1,720,965 research outputs found
Effects of Marinating Factors on the Quality of Beef Satay
Get PDFA series of experiments were undertaken to investigate the effects of satay marinade on
beef texture by measuring its physical changes in terms of weight gain, cooking loss and
WBSF values. Experiment I was designed to find the main substances in satay marinade
that alters the weight gain, cooking loss and WBSF values. Tenderloin beef muscle was
selected and assigned into five treatments; i.e., control, brine solution, tamarind juice,
tamarind juice plus salt and satay marinade for 30, 60, 90, 120, 150, and 180 minutes of
marinating time. Experiment II was conducted to investigate the influence of muscles type,
blade roast (BR), biceps femoris (BF) and semitendinosus (ST) on weight gain and cooking
loss, and the semitendinosus muscle was used for further assessment of tenderness. All the
beef muscles were assigned into treatments and marinating times as defined in experiment
I. Experiment III was designed to find the better marinating temperature between 4 °C (in
refrigerator) and 25 °C (room temperature) on weight gain for beef cuts in satay marinade Chuck tender beef cuts were assigned into two treatments of control and satay marinade in
two different marinating temperatures of 4 °C and 25 °C for 1st, 2nd, 3rd, 4th, 5th and 6th hour
of marinating times. The marinating time was extended to 7th, 9th, 12th and 24th hour for the
4°C in order to establish a relationship between weight gain and marinating time.
Experiment IV was conducted to find the correlation between weight gain, cooking loss
and WBSF values of tenderloin beef cuts marinated in satay marinade for 1, 2, 3, 4, 5, and
6 hours marinating time at 4°C.
Tenderloin beef cuts that were marinated in tamarind juice plus salt and satay marinade did
not show significant difference (P > 0.01) in weight gain, cooking loss and WBSF which
implied that tamarind juice plus salt were the main substances in satay marinade which
attributed to changes in measured physical parameters. Although the tamarind juice
provided the acidic condition to the marinades, it did not enhance meat water effectively
due to the inductive effect of tartaric acid. Linear regression analysis found that the
tenderness of tenderloin samples increases linearly (P < 0.05) with increasing weight gain,
but it decreases linearly (P < 0.05) with increasing cooking loss, irrespective of treatments.
The weight gain of both BF and ST were found significantly higher (P < 0.01) than BR,
but showed no significant difference (P > 0.01) between themselves in brine solution,
tamarind juice plus salt and satay marinade treatments, which implied that BF and ST
muscles from the same carcass have almost similar water binding ability. The beef chuck
cuts marinated in satay marinade at 4 °C is more flavourable in meat water enhancing compared to 25 °C (P < 0.01), but the influence of marinating temperature will only be
significance for at least two hours of marinating time. A best fitted equation was
established to express the relationship of weight gain of beef cuts marinated at 4 °C in
response to marinating time up to 24th hour. Prediction from the equation found that the
extended marinating time above six hours did not give any significant positive effect in
water enhancing for beef chuck muscles marinated in satay marinade at 4 °C, and the
weight gain rate was found at highest rate at the first two hours of marination, particularly
at the beginning of 10 minutes.
The strong negative correlation between weight gain and WBSF (P < 0.05), and positive
correlation between cooking loss and WBSF values (P < 0.01) found for tenderloin meat
marinated in satay marinade highlighted the importance of water enhancement and
cooking loss reduction in determining the tenderness of cooked tenderloin cuts. The local
tenderloin beef and chuck tender block were recommended in preparation of satay based
on data obtained. Marinating time of two hours at 4 °C is sufficient for beef cuts to
equilibrate with satay marinade in order to have maximum water enhance
Extraction of total phenolic and total monomeric anthocyanin contents from mangosteen (garcinia mangostana L.) hull
Get PDFMangosteen is a popular local tropical fruit because the pulp is delicious and has high value of nutrient and mineral content. However, mangosteen hull is disposed of as waste by local people due to the unpleasant taste of bitterness, though it contains total phenolic and anthocyanins which have numerous important pharmaceutical properties. Due to the remarkable relationship between total phenolic content (TPC) and total monomeric
anthocyanin (TMA) with antioxidant capacity, a series of investigations were undertaken to enhance the mangosteen crude extract yields evaluated in terms of TPC and TMA.
This research involved investigations from fundamental to optimization, based on hypotheses of methanol, acidic condition of extraction solvent, and the ultrasonic wave
treatment could give higher extraction yield. Results were expressed in mg gallic acid/g hull powder for TPC, while for TMA, expressed in mg cy-3-glu/g hull powder.
The effect of solvents, i.e. ethyl acetate, isopropanol, acetone, ethanol, methanol, and distilled water were evaluated on the extraction of total phenolic content (TPC) from mangosteen. Methanol was found as the most effective solvent in giving the highest recovery (p < 0.05) of TPC, compared to ethanol, acetone, isopropanol, ethyl acetate and distilled water. Regression equations of strong coefficients of determinations (R2 0.990) were obtained for UV-Vis spectrophotometer direct absorbance of acetone,
ethanol, and methanol extracts with the Folin-Ciocalteu (FC) method, suggesting regression equations obtained can be used to determine TPC without using the FC method.
The optimum conditions of extraction time, solid to solvent ratio, and methanol concentration for extraction of total phenolics from mangosteen hull powder was investigated using the response surface methodology (RSM). The experimental data obtained was adequately fitted into second-order polynomial models with R2 of 0.897.
Optimal extraction parameters which gave a maximum TPC yield of 140.66 mg (gallic acid equivalent) GAE/g powder were from a 2 hours‘ extraction with 0.05 solid to
solvent ratio and at 69.77% methanol concentration. Analysis using artificial neural network (ANN) predicted data which showed a higher R2 value of 0.945 and average
absolute deviation values of 4.01% versus 5.37% for the RSM. This suggests that ANN is a better modeling technique for nonlinear data for predicting TPC yield extracted from
mangosteen hull powder compared to the RSM.
The recovery of anthocyanins from mangosteen hull was investigated using aqueous methanol solvent acidified by juice from Mexican lime (C. aurantifolia Swingle) in
comparison with the conventional HCl acidified methanol solvent. The addition of 0.20 ml lime juice/ml methanol aqueous extraction solvent gave a maximum total monomeric anthocyanin (TMA) recovery of 4.742±0.590 mg cy-3-glu/g hull powder compared to 2.950±0.265 when using HCl acidified extraction solvent at 0.20%. A significant increase of 60.75% (p < 0.05) anthocyanins recovery suggests that this natural Mexican lime juice can be a good acidifying agent and replaces HCl. Particle size hull powder of 250 m to 500 m was also found to give the highest recovery of anthocyanins (p < 0.05).
Two types of extraction solvents, i.e., methanol and ethanol aqueous solvent acidified with 0.20% HCl were used to investigate the effect of ultrasonication time and
amplitude on TMA and TPC from mangosteen hull. The highest TMA recovery of 2.917±0.039 mg cy-3-glu/g hull powder was achieved using methanol 0.20% HCl acidified aqueous solvent with a pretreatment of an ultrasonic probe of 15 minutes‘
sonication time and 20% amplitude. While the highest recovery of TPC of 245.780±9.858 mg GAE/g hull powder was obtained using ethanol 0.20% HCl acidified aqueous solvent by pretreating the mangosteen sample with ultrasonic probe conditions of 25 minutes sonication time and 80% amplitude.
In conclusion, methanol has been found to be the best extraction solvent in giving the highest TPC yield. The optimum extraction conditions of 2 hours extraction time, 0.05 solid to solvent ratio and 69.77% methanol concentration obtained from RSM gave the maximum TPC yield 140.66 mg GAE/g hull powder with an improvement of 85.41%
compared to extraction with 20 hours extraction time, 0.20 solid to solvent ratio and pure methanol solvent. The extraction solvent acidified with 20 ml of Mexican lime
juice gave higher TMA yield compared to HCl acidified‘s. The ultrasonication of 15 inutes and 20% amplitude gave the highest TMA recovery of 2.917±0.039 mg cy-3-glu/g hull powder using acidified methanol solvent, while 25 minutes and 80% amplitude gave the highest TPC of 245.780±9.858 mg GAE/g hull powder using acidified ethanol solvent. Overall, the extraction of TPC and TMA yields from mangosteen hull have been optimized by reducing the extraction time, solid to solvent ratio using acidified extraction solvent with ultrasonic wave treatment
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Extraction and quantification of saponins: a review
Get PDFSaponins, a second metabolites mainly derived from plant materials, have been used extensively in drug-related industry due to the pharmaceutical properties. These have driven the emergence of various new extraction technologies with the main purpose to optimize the yield in order to accommodate the recent need. The plants containing saponins are discussed, and their pharmaceutical properties and applications in food are highlighted. This review focuses on the saponin extraction with emphasis on conventional and green technology techniques employed in previous works by relating to their specific objective in each study. The quantification methods of saponins yield, i.e., spectrophotometric and chromatographic, are summarized and discussed. In addition, this review aims to provide a point of reference to researchers who wish to design experiment to suit their particular objective in swift
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