugar and cinnamon, and evaluate the ability of cinnamon as sweet and sour taste modifier in yoghurt drink. This study involved 11 trained panelists to describe the sensory attribute profile of cinnamon yoghurt drink using the temporal dominance of sensations (TDS) method with 3 different concentrations of sugar (7,5%; 10%; and 12,5%) and cinnamon (0%; 5%; and 10%). It is important to note that the increase of cinnamon tended to suppress the sourness instead of enhancing the sweetness. Thus, it will lead to further sugar reduction application.

THE INFLUENCE OF SUGAR CONCENTRATIONS (GLUCOSE, SUCROSE) IN GRAIN AND BEET MOLASSES ON THE GROWTH OF CONDITIONALLY PATHOGENIC BACTERIA

Technologists of livestock complexes face the task of finding a carbohydrate feed supplement that would compensate for the energy deficit in the main diet. Grain and beet molasses meet this requirement. However, being a nutritious substrate, it can be actively colonised by environmental bacteria. The research aims to assess the influence of different concentrations of sugars from grain (glucose) and beet (sucrose) molasses on the development of conditionally pathogenic microorganisms. As a result of studying the effects of sugars from grain (glucose) and beet (sucrose) molasses at concentrations ranging from 18.0 to 46.0%, a preservative (antibacterial) effect against different bacterial species was observed. Glucose at 18.0–30.0% reduced the growth of L. mesenterioides, Ps. aeruginosa, Ps. fluorescens, E. coli, Str. viridans, L. monocytogenes, S. enterica subsp. houtenae, St. aureus, B. cereus by 2 to 5 orders of magnitude compared to the control; for certain species, concentrations of 22.0–30.0%, and for all species, concentrations of 34.0–46.0% were bactericidal. Sucrose at concentrations of 18.0–38.0% reduced the growth of certain species by 1–4 orders of magnitude compared to the control; the preservative (antibacterial) effect was observed at concentrations of 18.0–34.0% for certain species and at concentrations of 38.0–46.0% for all bacteria (except L. mesenterioides). Based on the results obtained, when not using chemical preservatives and disinfectants, it is advisable to manufacture grain molasses shortly before adding it to the animal's diet, as it is more technologically feasible. In this case, facilities for producing feed molasses can be located in the feed preparation department of any livestock complex, reducing the risks of possible contamination and reducing carbohydrate (sugar) content during longdistance transportation and storage.

Effect of addition of sugar and non-dairy creamer on sensory acceptance, physical properties, and antioxidant activity of sorghum-adlay milk

The popularity and demand of alternative beverages made from plants have gained attention over the last year due to health reasons. Cereal plants such as sorghum (Sorghum bicolor L.) and adlay (Coix lacryma-jobi L.) can be utilized as raw materials for the production of plant-based milk. However, information on the development of sorghum-adlay milk is still limited, especially regarding the ingredients used and their influence on the characteristics of the final product. The aim of this research was to investigate the effect of sugar and non-dairy creamer (NDC) addition on the sensory acceptance, color, physical stability, total soluble solids, pH, and antioxidant activity of sorghum-adlay milk. There were 15 samples formulated with different concentrations of sugar (4-20%) and NDC (0-2%). The results showed that samples with 20% sugar and 2% NDC had the highest sensory acceptance by the panelists. The addition of NDC significantly influenced the color of samples, which increased the L* value and decreased the a* and b* values (p<0.05). It also increased the total soluble solids and physical stability of the product (p<0.05). A higher concentration of NDC in the product could decrease the antioxidant activity of the alternative milk (p<0.05).

Prediction of Honeydew Contaminations on Cotton Samples by In-Line UV Hyperspectral Imaging

UV hyperspectral imaging (225 nm-410 nm) was used to identify and quantify the honeydew content of real cotton samples. Honeydew contamination causes losses of millions of dollars annually. This study presents the implementation and application of UV hyperspectral imaging as a non-destructive, high-resolution, and fast imaging modality. For this novel approach, a reference sample set, which consists of sugar and protein solutions that were adapted to honeydew, was set-up. In total, 21 samples with different amounts of added sugars/proteins were measured to calculate multivariate models at each pixel of a hyperspectral image to predict and classify the amount of sugar and honeydew. The principal component analysis models (PCA) enabled a general differentiation between different concentrations of sugar and honeydew. A partial least squares regression (PLS-R) model was built based on the cotton samples soaked in different sugar and protein concentrations. The result showed a reliable performance with R2cv = 0.80 and low RMSECV = 0.01 g for the validation. The PLS-R reference model was able to predict the honeydew content laterally resolved in grams on real cotton samples for each pixel with light, strong, and very strong honeydew contaminations. Therefore, inline UV hyperspectral imaging combined with chemometric models can be an effective tool in the future for the quality control of industrial processing of cotton fibers.

Standardization of Rose Apple (Syzygium jambos) Syrup with Different Concentrations of Sugar

The experiment was conducted on “Standardization of rose apple (Syzygium jambos) syrup with different concentrations of sugar” during the period November 2021 to February 2022 at Post Harvest Technology Laboratory, Department of Horticulture, Naini Agricultural Institute, Sam Higginbottom University of Agriculture Technology and Sciences, Prayagraj (Uttar Pradesh). The experiment was planned in completely randomized block design, seven treatments with three replication. The observations were recorded on various characteristics like acidity, TSS, pH, ascorbic acid content and organoleptic qualities. The results obtained from the experiment shows that the treatment T6 (rose apple juice + 55% sugar syrup) was found best in terms of the quality attribute as compared to other treatments. It shows the highest mean score in sensory evaluation like colour and appearance (8.85), taste (8.6), aroma (8.45), overall acceptability (8.7) and the chemical parameters like titratable acidity (0.458), T.S.S (64.66˚Brix), pH (4.427) and ascorbic acid (26.73%). Therefore on the basis of above findings it is concluded that the treatment T6 (rose apple juice + 55% sugar syrup) is the most promising and best syrup in terms of their physico-chemical and organoleptic test of rose apple syrup.

Standardization of Pineapple Wine by using Different Concentration of Sugar (Ananas comosus L.)

The study was conducted in Completely Randomized Design (CRD) with 5 treatments & four replications. The treatments were T1 (pineapple juice (700ml) + Beetroot extract (35gm) + 20° brix + Beetroot extract (35gm) wine yeast (0.133%), T2 (pineapple juice (700ml) + Beetroot extract (35gm) + 25° brix + wine yeast (0.133%), T3 (pineapple juice (700ml) + Beetroot extract (35gm) + 30° brix + wine yeast (0.133%), T4 (pineapple juice (700ml) + Beetroot extract (35gm) + 35° brix + wine yeast (0.133%), T5 (pineapple juice (700ml) + Beetroot extract (35gm) + 40° brix + wine yeast (0.133%) Total soluble solids, pH and Specific Gravity decreased while the alcohol content, Acidity and the Sensory Qualities increased with increasing length of fermentation. From the above treatments, it is concluded that treatment T4 was found superior in respect of the parameters like Total Soluble Solids, Acidity, pH, Alcohol content, Specific gravity. With respectively Color and Appearance, Taste, Aroma and Overall acceptability also T4 was found best. In terms of economical evaluation, Net return and cost benefit ratio was found best in treatment T4. Since Pineapples contains good sugar proportion which makes it suitable for wine making, while beetroot contains huge amounts of biologically active substances and commonly used in manufacturing as a food coloring agent, the production of wine from this fruit can help increase wine variety and reduce post-harvest losses. This study showed that acceptable wine can be produced from pineapple using yeast especially Saccharomyces cerevisiae.

Determination of the antimicrobial activity of lactic acid bacteria isolated from the Black sea mussel Mytilus galloprovincialis Lamarck, 1819

The present study reports on the determination of the antimicrobial activity of lactic acid bacteria (LAB) isolated from the Black sea mussel Mytilus galloprovincialis Lamarck, 1819. The samples were collected in the period of August 2018 until March 2021. The BIOLOG system was used for microbiological determination. From the mussel M. galloprovincialis Lam. four species of LAB were isolated - Sporolactobacillus kofuensis, Lactobacillus sakei, Streptococcus gallolyticus ss gallolyticus and Lactibacillus brevis. The activity of the strains was determined against test cultures (Escherichia coli 3398, Staphylococus aureus 745, Bacillus subtilis 6633, Salmonella typhimurium 3591, Listeria monocytogens 863 Enterobacter aerogenes 3691, Aspergillus niger, Penicillium claviforme, Saccharomyces cerevisae, Candida albicans 8673 and Candida glabrata 72). Before the analysis for antimicrobial activity, the LAB were cultured in media with different concentrations of sugars - 2, 5 and 10%. The results showed that 4 strains S. kofuensis, L. sakei, S. gallolyticus ss gallolyticus and L. brevis cultured on glucose and oligosaccharides completely lost their activity in all studied variants. Therefore, some carbohydrates (glucose) and oligosaccharides induce the synthesis outside the cell of biologically active molecules, which can probably be attributed to peptides/proteins.

Effects of sugar addition on adipolysis and volatile profiles of dry cured sausage

As sugar play a primary role in food flavor and biochemical reaction during the industrial manufacture of dry cured meat products, we aim to evaluate the function of sugar and how the quality changed with the addition of sugar on dry cured sausage after three months of preservation, and the corresponding effect on acidity value and the total acid value. The roles of sugars’ effects on FA hydrolysis and flavor formation are required to be assessed. We selected the addition of sugar with the gradient contents from 3% to 15%, we found that the total acid, acidity value, peroxide value, FA and organic acid were significantly affected. Mono unsaturated fatty acids (MUFA) was the main content of FAs, following by saturated FA and polyunsaturated FA. C 18:1n9c was the major FA, following by C 16:0 and C 18:0 . Six kinds of organic acids in dry-cured sausages containing different concentrations of sugar were analyzed by HPLC and the total organic acid reached a maximum of 12.15% by after adding 6% sugar. Acetic acid was 8.06% and lactic acid was 2.56%. This study concludes that sugar is the main factor in flavor formation of dry cured sausage and affects the sausage quality for three months in storage.

Extracellular Glycolytic Activities in Root Endophytic Serendipitaceae and Their Regulation by Plant Sugars.

Endophytic fungi that colonize the plant root live in an environment with relative high concentrations of different sugars. Analyses of genome sequences indicate that such endophytes can secrete carbohydrate-related enzymes to compete for these sugars with the surrounding plant cells. We hypothesized that typical plant sugars can be used as carbon source by root endophytes and that these sugars also serve as signals to induce the expression and secretion of glycolytic enzymes. The plant-growth-promoting endophytes Serendipita indica and Serendipita herbamans were selected to first determine which sugars promote their growth and biomass formation. Secondly, particular sugars were added to liquid cultures of the fungi to induce intracellular and extracellular enzymatic activities which were measured in mycelia and culture supernatants. The results showed that both fungi cannot feed on melibiose and lactose, but instead use glucose, fructose, sucrose, mannose, arabinose, galactose and xylose as carbohydrate sources. These sugars regulated the cytoplasmic activity of glycolytic enzymes and also their secretion. The levels of induction or repression depended on the type of sugars added to the cultures and differed between the two fungi. Since no conventional signal peptide could be detected in most of the genome sequences encoding the glycolytic enzymes, a non-conventional protein secretory pathway is assumed. The results of the study suggest that root endophytic fungi translocate glycolytic activities into the root, and this process is regulated by the availability of particular plant sugars.

Flight distance and foraging of Tetragonisca fiebrigi (Apidae: Meliponini) in response to different concentrations of sugar in food resources and abiotic factors

Social bees rely on food resources collected from flowers while foraging to guarantee the survival of their offspring. Pollen and nectar are the most important of these resources for protein and energy sources. This study analyzed the maximum flight distance of Tetragonisca fiebrigi (Shwarz, 1938) and the influence of sugar concentration of food resources and abiotic factors on visiting rates. Experiments were carried out in the Botanical Garden in South Brazil. The workers were training to collect sugar syrup from artificial feeders (water and sugar, 1:1) to which an aromatic essence (peach) had been added to attract the bees. It was found that workers reduced the number of visits as the distance to food sources increased. The experiments with feeders indicated that the maximum flight distance of T. fiebrigi workers from the four colonies analyzed reached 600 m. Additionally, 95% of visits to the feeder were within 350 m (colony C) or 400 m (colonies A, B, and D) of the hives. The number of worker visits could be significantly explained for all colonies (p < 0.05) by a relationship with flight distance, with explanatory power ranging from 65% to 89%. Regarding accumulated foraging activity, 75% was concentrated in distances up to 200 m from the colonies and the recruitment increased in higher sugar concentrations. Knowledge about achievable flight distances and effective foraging areas enables the planning of conservation measures, such as ensuring the availability of food resources in the landscape.

Does ‘Prison Napalm’ work? Measuring the cooling temperature of sugar solution burns in a porcine model

Non-accidental scalds sustained with sugar solution are potentially devastating and often associated with assaults within prisons where they are commonly known as ‘Napalm’ attacks. However, little is known about the mechanism behind such injuries. Proposed explanations have included a higher initial temperature, increased viscosity compared to water and lower emissivity, although these have yet to be demonstrated in any experimental model. We therefore set out to measure the post-exposure cooling temperature of the dermis after exposure to different concentrations of boiled sugar solution in a dead porcine model.Dead pork belly tissue was pre-heated to human body temperature (36.3–38.4 °C). Five solutions with different concentrations of sugar (0, 250, 500, 1000 and 2000 g/L) were heated to boiling point using standard commercially available kettles and then poured directly onto the tissue. Intradermal temperatures of the dermis were measured at one-minute intervals for a duration of 10 min.At one-minute after exposure, average intradermal porcine temperatures were 46.7 °C, 47.9 °C, 48.9 °C, 50.8 °C and 51.7 °C respectively for increasing concentrations of sugar solution. The rate of cooling was similar in all solutions with an average loss of 1.5 °C per minute. Using a generalised mixed model accounting for concentration and time period, it was identified that increasing sugar concentration resulted in statistically higher temperatures of burn (p = 0.006).Our report finds that higher concentrations of boiled sugar solution caused a higher initial temperature of burn but did not influence cooling rates. This suggests that ‘Prison Napalm’ attacks will indeed cause more severe burns than those utilising plain water, but not for all the widely believed reasons. We therefore recommend that access to kettles in prison cells should be limited, but where such access is deemed a right, consideration should be given to temperature restricted devices, as is the case in other countries.

Glucose detection of ringer-lactate solution using electrical bioimpedance: preliminary results

Continuous glucose monitoring is essential to reduce the damages caused by diabetes and for choosing the right treatment approach. In most cases, non-invasive glucose measurement devices generate their results through statistical tools (e.g., artificial neural networks) with an error that increases the further away from the training sample the measurement is. An analytical model would contain only propagated errors. Impedance measurements of lactate ringer’s solutions with egg albumin containing different concentrations of sugar were performed to validate the model proposed for measuring glycemia in human blood using the electrical bioimpedance meter AD5933. The curve fitting showed errors lower than 1.5%. Chemical phenomena, such as reduced sugar, fructosamine and solvation, might explain the behaviors observed in the experiments. The results suggest that the relaxation coefficient has significant changes with the increase of sugar in the solutions. The findings encourage future research with bovine blood for a more realistic analytical model.

Proboscis behavioral response of four honey bee Apis species towards different concentrations of sucrose, glucose, and fructose

Honey bees forage for pollen and nectar. Sugar is an important stimulus for foraging and a major source of energy for honey bees. Any differential response of bees to different concentrations of sugary nectar can affect their foraging. The sugar responsiveness of Apis species (Apis dorsata, Apis florea, and Apis cerana) was determined in comparison to that of Apis mellifera by evaluating the proboscis extension response (PER) with eight serial concentrations (0.00001, 0.0001, 0.001, 0.01, 0.1, 0.5, 1.0, and 1.5 M) of sucrose, glucose and fructose. Nectar foragers of bee species (A. dorsata, A. florea, A. cerana, and A. mellifera) exhibited an equal response for sucrose, glucose, and fructose, with no significant differences in their PER at all tested concentrations of these sugars within the same species. The inter-species comparison between Apis species revealed the differential responsiveness to the different concentrations of sugars, and the lowest concentration at which a response occurs was considered as the response threshold of these bee species for sugar solutions. A. mellifera presented significantly higher responsiveness than A. dorsata to low concentrations (0.00001, 0.0001, 0.001, 0.01, and 0.1 M) of sucrose, glucose and fructose. A. mellifera displayed a significantly higher response to water than A. dorsata. A. florea and A. mellifera presented no significant difference in their responsiveness to sucrose, glucose, and fructose at all tested concentrations, and their water responsiveness was also significantly at par but relatively higher in A. mellifera than in A. florea. Likewise, the responsiveness of A. cerana and A. mellifera to different concentrations of sucrose, glucose and fructose was significantly at par with no difference in their water responsiveness. This study represents preliminary research comparing the response of different honey bee species to three sugar types at different concentrations. The results imply that the native species are all better adapted than A. mellifera under local climate conditions.

In vitro: Influence of Various Concentrations of Plant Growth Regulators (BAP &amp; NAA) and Sucrose on Regeneration of Chenopodium quinoa Willd. Plant

In vitro: regeneration of Chenopodium quinoa Willd. was achieved from cotyledonary nodes explants. In this study, used 6-Benzylaminopurine (BAP) and α-Naphthalene Acetic Acid (NAA) of plant growth regulators with different concentrations individually as well as in combination and used different concentrations of sugar (sucrose) with different concentrations. For was rooting, used half strength (½MS), full-strength MS and ½ MS supplemented with 0.2 mg/l of NAA. The results mentioned, explant responding (%) to multiplication was about 73% for all BAP treatments compared with control and average numbers of shoot increased with increased BAP concentration except 5 mg/l of BAP. The highest explant responding (%) was in media supplemented BAP without NAA compared other treatments noted that the media with combination of BAP and NAA gives formation of callus in bases of the plantlets. Also, the result inducted the combinations between (BAP–NAA) was highly significantly (P≤ 0.001) and less effective on number of shoots where the highest number of shoot was 3.40 in media with 3 mg/l BAP compared other treatments. The highest of explant responding 93.33% was in media supplement with 10 g/l sucrose and (10 g/l sucrose + 3 mg/l BAP), but sucrose level for good greening and developed shoots (4 shoots) was in medium supplement with 10 g/l sucrose. The shoots rooted well on half-strength MS medium with 60% percentage of root. The rooted shoots were acclimatized and transferred to green house to follow their development.

Development and Optimization of Ready to Serve (RTS) Beetroot Drink

Beetroot is rich in various nutrients. Hence the present study was conducted to develop a ready to serve (RTS) drink using beetroot juice. The juice of beetroot was extracted and added with different concentrations of sugar and citric acid to optimize the best-suited combination of ingredients. Standardization of RTS was done using ranking sensory evaluation test. Two variants of ginger and black pepper flavor were also prepared and standardized. The standardized amount of ingredients after sensory analysis for RTS was found to be 17.7% juice content, 7.5% sugar and 0.1% citric acid. The black pepper variant was standardized at 0.4% black pepper in the original product and the ginger variant standardized at 1.5% ginger extract. The beetroot drink and its variants having an optimized amount of ingredients were analysed for their physico-chemical properties. Shelf life analysis for a period of one month was also carried out.

Study of The Effect of Sugar and Lime Juice Proportion on the Quality of Starf Ruit Sorbet

Star fruit is a non-seasonal fruit that can be harvested three to four times a year. One possible way to process a star fruit is to make it into sorbet. Additional ingredients such as sugar and lime juice will help improve the quality of star fruit sorbet. The purpose of this study was to acquire the best formulation of honey star fruit sorbet by adding sugar and lime juice and to find out the effect of different concentration of sugar and lime juice on the level of predilection, physical traits, level of vitamin C, and antioxidants activity. This study consisted of two phases; the production of lime essence in phase one and the making of star fruit sorbet in phase two as the main study. The result of best formulations selected based on organoleptic test of panellists’ level of predilection were formulation of 150 g sugar + 30 g lime, 90 g sugar + 60 g lime, and 120 g sugar + 60 g lime. Analysis of variance results indicated different formulation of star fruit sorbet had significant effect (P&lt;0.05) on colour, flavour, aroma, and overall but showed no difference on the texture of star fruit sorbet. Overall, the best formulation was 150 g sugar + 30 g lime juice with overrun score of 23.52%, pH 4.20, sugar content of 26.85 oBrix, melting time of 43.16 minutes, vitamin C content of 0.968 mg, and antioxidant activity of 320.86 ppm.Keyword: antioxidant activity; hedonic test; organoleptic test.

Effects of different types of sugars and plant growth regulators on kohlrabi seedling growth and development in vitro

Kohlrabi (Brassica oleracea var. gongylodes), with its edible stem tuber formed at the base of the plant stem, presents a valuable source of nutrients. The potential effects of plant growth regulators (PGRs), as well as various concentrations of different sugars on the in vitro development of kohlrabi were studied. Ten-day-old kohlrabi seedlings were cultivated in vitro for 5 weeks at 18?2?C on half-strength MS media containing different concentrations of carbon source such as sucrose, fructose, glucose, xylose and mannitol, combined with or without specific plant growth regulators (N6-benzyladenine (BA), gibberellic acid (GA3), 2,3,5-triiodobenzoic acid (TIBA)). Results showed no tuber formation in all treatments, but growth and development of treated kohlrabi seedlings was significantly affected in a distinctive manner, with a variety of morphological traits being altered in comparison to matching controls.

Harvest rates and foraging strategy of Carollia perspicillata (Chiroptera: Phyllostomidae) in an artificial food patch

An organism’s foraging strategy depends on its ability to acquire and use information from food patches. A forager that does not obtain information from a food patch should remain there for a fixed time or a fixed amount of harvest. Foragers that obtain partial or complete information from the patch should be able to estimate costs and benefits from its exploitation. The foraging strategy used by a forager can be determined using the giving-up density (GUD) technique. The GUD is the amount of food left by a forager after feeding in a patch with diminishing returns. We constructed an artificial feeder to examine the foraging strategy of the short-tailed fruit bat Carollia perspicillata (Chiroptera: Phyllostomidae). In this feeder, the bat’s harvest rate declined with time, i.e., they experienced diminishing returns. When offered feeders with different initial food densities, bats consumed proportionately more from rich patches than from poor ones, but they equalized GUDs. When offered feeders with different concentrations of sugar (i.e., different energy content), the higher the sugar concentration in the food, the more they consumed. Altogether, the evidence indicates that these fruit bats used complete, unbiased information to decide how much time to stay in a food patch.