Instrumental and Sensory Texture Attributes of High-Protein Nutrition Bars Formulated with Extruded Milk Protein Concentrate

Development of Protein Rich Pregelatinized Whole Grain Cereal Bar Enriched With Nontraditional Ingredient: Nutritional, Phytochemical, Textural, and Sensory Characterization

This study was aimed to use extrusion cooking as a pretreatment for non-conventional seeds (Indian horse chestnut flour) to blend them with whole grain flours (whole wheat flour, whole barley flour, and whole corn flour) for the development of a pregelatinized cereal bar (PCB). In this study, date paste (7.5-17.5%) and walnut grits (2.5-12.5%) were incorporated at varying levels to prepare PCB. The PCB was evaluated for its nutritional, color, textural (both three-point bending test and TPA), antioxidant activity, and sensory attributes. The flexural modulus, rupture stress, and fracture strain of PCB increased with the incorporation of a higher proportion of date paste. The protein and fiber content in PCB increased from 7.74 to 9.13% and 4.81 to 5.59% with the incorporation of walnut grits and date paste, respectively. The DPPH, total phenolic content, and water activity of PCB were determined, which progressively enhanced with increased levels of walnut grits and date paste. The correlation between sensory attributes and instrumental texture on PCB was also investigated. The correlation results showed a significant (p < 0.05) positive correlation between texture analysis and sensory hardness, springiness, adhesiveness, and negatively correlated to instrumental and sensory cohesiveness. For sensorial attributes, all PCB samples presented average scores of 7/10 and 4/5 for buying intention. Therefore, whole grain extrudates, date paste, and walnut grits can be efficiently used to develop PCB with improved nutritional, nutraceutical, and economic values.

Physicochemical, Nutritional, Microstructural, Surface and Sensory Properties of a Model High-Protein Bars Intended for Athletes Depending on the Type of Protein and Syrup Used

The main objective of this study was to investigate the possibility of using a combination of vegetable proteins from soybean (SOY), rice (RPC), and pea (PEA) with liquid syrups: tapioca fiber (TF), oligofructose (OF), and maltitol (ML) in the application of high-protein bars to determine the ability of these ingredients to modify the textural, physicochemical, nutritional, surface properties, microstructure, sensory parameters, and technological suitability. Ten variants of the samples were made, including the control sample made of whey protein concentrate (WPC) in combination with glucose syrup (GS). All combinations used had a positive effect on the hardness reduction of the bars after the storage period. Microstructure and the contact angle showed a large influence on the proteins and syrups used on the features of the manufactured products, primarily on the increased hydrophobicity of the surface of samples made of RPC + ML, SOY + OF, and RPC + TF. The combination of proteins and syrups used significantly reduced the sugar content of the product. Water activity (<0.7), dynamic viscosity (<27 mPas∙g/cm3), and sensory analysis (the highest final ratings) showed that bars made of RPC + OF, SOY + OF, and SOY + ML are characterized by a high potential for use in this type of products.

The Influence of the Syrup Type on Rheology, Color Differences, Water Activity, and Nutritional and Sensory Aspects of High-Protein Bars for Sportsmen

Most often, high-protein bars consist of a protein preparation in the form of a loose powder, stuck together with a syrup mixture, ensuring a stable mass. According to the legal regulations in force, at least 20% of the energy value must come from protein for the product to be called high-protein. The objective of this study was to evaluate the impact of different syrup sources (oligofructose, maltitol, tapioca fiber, and chickpea-maize fiber) on rheology, water activity, color, and nutritional and sensorial properties of high-protein bars. Texture has changed depending on the type of syrup used. A significant increase of the hardness parameter referring to the control sample was noted for bars containing chickpea-maize liquid fiber in chocolate (311.65 N), with low adhesiveness simultaneously (54.71 N). Samples without chocolate made with the use of oligofructose syrup had apparently higher dynamic viscosities than other bars (226.67 mPas · g/cm3). The water activity of all tested bars indicated the high stability of samples over time (<0.80), except for samples without chocolate made of PM syrup. The color of the tested bars was from light cream to Earth yellow. Bars obtained with tapioca liquid fiber had the lowest nutritional value. Results presented in this study suggest that selecting the correct type of syrup may significantly influence the functional properties of high-protein bars.

Improving rehydration properties of spray-dried milk protein isolates by supplementing soluble caseins

Spray-dried milk protein isolates (MPIs) are important dairy ingredients but may not have desirable rehydration properties for industrial applications. In the present study, rehydration properties of MPIs were improved by spray-drying MPI dispersions containing different amounts of soluble caseins in the form of derivatized MPI (dMPI). dMPI was prepared by alkalizing MPI dispersions to pH 11.0 and subsequently acidifying to pH 6.8 (the pH-cycle). All the spray-dried MPIs had the similar bulk density (around 0.33 g/cm^-3), composition, size distribution (1-100 µm), and SEM morphology. However, the decrease of hydrodynamic diameter, dissolution of total solids and proteins, and disruption of particles during the dynamic rehydration were accelerated as the dMPI content increased, indicating the improved rehydration properties. The improvement in rehydration properties was not due to the wettability that decreased as the dMPI:MPI mass ratio changed from 0:8 to 8:0, but resulted from the reduced cross-linking of casein micelles on powder surface and the increased surface porosity during the hydration as observed for partially hydrated samples. The present work may assist industrial applications of spray-dried MPIs.

What is cohesiveness?-A linguistic exploration of the food texture testing literature

Cohesiveness is a widely used term in the food texture literature. Authors of this literature employ divergent methodologies, and can be divided into those who assess texture through sensory evaluation and those who use instrumental techniques. Within each of these disciplines, there are some specialized uses of the word, creating discipline specific terms such as "cohesiveness of mass." The fact that many researchers attempt to (re)define cohesiveness, does suggest that the term is not universally understood. This blurring arises partly from the abstract nature of what it describes and also from ill matching measurements being used to quantify it. A widely agreed definition is that cohesiveness is "the strength of the internal bonds making up the body of the product," yet a challenge continues to be how we can measure it. Using the Sketch Engine corpus analysis interface to examine a corpus of articles from the food texture literature in the periods 2002-2017, the contexts in which the word stem "cohes*" is used were explored. Collocation analysis suggests that in addition to considerable commonality in the way that "cohesiveness" combines with other terms, differences reflect the foci of the disciplines with the instrumental community predominantly dealing with physical measurement while the sensory community relate "cohesiveness" more to oral processing and texture perception.

The Effect of Protein Source on the Physicochemical, Nutritional Properties and Microstructure of High-Protein Bars Intended for Physically Active People

The purpose of this study was to investigate the effect of protein sources (algae, pumpkin, wheat, sunflower, rice, soy, hemp, pea, and whey) on selected physicochemical, nutritional, and structural parameters of high-protein bars. Texture properties, such as hardness, fracturability, cohesiveness, and adhesiveness, have changed depending on the type of protein used. A significant increase, in particular the hardness parameter relating to the control sample (whey protein concentrate-WPC80), was noted for bars containing algae, sunflower, and wheat proteins, with high values of the adhesiveness parameter concurrently. The use of proteins from algae, pea, and wheat resulted in a significant reduction in the water activity of the finished product compared to WPC80. Bars made with the use of wheat, hemp and pumpkin proteins had noticeably higher viscosities than other samples. Color of the tested bars measured by means of Computer Vision System (CVS) was from light cream (soy, pea) to dark green (hemp, pumpkin). Bars prepared of wheat and algae proteins had the highest nutritional value, while the lowest one was recorded in products containing sunflower and hemp proteins. There was a clear differentiation of amino acids (g/100 g) and microstructure in bars depending on the type of protein used. However, a slight similarity can be found between whey and soy proteins (amino acids) and between whey and sunflower proteins (microstructure). Obtained results suggest that selection of the right type of protein for a given application may have a significant impact on the physicochemical features and microstructure of high-protein bars and their nutritional values.

Pearl millet protein bar: nutritional, organoleptic, textural characterization, and in-vitro protein and starch digestibility

Pearl millet, a nutritionally remarkable cereal with a sustainable yield in the grey regions of India, is not consumed much. Consumption of Nutrition bars has gained momentum in recent years and considering this, in the present study pearl millet-based protein bars are formulated to increase its consumption rate and establish it as a reliable source of protein and other nutrients. The proximate and mineral composition of the three variants of pearl millet incorporated (25, 27.5, 30%) protein bars were analyzed using standard protocols. The acceptability of the bars was assessed using the 9-point hedonic scale among twenty panelists. The textural parameters were measured by Perten TVT 6700 Texture Analyzer. The in-vitro digestibility of protein (IVPD) and starch (IVSD) of the best variant was also estimated. The bars provide 15.74-18.32 g of protein, 332-379 kcal energy, 74.53-83.87 mg calcium, and 555.93-603.80 mg phosphorous per 100 g. The results showed that the organoleptic parameters of the bars were not affected by the proportion of ingredients. Whereas the increase in pearl millet incorporation marginally increased textural properties such as hardness, cohesiveness, and chewiness. The IVPD of the selected variant is 75.65 ± 0.02% and IVSD revealed 252.00 ± 10.00 mg of maltose is released per 100 g of the sample. The protein bars are nutritionally beneficial and appealing. This study gives scope for the production of pearl millet-based convenience foods that will raise the consumption pattern of pearl millet at the household level.

Extrusion modifies some physicochemical properties of milk protein concentrate for improved performance in high-protein nutrition bars

BACKGROUND

Extruded and ground milk protein concentrate powders, specifically those with 800 g kg^-1 protein (i.e. MPC80), imparted softness, cohesion and textural stability to high-protein nutrition (HPN) bars. The present study evaluated some physicochemical properties of extruded and conventionally produced (i.e. spray-dried) MPC80 to explain these improvements. Protein chemical changes and aggregations within MPC80-formulated HPN bars during storage were characterized.

RESULTS

Extruded MPC80 powders had broader particle size distribution (P < 0.05) and smaller volume-weighted mean diameter (P < 0.05) than the spray-dried control. Loose, tapped and particle densities increased (P < 0.05) and correspondingly occluded and interstitial air volumes decreased (P < 0.05) after extruding and milling MPC80. Extrusion decreased water holding capacity (P < 0.05) and solubility (P < 0.05), yet improved the wettability (P < 0.05) of MPC80. MPC80 free sulfhydryl (P < 0.05) and free amine (P < 0.05) concentrations decreased after extrusion. Sulfhydryl and amine concentrations changed (P < 0.05) and disulfide-linked and, more prominently, Maillard-induced aggregates developed during HPN bar storage.

CONCLUSION

Extrusion and milling together changed the physicochemical properties of MPC80. Chemical changes and protein aggregations occurred in HPN bars prepared with either type of MPC80. Thus, the physicochemical properties of the formulating powder require consideration for desired HPN bar texture and stability. © 2017 Society of Chemical Industry.

Particle Size of Milk Protein Concentrate Powder Affects the Texture of High-Protein Nutrition Bars During Storage

Milk protein concentrate powder with 85% protein (MPC85) was jet-milled to give 2 particle size distributions (that is, JM-Coarse and JM-Fine) or freeze-dried (FD), in order to improve the functional properties of MPC85 for use in high-protein nutrition (HPN) bars. Volume-weighted mean diameter decreased from 86 μm to 49, 22, and 8 μm in FD, JM-Coarse, and JM-Fine, respectively (P < 0.05). The MPC85 powders modified by jet-milling and freeze-drying were significantly denser than the control MPC85 (P < 0.05). Volume of occluded air in the modified powders decreased (P < 0.05) by an order of magnitude, yet only FD possessed a lower volume of interstitial air (P < 0.05). Particle size reduction and freeze-drying MPC85 decreased its water holding capacity and improved its dispersibility by at least 20%. Contact angle measurements showed that these modifications increased initial hydrophobicity and did not improve wettability. HPN bars made from JM-Fine or FD were firmer by 40 or 17 N, respectively, than the control on day 0 (P < 0.05). HPN bar maximum compressive force increased by 38%, 33%, and 242% after 42 d at 32 °C when formulated with JM-Fine, FD, or control MPC85, respectively. HPN bars prepared with JM-Fine were less crumbly than those formulated with control or FD MPC85. Physically altering the particle structure of MPC85 improved its ability to plasticize within HPN bars and this improved their cohesiveness and textural stability.

Effects of addition of hydrocolloids on the textural and structural properties of high-protein intermediate moisture food model systems containing sodium caseinate

High-protein intermediate moisture food (HPIMF) containing sodium caseinate (NaCN) often gave a harder texture compared with that made from whey proteins or soy proteins, due to the aggregation of protein particles.