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1.
Food Res Int ; 194: 114905, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39232531

RESUMEN

The COVID-19 pandemic caused notable changes to the food-related habits of consumers worldwide due to their concerns about the risk of infection and the requirement to follow government mandates. To investigate the impact of the pandemic on Chinese consumers' food safety knowledge, food safety behaviors, and their most recent food poisoning experiences, we compared the results from an online survey (n = 583, Dec 2019) conducted before the pandemic was officially announced with an identical survey (n = 599, Aug 2023) conducted seven months after the Chinese government downgraded restrictions related to COVID-19. Post-pandemic there was a significant decrease in consumers' food safety knowledge and self-reported food safety behaviors and a significant increase in their self-reported experiences of food poisoning. Despite respondents stating that their food safety knowledge and behaviors had improved since the start of the pandemic, the data obtained from the two surveys and the respondents self-reporting of foodborne illness suggest that in fact their safety knowledge and behaviors had decreased. These findings highlight the need to reinforce food safety education and behaviors during times when the food system is disrupted, and consumers are focusing on what they perceive to be more immediate issues.


Asunto(s)
COVID-19 , Inocuidad de los Alimentos , Enfermedades Transmitidas por los Alimentos , Conocimientos, Actitudes y Práctica en Salud , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , China/epidemiología , Femenino , Masculino , Adulto , Enfermedades Transmitidas por los Alimentos/epidemiología , Enfermedades Transmitidas por los Alimentos/prevención & control , Persona de Mediana Edad , Adulto Joven , Encuestas y Cuestionarios , SARS-CoV-2 , Comportamiento del Consumidor , Población Urbana , Adolescente , Anciano , Pandemias
2.
Molecules ; 29(14)2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-39064855

RESUMEN

Bacterial fermentation is considered to be a cost-effective means of generating desired flavour compounds from plant-based substrates. However, the wide range of substrates present in plants makes it challenging to understand how individual components impact on flavour volatile organic compound (VOC) production. To simplify this, a defined medium can be used to better understand VOCs production with regard to individual compounds. In the current study, the VOCs produced by the lactic acid bacterium, Levilactobacillus brevis WLP672, growing in a defined medium containing different carbon sources (either glucose (DM), fructose (DMFr) or citrate (DMCi)) under a range of fermentation conditions (time: 0, 7, and 14 days; and temperature: 25 and 35 °C) were assessed using proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS). Among the detected mass peaks (m/z), after 7 days of fermentation, the concentrations of m/z 45.033 (t.i. acetaldehyde), m/z 49.011 (t.i. methanethiol), and m/z 89.060 (t.i. ethyl acetate) were significantly (p < 0.05) higher in DM at 35 °C than all other treatments at either temperature. The knowledge obtained will help to produce desirable LAB fermentation flavour VOCs or VOC mixtures that could be used in developing plant-based analogues with acceptable sensory properties.


Asunto(s)
Carbono , Fermentación , Levilactobacillus brevis , Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/metabolismo , Levilactobacillus brevis/metabolismo , Carbono/metabolismo , Espectrometría de Masas/métodos , Glucosa/metabolismo , Aromatizantes/metabolismo , Aromatizantes/análisis , Aromatizantes/química
3.
Molecules ; 29(4)2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38398505

RESUMEN

Fermentation by lactic acid bacteria (LAB) is a promising approach to meet the increasing demand for meat or dairy plant-based analogues with realistic flavours. However, a detailed understanding of the impact of the substrate, fermentation conditions, and bacterial strains on the volatile organic compounds (VOCs) produced during fermentation is lacking. As a first step, the current study used a defined medium (DM) supplemented with the amino acids L-leucine (Leu), L-isoleucine (Ile), L-phenylalanine (Phe), L-threonine (Thr), L-methionine (Met), or L-glutamic acid (Glu) separately or combined to determine their impact on the VOCs produced by Levilactobacillus brevis WLP672 (LB672). VOCs were measured using headspace solid-phase microextraction (HS-SPME) gas chromatography-mass spectrometry (GC-MS). VOCs associated with the specific amino acids added included: benzaldehyde, phenylethyl alcohol, and benzyl alcohol with added Phe; methanethiol, methional, and dimethyl disulphide with added Met; 3-methyl butanol with added Leu; and 2-methyl butanol with added Ile. This research demonstrated that fermentation by LB672 of a DM supplemented with different amino acids separately or combined resulted in the formation of a range of dairy- and meat-related VOCs and provides information on how plant-based fermentations could be manipulated to generate desirable flavours.


Asunto(s)
Butanoles , Levilactobacillus brevis , Pentanoles , Compuestos Orgánicos Volátiles , Aminoácidos , Fermentación , Compuestos Orgánicos Volátiles/análisis , Ácido Glutámico , Leucina , Isoleucina , Fenilalanina , Microextracción en Fase Sólida/métodos
4.
Foods ; 12(22)2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-38002108

RESUMEN

The impact of the ethylene inhibitor, 1-methylcyclopropene (1-MCP), on four apple cultivars (Braeburn, Fuji, Jazz and Golden Delicious) over 150 days of storage at 2 °C was assessed. Proton transfer reaction quadrupole mass spectrometry (PTR-QUAD-MS) was used to monitor changes in VOC composition, while texture analysis and X-ray microcomputer tomography (µ-CT) scanning were used to study microstructural changes. The application of 1-MCP on apples reduced VOC emissions, concurrently maintaining a firmer texture compared to the untreated apples at each time point. The µ-CT scanning revealed how changes in specific morphological characteristics such as anisotropy, connectivity and porosity, size and shape, as well as the interconnectivity of intracellular spaces (IS) influenced texture even when porosity was similar. Additionally, this study showed that the porosity and connectivity of IS were associated with VOC emission and increased simultaneously. This study highlights how the morphological parameters of an apple can help explain their ripening process during long-term storage and how their microstructure can influence the release of VOCs.

5.
Foods ; 12(16)2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37627981

RESUMEN

A challenge in social marketing studies is the cognitive biases in consumers' conscious and self-reported responses. To help address this concern, biometric techniques have been developed to obtain data from consumers' implicit and non-verbal responses. A systematic literature review was conducted to explore biometric applications' role in agri-food marketing to provide an integrated overview of this topic. A total of 55 original research articles and four review articles were identified, classified, and reviewed. It was found that there is a steady growth in the number of studies applying biometric approaches, with eye-tracking being the dominant method used to investigate consumers' perceptions in the last decade. Most of the studies reviewed were conducted in Europe or the USA. Other biometric techniques used included facial expressions, heart rate, body temperature, and skin conductance. A wide range of scenarios concerning consumers' purchase and consumption behaviour for agri-food products have been investigated using biometric-based techniques, indicating their broad applicability. Our findings suggest that biometric techniques are expanding for researchers in agri-food marketing, benefiting both academia and industry.

6.
J Mass Spectrom ; 58(10): e4959, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37491759

RESUMEN

Higher alcohols and esters are among the predominant classes of volatile organic compounds (VOCs) that influence the quality of beer. The concentrations of these compounds are determined through a specific yeast strain selection and fermentation conditions. The effect of yeast strains on the formation of higher alcohols and esters throughout fermentations (at 20°C) was investigated. Flavour-relevant esters (ethyl acetate, isoamyl acetate, ethyl hexanoate and ethyl octanoate) and higher alcohols (isoamyl alcohol, isobutyl alcohol and phenylethyl alcohol) were monitored throughout the fermentation using proton transfer reaction-time of flight-mass spectrometry (PTR-ToF-MS) coupled with an automated sampling system for continuous measurements. Compound identification was confirmed by analysis of samples using gas chromatography-mass spectrometry (GC-MS). Results demonstrated the specific time points where variation in higher alcohol and ester generation between yeast strains occurred. In particular, the concentrations of isoamyl acetate, ethyl octanoate and isoamyl alcohol between yeast strains were significantly different over the first 2 days of fermentation; whereas, after Day 3, no significant differences were observed. The two Saccharomyces pastorianus strains produced comparable concentrations of the key higher alcohols and esters. However, the key higher alcohol and ester concentrations varied greatly between the two S. cerevisiae strains. The use of PTR-ToF-MS to rapidly measure multiple yeast strains provides new insights on fermentation for brewers to modify the sensory profile and optimise quality.


Asunto(s)
Saccharomyces cerevisiae , Vino , Fermentación , Ésteres/análisis , Cerveza/análisis , Etanol , Vino/análisis
7.
J Food Sci ; 88(8): 3551-3561, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37458297

RESUMEN

An increasing number of novel food technologies have been developed to meet consumers' growing desire for safe and high-quality foods. However, consumers can be cautious of novel food technologies, and their acceptance cannot be guaranteed. Food Technology Neophobia Scales (FTNS) have been proven to be an effective tool to predict consumers' behavior toward novel food technologies in a range of individual countries, but not for cross-national contexts. To fill the gap, this study designed a survey involving 604 Chinese and 614 New Zealand respondents, investigating the influence of consumers' food technology neophobia (FTN) on their acceptance of food technologies. Chinese respondents' FTNS score (50.62) was lower than that of New Zealand respondents (55.02), which was in line with the finding that Chinese respondents' acceptance of all tested food technologies was higher than New Zealand respondents (0.34-0.86 in a Likert-7 scale). Chinese respondents' acceptance was determined by their perception of benefits, whereas New Zealand respondents were influenced by their perception of both benefits and risks. The findings conclude that FTNS is a valid tool to reflect consumers' acceptance of novel food technologies in cross-national contexts, although the influence of FTN varies among consumers from different countries. PRACTICAL APPLICATION: China has the largest food market, and New Zealand is a leading food exporter. Understanding their consumers' acceptance of and attitudes toward food technologies will help food companies implement appropriate strategies in developing and using novel technologies. Because FTNS first was constructed in 2008, it has been applied in Australia, Italy, Canada, Finland, Korea, China, Chile, Brazil, and Uganda; the findings of this study will allow these individual studies on FTNS to better connect, help food companies predict consumer acceptance of food technologies in the global market, and help them identify early adopters of novel food technologies in new food markets.


Asunto(s)
Actitud , Comportamiento del Consumidor , Tecnología de Alimentos , Humanos , Pueblos del Este de Asia , Nueva Zelanda , Encuestas y Cuestionarios
8.
Molecules ; 28(7)2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37049998

RESUMEN

Health, environmental and ethical concerns have resulted in a dramatic increase in demand for plant-based dairy analogues. While the volatile organic compounds (VOCs) responsible for the characteristic flavours of dairy-based products have been extensively studied, little is known about how to reproduce such flavours using only plant-based substrates. As a first step in their development, this review provides an overview of the VOCs associated with fermented (bacteria and/or fungi/yeast) vegetable and fruit substrates. Following PRISMA guidelines and using two English databases (Web of Science and Scopus), thirty-five suitable research papers were identified. The number of fermentation-derived VOCs detected ranged from 32 to 118 (across 30 papers), while 5 papers detected fewer (10 to 25). Bacteria, including lactic acid bacteria (LAB), fungi, and yeast were the micro-organisms used, with LAB being the most commonly reported. Ten studies used a single species, 21 studies used a single type (bacteria, fungi or yeast) of micro-organisms and four studies used mixed fermentation. The nature of the fermentation-derived VOCs detected (alcohols, aldehydes, esters, ketones, acids, terpenes and norisoprenoids, phenols, furans, sulphur compounds, alkenes, alkanes, and benzene derivatives) was dependent on the composition of the vegetable/fruit matrix, the micro-organisms involved, and the fermentation conditions.


Asunto(s)
Lactobacillales , Compuestos Orgánicos Volátiles , Verduras , Frutas/química , Saccharomyces cerevisiae , Terpenos/análisis , Alcoholes/análisis , Bacterias , Fermentación , Compuestos Orgánicos Volátiles/análisis
9.
Foods ; 12(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36900579

RESUMEN

The perception of hop-derived flavour in beer is not well understood, particularly regarding the effect that different yeast strains and fermentation parameters have on perceived hop aroma and the mechanisms responsible for these changes. To evaluate the influence of yeast strain on the sensory properties and volatile composition of beer, a standard wort, late-hopped with New Zealand Motueka hops (5 g·L-1), was fermented with one of twelve yeast strains under constant conditions (temperature and yeast inoculation rate). The bottled beers were evaluated using a free sorting sensory methodology, and their volatile organic compounds (VOC) were assessed using gas chromatography mass spectrometry (GC/MS) with headspace solid-phase microextraction (SPME) sampling. Beer fermented with SafLager W-34/70 yeast was associated with a hoppy flavour attribute, whereas WY1272 and OTA79 beers were sulfury, and WY1272 was also metallic. WB06 and WLP730 beers were perceived to be spicy, with WB06 beer also perceived as estery, whereas VIN13 beer was sour, and the WLP001 beer was astringent. Beers fermented using the twelve yeast strains had clearly distinct VOC profiles. Beer made with WLP730, OTA29, SPH, and WB06 yeasts had the highest 4-vinylguaiacol levels, which contributed to their spicy attribute. Beer made with W3470 had high levels of nerol, geraniol, and citronellol, which supported its sensory characterisation as being 'hoppy'. This research has illustrated the important role that yeast strain has on modulating hop flavour in beer.

10.
Food Res Int ; 163: 112251, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36596162

RESUMEN

The aim of this research was to investigate how the electrical conductivity of short ribs affected Pulsed Electric Field (PEF) process parameters and the ability of PEF to enhance their quality and reduce sous vide (SV) processing time. Short ribs with different range of electrical conductivity (3-6, 6-9, and 9-12 mS/cm) values were treated using input voltage of 10 kV, pulse width of 20 µs, pulse frequency of 50 Hz and pulse number, of either 1600 (low intensity PEF/LPEF) or 5200 (high intensity PEF/HPEF), followed by SV processing at 60 °C for either 24 or 36 h. The quality parameters assessed were cooking loss (%), Texture Profile Analysis (TPA) parameters, and Commission Internationale d'Eclairage (CIE) L*a*b* colour parameters. There was a variation in electrical conductivity of short ribs according to the position of the bone in the short rib, which demonstrated good congruence with the distribution of fat and connective tissue. SV processing with or without PEF pre-treatment did not have a significant effect (p > 0.05) on cooking loss or CIE L*a*b* colour parameters. Short ribs with a medium conductivity (6-9 mS/cm) had a significantly lower hardness after high intensity PEF followed by SV for 24 h, whilst short ribs with an average conductivity of 3-6 and 9-12 mS/cm required longer SV time (up to 36 h) and had a significantly lower hardness compared to non PEF pre-treated samples. TPA values of short ribs treated with the same PEF intensity and SV processing parameters were comparable regardless of the short ribs initial electrical conductivity, which indicates that PEF treatment could ameliorate the biological electrochemical variability inherent to short ribs and PEF could be the potential tool to decrease their SV processing time and enhance their tenderness.


Asunto(s)
Culinaria , Carne , Animales , Bovinos , Carne/análisis , Electricidad , Conductividad Eléctrica , Costillas
11.
Front Nutr ; 9: 1071829, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36479294

RESUMEN

One of the aims of the United Nations Sustainable Development Goals (SDG) is to end hunger and ensure access by all people to safe, nutritious, and sufficient food all year round. An obvious synergy exists between the second SDG "Zero Hunger" and SDG target 12.3 which focuses on halving food waste and reducing food losses. In addition to helping improve global food security, reducing food waste provides financial and environmental benefits. Upcycling food is a technical solution for food waste reduction that retains the nutritional and financial value of food by-products. However, many of the upcycled foods produced are discretionary foods such as biscuits, crackers, and other snack food that are not part of a healthy dietary pattern, and should only be eaten sometimes in small amounts. Given the importance of ensuring a sustainable healthy diet, this paper discusses opportunities for upcycled food manufacturers to produce more nutritious products.

12.
Foods ; 11(24)2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36553859

RESUMEN

The thermal processing of food relies heavily on determining the right time and temperature regime required to inactivate bacterial contaminants to an acceptable limit. To design a thermal processing regime with an accurate time and temperature combination, the D-values of targeted microorganisms are either referred to or estimated. The D-value is the time required at a given temperature to reduce the bacterial population by 90%. The D-value can vary depending on various factors such as the food matrix, the bacterial strain, and the conditions it has previously been exposed to; the intrinsic properties of the food (moisture, water activity, fat content, and pH); the method used to expose the microorganism to the thermal treatment either at the laboratory or commercial scale; the approach used to estimate the number of survivors; and the statistical model used for the analysis of the data. This review focused on Bacillus cereus, Cronobacter sakazakii, Escherichia coli, Listeria monocytogenes, and Clostridium perfringens owing to their pathogenicity and the availability of publications on their thermal resistance. The literature indicates a significant variation in D-values reported for the same strain, and it is concluded that when designing thermal processing regimes, the impact of multiple factors on the D-values of a specific microorganism needs to be considered. Further, owing to the complexity of the interactions involved, the effectiveness of regimes derived laboratory data must be confirmed within industrial food processing settings.

13.
Compr Rev Food Sci Food Saf ; 21(5): 4130-4145, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35791070

RESUMEN

Almost all processed food comes packaged in either plastic, glass, metal, or paper and paperboard materials, and many packaging materials are disposed of after a single use (linear economy). Based on the concept of a circular economy, the recycling of food packaging materials has become one of the main targets for industries and regulators around the world. However, recycling presents particular challenges, mainly related to the recycled material composition, which determines its reusability, application, functionality, and chemical safety. In this latter matter, it has been demonstrated that the use of recycled food packaging materials increases the number and possible sources of substances that could be present in the packaging material, which is of concern as substances that can migrate into food and cause health hazards upon consumption. This review compiles information regarding substances detected in non-permanent food packaging materials, focusing mainly on plastics, paper, and paperboards. The compilation of literature studies (110 research articles) on the presence of intentionally added substances (IAS) and non-intentionally added substances (NIAS) in food packaging materials, their migration, toxicity, and dietary exposure has been summarized, evaluated, and discussed. In addition, current sustainable food packaging trends have been mentioned. Finally, approaches to reduce the presence, migration, and potential exposure to substances that have migrated from packaging materials into food have been reviewed.


Asunto(s)
Contaminación de Alimentos , Embalaje de Alimentos , Contaminación de Alimentos/análisis , Plásticos/análisis , Reciclaje
14.
J Food Prot ; 85(7): 1017-1026, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35503972

RESUMEN

ABSTRACT: Chinese consumers (n = 604) were asked three times to rate their acceptance of traditional thermal processing and several newer technologies (high pressure processing, irradiation, bacteriophages, antimicrobial packaging, pulsed electric fields, and rinsing meat carcasses with antimicrobial solutions) designed to control foodborne bacteria in food (i) based on their existing knowledge, (ii) after the provision of information about L. monocytogenes, and (iii) after further reading a brief description of the technology. Thermal processing (6.00 of 7 on Likert scale) and high pressure processing (5.73 of 7) were rated the most acceptable technologies, and rinsing with antimicrobial solutions (4.43 of 7) was rated the least acceptable technology. Information outlining the benefits of a technology had a larger positive effect on acceptance of every novel technology discussed (increases of 0.14 to 0.49 units depending on the technology) than information about L. monocytogenes and a brief description of the technology. This research has shown that providing information about foodborne bacteria and a technology designed to control them will improve consumers' acceptance of the technology, with the provision of information being of most importance for technologies for which the consumers are less familiar. Chinese consumers accepted or rejected a food technology for a variety of reasons; however, consumers with a greater awareness of foodborne bacteria rated the acceptability of novel technologies designed to kill bacteria higher than those with a low awareness (0.56 to 1.71 units depending on the technology). The results of this research will be of benefit to food companies considering adopting novel technologies to control foodborne bacteria because they provide insights that will enable them to develop more effective communication and implementation strategies.


Asunto(s)
Tecnología de Alimentos , Carne , Bacterias , China , Carne/microbiología , Tecnología
15.
J Environ Manage ; 303: 114092, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34836675

RESUMEN

Although food loss and waste (FL&W) is high on China's national policy agenda, there is still little scientific information published about how much FL&W exists in China, what its impacts are, and what needs to be done to reduce it. Furthermore, what is known about FL&W across the various hotspots of China's food supply chain is not accessible in one place due to the tendency of scholars to focus on one part of the food chain depending on their disciplinary backgrounds, thereby making it difficult to obtain a 'comprehensive whole supply chain perspective'. Thus, this review provides an interdisciplinary collation of what is already known about FL&W in China. A systematic review of both English and Chinese databases followed PRISMA guidelines further complemented with a qualitative content analysis process uncovered 57 articles. The view revealed confounding factors such as an inconsistency of the definitions and calculation methods used to measure FL&W, and research gaps such as a lack of focus on the behavioral factors pertaining to waste, and the limited range of social innovations studied to reduce it. Thus, this review will help in the development of research agendas designed to advance efforts in this field.


Asunto(s)
Abastecimiento de Alimentos , Alimentos , China , Bases de Datos Factuales , Políticas
16.
Molecules ; 26(23)2021 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-34885824

RESUMEN

This study investigated the impact of varying sound conditions (frequency and intensity) on yeast growth, fermentation performance and production of volatile organic compounds (VOCs) in beer. Fermentations were carried out in plastic bags suspended in large water-filled containers fitted with underwater speakers. Ferments were subjected to either 200-800 or 800-2000 Hz at 124 and 140 dB @ 20 µPa. Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was used to identify and measure the relative abundance of the VOCs produced. Sound treatment had significant effects on the number of viable yeast cells in suspension at 10 and 24 h (p < 0.05), with control (silence) samples having the highest cell numbers. For wort gravity, there were significant differences between treatments at 24 and 48 h, with the silence control showing the lowest density before all ferments converged to the same final gravity at 140 h. A total of 33 VOCs were identified in the beer samples, including twelve esters, nine alcohols, three acids, three aldehydes, and six hop-derived compounds. Only the abundance of some alcohols showed any consistent response to the sound treatments. These results show that the application of audible sound via underwater transmission to a beer fermentation elicited limited changes to wort gravity and VOCs during fermentation.


Asunto(s)
Cerveza/análisis , Fermentación , Saccharomyces cerevisiae/crecimiento & desarrollo , Sonido , Compuestos Orgánicos Volátiles/análisis , Recuento de Células , Ésteres/análisis , Concentración de Iones de Hidrógeno , Análisis de Componente Principal , Saccharomyces cerevisiae/citología
17.
Foods ; 10(11)2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34828985

RESUMEN

Taste perception plays an undisputed role in food choice, preference, and intake. Recent literature suggests that individual diet and taste sensitivity may have a reciprocal relationship, with evidence highlighting that specific diets can alter taste sensitivities. Commensurate with an increase in the prevalence of plant-based diets is the importance of investigating if following a vegetarian or vegan diet is associated with altered taste sensitivities. In this study, the taste detection thresholds for six compounds (i.e., sweet-sucrose, salty-sodium chloride, sour-citric acid, umami-monosodium glutamate, MSG, bitter-caffeine, and metallic-iron II sulphate heptahydrate) were measured for a total of 80 healthy, New Zealand European females aged 18-45 years old, who were categorised as 22 vegans, 23 vegetarians, and 35 omnivores. Each participant's detection thresholds to these compounds were measured across two sessions, using an ascending Method of Limits with two-alternative-forced-choice presentations. The threshold data were analysed using both multivariate (i.e., principal component analysis) and univariate (i.e., ANCOVA) techniques to assess differences across the three types of diet. Multivariate analysis suggested that the omnivore group had distinct taste sensitivity patterns across the six compounds compared to the vegetarian or vegan group, which were characterised by relatively heightened sensitivity to metallic and lowered sensitivity to sweetness. Furthermore, the vegetarian group was shown to have a significantly lower detection threshold to bitterness (i.e., caffeine) relative to the other two groups (p < 0.001). While future study is required to investigate the cause-effect relationship between individual diet and taste sensitivities, the present study provides a systematic evaluation of taste sensitivities of individuals following distinct diets. This information may be valuable to future gustatory research as well as to food manufacturers.

18.
Foods ; 10(8)2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34441456

RESUMEN

Based on unsteady state heat conduction, a mathematical model has been developed to describe the simultaneous heat and moisture transfer during potato frying. For the first time, the equation was solved using both enthalpy and Variable Space Network (VSN) methods, based on a moving interface defined by the boiling temperature of water in a potato disc during frying. Two separate regions of the potato disc namely fried (crust) and unfried (core), were considered as heat transfer domains. A variable boiling temperature of the water in potato discs was required as an input parameter for the model as the water is evaporated during frying, resulting in an increase in the soluble solid concentration of the potato sample. Pulsed electric field (PEF) pretreatment prior to frying had no significant effect on the measured moisture content, thermal conductivity or frying time compared to potatoes that did not receive a PEF pretreatment. However, a PEF pretreatment at 1.1 kV/cm and 56 kJ/kg reduced the temperature variation in the experimentally measured potato center by up to 30%. The proposed heat and moisture transfer model based on unsteady state heat conduction successfully predicted the experimental measurements, especially when the equation was solved using the enthalpy method.

19.
Foods ; 10(6)2021 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-34201350

RESUMEN

This study assessed if Chinese consumer attitudes towards a range of lamb attributes (such as origin, food safety, appearance, taste, price), and their opinions of New Zealand lamb (9- and 7-point Likert scales, respectively), had changed since the outbreak COVID-19. The same survey was carried out in Shanghai and Beijing pre (December 2018) and post COVID-19 (November 2020), ~9 months after China's initial outbreak, with 500 and 523 consumers, respectively. From December 2018 to November 2020, there was an increase in the proportion of Chinese consumers purchasing red meat online or from a butcher, and cooking their lamb well-done. In contrast, there were minimal differences in Chinese consumer ratings between December 2018 and November 2020 for different lamb attributes and opinions of New Zealand lamb. Cluster analysis revealed that many consumers (140 in December 2018/376 in November 2020) used only a small portion of the high end of the scale when rating lamb attributes, resulting in little differences between the attributes. This study suggests COVID-19 has enhanced some food safety related behaviors but had little effect on Chinese opinions and preferences for New Zealand lamb attributes. It also highlights that survey design should be carefully considered when collecting responses from Chinese consumers.

20.
Food Chem ; 347: 128955, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33486360

RESUMEN

Understanding which volatile compounds discriminate between products can be useful for quality, innovation or product authenticity purposes. As dataset size and dimensionality increase, linear chemometric techniques like partial least squares discriminant analysis and variable identification (PLS-DA-VID) may not identify the most discriminant compounds. This research compared the performance of self-organizing maps and entropy-based feature selection (SOM-EFS) and PLS-DA-VID to identify discriminant compounds in 17 blue cheese varieties. A total of 172 volatiles were detected using headspace solid phase microextraction, gas chromatography and mass spectrometry, including 1-nonene and 2,6-dimethylpyridine, which were newly identified in blue cheese. Despite SOM-EFS selecting only 14 volatiles compared to 78 for PLS-DA-VID, SOM-EFS proved more effectively discriminant and improved the median five-fold cross-validated prediction accuracy of the model to 0.94 compared to 0.82 for PLS-DA-VID. These findings introduce SOM-EFS as a powerful non-linear exploratory data analysis approach in the field of volatile analytical chemistry.


Asunto(s)
Queso/análisis , Entropía , Análisis de los Alimentos/métodos , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/aislamiento & purificación , Análisis Discriminante , Cromatografía de Gases y Espectrometría de Masas , Análisis de los Mínimos Cuadrados , Microextracción en Fase Sólida
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