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1.
J Agric Food Chem ; 72(20): 11597-11605, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38718203

ABSTRACT

The aim of the study was to investigate how smoke-associated flavoring substances behave during storage in Frankfurter-type sausages. The diffusion behavior of seven selected aroma substances in the sausage matrix and the influence of the packaging and the casing were examined over a storage period of 28 days. The sausages were cut into uniformly thick layers at defined time intervals and examined by headspace-solid phase microextraction-gas chromatography-mass spectrometry. In general, three different groups could be distinguished: (1) even distribution over the entire product on the first day after smoking; (2) clear concentration gradient from outside to inside on the first day of storage, which leveled out until day 28 of storage; and (3) a clear concentration gradient that remained present throughout the storage period. In addition, only small effects were found in the distribution of flavorings between two types of packaging, selected casing, or different calibers.


Subject(s)
Flavoring Agents , Food Packaging , Gas Chromatography-Mass Spectrometry , Meat Products , Odorants , Smoke , Food Packaging/instrumentation , Smoke/analysis , Meat Products/analysis , Odorants/analysis , Animals , Flavoring Agents/chemistry , Swine , Solid Phase Microextraction , Volatile Organic Compounds/chemistry , Diffusion , Food Storage
2.
J Food Sci ; 89(2): 1086-1097, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38224172

ABSTRACT

In the food industry, the phycobiliprotein phycocyanin acts as a color pigment or the functional part of the superfood "Spirulina." It is industrially extracted from Arthrospira platensis. Current scientific research is focusing on finding complex partners with the potential to stabilize phycocyanin against its sensitivity toward heating and pH changes. Less attention is paid to the factors that influence complexation. This study focuses on the mixing ratio of phycocyanin with pectin. Phycocyanin concentration was fixed, and the mixing ratios ranged from 0.67 to 2.50 (pectin:phycocyanin). All samples were analyzed for their color, size, microscopic structure, zeta potential, and sedimentation stability before and after heating at 85°C. It was found that increasing the pectin content fostered the initial interactions with the protein and chromophore, resulting in a color shift from blue to turquoise. The size of the complexes decreased from several micrometers to nanometers with increasing pectin concentration. Those smaller complexes that were formed at a mixing ratio of 2.5 showed a higher colloidal stability over a period of ∼2 days. It is suggested that at a low mixing ratio (0.67), phycocyanin cannot be completely entrapped within the complexes and attaches to the complex surface as well. This results in aggregation and precipitation of the complexes upon heating. With increasing aggregation and consequently size as well as density of the complexes, sedimentation was accelerated. PRACTICAL APPLICATION: Under acidic conditions, as found in many foods and beverages (e.g., soft drinks, hard candy), phycocyanin tends to agglomerate and lose its color. Specifically heating, triggers denaturation, causing phycocyanin to aggregate and lose vital protein-chromophore interactions necessary to maintain a blue color. To prevent precipitation of the phycocyanin-pectin complexes, increasing the amount of pectin to a ratio of at least 2.0 is effective. This illustrates how adjusting the mixing ratio improves stability. Conversely, lower mixing ratios  induce color precipitation, valuable in purification processes. Thus, practical use of biopolymer-complexes, requires determination of the optimal mixing ratio for the desired effect.


Subject(s)
Pectins , Phycocyanin , Heating
3.
J Food Sci ; 88(11): 4375-4387, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37807472

ABSTRACT

The effects of aging and microbial growth on the metabolome of aged beef were investigated in this study. The metabolome of beef is influenced by the aging method applied. This includes the aging-related changes in metabolism and the presence of microorganisms on the beef during aging that may affect the beef and its quality. The inner part and the trimmed surface of dry-aged (the surface of dry-aged beef is also called the "crust" due to its drying during aging) and wet-aged beef were analyzed by 1 H nuclear magnetic resonance (NMR) spectroscopy over aging periods up to 28 days at intervals of 7 days, and the former also by microbiological analysis. The metabolome detected by 1 H NMR spectroscopy demonstrated changes over the aging time of beef and differed depending on the sampling location (surface or inner part of beef). The influence of the microbiota on changes in the metabolome can be negligible due to the low microbial growth on the surface of dry-aged beef (<3 log CFU/g). Therefore, the aging-related metabolism postmortem of the analyzed dry-aged beef might be the main factor for metabolic changes. The significantly (p < 0.05) higher amino acids and inosine concentrations and lower inosine 5'-monophosphate concentrations suggested enhanced protein degradation and energy metabolism in the wet-aged beef compared to the dry-aged beef, probably due to the combined influence of the aging and the microbiota on the wet-aged beef and, thus, its metabolic changes.


Subject(s)
Desiccation , Microbiota , Animals , Cattle , Aging , Inosine
4.
Meat Sci ; 205: 109320, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37659142

ABSTRACT

This review is providing an overview of the actual and past research in the field of ground meat. The forces that are acting in the meat grinder are well understood. The higher the forces that are acting on the meat while grinding, the stronger the disintegration of the meat cells after the process. These forces can be calculated as energy transfer in meat grinders using specific mechanical energy (SME). The amount of non-intact cells (ANIC) can be used to describe the extent of disintegrated cells. Different methods are available to rate the quality of ground meat, which is mainly influenced by the raw material and processing. Over the past decades of industrialization, the landscape of ground meat production has changed. However, the effects of the process adjustments on the quality of ground meat are not yet sufficiently described in the literature.


Subject(s)
Food Quality , Meat , Animals
5.
Compr Rev Food Sci Food Saf ; 22(4): 3366-3394, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37306532

ABSTRACT

Meat color is an important aspect for the meat industry since it strongly determines the consumers' perception of product quality and thereby significantly influences the purchase decision. Emergence of new vegan meat analogs has renewed interest in the fundamental aspects of meat color in order to replicate it. The appearance of meat is based on a complex interplay between the pigment-based meat color from myoglobin and its chemical forms and light scattering from the muscle's microstructure. While myoglobin biochemistry and pigment-based meat color have been extensively studied, research on the physicochemical contribution of light scattering to meat color and the special case of structural colors causing meat iridescence has received only little attention. Former review articles focused mostly on the biochemical or physical mechanisms rather than the interplay between them, in particular the role that structural colors play. While from an economic point of view, meat iridescence might be considered negligible, an enhanced understanding of the underlying mechanisms and the interactions of light with meat microstructures can improve our overall understanding of meat color. Therefore, this review discusses both biochemical and physicochemical aspects of meat color including the origin of structural colors, highlights new color measurement methodologies suitable to investigate color phenomena such as meat iridescence, and finally presents approaches to modulate meat color in terms of base composition, additives, and processing.


Subject(s)
Iridescence , Myoglobin , Myoglobin/chemistry , Meat/analysis , Color , Consumer Behavior
6.
Food Chem ; 423: 136258, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37172502

ABSTRACT

The impact of temperature-controlled smoldering smoking conditions on the accumulations of polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HAs) in Frankfurter-type sausages was investigated. Depending on the temperature, smoking can be divided into two phases: an unstable pyrolysis stage (≈ 200 s) and a stable pyrolysis stage (>200 s), which had different effects on hazardous substances contents. The unstable pyrolysis stage, which contributed 66.9 âˆ¼ 89.6% of PAH accumulations by comparing with sausages smoked for 15 min, has significant impact on high PAH residues. By contrast, the contents of HAs showed steady increase trends with smoking time. Few types of free-HAs with low concentrations (3.05 âˆ¼ 22.9 ng/g DW), but more types of bound-HAs with much higher levels (10.8 âˆ¼ 396 ng/g DW) were found. In addition, the formation of some HAs followed the first-order reaction model. However, the detailed formation mechanisms of PAHs and HAs under temperature-controlled smoldering smoking conditions remain to be studied.


Subject(s)
Meat Products , Polycyclic Aromatic Hydrocarbons , Polycyclic Aromatic Hydrocarbons/chemistry , Temperature , Meat Products/analysis , Amines , Smoking
7.
Foods ; 12(4)2023 Feb 13.
Article in English | MEDLINE | ID: mdl-36832861

ABSTRACT

(1) Background: The selection of raw material and the postmortem processing of beef influence its quality, such as taste. In this study, the metabolome of beef from cows and heifers is examined for differences during aging. (2) Methods: Thirty strip loins from eight heifers and seven cows (breed code: 01-SBT) were cut into ten pieces and aged for 0, 7, 14, 21 and 28 days. Samples from the left strip loins were wet-aged in vacuum, while samples from right strip loins were dry-aged at 2 °C and 75% relative humidity. The beef samples were extracted with methanol-chloroform-water, and the polar fraction was used for 1H NMR analysis. (3) Results: The PCA and OPLS-DA showed that the metabolome of cows and heifers varied. Eight metabolites revealed significant differences (p < 0.05) in the samples from cows and heifers. The aging time and aging type of beef also affected the metabolome. Twenty-eight and 12 metabolites differed significantly (p < 0.05) with aging time and aging type, respectively. (4) Conclusions: The variations between cows and heifers and aging time affect the metabolome of beef. By comparison, the influence of aging type is present but less pronounced.

8.
Front Nutr ; 10: 1101479, 2023.
Article in English | MEDLINE | ID: mdl-36824169

ABSTRACT

So-called meat hybrids are a new class of products where a fraction of the meat product (e.g., 20%) is replaced with alternative protein sources, such as plant-based ones. Research suggests that these products could serve as a low-threshold offer for a specific target group that wants to cut down on meat, thereby facilitating the transition toward a more healthy and sustainable diet. Nonetheless, data demonstrate that meat hybrids with a high substantial meat substitution level often fail in the market. This study summarises findings on the physicochemical properties, sensory, and acceptance of six different meat hybrids (70% meat and 30% plant proteins) that were collected in the framework of a case study in the project AiF 196 EN. For this purpose, sensory characteristics were collected via two QDA sessions and a hedonic consumer test. Furthermore, the hybrid recipes were analysed in their proximate composition. The respective recipes varied in protein source (soybean, pumpkin, and pea) and mode of incorporation [textured vegetable protein (TVP), high moisture extrudate (HME)]. It was shown that a meat hybrid with a relatively high share of 30% plant-based proteins with peas as a protein source and TVP as a processing method can still attract consumers.

9.
Food Sci Technol Int ; 29(2): 151-155, 2023 Mar.
Article in English | MEDLINE | ID: mdl-34939455

ABSTRACT

The effect of Hofmeister salts (NaCl, NaSCN, Na2SO4, KCl, LiCl, CaCl2) on surface iridescence in cooked pork was investigated. Strongest iridescence occurred in samples treated with NaSCN, NaCl and KCl. Control samples and LiCl, CaCl2 and Na2SO4 treatments showed weaker iridescence. However, differences between KCl and LiCl, CaCl2 and Na2SO4 were not statistically significant (p > 0.05). Nevertheless, a tendency of chaotropic salts (NaSCN, NaCl, KCl) to cause stronger iridescence was noted that might be explained with a more effective solubilization of myofibrillar proteins (MPs), reducing incoherent scattering from the myofibrils and thus enhancing multilayer interference.


Subject(s)
Pork Meat , Red Meat , Animals , Calcium Chloride , Meat , Salts , Sodium , Sodium Chloride , Swine , Potassium Chloride/chemistry
10.
Crit Rev Food Sci Nutr ; : 1-34, 2022 Aug 25.
Article in English | MEDLINE | ID: mdl-36004604

ABSTRACT

The purpose of this review is to provide an overview of the current knowledge about proteomic and metabolic changes in beef, the microbiological alteration postmortem and during aging, and observe the influence on beef quality parameters, such as tenderness, taste and flavor. This review will also focus on the different aging types (wet- and dry-aging), the aging or postmortem time of beef and their effect on the proteome and metabolome of beef. The Ca2+ homeostasis and adenosine 5'-triphosphate breakdown are the main reactions in the pre-rigor phase. After rigor mortis, the enzymatic degradation of connective tissues and breakdown of energy metabolism dominate molecular changes in beef. Important metabolic processes leading to the formation of saccharides, nucleotides, organic acids (e.g. lactic acid), creatine and fatty acids are considered in this context as possible flavor precursors or formers of beef flavor and taste. Flavor precursors are substrates for lipid oxidation, Strecker degradation and Maillard reaction during cooking or roasting. The findings presented should serve as a basis for a better understanding of beef aging and its molecular effects and are intended to contribute to meeting the challenges of improving beef quality.

11.
Food Res Int ; 156: 111334, 2022 06.
Article in English | MEDLINE | ID: mdl-35651084

ABSTRACT

The aging of beef affects the metabolome and, thus, its quality, such as taste or tenderness. In addition to the aging method, intrinsic factors, such as breed, feed and muscle type, also have an effect on beef's metabolome. It is not known yet whether the position of the sampling in large muscles also has an influence on beef's metabolome and its aging outcome. The effect of the sampling position in M. longissimus dorsi as a large muscle was investigated in dry-aged and wet-aged beef over an aging period of 28 days. In this study, we analyzed 360 samples out of the entire length of M. longissimus dorsi of 18 'Simmental' young bulls by 1H NMR spectroscopy. The position in the muscle affected the polar fraction of metabolome of non-aged and aged beef significantly. However, sampling position did not overlay significant differences in the metabolome of dry-aged and wet-aged beef. The aging time of beef also had a significant effect on the metabolome. Marker metabolites, such as leucine, isoleucine, inosine 5'-monophosphate and hypoxanthine, were found to be indicative of the aging time applied. In addition, marker metabolites (lactic acid, anserine, O-acetyl-L-carnitine) were identified for the aging type applied.


Subject(s)
Food Handling , Meat , Animals , Cattle , Food Handling/methods , Magnetic Resonance Spectroscopy , Male , Meat/analysis , Paraspinal Muscles , Taste
12.
Foods ; 11(7)2022 Mar 23.
Article in English | MEDLINE | ID: mdl-35407004

ABSTRACT

Fibers of potato protein and polysaccharides were obtained by needleless electrospinning. Mixtures of maltodextrin DE2 (dextrose equivalent) (0.8 g/mL), DE21 (0.1 g/mL), and different concentrations of potato protein (0.05, 0.1, 0.15, and 0.2 g/mL) were used for fiber production. Glycation was performed via the Maillard reaction after thermal treatment (0/6/12/24/48 h, 65 °C, 75% relative humidity). The effects of electrospinning and heating on trypsin inhibitor activity (IA) were studied. The results of the IA assay showed that electrospinning and glycation caused significant differences in IA among blends, heating times, and the interaction of blend and heating time (p < 0.001). The higher the protein content in the fibers, the higher the IA. The lowest IA was found in the mixture with the lowest protein content after 48 h. In other blends, the minimum IAs were found between 6 and 12 h of heating. The determination of the free lysine groups showed a nonsignificant decrease after heating. However, higher free lysine groups per protein (6.3−9.5 g/100 g) were found in unheated fibers than in the potato protein isolate (6.0 ± 0.5 g/100 g). The amide I and amide II regions, detected by the Fourier transform infrared spectra, showed only a slight shift after heating.

13.
J Food Sci ; 87(4): 1731-1741, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35257380

ABSTRACT

The increasing use of wet texturized plant proteins as meat substitutes requires a characterization of their functional properties, especially in terms of pH-behavior when being mixed with meat proteins to create so-called hybrid products. In this study, a minced model system containing pork meat, curing salt, and various amounts (0-100 wt%) of wet extruded proteins from pea (Pea I, II), pumpkin (Pumpkin I, II, III), and sunflower was used to evaluate the effect of mixing on pH and time-dependent pH-changes upon the addition of glucono-delta-lactone (GDL). Increasing concentrations of plant extrudates resulted in a linear increase of the initial (pH0h ), intermediate (pH6h ), and final pH48h for all samples and higher slopes at higher native pH of extrudates were found. Acidification kinetics of all samples were similar with a distinct pH-drop by 0.3 to 0.8 pH-units per wt% GDL in the first 6 h, followed by a plateau where pH remained constant. At extrudate concentrations of 5 wt% (Pea I, II, Pumpkin I, II) or 15 wt% (Pumpkin III, Sunflower), a sufficient acidification with typically used GDL-amounts ( = 1 wt%) could be achieved, while higher plant protein contents required higher GDL-concentrations in order to reach a pH value of 5.0; a common target value in dry-cured sausages. A mathematical model was proposed to correlate pH, time, acidifier, extrudate concentration, and plant protein origin, to aid in the adjustment of dry-cured hybrid meat formulations, and to describe thresholds of the feasible extrudate and acidifier concentrations. PRACTICAL APPLICATION: Despite the increasing relevance of texturized plant proteins as meat mimetics, little is known about their functional and process-related properties. This study shows that plant protein origin, the level of meat replacement, and the amount of acidifier are linked to the time-dependent pH-value on the basis of a mathematical model. This brings food developers one step closer in creating tailored formulations and estimating the effects of these novel ingredients in the final product characteristics of hybrid meats and analogues.


Subject(s)
Meat Products , Pork Meat , Red Meat , Animals , Hydrogen-Ion Concentration , Plant Proteins , Swine
14.
BMC Res Notes ; 15(1): 77, 2022 Feb 22.
Article in English | MEDLINE | ID: mdl-35193650

ABSTRACT

OBJECTIVE: The objective of this study was to investigate the effect of pH change of cooked cured pork M. longissimus thoracis et lumborum on iridescence intensity and extent (= percentage of iridescent area) since interaction with light may be related to pH-induced alterations in microstructure. Muscles were injected with brines of different pH values, cooked, sliced perpendicular to muscle fiber direction, and visually evaluated by a panel of 20 experienced panelists. RESULTS: Muscles with lowest pH (5.38) showed the lowest iridescence score of 4.63 (p < 0.05). Iridescence was greatest in muscles with normal (5.78) and high pH (6.03, respectively 6.59), but did not differ significantly (p > 0.05). Iridescence was positively correlated (p < 0.01) with pH and water content, and negatively correlated (p < 0.01) with cooking loss. Hence, hydration state and light scattering from microstructure may be important factors that determine the degree of iridescence in cooked meat products.


Subject(s)
Pork Meat , Red Meat , Animals , Color , Cooking , Hydrogen-Ion Concentration , Iridescence , Meat , Muscle Fibers, Skeletal , Muscle, Skeletal , Swine
15.
Food Funct ; 13(2): 944-956, 2022 Jan 24.
Article in English | MEDLINE | ID: mdl-35005757

ABSTRACT

The exchange of animal-based for plant-based proteins is becoming more and more popular due to an increasing demand for alternative and more sustainable protein sources. In this study, solubilized water- (ws) or salt-and-water (sws) meat proteins were evaluated in their pH-dependent interactions with soluble protein fractions from wheat, pumpkin, sunflower, rapeseed, or potato proteins. For this purpose, 1 : 1 (v/v) mixtures of 1.0 wt% meat (ws or sws) and plant proteins were prepared at a sodium chloride concentration of 1.8 wt% (ionic strength: 0.31 mol L-1) and adjusted to different pH-values in between 4.5-7.0. While only slight differences were found upon comparison of interactions of ws and sws batches (p > 0.05), interactions among these animal-based and soluble plant proteins took place. First, optical observations, light microscopy, and SDS-PAGE revealed increasing protein solubility with increasing pH. Second, particle size distributions (PSDs) revealed a shift towards slightly larger particle sizes e.g. at pH 5.3 and 7.0 with d4,3 of 43.2 and 21.3 µm (sws) to 45.4 and 23.9 µm (sws + potato), respectively. Furthermore, heat-induced gel formation was improved at pH > 6.0, in particular in mixtures of meat and wheat or rapeseed proteins that formed a homogenous gel structure. Based on the obtained results, protein-protein complexations mainly by electrostatic forces are suggested which occur due to various pI of meat and plant proteins e.g. pH 7.5 (wheat), 7.2 (potato), and 6.6 (rapeseed) in comparison to 5.1 (ws) and 5.6 (sws). The filamentous microstructure of some gels (soluble fraction of rapeseed, potato and wheat proteins) led to the assumption that meat proteins, mainly at pH values greater than 5.8 (optimally ≥6.5), had a structuring effect on plant proteins.


Subject(s)
Food Handling/methods , Meat Proteins/chemistry , Plant Proteins/chemistry , Animals , Electrophoresis, Polyacrylamide Gel , Hydrogen-Ion Concentration , Meat/analysis , Microscopy, Electron, Scanning , Swine
16.
J Sci Food Agric ; 102(3): 1021-1029, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34312871

ABSTRACT

BACKGROUND: The use of plant proteins as food ingredients might be limited due to the presence of foreign or 'off' flavors, which may evolve during extraction and subsequent processing. In this study, the influence of dry (TVP) and wet (WTP) texturization on characteristic volatile compounds of two different pea protein isolates was assessed using gas chromatography-mass spectrometry-olfactometry (GC-MS-O) after direct immersion stir bar sorptive extraction (DI-SBSE). RESULTS: Twenty-four odor-active compounds were found, with a prevalence of carbonyls from fat oxidation. Nine of these compounds which are also known as major (off-) flavor contributors in peas were distinctively impacted in all texturates: hexanal, nonanal, 2-undecanone, (E)-2-octenal, (E, Z)-3,5-octadiene-2-one, (E, E)-2,4-decadienal, 2-pentyl-furan, 2-pentyl-pyridine, and γ-nonalactone. For example, hexanal, a characteristic green odorant, was reduced by up to sixfold by wet texturization, from 3.29 ± 1.05% (Pea Protein I) to 0.52 ± 0.02% (Pea WTP I). Furthermore, (E,Z)-3,5-Octadiene-2-one and (E,E)-2,4-decadienal were decreased by 1.5- and 1.8-fold when Pea Protein I and Pea TVP I were compared. CONCLUSION: An overall reduction in fat oxidation products and of green and fatty odor-active compounds was observed. The results represent a first insight into the process-related modulation of pea protein (off-) flavors to broaden the applicability of pea proteins as food ingredients.


Subject(s)
Odorants/analysis , Pea Proteins/chemistry , Pea Proteins/isolation & purification , Pisum sativum/chemistry , Solid Phase Extraction/methods , Volatile Organic Compounds/chemistry , Volatile Organic Compounds/isolation & purification , Fats/chemistry , Flavoring Agents/chemistry , Flavoring Agents/isolation & purification , Gas Chromatography-Mass Spectrometry , Oxidation-Reduction
17.
Food Res Int ; 150(Pt B): 110803, 2021 12.
Article in English | MEDLINE | ID: mdl-34863495

ABSTRACT

There is an increasing demand to develop and characterize high moisture extrudates from alternative plant proteins due to their increased use in various foods. In this study, wet texturized proteins from two pea isolates and four oilseed flours from pumpkin and sunflower were subjected to an acid titration to gain insights into their buffering capacity. Results were compared to pork meat with a special emphasis on compositional differences. Wet texturized pumpkin and sunflower proteins had the highest buffering capacity, especially in between pH7.0 and pH4.5, while pea protein extrudates and pork meat were more prone to acidification and similar in buffering capacity. A multiple linear regression model further revealed that ash and select minerals and amino acids are key influencing factors on the overall buffering capacity, while the effect of protein and non-protein nitrogen depends on the evaluated pH-regime. The obtained results underline the importance for a more in-depth physicochemical characterization of texturized plant proteins and their raw materials and suggest a need for recipe and process adjustment to achieve stable pH values.


Subject(s)
Pork Meat , Red Meat , Animals , Chemical Phenomena , Flour , Plant Proteins , Swine
18.
J Food Sci ; 86(8): 3563-3573, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34268771

ABSTRACT

Microstructural factors associated with surface iridescence in cooked, cured pork products were investigated. Meat iridescence is a commonly observed physical phenomenon in raw meat and meat products that consist of intact muscle tissue. Since the purchase decision of consumers is mainly driven by the first impression of meat color and appearance, products showing colorful iridescence may be rejected. Four different muscles (RF: M. rectus femoris, BF: M. biceps femoris, ST: M. semitendinosus, and LD: M. longissimus thoracis et lumborum) were brine-injected, cooked, sliced, and iridescence was evaluated by digital image analysis and sensory analysis. Sarcomere lengths, fiber diameters, and surface microstructure were analyzed in iridescent and noniridescent sections. Highest iridescence extent by image analysis was found in LD (37.3 ± 16.4%), and highest overall iridescence score (extent and intensity, 6.11 ± 1.78) was observed in BF. Sarcomere lengths did not differ significantly between iridescent (1.05 ± 0.09 µm LD) and noniridescent areas (1.08 ± 0.94 µm LD) within muscles (p > 0.05). Iridescent sections showed smooth and ordered surface structures with cross-sectioned myofibers, whereas in noniridescent sections, surfaces were more unstructured and myofibers obliquely cut. The results of the study indicate that the sarcomere length and fiber diameters may thus be only of minor importance for the explanation of meat iridescence in cooked meat products and are rather related to multiple scattering and absorption effects on smaller structural entities such as the myofilament lattice or larger entities such as fiber bundles. PRACTICAL APPLICATION: Iridescence can be a problem for the meat industry due to consumers concerns about green-iridescent colors in meat. The underlying mechanisms and structures have not yet been fully clarified, and thus no practical solutions to eliminate iridescence have been found so far. This research presents new insights into the structural attributes that are interrelated with meat iridescence and shows that iridescence is rather influenced by cutting angle of muscle fibers and surface homogeneity than by muscle fiber diameters or sarcomere lengths. This should be considered by the industry when seeking for ways to reduce the potential problem of iridescence.


Subject(s)
Meat Products , Pork Meat , Red Meat , Animals , Humans , Iridescence , Meat , Muscle, Skeletal , Sarcomeres , Swine
19.
Food Res Int ; 145: 110416, 2021 07.
Article in English | MEDLINE | ID: mdl-34112419

ABSTRACT

Recently an approach has been developed to structure plant-based lipids with the intention to mimic animal fat tissue in processed meat products or analogues. This study investigated the comminution behavior in a bowl chopper of such structured lipids with varying mechanical properties. For products like salami-type sausages these systems need to withstand comminution to yield particles for inclusion in product matrices. Therefore, samples were prepared from protein suspensions with 6%, 8%, 10%, and 12% soy protein isolate (SPI) and 70% (w/w) total fat with varying solid fat contents (0-30%, w/w). The hardness of samples prepared with 6% and 8% SPI varied between 4.5 and 35.9 N. When comminuted in a bowl chopper, these structures had insufficient mechanical strengths to facilitate the formation of small particles and yielded a coarse paste. Higher concentrations of protein increased hardness (15.9-76.2 N and 15.6-96.1 N, for 10% and 12% SPI, respectively). These samples retained their structural integrity upon comminution yielding individual intact particles. The size of these particles increased with sample firmness, i.e. with increasing amount of protein. The shape of the particles was more elongated the higher the solid fat content as indicated by a higher aspect ratio. Taken together, results show that structural characteristics of the gelled emulsions can be tuned to yield desired fat particles after comminution.


Subject(s)
Food Handling , Meat Products , Animals , Emulsions , Lipids , Meat Products/analysis , Soybean Proteins
20.
J Sci Food Agric ; 101(13): 5707-5714, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33788286

ABSTRACT

BACKGROUND: In the presence of ascorbic acid, the degradation of acylated (sinapic, ferulic and p-coumaric acid derivatives of cyanidin-3-xylosylglucosylgalactoside) and non-acylated anthocyanins of black carrot extract (BCE) encapsulated in liposomes was studied. BCEs (0.2% and 0.4% w/w) were encapsulated in liposomes using different lecithin concentrations (1%, 2% and 4% w/w). RESULTS: The liposomes were prepared with particle diameters of less than 50 nm and zeta potentials of about -21.3 mV for extract-containing liposomes and -27.7 mV for control liposomes. The encapsulation efficiency determined using high-performance liquid chromatography (HPLC) showed that increasing lecithin levels increased the efficiency to 59% at the same extract concentration. The concentrations of total anthocyanins and individual anthocyanins were determined for ascorbic acid (0.1% w/w)-degraded extract and liposomes (containing 0.2% w/w extract). Anthocyanin quantification of both liposomal and extract samples was performed by HPLC using cyanidin-3-O-glucoside chloride as standard. Five anthocyanins in the extract and encapsulated liposomes were quantified during 24 h (0-24 h): cyanidin-3-xylosylglucosylgalactoside 1.0-0.51 and 0.82-0.58 mg g-1 , cyanidin-3-xylosylgalactoside 2.5-1.1 and 2.2-1.7 mg g-1 , cyanidin-3-xylosyl(sinapoylglucosyl)galactoside 0.51-0.14 and 0.35-0.28 mg g-1 , cyanidin-3-xylosyl(feruloylglucosyl)galactoside 1.37-0.41 and 1.06-0.98 mg g-1 , and cyanidin-3-xylosyl(coumaroylglucosyl)galactoside 0.28-0.08 mg g-1 for extract and 0.27-0.26 mg g-1 for liposomes, respectively. CONCLUSIONS: This study demonstrates the potential beneficial effect of liposomal encapsulation on individual, particularly acylated, anthocyanins after addition of ascorbic acid during a storage time of 24 h.


Subject(s)
Ascorbic Acid/chemistry , Daucus carota/chemistry , Drug Compounding/methods , Liposomes/chemistry , Plant Extracts/chemistry , Acylation , Plant Roots/chemistry
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