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Summary: This study aimed to produce chitin nanocrystals (CHNC) from mushroom and investigate their potential application in improving physicochemical properties of starch edible films. Alpha‐Chitin was extracted by demineralisation, deproteination, and discoloration treatments of mushroom powder, while CHNC were obtained by acid hydrolysis. Hydrolysis using hydrochloric acid for 120 min at concentration of 3 m was selected as the best conditions for CHNC. X‐ray Diffraction Analysis and Transmission Electron Microscopy showed a crystallinity index of 77 ± 1.2% and needle‐like morphology for CHNC with an average length of 81 nm and diameter of 19 nm. Chemical, morphological, and thermal properties of CHNC were characterised using FTIR, SEM, and DSC analysis and results indicated an increase of the purity of CHNC after hydrolysis. Different concentrations of CHNC (1, 3, 5, and 7% W/W) were used to produce a nanocomposite green film from corn starch. Quantification of the mechanical properties of the green films documented a direct relationship between CHNC concentration and the samples tensile strength and Young's modulus. However, increasing CHNC concentration resulted in a reduction in the samples' water vapour permeability, water solubility, and moisture absorption. The results of this study are promising, suggesting enhancements in the physicochemical properties of the edible film through CHNC incorporation. [ABSTRACT FROM AUTHOR]

Increasing the use of plant proteins in foods requires improving their physical and chemical properties, such as emulsification, gelation capacity, and thermal stability. These properties determine the acceptability and functionality of food products. Higher protein solubility significantly impacts these properties by affecting denaturation and the stability of emulsifiers or gels. Therefore, developing plant-based protein ingredients requires accurately and conveniently measuring their solubility. Colorimetric solubility methods overcome many issues of more robust combustion and titration methods, but complicated chemical mechanisms limit their applicability for certain proteins. This study aims to compare the effectiveness of four common colorimetric solubility measurement methods for pulse and non-pulse legume proteins and hydrolysates. Pea, chickpea, lentil, and soy protein isolates were made from defatted flour and their solubility at a range of pHs was measured using the Bradford, Lowry, bicinchoninic acid (BCA), and biuret methods. Solubility was also measured for chickpea and soy protein hydrolysates made using Alcalase and Flavourzyme. A comparison of the methods for solubility quantification revealed that the Bradford and Lowry methods most closely match the expected results for the unhydrolyzed protein, with the BCA and biuret methods underestimating solubility by 30%. The Lowry method was the preferred method for hydrolysate solubility measurement, with the Bradford method measuring 0% solubility at the isoelectric point due to an inability to interact with peptides that are soluble at this pH. This study identifies reliable methods for measuring plant protein solubility that establish uniform outcomes and enable a better comparison across studies, giving a consensus for key functional properties in food applications. [ABSTRACT FROM AUTHOR]

Summary: Food waste by‐products contain many bioactive compounds, such as proteins, carbohydrates, polyphenols and carotenoids. The purposes of this study was to extract oleoresin from tomato waste, apply tomato pomace powder (TPP) as a new shell material for encapsulation of oleoresin and to fortify orange juice using the developed microcapsules. Microencapsulation was carried out based on different TPP (2% and 3%) and oleoresin (20% and 30%) concentrations by spray drying at two temperatures (130 and 140 °C). Different features of microcapsules such as the encapsulation load, encapsulation efficiency, moisture content, hygroscopicity, bulk and tapped densities and the Hausner ratio were analysed. Based on properties of microcapsules, samples containing 3% TPP and 30% oleoresin dried at 130 °C were selected as the best treatment and their characteristics such as morphology, chemical structure and thermal behaviour were investigated. Scanning electron microscopy indicated that spherical micron‐size particles were formed and their crack‐free fine surface showed their potential for encapsulation of anti‐oxidants to reduce oxygen diffusion. Microencapsulated oleoresin was then added to the orange juice and the samples' pH, acidity, total soluble solids and colour were evaluated and compared with pure orange juice. Free radical scavenging method was used to investigate the anti‐oxidant properties of orange juice during storage. The results indicated that at the end of the 30 days of storage the fortified orange juice had anti‐oxidant activity equal to pure fresh orange juice on day one. Sensory evaluation results showed no significant differences between appearance, colour, thickness and overall acceptance of fresh and the fortified juices (P < 0.05). The results of this study showed the potential application of food and agricultural waste in production of value‐added ingredients to be used as natural additives in food industries. [ABSTRACT FROM AUTHOR]

This paper identifies physical properties of an interesterified palm‐based fat (EIEPO) that predict oil binding capacity (OBC). A 100% EIEPO sample, 50% EIEPO sample diluted with 50% soybean oil (SBO), and a 20% EIEPO sample diluted with 80% SBO were used to test how saturation level impacts OBC. All samples were crystallized using either a fast (6.4°C/min) or slow (0.1°C/min) cooling rate as well as with or without the application of high‐intensity ultrasound (HIU; 20 kHz) to generate a wide range of physical properties. Immediately after crystallization, the sample's physical properties, including crystal microstructure, solid fat content (SFC), viscoelasticity (G′, G″, and δ), melting behavior, hardness, and OBC (centrifuge method) were quantified. The samples were then stored for 48 h at 22 and 5°C and the aforementioned physical properties were measured again, with one additional measurement for the samples stored at 5°C—OBC using a filter paper method (OBCp). The results indicate that OBC can be optimized in a palm‐based fat by modifying the physical properties which was achieved via the processing conditions. Both measurements of OBC were significantly correlated with SFC, hardness, δ, and enthalpy. A model was developed to predict a sample's OBCc using the following dominant variables—SFC, hardness, peak temperature, enthalpy, and the number of crystals. These results suggest that OBC can be predicted using a sample's SFC, hardness, peak temperature, enthalpy, and number of crystals and that SFC, hardness, and enthalpy are main drivers of OBC. [ABSTRACT FROM AUTHOR]

Plant-based protein ingredients are an emerging solution to the environmental and health issues associated with animal-based proteins. Pulses have become a promising source of these plant-based ingredients. In order to produce functional proteins from pulse grains, extensive processing must be conducted to extract their proteins. These processing steps have consequential effects on the composition and structure of the resulting proteins which may modify their functional properties. This study reviews the most prominent options for each unit operation of pulse protein processing such as extraction, isolation, and drying. It also emphasizes the benefits and drawbacks of such methods and their effects on the pulse protein functionality. Furthermore, enzymatic hydrolysis is discussed as an optional processing step that is thought to counteract loss of functionality associated with pulse protein isolation. However, review of enzymatic hydrolysis literature reveals methodological issues in which insoluble and nonfunctional fractions of pulse protein hydrolysates are removed before analysis. This literature may draw into question the validity of the conventional wisdom that enzymatic hydrolysis is always beneficial to protein functionality. [ABSTRACT FROM AUTHOR]

Accurate prediction of growth of undesirable organisms (e.g., Pseudomonas fluorescens) in perishable foods (e.g., milk), held under sub-ideal storage conditions, can help ensure the quality and safety of these foods at the point of consumption. In this investigation, we inoculated sterile milk with P. fluorescens (∼103 cfu/ mL) and monitored inoculum growth behavior at constant and fluctuating storage temperatures. Three storage temperatures, 4°C, 15°C and 29°C, were selected to simulate proper refrigeration conditions (4°C) and temperature abuse, respectively. To simulate temperature fluctuation, milk held at 4°C was subjected to temperature shifts to 15°C or 29°C for 4 to 6 h. A modified logistic model was used to obtain the best-fit curve for the microbial growth under constant storage temperature. The specific growth rates at 4°C, 15°C, and 29°C, obtained from experimental data, were 0.056 ± 0.00, 0.17 ± 0.05, and 0.46 ± 0.02 h-1, respectively, and the lag time values were 29.5 ± 4.2, 12.7 ± 4.4, and 2.8 ± 0.3 h, respectively. A model predicting bacterial growth under different temperature fluctuations was obtained using the growth parameters extracted from constant temperature experiments. Growth behavior predicted by the fluctuating temperature model and that obtained experimentally were in good agreement. Lag time exhibited a larger variation compared with specific growth rate, suggesting that it depends not only on growth temperature but also on the sample population and temperature gradient. Additionally, experimental data showed that changing the temperature during the lag phase induced an additional lag time before growth; however, no significant lag time was observed under the temperature fluctuation during the exponential phase. The results of this study provide information for precise shelf-life determination and reduction of food waste, particularly for milk and milk-containing food products. [ABSTRACT FROM AUTHOR]