Impact of Different Carbon Sources on Volatile Organic Compounds (VOCs) Produced during Fermentation by WLP672 Measured Using Proton Transfer Reaction Time-of-Flight Mass Spectrometry (PTR-ToF-MS).

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.

Volatile Organic Compounds (VOCs) Produced by WLP672 Fermentation in Defined Media Supplemented with Different Amino Acids.

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 WLP672 (LB672).

The Physical and Structural Effects of 1-MCP on Four Different Apple Cultivars during Storage.

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.

Online monitoring of higher alcohols and esters throughout beer fermentation by commercial Saccharomyces cerevisiae and Saccharomyces pastorianus yeast.

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 Volatiles of Fermented Vegetable and Fruit Substrates: A Review.

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.

Yeast Strain Influences the Hop-Derived Sensory Properties and Volatile Composition of Beer.

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), 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.

Direct liquid transmission of sound has little impact on fermentation performance in Saccharomyces cerevisiae.

Sound is a physical stimulus that has the potential to affect various growth parameters of microorganisms. However, the effects of audible sound on microbes reported in the literature are inconsistent. Most published studies involve transmitting sound from external speakers through air toward liquid cultures of the microorganisms.

Understanding the effect of meat electrical conductivity on Pulsed Electric Field (PEF) process parameters and the ability of PEF to enhance the quality and shorten sous vide processing for beef short ribs.

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.

Impact of sourdough culture on the volatile compounds in wholemeal sourdough bread.

Sourdough bread has a complex flavour profile, which is strongly influenced by the compounds generated during fermentation by the diverse array of microorganisms present, mainly yeasts and lactic acid bacteria (LAB). Twelve complex sourdough cultures, comprised of mixtures of yeast and bacteria, were propagated using wholemeal flour and used in the production of sourdough breads. The volatile organic compounds (VOCs) present in the sourdough bread crumb were characterised by gas chromatography-mass spectrometry (GC-MS) and proton transfer reaction-mass spectrometry (PTR-MS).

Cross-Cultural Differences in the Perception of Lamb between New Zealand and Chinese Consumers in New Zealand.

This study investigated differences between general New Zealand consumers and ethnic Chinese consumers living in New Zealand regarding the importance of lamb attributes at the point of purchase and opinions of New Zealand lamb. A central location test survey was undertaken with 156 New Zealand consumers living in Dunedin, New Zealand, and 159 Chinese consumers living in Auckland, New Zealand. In terms of importance at the point of purchase, Chinese consumers rated a number of attributes as more important than New Zealand consumers by a difference of >1.

Association of metabolomic and lipidomic data with Chinese and New Zealand consumer clusters showing preferential likings for lamb meat from three production systems.

Relationships between overall liking scores for cooked lamb from Chinese (n = 158) and New Zealand (n = 156) consumers, and metabolite and lipid profiles were evaluated. Consumers assessed meat from 6 to 8-month-old lambs of composite genetics fed chicory (CHIC) or grass (GRASS), and from 12 month-old Merino lambs fed a mixed pasture (PMER). On average, Chinese consumers rated the overall liking of all types of lamb similarly, while New Zealand consumers preferred meat from CHIC over PMER.

The Effect of Sound Frequency and Intensity on Yeast Growth, Fermentation Performance and Volatile Composition of Beer.

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.

Heat and Mass Transfer Modeling to Predict Temperature Distribution during Potato Frying after Pre-Treatment with Pulsed Electric Field.

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.

Relationships among Consumer Liking, Lipid and Volatile Compounds from New Zealand Commercial Lamb Loins.

Loin sections (m. ) were collected at slaughter from forty-eight lamb carcasses to evaluate consumer-liking scores of six types of typical New Zealand commercial lamb and to understand the possible underlying reasons for those ratings. A consumer panel ( = 160) evaluated tenderness, juiciness, flavor liking, and overall liking of the different types of lamb loins.

Gelatinisation and milling whole-wheat increases postprandial blood glucose: randomised crossover study of adults with type 2 diabetes.

Aims/hypotheses: We examined the effects of milling and cooking whole grains in water to achieve starch gelatinisation on postprandial blood glucose using a randomised crossover open-label design. Participants were adults with type 2 diabetes whose body weight or medications had not changed in at least 3 months.

Methods: Postprandial blood glucose (measured as incremental AUC [iAUC]) was measured following consumption of four nutrient-matched whole-wheat porridge test-meals.

Differences in New Zealand Hop Cultivars Based on Their Unique Volatile Compounds: An Integrated Fingerprinting and Chemometrics Approach.

Hop aroma characteristics originate from hop essential oils, which have complex chemical profiles that remain poorly understood, particularly for New Zealand hops. The aim of this study was to determine volatile compounds that distinguish New Zealand hop cultivars. Untargeted fingerprinting methods based on headspace gas chromatography mass spectrometry (GC-MS) were used to analyse nine hop cultivars.

Fatty Acid Composition and Volatile Profile of from Commercial Lambs Reared in Different Forage Systems.

Animal production factors can affect the fatty acid and volatile profile of lamb meat. The fatty acid and volatile composition of the was evaluated from 150 lambs from 10 groups of commercial lambs that differed in age, sex, diet and breed, from three farms, which represent typical forage lamb production systems in New Zealand. The meat from 4-month-old composite lambs slaughtered at weaning had a similar polyunsaturated to saturated fatty acid ratio compared to 6- to 8-month-old composite lambs, but a greater ratio than that of 12-month-old Merino lambs ( < 0.

Application of a Novel Instantized Glycerol Monooleate Ingredient in a Protein-Stabilized Oil-In-Water Emulsion.

Glycerol monooleate (GMO), casein and whey proteins are surfactants that can stabilize emulsion systems. This study investigates the impact of instantized GMO powders on creaming stability and oxidative stability in protein-stabilized emulsions. Model emulsions with bulk GMO, two instantized GMO powders, and two controls (without GMO) were produced by microfluidization.

Understanding the Frying Process of Plant-Based Foods Pretreated with Pulsed Electric Fields Using Frying Models.

Deep-fried foods (e.g., French fries, potato/veggie crisps) are popular among consumers.

Evolution of Volatile and Phenolic Compounds during Bottle Storage of Merlot Wines Vinified Using Pulsed Electric Fields-Treated Grapes.

This study aimed to elucidate changes in volatile, phenolic, and oenological profiles of wines vinified from Pulsed Electric Fields (PEF)-treated and untreated Merlot grapes during bottle storage of up to 150, 90, and 56 days at 4 °C, 25 °C, and 45 °C, respectively, through chemometrics technique. Wines produced from untreated grapes and those PEF-treated at four different processing conditions (electric field strength 33.1 and 41.

Genotype-by-environment interaction in coast redwood outside natural distribution - search for environmental cues.

Background: Effective matching of genotypes and environments is required for the species to reach optimal productivity and act effectively for carbon sequestration. A common garden experiment across five different environments was undertaken to assess genotype x environment interaction (GxE) of coast redwood in order to understand the performance of genotypes across environments.

Results: The quantitative genetic analysis discovered no GxE between investigated environments for diameter at breast height (DBH).

Feasibility of using integrated fingerprinting, profiling and chemometrics approach to understand (bio) chemical changes throughout commercial red winemaking: A case study on Merlot.

This study assessed the feasibility of using a multiplatform approach; integrating untargeted fingerprinting of volatiles and targeted profiling of phenolic and oenological attributes (soluble solids, pH, titratable acidity and colour properties) coupled with chemometrics to understand complex (bio) chemical reactions occurring during Merlot red winemaking. The changes were investigated at three winemaking stages, starting from pre-maceration (PM), maceration-alcoholic fermentation (MAF) up to completion of malolactic fermentation (MLF). Merlot musts at PM were characterised by lighter colour and higher amount of green aroma-related volatiles.

Wholegrain Particle Size Influences Postprandial Glycemia in Type 2 Diabetes: A Randomized Crossover Study Comparing Four Wholegrain Breads.

Objective: Wholegrain foods vary in the extent of processing. We investigated whether wholegrain particle size in bread influences postprandial glycemia in type 2 diabetes.

Research Design And Methods: Postprandial glycemia (incremental area under the blood glucose curve [iAUC]) was measured after consumption of three breads made with roller-milled wholegrain flour and added grains and a fourth made with stone-ground flour.

Bacterial survival and adhesion for formulating new oral probiotic foods.

Probiotics are defined as live microorganisms, which, when administered in adequate amounts, confer health benefits to the host. Traditionally, probiotic food research has heavily focused on the genera and , along with their benefits for gut health. Recently with the identification of new probiotic strains specifically intended for oral health applications, the development of probiotic foods for oral health benefits has garnered interest, with a renewed focus on identifying new food formats for delivering probiotics.

Changes in the physicochemical properties and flavour compounds of beef bone hydrolysates after Maillard reaction.

This study investigated the changes in physicochemical properties and volatile compounds of beef bone hydrolysates during heat treatment as a result of the Maillard reaction (MR). Five beef bone hydrolysates obtained from single (P-Protamex®, B-bromelain, and F-Flavourzyme®) and simultaneous (P + F and B + F) enzymatic hydrolysis treatments were combined with ribose in aqueous solutions and heated at 113 °C to produce Maillard reaction products (MRPs). Total free amino acids decreased after heat treatment indicating the occurrence of the MR.