Browsing by Author "Singh J"

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    3D Printing of Textured Soft Hybrid Meat Analogues
    (MDPI (Basel, Switzerland), 2022-02-06) Wang T; Kaur L; Furuhata Y; Aoyama H; Singh J; Mirade PS
    Meat analogue is a food product mainly made of plant proteins. It is considered to be a sustainable food and has gained a lot of interest in recent years. Hybrid meat is a next generation meat analogue prepared by the co-processing of both plant and animal protein ingredients at different ratios and is considered to be nutritionally superior to the currently available plant-only meat analogues. Three-dimensional (3D) printing technology is becoming increasingly popular in food processing. Three-dimensional food printing involves the modification of food structures, which leads to the creation of soft food. Currently, there is no available research on 3D printing of meat analogues. This study was carried out to create plant and animal protein-based formulations for 3D printing of hybrid meat analogues with soft textures. Pea protein isolate (PPI) and chicken mince were selected as the main plant protein and meat sources, respectively, for 3D printing tests. Then, rheology and forward extrusion tests were carried out on these selected samples to obtain a basic understanding of their potential printability. Afterwards, extrusion-based 3D printing was conducted to print a 3D chicken nugget shape. The addition of 20% chicken mince paste to PPI based paste achieved better printability and fibre structure.
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    Alternative proteins vs animal proteins: The influence of structure and processing on their gastro-small intestinal digestion
    (Elsevier Ltd, 2022-04) Kaur L; Mao B; Beniwal AS; Abhilasha; Kaur R; Chian FM; Singh J
    Background: Digestibility, an indicator of protein bioavailability, is essentially a measure of the susceptibility of a protein towards proteolysis. Proteins with higher digestibility have been linked with better health outcomes. Animal proteins are generally considered to be of better nutritional value than plant proteins not only because they are a good source of essential amino acids but also due to their higher digestibility in the human gastro-intestinal tract. With the recent emergence of alternative food protein sources, which are now processed in a completely new way to design new foods or new versions of the conventional foods, it has become extremely important to understand their digestion characteristics. Scope and approach: This review discusses the factors that affect protein digestibility, including protein source, structure, type of processing, and modification, with a particular focus on the effects of non-protein components present in food matrix. Key findings and conclusions: To obtain the desired functionality, particularly for alternate proteins, numerous physical, chemical, and enzymatic methods for modification have been reported. These modifications may alter structural characteristics of proteins by inducing structural modifications such as protein unfolding, crosslinking, and aggregation. Depending upon the protein reactivity during processing, the susceptibility of proteins towards hydrolysis by digestive enzymes might change, affecting not only the overall protein digestibility but also the rates of release of polypeptides and amino acids. The faster rates of protein digestion have been linked with muscle anabolism, suggesting the need and importance of classifying the new, emerging and alternative protein sources according to their rates of digestion into rapidly (RDP), slowly digestible (SDP) and resistant (RP) proteins. More research needs to be focussed on converting, through processing, the undigestible or RP into RDP or SDP to achieve better health outcomes.
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    Cell wall permeability in relation to in vitro starch digestion of pea cotyledon cells
    (Elsevier B.V., 2024-08-07) Ajala A; Kaur L; Lee SJ; Edwards PJB; Singh J
    The role of cell wall permeability and rate of starch digestibility in intact cotyledon cells from four different varieties of pea seeds was studied. Pulsed-field gradient nuclear magnetic resonance (PFG NMR) coupled with light and confocal microscopy were employed to evaluate the cotyledon cells' diffusion coefficients and cell wall permeability. The cotyledon cells' diffusion coefficients and cell wall permeability followed a decreasing trend: White/yellow pea > Marrowfat pea > Maple pea > Blue pea. The varying size of internal cavities in the microstructure in the cotyledon cells, as observed by the light and confocal micrographs, may be responsible for this trend. The extent of starch hydrolysis recorded from the cotyledon cells followed the same trend of the cell wall permeability except for Blue pea cotyledon cells. Thus, indicating that the more permeable the cotyledon cell to the starch-degrading enzymes, the higher the extent of intracellular starch hydrolysis. The microstructure changes in the cotyledon cells during digestion also confirmed this observation.
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    Conformational changes and product quality of high-moisture extrudates produced from soy, rice, and pea proteins
    (Elsevier Ltd, 2024-02) Mao B; Singh J; Hodgkinson S; Farouk M; Kaur L
    This study aimed to investigate the performance of soy, pea, and rice proteins during high-moisture extrusion (HME) to understand better how the plant proteins transform into a fibrous structure. It found that rice protein isolate formed weak structures with the fewest layers and fibrous structures. Extruded pea protein concentrate produced more obviously layered structures than extruded soy and rice samples. Extruded soy protein isolate showed a compact gel structure, whereas extruded soy protein concentrate showed a thin fibrous structure. Meanwhile, the chewiness of soy and pea protein extrudates surpassed that of rice protein extrudates by approximately 10 N. After undergoing HME processing, there was a marked 5–10% decrease in extracted proteins (p < 0.05) in solvents with urea, dithiothreitol, and sodium dodecyl sulphate, when comparing the soy and pea extrudates with their raw materials, except for the extruded rice protein isolate (ERPI) with rice protein isolate. It could be deduced that HME processing promoted the formation of aggregates in soy and pea proteins that the extracted solvents could not dissolve. It also revealed that HME induced an increase in the content of S–S bonds in extruded soy and pea protein but a decrease in ERPI. The percentage of random coils in commercial pea protein, initially at 14.04%, saw a significant increase to 19.36% after extrusion (p < 0.05), indicating that pea protein is more likely to form intermolecular hydrogen bonds. In this study, the secondary structures of rice and soy protein did not show significant changes after extrusion.
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    Cooking of short, medium and long-grain rice in limited and excess water: Effects on microstructural characteristics and gastro-small intestinal starch digestion in vitro
    (Elsevier Ltd, 2021-07) Tamura M; Kumagai C; Kaur L; Ogawa Y; Singh J
    The purpose of present study was to investigate the impact of cooking methods on starch hydrolysis of rice grain using an in vitro digestion model. Three varieties of short, medium and long-grain rice were cooked in two different ways: in limited water method (LWM) using a rice cooker and excess water method (EWM) using a pan. The water absorption of raw rice grain was found to differ among the different rice varieties. The moisture, crude protein, total starch and resistant starch contents of the grain were affected by the cooking method. Starch hydrolysis for medium and long-grain rice at 210 min was higher for rice cooked through LWM (75.1 and 87.5%, respectively) than those cooked using the EWM (65.8 and 64.5%, respectively). Microscopic observations of grain cooked through LWM and EWM showed that the former had bigger voids present throughout the grain and had more cell wall damage than the latter, confirming that the microstructural characteristics were responsible for better enzyme accessibility and higher starch hydrolysis. These results revealed that the starch digestibility of rice grain cooked through different methods was affected by the disruption of the tissue structure that was dependent on the cooking method.
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    Development and characterisation of plant and dairy-based high protein Chinese steamed breads (mantou): Physico-chemical and textural characteristics
    (Elsevier BV, 2022-12) Mao S; Kaur L; Mu T-H; Singh J
    High protein versions of popular, highly consumed food products such as Chinese steamed bread (CSB) can be useful to improve the health status of our populations. In the current study, high protein Chinese steamed breads (HPCSBs) were developed using plant (soy protein isolate, SPI) or dairy (rennet casein, RC and milk protein concentrate, MPC) proteins. These proteins were blended into wheat flour at two different levels (RC I, RC II; SM (soy protein isolate-SPI + milk protein concentrate-MPC) I, SM II) to prepare breads, which were then compared to a control (100% wheat flour-based) Chinese steamed bread for physico-chemical and textural characteristics. The addition of proteins darkened the colour of HPCSBs and decreased the specific bread volume with RC II showing the lowest. All the high protein formulations recorded an increase in RVA pasting temperature, whereas a decrease in the peak, final and breakdown viscosities of pastes was observed with the addition of both RC and SM at all levels. Similarly, the DSC onset transition temperatures were observed to increase when either RC or SM was added to the formulation. The textural characteristics of HPCSBs showed an increase in hardness, gumminess, and resistance for penetration along with tensile strength than the control CSB.
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    Effects of microwave processing in comparison to sous vide cooking on meat quality, protein structural changes, and in vitro digestibility
    (Elsevier Ltd, 2024-02-15) Gawat M; Boland M; Chen J; Singh J; Kaur L
    This study investigated the effect of industrial microwave (MW) processing, and sous vide (SV) on goat and lamb biceps femoris, where samples were cooked to the same tenderness. The cooked meat quality and ultrastructure were analyzed along with determining the protein surface hydrophobicity, particle size distribution, secondary structure, and protein digestibility. MW-processing resulted in higher cooking loss and more ultrastructural damage than SV and also induced higher myofibrillar protein surface hydrophobicity. Both processes caused a significant increase (p < 0.05) in the β-sheet and an increase in the random coils with a reduction (p < 0.05) in α-helix and β-turns. Both processes led to different protein hydrolysis patterns (observed through SDS-PAGE), but overall free amino N release after digestion was not significantly different among them. The results suggest that MW and SV modify meat protein structure differently, but with the same meat tenderness level, these processes can lead to similar overall protein digestibility.
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    Encapsulation of Lactobacillus gasseri: Characterization, Probiotic Survival, In Vitro Evaluation and Viability in Apple Juice
    (MDPI (Basel, Switzerland), 2022-03-02) Varela-Pérez A; Romero-Chapol OO; Castillo-Olmos AG; García HS; Suárez-Quiroz ML; Singh J; Figueroa-Hernández CY; Viveros-Contreras R; Cano-Sarmiento C; Bekatorou A
    The development of functional foods containing probiotic bacteria has become increasingly relevant to improve and maintain health. However, this is often limited to dairy food matrices given the complexity involved in maintaining a stable system together with high microbial viability in matrices such as juices. The objective of this study was to develop and characterize sodium alginate capsules loaded with Lactobacillus gasseri ATCC® 19992 ™ (LG). Cell viability under in vitro gastrointestinal conditions and during storage in apple juice were evaluated. The capsules were prepared by ionic gelation and an emulsification process was performed as pretreatment using two homogenization methods: magnetic stirring (AM) and Ultraturrax® rotor-stator homogenizer (UT). Cell viability after encapsulation was similar in the two processes: 65%. At the end of the in vitro gastrointestinal evaluation, the non-encapsulated probiotic cells did not show any viability, while the AM system was able to retain 100% of its viability and the UT retained 79.14%. The morphology of the capsules consisted of a continuous and homogeneous surface. Cell viability of LG encapsulated in apple juice stored at 4 °C for 21 days was 77% for AM, 55.43% for UT, and 63.10% for free LG.
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    Functional Food Based on Potato
    (MDPI (Basel, Switzerland), 2023-05-26) Xu J; Li Y; Kaur L; Singh J; Zeng F; Krastanov AI
    Potato (Solanum tuberosum L.) has gradually become a stable food worldwide since it can be a practical nutritional supplement and antioxidant as well as an energy provider for human beings. Financially and nutritionally, the cultivation and utility of potatoes is worthy of attention from the world. Exploring the functionality and maximizing the utilization of its component parts as well as developing new products based on the potato is still an ongoing issue. To maximize the benefits of potato and induce new high-value products while avoiding unfavorable properties of the crop has been a growing trend in food and medical areas. This review intends to summarize the factors that influence changes in the key functional components of potatoes and to discuss the focus of referenced literature which may require further research efforts. Next, it summarizes the application of the latest commercial products and potential value of components existing in potato. In particular, there are several main tasks for future potato research: preparing starchy foods for special groups of people and developing fiber-rich products to supply dietary fiber intake, manufacturing bio-friendly and specific design films/coatings in the packaging industry, extracting bioactive proteins and potato protease inhibitors with high biological activity, and continuing to build and examine the health benefits of new commercial products based on potato protein. Notably, preservation methods play a key role in the phytochemical content left in foods, and potato performs superiorly to many common vegetables when meeting the demands of daily mineral intake and alleviating mineral deficiencies.
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    Goat Meat: Production and Quality Attributes
    (MDPI (Basel, Switzerland), 2023-08-21) Gawat M; Boland M; Singh J; Kaur L; Kong B
    Goat meat could be a sustainable source of red meat. Its farming requires minimal input, is suitable for free-range farming, and produces a healthier red meat option as it is lean. Although goat meat has advantages for meat production, it still needs to be established as a valuable part of the meat trade market. But, currently, goat meat production is less specialized; there is less intense breed selection for premium meat production, and often the animals are farmed with a multifunctional purpose, such as for their meat, fiber, and milk. The less structured goat meat industry contributes to the inconsistent quality of goat meat. This paper attempts to describe the characteristics of popular goat breeds and indigenous goats as a source of meat and the potential of various goat breeds for meat production. Additionally, this paper presents goat meat's quality and physicochemical and sensory attributes that are relevant to understanding the unique attributes of goat meat. Much work is needed for the goat meat processing industry to develop its potential.
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    High Protein Yangyu jiaotuan (洋芋搅团): In Vitro Oral-Gastro-Small Intestinal Starch Digestion and Some Physico-Chemical, Textural, Microstructural, and Rheological Properties
    (MDPI (Basel, Switzerland), 2023-06-23) Zeng F; Abhilasha A; Chen Y; Zhao Y; Liu G; Kaur L; Singh J; Rodríguez‑García ME
    Biomimetic foods are expected to have potential health benefits for the management and prevention of chronic diseases, such as diabetes and cardiovascular disease. In the current research, two commercially available and affordable plant proteins (soy protein isolate-SPI and pea protein isolate-PPI) at two levels (5%, 10%) were added to the Yangyu jiaotuan with the objective of developing a product with reduced glycaemic properties and high protein content while maintaining its original taste and texture. The results showed that several important textural properties such as hardness and chewiness did not change significantly during the refrigerated storage. The storage modulus G' increased with refrigerated storage time for different samples, but there were significant differences among the five samples (with and without protein addition) with respect to frequency dependence during rheological measurements. The in vitro starch digestion experiments showed that the starch hydrolysis of Yangyu jiaotuan decreased considerably (by up to 42.08%) with the increase in PPI content and during refrigerated storage due to starch retrogradation. Protein has protected the microstructure and there was less damage when compared to samples without protein. The bimodal peaks of the particle size distribution curves showed that the newly developed Yangyu jiaotuan contains two different sizes of particles; the smaller particles (~30 μm) corresponded to PPI and starch granules, while the larger particles corresponded to the fragments of the gel network of the starch matrix. Based on the above results, Yangyu jiaotuan mixed with pea protein is a convenient potato staple food product, which complies with the biomimetic potato food very well.
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    Hybrid Paneer: Influence of mung bean protein isolate (Vigna radiata L.) on the texture, microstructure, and in vitro gastro-small intestinal digestion
    (Elsevier Ltd, 2024-02-15) Tojan S; Kaur L; Singh J
    Replacing dairy proteins with legume proteins such as mung bean protein can create hybrid cheese alternatives with superior nutritional and functional properties. The effects of partially replacing (30%) cow milk with mung bean protein isolate (MBPI) on the rheology, texture, microstructure, and digestibility of paneer (acid-heat coagulated cheese) were studied. The developed hybrid cow milk-mung bean paneer (CMMBP) had higher protein and moisture contents, lower fat content, and a darker colour than cow milk paneer (CMP). CMMBP showed a significant reduction in hardness, cohesiveness, chewiness, and springiness compared to the cow milk-based control. Frequency sweeps performed using a dynamic rheometer showed higher storage modulus (G') for CMMBP compared to CMP, indicating greater elastic properties of the hybrid paneer. In vitro digestibility of CMMBP was significantly lower than CMP, as shown by the lower overall ninhydrin-reactive free amino N release and the presence of resistant peptides at the end of digestion.
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    Multitarget preservation technologies for chemical-free sustainable meat processing
    (Wiley Periodicals LLC on behalf of Institute of Food Technologists, 2022-10-19) Kaur R; Kaur L; Gupta TB; Singh J; Bronlund J
    Due to the growing consumer demand for safe and naturally processed meats, the meat industry is seeking novel methods to produce safe-to-consume meat products without affecting their sensory appeal. The green technologies can maintain the sensory and nutritive characteristics and ensure the microbial safety of processed meats and, therefore, can help to reduce the use of chemical preservatives in meat products. The use of chemical additives, especially nitrites in processed meat products, has become controversial because they may form carcinogenic N-nitrosamines, a few of which are suspected as cancer precursors. Thus, the objective of reducing or eliminating nitrite is of great interest to meat researchers and industries. This review, for the first time, discusses the influence of processing technologies such as microwave, irradiation, high-pressure thermal processing (HPTP) and multitarget preservation technology on the quality characteristics of processed meats, with a focus on their sensory quality. These emerging technologies can help in the alleviation of ingoing nitrite or formed nitrosamine contents in meat products. The multitarget preservation technology is an innovative way to enhance the shelf life of meat products through the combined use of different technologies/natural additives. The challenges and opportunities associated with the use of these technologies for processing meat are also reviewed.
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    Physico-Chemical Characteristics and In Vitro Gastro-Small Intestinal Digestion of New Zealand Ryegrass Proteins
    (MDPI (Basel, Switzerland), 2021-02-04) Kaur L; Lamsar H; López IF; Filippi M; Ong Shu Min D; Ah-Sing K; Singh J; Moreno FJ
    Being widely abundant, grass proteins could be a novel source of plant proteins for human foods. In this study, ryegrass proteins extracted using two different approaches-chemical and enzymatic extraction, were characterised for their physico-chemical and in vitro digestion properties. A New Zealand perennial ryegrass cultivar Trojan was chosen based on its higher protein and lower dry matter contents. Grass protein concentrate (GPC) with protein contents of approximately 55 and 44% were prepared using the chemical and enzymatic approach, respectively. The thermal denaturation temperature of the GPC extracted via acid precipitation and enzymatic treatment was found to be 68.0 ± 0.05 °C and 66.15 ± 0.03 °C, respectively, showing significant differences in protein's thermal profile according to the method of extraction. The solubility of the GPC was highly variable, depending on the temperature, pH and salt concentration of the dispersion. The solubility of the GPC extracted via enzymatic extraction was significantly lower than the proteins extracted via the chemical method. Digestion of raw GPC was also studied via a gastro-small intestinal in vitro digestion model and was found to be significantly lower, in terms of free amino N release, for the GPC prepared through acid precipitation. These results suggest that the physico-chemical and digestion characteristics of grass proteins are affected by the extraction method employed to extract the proteins. This implies that selection of an appropriate extraction method is of utmost importance for achieving optimum protein functionality during its use for food applications.
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    Preparation and characterisation of plant and dairy-based high protein Chinese steamed breads (mantou): Microstructural characteristics and gastro-small intestinal starch digestion in vitro
    (Elsevier BV, 2023-12-23) Mao S; Kaur L; Mu T-H; Singh J
    The effects of dairy and plant protein addition on microstructural characteristics and in vitro gastro-small intestinal starch digestion characteristics of Chinese steamed breads (CSBs) were studied. Breads containing rennet casein (RC) and a mixture of soy protein isolate and milk protein concentrate (SM) at two different levels (RC I, RC II; SM I, SM II) were prepared. Microstructural characteristics of the undigested and digested control (100% wheat flour) bread and high protein steam bread (HPCSB) versions were compared through scanning electron microscopy. The compact microstructure of HPCSBs displayed a network of proteins wrapped around starch granules and had fewer air cells compared to the control. The addition of both proteins influenced the microstructure of HPCSBs, which in turn affected their textural and starch digestion properties. The in vitro starch digestion of control CSB and HPCSBs confirmed that the addition of proteins is capable of lowering the starch hydrolysis (%). The highest starch hydrolysis was observed for the control wheat bread, followed by SM1 > RC I > SM II and RC II at the end of the small-intestinal digestion. The estimated glycaemic indices (eGI) for all HPCSBs were statistically lower than the control CSB. In comparison to control CSB, the microstructure of HPCSBs appeared more irregular, less porous, and compact during gastric and small intestinal digestion.
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    Probing the Double-Layered Cotyledon Cell Structure of Navy Beans: Barrier Effect of the Protein Matrix on In Vitro Starch Digestion
    (MDPI (Basel, Switzerland), 2023-01) Do DT; Singh J; Johnson S; Singh H; Bordoni A
    The microstructure of legumes plays a crucial role in regulating starch digestion and postprandial glycemic responses. Starch granules are double encapsulated within the outer cell wall and the inner protein matrix of legume cotyledon cells. Despite progress in understanding the role of cell walls in delaying starch digestion, the role of the protein matrix has received little research attention. The aim of this study was to evaluate if the protein matrix and cell wall may present combined physical barriers retarding enzyme hydrolysis of intracellular starch. Intact cotyledon cells were isolated from navy beans and used to assess the barrier effect of the protein matrix on the digestion of starch under conditions simulating the upper gastrointestinal tract. The cells were pretreated with pepsin at 37 °C and pH 2.0 for 1, 4, or 24 h and without pepsin for 24 h (control) to facilitate removal of the intracellular protein matrix prior to cooking and simulated in vitro digestion. A longer pretreatment time resulted in a lower protein content of the cells and a higher initial rate and extent of starch hydrolysis. We suggest that in addition to the primary cell wall barrier, the protein matrix provides a secondary barrier restricting the accessibility of α-amylase to starch. This study provides a new fundamental understanding of the relationship between the structural organization of legume cotyledon cells and starch digestion that could inform the design of novel low glycemic index foods.
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    Protein Nutrition: Understanding Structure, Digestibility, and Bioavailability for Optimal Health.
    (MDPI (Basel, Switzerland), 2024-06-05) Ajomiwe N; Boland M; Phongthai S; Bagiyal M; Singh J; Kaur L; Wei Z
    This review discusses different protein sources and their role in human nutrition, focusing on their structure, digestibility, and bioavailability. Plant-based proteins, such as those found in legumes, nuts, and seeds, may contain anti-nutritional factors that impact their bioavailability apart from structural and compositional differences from animal proteins. Animal proteins are generally highly digestible and nutritionally superior to plant proteins, with higher amino acid bioavailability. Alternative protein sources are also processed in different ways, which can alter their structure and nutritional value, which is also discussed.
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    Rice Germination and Its Impact on Technological and Nutritional Properties: A Review
    (Elsevier BV on behalf of the China National Rice Research Institute, 2022-05-06) do Nascimento LÁ; Abhilasha A; Singh J; Elias MC; Colussi R
    Grain germination is a process involving numerous factors that influence the biochemical processes inside the plant cells. This review covered the abiotic factors that lead to the germination and significantly impact the nutritional properties and digestion behavior of rice grains. The macro- and micro-nutrients can be changed depending on the intensity of the applied variables during germination. For instance, germination time can increase the protein content in the grain and concurrently reduce its protein digestibility. In most cases, the number of bioactive compounds present in rice grains are increased regardless of germination conditions. Germination can promote the complexation of nutrients and thus negatively interfere with the digestibility of macronutrients. This review highlighted the influence of the germination process on the nutritional quality of rice grains, providing information about the germination conditions and their impacts on the anabolic and catabolic reactions of the grain, emphasizing the health benefits.
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    Synthesis and characterisation of Mānuka and rosemary oil-based nano-entities and their application in meat
    (Elsevier Ltd, 2024-03-15) Kaur R; Gupta TB; Bronlund J; Singh J; Kaur L
    Mānuka (MO) and rosemary oils (RO) -containing nanoemulsions and nanocapsules made of sodium alginate and whey protein, were designed and compared for their antioxidant effect. Mānuka oil-nanoemulsions and nanocapsules had smaller particle sizes (343 and 330 nm), less negative zeta potential (-12 mV and -10 mV), higher phenolic content, and antiradical characteristics than RO-nano-entities. However, nano-entities of both oils showed more thermostability and sustained release than free oils. Further, the antioxidant effect of essential oils and their nano-entities was compared against sodium nitrite (SN)-added and without antioxidants-added (controls) and Wagyu and crossbred beef pastes (14 days refrigerated storage). No significant difference among MO, RO and their nano-entities was noticed in crossbred pastes, while in Wagyu, nanoemulsions showed the lowest oxidation values than controls and SN-added pastes. Hence, nano-entities can be alternatives to chemical preservatives as natural antioxidants in meat preservation, along with improved thermal stability and release than free oils.
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    Understanding the Mechanism of How Pulsed Electric Fields Treatment Affects the Digestibility and Characteristics of Starch in Oat Flour
    (MDPI (Basel, Switzerland), 2022-10-13) Duque SMM; Leong SY; Agyei D; Singh J; Larsen N; Sutton K; Oey I; Cozzolino D
    The objective of this study was to evaluate the effect of pulsed electric fields (PEF) on the in vitro starch digestibility properties of oat flour. A wide range of PEF process intensity was investigated (electric field strength between 2.1 and 4.5 kV/cm and specific energy inputs between 52 and 438 kJ/kg using 20 μs square wave bipolar pulse at 100 Hz). The results revealed that PEF applied at a high electric field strength and energy <216 kJ/kg was favourable in slowing down the rate of starch digestibility (by 48%) during in vitro gastrointestinal digestion. This is accompanied by a significant decrease (from 15% to 7–10%) in the proportion of rapidly digestible starch (RDS) and a significant increase (from 77% to 84–85%) in resistant starch (RS) fraction. The application of PEF at energy level >421 kJ/kg at any field strength intensities raised the RDS (from 15% to 19–20%), but the rate of starch digestion was not affected (maintained at 3.3–3.7 × 10−2 min−1 vs. untreated at 3.8 × 10−2 min−1). Further analysis of the structure, particle size, and thermal stability of PEF-treated oat flour through fractionation into three distinct flour segments revealed that PEF could cause major modifications in the particle size, damage and aggregation of starch granules, and destruction of the long- and short-range ordered structures of starch. Data gathered in this study indicate that PEF treatment can be a reliable strategy to modulate the in vitro starch digestibility of oat flour, either by reasonably slowing down the digestion rate or enabling a slightly higher amount of starch to be readily accessible by digestive enzymes without affecting the digestion rate.