Foods

18 pages, 1566 KiB

Open AccessArticle

Acceptability of Pulse-Fortified Foods by Two Groups: Participants in a Clinical Trial and Participants in a Consumer Acceptability Panel

by Donna Ryland, Peter Zahradka, Carla G. Taylor, Rhonda C. Bell and Michel Aliani

Foods 2018, 7(8), 129; https://doi.org/10.3390/foods7080129 - 18 Aug 2018

Cited by 8 | Viewed by 4169

Abstract

Pulses are nutrient-rich ingredients used as interventions in clinical trials to determine their effect on lowering blood lipids, which are risk factors for cardiovascular disease. Acceptability of these foods is critical for compliance by participants in clinical trials as well as regular consumption [...] Read more.

Pulses are nutrient-rich ingredients used as interventions in clinical trials to determine their effect on lowering blood lipids, which are risk factors for cardiovascular disease. Acceptability of these foods is critical for compliance by participants in clinical trials as well as regular consumption by those eating them for their health benefit. Commercialisation of foods that prove positive for health is required to make them available to the general population. Since the target for commercialisation would be products that will be procured by as many people as possible, the research question becomes whether or not testing is required by the clinical trial participants, by consumer acceptability testing in a sensory unit, or by both to ensure acceptability. The objective of this study was to determine the acceptability of pulse-based soups and casseroles destined for a clinical trial by both the participants in the clinical trial and by consumer participants not in the clinical trial. Neither group received any training regarding sensory analysis. Acceptability of aroma, appearance, flavor, texture, overall acceptability, and the frequency of eating the samples of five formulations fortified with either peas or beans was measured. Groups differed in their acceptability of foods for different attributes with the clinical trial participants providing less discrimination among the sensory attributes for their acceptability. Influential factors could include motivation for healthy eating, age, number of times the product was consumed, amount of the product consumed, and where it was consumed. In conclusion, acceptance measures from both groups are required in order to gain as much information as possible regarding acceptability of attributes for commercialisation of pulse-fortified foods that provide a health benefit. Full article

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14 pages, 4463 KiB

Open AccessArticle

Suppression of Pancreatin-Induced Digestion of Starch in Starch Granules by Starch/Fatty Acid and Starch/Flavonoid Complexes in Retrograding Rice Flour

by Sachiko Hirota and Umeo Takahama

Foods 2018, 7(8), 128; https://doi.org/10.3390/foods7080128 - 10 Aug 2018

Cited by 12 | Viewed by 4758

Abstract

Adzuki beans are used to prepare foods with glutinous and non-glutinous rice in Japan, and adzuki bean pigments are able to color rice starch a purplish red. This study deals with the adzuki bean extract-dependent suppression of starch digestion of non-glutinous rice flour [...] Read more.

Adzuki beans are used to prepare foods with glutinous and non-glutinous rice in Japan, and adzuki bean pigments are able to color rice starch a purplish red. This study deals with the adzuki bean extract-dependent suppression of starch digestion of non-glutinous rice flour (joshinko in Japanese), which was gelatinized in boiling water and then cooled to 37 °C. Accompanying the treatment of joshinko with pancreatin, amylose and amylopectin were released from the joshinko particles, and the released amylose and amylopectin were further digested. The adzuki extract suppressed the release and digestion by binding to amylose and amylopectin, which were present in the particles and at the surfaces of the particles. Fatty acids and flavonoids in the adzuki extract contributed to the suppression. In addition, the starch digestion in the joshinko particles appeared to be suppressed if the amylose/fatty acid complexes and amylose/flavonoid and amylopectin/flavonoid complexes, which are poor substrates of α-amylase, surrounded the particles. It is discussed that the suppression was due to the prevention of α-amylase access to the particles. Full article

(This article belongs to the Special Issue Starch: From a Complex Biopolymer to a Knowledge Driven Application in Food Systems)

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17 pages, 1621 KiB

Open AccessArticle

SPME Method Optimized by Box-Behnken Design for Impact Odorants in Reduced Alcohol Wines

by Bithika Saha, Rocco Longo, Peter Torley, Anthony Saliba and Leigh Schmidtke

Foods 2018, 7(8), 127; https://doi.org/10.3390/foods7080127 - 10 Aug 2018

Cited by 15 | Viewed by 6306

Abstract

The important sampling parameters of a headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) procedure such as the extraction temperature, extraction time, and sample volume were optimized to quantify 23 important impact odorants in reduced alcohol red and white wines. A three-factor design of Box-Behnken [...] Read more.

The important sampling parameters of a headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) procedure such as the extraction temperature, extraction time, and sample volume were optimized to quantify 23 important impact odorants in reduced alcohol red and white wines. A three-factor design of Box-Behnken experiments was used to determine the optimized sampling conditions for each analyte, and a global optimized condition at every ethanol concentration of interest determined using a desirability function that accounts for a low signal response for compounds. Shiraz and Chardonnay wines were dealcoholized from 13.7 and 12.2% v/v ethanol respectively, to 8 and 5% v/v, using a commercially available membrane-based technology. A sample set of the reduced alcohol wines were also reconstituted to their natural ethanol level to evaluate the effect of the ethanol content reduction on volatile composition. The three-factor Box-Behnken experiment ensured an accurate determination of the headspace concentration of each compound at each ethanol concentration, allowing comparisons between wines at varying ethanol levels to be made. Overall, the results showed that the main effect of extraction temperature was considered the most critical factor when studying the equilibrium of reduced alcohol wine impact odorants. The impact of ethanol reduction upon the concentration of volatile compounds clearly resulted in losses of impact odorants from the wines. The concentration of most analytes decreased with dealcoholization compared to that of the natural samples. Significant differences were also found between the reconstituted volatile composition and 5% v/v reduced alcohol wines, revealing that the dealcoholization effect is the result of a combination between the type of dealcoholization treatment and reduction in wine ethanol content. Full article

(This article belongs to the Special Issue Wine Composition and Quality Analysis)

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7 pages, 683 KiB

Open AccessArticle

Recipes for Determining Doneness in Poultry Do Not Provide Appropriate Information Based on US Government Guidelines

by Edgar Chambers IV, Sandria Godwin and Taylor Terry

Foods 2018, 7(8), 126; https://doi.org/10.3390/foods7080126 - 9 Aug 2018

Cited by 6 | Viewed by 4053

Abstract

Research has shown that consumers use unsafe food handling practices when preparing poultry, which can increase the risk of foodborne illness such as salmonellosis or campylobacteriosis. Recipes from cookbooks, magazines, and the internet commonly are used as sources for consumers to prepare food [...] Read more.

Research has shown that consumers use unsafe food handling practices when preparing poultry, which can increase the risk of foodborne illness such as salmonellosis or campylobacteriosis. Recipes from cookbooks, magazines, and the internet commonly are used as sources for consumers to prepare food in homes and the expectation is that food will be safe when prepared. According to the United States Department of Agriculture (USDA), using a thermometer properly is the only way to accurately check for doneness of poultry. The objective of this study was to assess poultry recipes, including recipes for whole birds and poultry parts, to determine if food safety information concerning thermometer use was included within the recipe. Poultry recipes (n = 474) were collected from 217 cookbooks, 28 magazines, 59 websites, and seven blogs. Approximately 33.5% of the recipes contained a specific temperature for doneness, with 73% of those cooked to ≥165 °F/74 °C, as recommended by USDA. Ninety-four percent of recipes used cooking time and about half of the recipes used visual measurements, such as color or juices running clear, to determine doneness. This study showed that most recipes do not contain appropriate information to assure safe cooking of poultry by consumers. Modifying recipes by adding food safety information, such as thermometer use and proper temperatures, could increase the use of proper food preparation behaviors by consumers. Full article

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14 pages, 829 KiB

Open AccessArticle

Effects of Proteolytic and Lipolytic Enzyme Supplementations on Lipolysis and Proteolysis Characteristics of White Cheeses

by Oya Berkay Karaca and Mehmet Güven

Foods 2018, 7(8), 125; https://doi.org/10.3390/foods7080125 - 8 Aug 2018

Cited by 19 | Viewed by 6268

Abstract

Effects of proteolytic (Neutrase, Bacillus subtilis-originate, 0.20 (P1) and 0.40 g 100 L⁻¹ (P2)) and lipolytic (Piccantase A, Mucor miehei-originated, 0.05 (L1) and 0.10 g 100 L⁻¹ (L2)) enzyme supplementations to cheese milk on lipolysis and proteolysis characteristics of [...] Read more.

Effects of proteolytic (Neutrase, Bacillus subtilis-originate, 0.20 (P1) and 0.40 g 100 L⁻¹ (P2)) and lipolytic (Piccantase A, Mucor miehei-originated, 0.05 (L1) and 0.10 g 100 L⁻¹ (L2)) enzyme supplementations to cheese milk on lipolysis and proteolysis characteristics of 90-day ripened cheese samples were investigated in this study. While enzyme supplementation did not have significant effects on titratable acidity, fat and protease-peptone nitrogen ratios of cheese samples, dry matter, salt, protein, water soluble nitrogen, 12% trichloroacetic acid soluble nitrogen ratio (TCA-SN), 5% phosphotungstic acid soluble nitrogen (PTA-SN), casein nitrogen ratios, penetrometer value, total free fatty acids (TFFA) and total free amino acids (TFAA) were significantly influenced by enzyme supplementations. Individual free amino acids (15 of them) were also determined. Free amino acid contents of enzyme-supplemented cheeses were higher than the control cheese and the values increased in all cheese samples with the progress of ripening (p < 0.05). The highest amino acids in all periods of ripening were identified as glutamic acid, lysine, proline and aspartic acid. The major (Ca, P, Na, K, Mg) and minor (Zn, Fe, Cu, Mn) mineral levels of cheeses decreased with the progress of ripening and the effects of enzyme supplementations on these attributes (except for magnesium and manganese) were found to be significant (p < 0.01). As to conclude, enzyme supplementations increased proteolysis and lipolysis and accelerated ripening and thus reduced ripening durations. Especially the enzyme ratios in P1 and L1 cheeses were found to be suitable for reducing the ripening period in White cheese without any adverse effects. Full article

(This article belongs to the Special Issue Selected Papers from International Conference on Raw Material to Processed Foods)

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9 pages, 253 KiB

Open AccessArticle

Nutritional Characterization of Prosopis laevigata Legume Tree (Mesquite) Seed Flour and the Effect of Extrusion Cooking on its Bioactive Components

by Luis Díaz-Batalla, Juan P. Hernández-Uribe, Roberto Gutiérrez-Dorado, Alejandro Téllez-Jurado, Javier Castro-Rosas, Rogelio Pérez-Cadena and Carlos A. Gómez-Aldapa

Foods 2018, 7(8), 124; https://doi.org/10.3390/foods7080124 - 1 Aug 2018

Cited by 24 | Viewed by 5998

Abstract

Mesquite (Prosopis laevigata) is a legume tree widely distributed in Aridoamerica. The mature fruit of this legume is a pod, which is currently underutilized and has high nutritional potential. In the present work, mesquite seed flour is described in terms of [...] Read more.

Mesquite (Prosopis laevigata) is a legume tree widely distributed in Aridoamerica. The mature fruit of this legume is a pod, which is currently underutilized and has high nutritional potential. In the present work, mesquite seed flour is described in terms of its nutritional value, as well as the effect of extrusion cooking on its bioactive components. Mesquite seed flour is rich in fiber (7.73 g/100 g) and protein (36.51 g/100 g), with valine as the only limiting amino acid. Total phenolic compound contents in raw and extruded seed flour were 6.68 and 6.46 mg of gallic acid equivalents/g (mg GAE/g), respectively. 2-2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity values in raw and extruded seed flour were 9.11 and 9.32 mg of ascorbic acid equivalent/g (mg AAE/g), respectively. The absorbance at 290 nm, as an indicator of generation of Maillard reaction product (MRP), was the same for raw and extruded samples. Apigenin was the only flavonoid found in mesquite seed flour (41.6 mg/kg) and was stable in the extrusion process. The water absorption index (WAI) and water solubility index (WSI) were changed significantly during extrusion. The expansion of mesquite seed flour extrudates was null due to the high protein and fiber content in the sample. Extrusion cooking of mesquite seed flour is a useful form of technology for the industrialization of this underutilized and nutritionally valuable legume. Full article

(This article belongs to the Special Issue Food Legumes: Physicochemical and Nutritional Properties)

12 pages, 1208 KiB

Open AccessArticle

Effect of Traditional Household Processes on Iron, Zinc and Copper Bioaccessibility in Black Bean (Phaseolus vulgaris L.)

by Sabrina Feitosa, Ralf Greiner, Ann-Katrin Meinhardt, Alexandra Müller, Deusdélia T. Almeida and Clemens Posten

Foods 2018, 7(8), 123; https://doi.org/10.3390/foods7080123 - 31 Jul 2018

Cited by 38 | Viewed by 7976

Abstract

Micronutrient deficiencies are a major public health problem. Beans are an important plant-based source of iron, zinc and copper, but their absorption is reduced in the presence of anti-nutrients such as phytates, polyphenols and tannins. Soaking and discarding the soaking water before cooking [...] Read more.

Micronutrient deficiencies are a major public health problem. Beans are an important plant-based source of iron, zinc and copper, but their absorption is reduced in the presence of anti-nutrients such as phytates, polyphenols and tannins. Soaking and discarding the soaking water before cooking is unanimously recommended, but this can result in mineral loss. Data on the consequences for mineral bioaccessibility is still limited. This study aimed to evaluate iron, zinc and copper bioaccessibility in black beans cooked (regular pan, pressure cooker) with and without the soaking water. For that, three batches of black beans were investigated in triplicate, each split in nine parts (raw grains and four different household processes in duplicate) and analyzed by applying the quarter technique, resulting in a grand total of 164 samples. Minerals were quantified by ICP-MS (inductively coupled plasma mass spectrometry), myo-inositol phosphates (InsP₅, InsP₆) by HPLC (high-performance liquid chromatography) ion-pair chromatography, total polyphenols using Folin-Denis reagent and condensed tannins using Vanillin assay. Mineral bioaccessibility was determined by in vitro digestion and dialysis. All treatments resulted in a statistically significant reduction of total polyphenols (30%) and condensed tannins (20%). Only when discarding the soaking water a loss of iron (6%) and copper (30%) was observed, and InsP₆ was slightly decreased (7%) in one treatment. The bioaccessibility of iron and zinc were low (about 0.2% iron and 35% zinc), but copper presented high bioaccessibility (about 70%). Cooking beans under pressure without discarding the soaking water resulted in the highest bioaccessibility levels among all household procedures. Discarding the soaking water before cooking did not improve the nutritional quality of the beans. Full article

(This article belongs to the Special Issue Food Legumes: Physicochemical and Nutritional Properties)

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13 pages, 13690 KiB

Open AccessArticle

Detection, Purity Analysis, and Quality Assurance of Adulterated Peanut (Arachis hypogaea) Oils

by Shayla C. Smithson, Boluwatife D. Fakayode, Siera Henderson, John Nguyen and Sayo O. Fakayode

Foods 2018, 7(8), 122; https://doi.org/10.3390/foods7080122 - 31 Jul 2018

Cited by 10 | Viewed by 6349

Abstract

The intake of adulterated and unhealthy oils and trans-fats in the human diet has had negative health repercussions, including cardiovascular disease, causing millions of deaths annually. Sadly, a significant percentage of all consumable products including edible oils are neither screened nor monitored for [...] Read more.

The intake of adulterated and unhealthy oils and trans-fats in the human diet has had negative health repercussions, including cardiovascular disease, causing millions of deaths annually. Sadly, a significant percentage of all consumable products including edible oils are neither screened nor monitored for quality control for various reasons. The prospective intake of adulterated oils and the associated health impacts on consumers is a significant public health safety concern, necessitating the need for quality assurance checks of edible oils. This study reports a simple, fast, sensitive, accurate, and low-cost chemometric approach to the purity analysis of highly refined peanut oils (HRPO) that were adulterated either with vegetable oil (VO), canola oil (CO), or almond oil (AO) for food quality assurance purposes. The Fourier transform infrared spectra of the pure oils and adulterated HRPO samples were measured and subjected to a partial-least-square (PLS) regression analysis. The obtained PLS regression figures-of-merit were incredible, with remarkable linearity (R² = 0.994191 or better). The results of the score plots of the PLS regressions illustrate pattern recognition of the adulterated HRPO samples. Importantly, the PLS regressions accurately determined percent compositions of adulterated HRPOs, with an overall root-mean-square-relative-percent-error of 5.53% and a limit-of-detection as low as 0.02% (wt/wt). The developed PLS regressions continued to predict the compositions of newly prepared adulterated HRPOs over a period of two months, with incredible accuracy without the need for re-calibration. The accuracy, sensitivity, and robustness of the protocol make it desirable and potentially adoptable by health departments and local enforcement agencies for fast screening and quality assurance of consumable products. Full article

(This article belongs to the Special Issue Food Legumes: Physicochemical and Nutritional Properties)

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16 pages, 10778 KiB

Open AccessArticle

Optimization of Cactus Pear Fruit Fermentation Process for Wine Production

by Zenebe Tadesse Tsegay, Chanukya Basavanahally Sathyanarayana and Solomon Mengistu Lemma

Foods 2018, 7(8), 121; https://doi.org/10.3390/foods7080121 - 30 Jul 2018

Cited by 23 | Viewed by 7181

Abstract

Cactus pear fruit (Opuntia ficus-indica) has a chemical composition that renders it an attractive substrate for wine fermentation. However, there have been serious post-harvest losses of cactus fruit due to its short shelf life. This study aims to investigate wine production [...] Read more.

Cactus pear fruit (Opuntia ficus-indica) has a chemical composition that renders it an attractive substrate for wine fermentation. However, there have been serious post-harvest losses of cactus fruit due to its short shelf life. This study aims to investigate wine production from cactus pear fruit juice by optimizing fermentation temperature, pH, and inoculum concentration (Saccharomyces cerevisiae) to obtain optimum quality-indicative responses. Response surface methodology coupled with central composite rotatable design was adopted in the present study to achieve optimized fermentation process conditions. The fermentation process was carried out for 6 days with varied input variables, and all the models showed significant p-values for interaction of variance (<0.05). Cactus pear fruit wine with a total acidity of 12.39 ± 1.32 g/L equivalent to tartaric acid (TTAE), alcohol content of 9 ± 0.31%, v/v, total antioxidant concentration of 235.3 ± 9.15 mg/L AAE (Ascorbic acid equivalent), and sensory acceptance of 7.74 ± 0.34 was produced at an optimized temperature of 30 °C, pH of 3.9, and inoculum concentration of 16%. The developed models could predict the quality of wine developed from cactus pear fruit. Full article

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13 pages, 1080 KiB

Open AccessArticle

Using Sensory Evaluation to Determine the Highest Acceptable Concentration of Mango Seed Extract as Antibacterial and Antioxidant Agent in Fresh-Cut Mango

by Ariadna Thalia Bernal-Mercado, Jesus Fernando Ayala-Zavala, Manuel Reynaldo Cruz-Valenzuela, Gustavo A. Gonzalez-Aguilar, Filomena Nazzaro, Florinda Fratianni, Maria Raquel Alcantara de Miranda and Brenda A. Silva-Espinoza

Foods 2018, 7(8), 120; https://doi.org/10.3390/foods7080120 - 30 Jul 2018

Cited by 12 | Viewed by 6377

Abstract

Plant extracts have the potential to be used as food additives; however, their use have been limited by causing undesirable changes in the sensory attributes of foods. We characterized the mango seed extract as a preserving agent for fresh-cut mangoes. We established the [...] Read more.

Plant extracts have the potential to be used as food additives; however, their use have been limited by causing undesirable changes in the sensory attributes of foods. We characterized the mango seed extract as a preserving agent for fresh-cut mangoes. We established the maximum concentration of extract that, while increasing the antioxidant activity, and limiting microbial contamination of the fruit, did not negatively affect fruit sensory acceptability. The extract contained 277.4 g gallic acid equivalent (GAE)/kg dw (dry weight) of polyphenols and 143.7 g quercetin equivalent (QE)/kg dw of flavonoids. Antioxidant capacity values were 2034.1 and 4205.7 μmol Trolox equivalent (TE)/g against 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals, respectively. Chromatographic analysis revealed the presence of gallic and chlorogenic acids. The extract (16 g/L) inhibited the growth of Escherichia coli, Salmonella Typhimurium, Staphylococcus aureus and Listeria monocytogenes. The highest concentration with sensory acceptability was 6.25 g/L. At such concentration, the extract preserved fresh-cut fruits, increasing polyphenols (0.427 g GAE/kg fw (fresh weight)), flavonoid content (0.234 g QE/kg fw) and antioxidant activity (DPPH = 2.814 and ABTS = 0.551 mol TE/kg fw). It also reduced inoculated bacteria (range: 5.50 × 10³ to 1.44 × 10⁵ colony forming units (CFU)/g). These results showed the importance of considering consumer acceptability to determine the effective concentration of plant extracts as additives. Full article

(This article belongs to the Special Issue Polyphenols and Foods: Authentication, Analysis and Characterization. Antioxidant and Antimicrobial Activity)

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14 pages, 1269 KiB

Open AccessArticle

See, Feel, Taste: The Influence of Receptacle Colour and Weight on the Evaluation of Flavoured Carbonated Beverages

by Line Ahm Mielby, Qian Janice Wang, Sidsel Jensen, Anne Sjoerup Bertelsen, Ulla Kidmose, Charles Spence and Derek Victor Byrne

Foods 2018, 7(8), 119; https://doi.org/10.3390/foods7080119 - 26 Jul 2018

Cited by 31 | Viewed by 9539

Abstract

A study was designed to assess whether the individual and combined effects of product-intrinsic and product-extrinsic factors influence the perception of, and liking for, carbonated beverages. Four hundred and one participants tasted samples of one of three flavours (grapefruit, lemon, or raspberry) of [...] Read more.

A study was designed to assess whether the individual and combined effects of product-intrinsic and product-extrinsic factors influence the perception of, and liking for, carbonated beverages. Four hundred and one participants tasted samples of one of three flavours (grapefruit, lemon, or raspberry) of carbonated aromatised non-alcoholic beer. The beverages were served in receptacles that differed in terms of their colour (red or black) and weight (lighter—no added weight, or heavier—20 g weight added). Each participant received the same beverage in each of the four different receptacles, and rated how much they liked the drink. They also evaluated the intensity of each beverage’s sweetness, bitterness, sourness, and carbonation. The results revealed a significant influence of the colour of the receptacle on perceived carbonation, with the beverages tasted from the red receptacles being rated as tasting more carbonated than when served in black receptacles. In terms of flavour, the participants liked the raspberry beverage significantly more than the others, while also rating it as tasting sweeter and less bitter than either of the other flavours. Furthermore, there was a more complex interaction effect involving the weight of the receptacle: Specifically, the perceived bitterness of the beverage moderated the relationship between the receptacle weight and the perceived carbonation. At high levels of bitterness, the drinks were perceived to be more carbonated when served from the heavier receptacle as compared to the lighter one. These findings highlight the complex interplay of product extrinsic and intrinsic factors on the flavour/mouthfeel perception and preference for beverages, and stress the importance of taking both internal product development and external packaging into account in the design of health-oriented beverages. Full article

(This article belongs to the Special Issue Sensory Nudges: The Influences of Environmental Contexts on Consumers’ Sensory Perception, Emotional Responses, and Behaviors toward Food and Beverages)

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3 pages, 176 KiB

Open AccessEditorial

Quality and Safety of Meat Products

by Begoña Panea and Guillermo Ripoll

Foods 2018, 7(8), 118; https://doi.org/10.3390/foods7080118 - 26 Jul 2018

Cited by 6 | Viewed by 4143

Abstract

n/a Full article

7 pages, 1230 KiB

Open AccessCommunication

Ethanol Measurement Using Hetero-Core Structured Optical Fiber Covered with Layer-By-Layer Thin Film

by Yuko Kimura, Atsushi Seki and Kazuhiro Watanabe

Foods 2018, 7(8), 117; https://doi.org/10.3390/foods7080117 - 25 Jul 2018

Cited by 1 | Viewed by 3993

Abstract

Ethanol measurements are performed in an ethanol/water solution utilizing an ethanol sensor based on a hetero-core structured optical fiber covered with a layer-by-layer thin film. The layer-by-layer (LbL) thin film was prepared using poly (allylamine hydrochloride) and poly styrene sulfonate. When the sensor [...] Read more.

Ethanol measurements are performed in an ethanol/water solution utilizing an ethanol sensor based on a hetero-core structured optical fiber covered with a layer-by-layer thin film. The layer-by-layer (LbL) thin film was prepared using poly (allylamine hydrochloride) and poly styrene sulfonate. When the sensor was immersed in water, the propagating light intensity decreased with increasing ethanol concentration. This behavior suggested that the LbL film contracted due to the presence of ethanol, and the refractive index of the film increased, resulting in increasing propagating light leaks at the hetero-core of the fiber. The ethanol sensor was applied to a variety of spirits, and the propagating light intensity decreased with increasing ethanol concentration. Full article

(This article belongs to the Special Issue Sensors Application in Food Analysis and Detection)

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Foods, Volume 7, Issue 8 (August 2018) – 13 articles

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