Food Technology
Parisa Shahiri Tabrestani; Mahboobeh Kashiri; Yahya Maghsoudlou; Hoda Shahiri Tabarestani; Mohammad Ghorbani
Abstract
Introduction
There ...
Read More
Introduction
There has been an increasing demand for functional analog meat products due to environmental, human health, and animal welfare concerns. Burger analogs are plant-based products that are designed to mimic the taste, texture, and appearance of meat burgers. They are typically made from a combination of plant-based ingredients such as textured vegetable protein, legumes, grains, and vegetables. The goal of burger analogs is to provide a meat-like experience without using animal-based products.These formulations aim to provide a healthier and sustainable alternative to conventional meat products. The organoleptic properties of burger analogs, including texture, taste, and aroma, are crucial for their acceptance by consumers.
Prickly pear (Opuntia stricta) is a fruit from the Cactaceae family that contains various beneficial components, including natural pigments, proteins, fibers, and polysaccharides. Pectic polysaccharides and arabinogalactans are two types of polysaccharides found in prickly pear that have thickening properties and can improve the texture of food products. Moreover, Prickly pear is a nutritious and functional fruit that can provide various benefits when incorporated into the diet or used as an ingredient in food products. To date, no health benefit analog burgers incorporating Opuntia fruit have been developed.This study investigated the effects of adding Prickly pear pulp powder at levels of 0.5-2.5% on the physicochemical, sensory, and textural properties of analog burgers.
Materials and Methods
Analog burgers were formulated according to Iranian national standards using common ingredients (texturized soy protein, water, canola oil, garlic, dehydrated onion, soy sauce, and guar gum) as a control sample. Mature prickly pear fruits (Opuntia stricta) were collected from west of Mazandaran province in February. The fruits were washed, peeled, and dried in a forced oven dryer at a temperature of 45 °C. The dried samples were then ground into a powder and stored at 4 °C until further physico-chemical parameters of the including moisture, pH, ash, protein, lipid, color and total phenolic content. For developing new formulation of analog burgers, the roasted flour was substituted with prickly pear pulp powder at 0.5%, 1.5%, and 2.5% of the base recipe. The average moisture, ash, fat, carbohydrate content, pH, holding capacity, and color of each raw packed burger were measured. The hardness, springiness, cohesiveness, and chewiness of cooked analog burgers were evaluated using a texturometer instrument. Sensory analysis was performed by 10 panelists who judged discrimination scales of color, odor, taste, and texture characteristics. Analysis and sample treatments were repeated at least three times. Statistical analysis was performed using SPSS (version 19.0), and data were expressed as means ± standard deviation (SD).
Results and Discussion
The lowest and highest cooking losses were observed in analog burgers with 2.5% pulp powder (21.03 ±0.47%) and the control (22.2 ± 0.63%), respectively. However, moisture retention and juiciness did not show significant differences (p > 0.05) between analog burgers with prickly pear pulp powder and the control. The results indicated that increasing prickly pear pulp powder levels significantly decreased the redness (+a*) parameter and yellowness (+b*) of raw analog burgers. Moreover, a reduction in cooking loss and shrinkage were observed for cooked soy burger samples using prickly pear pulp powder. However, cooked analog burgers with added prickly pear pulp powder showed significantly higher juiciness. The elasticity of the produced analog burgers significantly decreased with an increasing percentage of pulp powder (p <0.05).
Conclusion
The incorporation of prickly pear pulp powder in analog burger formulation resulted in a significant decrease in cooking loss and shrinkage of the cooked burgers, while not significantly affecting moisture retention and juiciness. An increase in prickly pear pulp powder levels in analog burger formulation led to a significant decrease in the redness and yellowness of the raw analog burgers, as well as a decrease in their elasticity. Based on the sensory evaluation and consumers' overall tendency to consume burgers, it is recommended to use 1.5% prickly pear pulp powder in analog burger formulation.
Food Chemistry
Maryam Rahimipanah; Alireza Sadeghi Mahoonak; Mohammad Ghorbani; Hoda Shahiri Tabarestani; Mohsen Nabimeybodi
Abstract
Introduction
High levels of free radicals can damage biomolecules and eventually cause oxidative stress. Bioactive peptides produced during enzymatic hydrolysis keep high health properties, such as antioxidant properties. The production of antioxidant peptides has received much attention as a ...
Read More
Introduction
High levels of free radicals can damage biomolecules and eventually cause oxidative stress. Bioactive peptides produced during enzymatic hydrolysis keep high health properties, such as antioxidant properties. The production of antioxidant peptides has received much attention as a new generation of natural antioxidants. Plants are one of the most abundant sources of biopolymers, especially protein. As long as the protein structure is intact, its amino acid sequence is inactive; however, during proteolysis, fermentation, and gastrointestinal digestion, these amino acids are released as oligopeptides ordinally with less than 20 amino acids and below 10 kDa in molecular weight. These peptides are more digestible and can exhibit specific bioactive properties such antioxidant properties. In this regard, the use of food waste containing protein to produce bioactive peptides and increase their value has received increasing attention. Enzymatic hydrolysis can increase their functional properties by converting proteins into peptides without affecting their nutritional value. Pomegranate seed protein is a by-product of the pomegranate seed oil industry and can be a good source of bioactive peptides with antioxidant properties. According to our knowledge, there isn’t any data about the enzymatic hydrolysis of pomegranate seed protein for antioxidant peptides production. In this study, the optimal conditions for enzymatic hydrolysis of pomegranate seed protein with trypsin using the responses surface method and the effect of hydrolysis on protein structure were investigated.
Materials and Methods
In this study, the protein was extracted from pomegranate seed, and using trypsin the optimization of enzymatic hydrolysis conditions of protein was determined by Face-Centered Central Composite design, which is one of the responses surface design methods. The effect of independent variables including temperature (30 to 45 °C), time (30 to 180 minutes), and enzyme to substrate ratio (1 to 3 w/w) on DPPH free radical scavenging activity and Fe+3 reducing power as responses, was evaluated. Validation tests were performed for confirmation of the proposed values by software and the degree of hydrolysis of the samples was determined. In the next step, the unhydrolyzed and hydrolyzed protein was evaluated for molecular weight distribution and their surface hydrophobicity was compared. Finally, scanning electron microscopy images were used to confirm the hydrolysis process.
Results and Discussion
Under optimal conditions obtained from the response surface method (temperature: 37.6 °C, time: 136.55 minutes, and enzyme to substrate ratio: 2.2%), trypsin-derived hydrolyzate, showed DPPH free radical scavenging power: 87±0.89% and Fe+3 reduction power: 0.293±0.44. Under these conditions, the degree of hydrolysis was equal to 30.1±1%. The optimum conditions of hydrolysis were validated by RSM. The increase in the surface hydrophobicity of the protein after the hydrolysis process indicated the unfolding of the pomegranate seed protein chain and the exposure of its structure during the reaction. The electrophoretic profile of denatured pomegranate seed protein showed smaller peptide bands and lower band intensity, along with losing some of the peptide fractions after hydrolysis. so the efficacy of trypsin at cleaving the protein was confirmed. Evaluation of images obtained by scanning electron microscopy showed that unhydrolyzed protein had complex structures comprised of random sheets of different sizes and shapes and the protein degraded into small fragments and looser structure with many folds after enzyme hydrolysis, resulting in smaller particles compared with untreated samples with the same SEM parameters
Conclusion
Considering the consumer’s tendency toward functional foods and present concerns about the application of synthetic additives and according to the results, the hydrolyzed pomegranate seed protein prepared by trypsin shows good antioxidant capacity. In addition, there will be a reduction in waste generated by the pomegranate processing industry. Further studies will need for the isolation and identification of the specific peptides and amino acid sequences and the evaluation of their possible incorporation in food matrices.