Parameswarakumar Mallikarjunan

University of Minnesota | UMN · Department of Food Science and Nutrition

Tea (Camellia sinensis) is the most widely consumed beverage in the world, with an excellent source of bioactive compounds such as catechins, caffeine, and epigallocatechin. There is an increasing trend to extract these bioactive compounds to deliver them as value-added products. Generally, the extraction of polyphenols and other functional compoun...

Nowadays, the increasing number of foodborne disease outbreaks around the globe has aroused the wide attention of the food industry and regulators. During food production, processing, storage, and transportation, microorganisms may grow and secrete toxins as well as other harmful substances. These kinds of food contamination from microbiological an...

High pressure processing (HPP) is a well‐known technology for non‐thermal pasteurization of food materials. High pressures above 100 MPa is proven to cause microbial destruction in food. It has been employed in the treatment of meat and meat products in several commercial industries. When considering raw meat preservation, increasing the pressure b...

The study was aimed to analyse the effect of low pressure cold plasma treatment [operated at 60.8 kPa on the quality parameters of red chilli pepper powder (RCPP)]. The experiments were conducted at two radio frequency power levels (60 W, 120 W) over a time range from 0 to 10 min. Total phenols, antioxidant activity, colour, and moisture content we...

Nowadays, despite enormous scientific advances, viral diseases remain the leading cause of morbidity worldwide, and their potential to spread is escalating, eventually turning into pandemics. Nutrition can play a major role in supporting the immune system of the body and for the optimal functioning of the cells of the immune system. A healthy diet...

The aflatoxin contamination of chilli pepper grown and marketed in Tamil Nadu, a southern Indian state, was assessed. Chilli samples were collected at different stages of the value chain and were quantified using the enzyme‐linked immunosorbent assay (ELISA) test. Forty‐two representative samples were collected from four districts identified as the...

Ethnopharmacological relevance Artemisia annua L. is a traditional Chinese medicine used for the treatment of malaria, jaundice and intense fever. Aim of the study The aim of the present study was to investigate the phytochemicals, antioxidants, antimicrobial and synergistic potential of methanolic and petroleum ether extracts of A. annua against...

Black tea is considered as good source of bioactives like phenolics and antioxidants. In this study, cold brewing of black tea is coupled in combination with ultrasound‐assisted extraction (UAE) to maximize extraction efficiency of bioactives. Response surface methodology was designed to optimize the conditions for extraction using UAE for cold‐bre...

Aflatoxins are carcinogenic secondary metabolites produced by Aspergillus moulds. Chili pepper is one the economically important spices cultivated in India. Fifty percent of the chili produced in India is being exported to Europe, USA and other countries. Permissible limit of aflatoxin in red chilies has been set as 10 ppb for EU and 20 ppb for USA...

Aflatoxin in peanut ( Arachis hypogaea L.) and other crops can negatively affect human health, especially in countries where regulatory agencies do not have limits on aflatoxin entering the food supply chain. While considerable research has been conducted addressing aflatoxin contamination in peanut at individual steps in the supply chain, studies...

Increase in allergenicity towards cow's milk, lactose intolerance, the prevalence of hypercholesterolemia, and flexitarian choice of food consumption have increased the market for cow's milk alternatives. Non-dairy plant-based beverages are useful alternatives because of the presence of bioactive components with health-promoting properties, which a...

Consumers' demand is increasing for safe foods without impairing the phytochemical and sensory quality. In turn, it has increased research interest in the exploration of innovative food processing technologies. Cold plasma technology is getting popularity now days owing to its high efficacy in decontamination of microbes in fruit and fruit based pr...

Proteins represent one of the major food components that contribute to a wide range of biophysical functions and dictate the nutritional, sensorial, and shelf-life of food products. Different non-thermal processing technologies (e.g., irradiation, ultrasound, cold plasma, pulsed electric field, and high-pressure treatments) can affect the structure...

This text comprehensively covers novel, innovative technologies used in the food and beverage industries in order to provide safe and healthy foods for consumers. The research provided in these chapters aims to show that the traditional pasteurization and commercial sterilization of foods result in unacceptable quality and nutrient retention, creat...

The development and introduction of healthier products into the marketplace is an important topic of discussion. Three main knowledge areas are involved: gastronomy, food science and technology, and nutrition. The many intersections among these areas are essential since the digestion of nutrients and bioactive compounds can be influenced by thermal...

The use of Allium species and their extracts has been known since immemorial times due to their health beneficial properties. It is known that functional properties of Allium genus come from high content of bioactive compounds. The biological activity of Allium extracts will be conditioned by the type of Allium variety, agricultural conditions, and...

Spices, including black pepper and cumin seeds, have been implicated in outbreaks of salmonellosis and prompted recalls of ready-to-eat products containing contaminated spices. Vacuum-assisted steam pasteurization is performed to improve the safety and quality of many low water activity products, however process parameters associated with inactivat...

The use of high pressure processing (HPP) for development of stable emulsion-based delivery systems has been recently increased. Under adequate conditions, application of high pressures modifies the functionality of protein and polysaccharide molecules and significantly promotes the emulsifying activities. Application of high pressures also modulat...

Stevia rebaudiana Bertoni has gained increased industrial and scientific interests in the last 20 years, representing a suitable nutritional alternative to sucrose and artificial sweeteners. Moreover, this plant contains polyphenols, chlorophylls, and carotenoids that may be extracted for production of nutraceuticals and functional foods. Because o...

Ste­via re­bau­di­ana Bertoni has gained in­creased in­dus­trial and sci­en­tific in­ter­ests in the last 20 years, rep­re­sent­ing a suit­able nu­tri­tional al­ter­na­tive to su­crose and ar­ti­fi­cial sweet­en­ers. More­over, this plant con­tains polyphe­nols, chloro­phylls, and carotenoids that may be ex­tracted for pro­duc­tion of nu­traceu­ti­...

Background Consumption of protein-based food products has a key role in the improvement of human health. The crosslinking agent microbial transglutaminase (mTGase) is an effective and promising tool to modify animal proteins used in the food industry. Improvement in the gelation process, physicochemical and textural quality, and consumer's demand o...

Gamma aminobutyric acid (GABA) is a non-protein amino acid, which has received extensive attention over the past decades due to its various physiological implications in plants, animals, and microorganisms. It has anti-diabetic and hypotensive effects, depression and anxiety reduction properties, and many other health-related benefits. Recent effor...

Thermal treatment is one of the main unit operations applied to improve the microbiological quality of food products. It utilizes the lethal effects of heat against thermosensitive microorganisms and pathogens which cause food spoilage; however, at the same time it induces degradation of the organoleptic and nutritional properties of foods due to M...

Nanoemulsions are submicron sized systems utilized in the food and pharmaceutical industries for the delivery of active ingredients. Compared to other emulsion-based systems (e.g. conventional emulsions), nanoemulsions have shown to be more stable to environmental and process stresses due to their large active surface area, but are also susceptible...

The effect of high pressure (200-600 MPa), pressurization time (0-60 min) and heat treatment temperature (15-65oC) on change in pH and storage modulus (G') of the acidified milk gel in the preparation of soft cheese was studied. The value of the pH of the heat assisted high pressure (HAHP) treated samples was observed to vary from 5.48 to 5.31 afte...

Infestations by Prostephanus truncatus Horn (Coleoptera: Bostrichidae) and Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) are prevalent in small-scale Zea mays L. storage facilities in Tanzania and other regions of sub-Saharan Africa. It is especially difficult to detect these species' larvae, which feed unseen inside the grain kernels....

Aspergillus colonization on peanuts is a growing concern, as it results in reduced crop yields or livestock productivity due to consumption of contaminated feed, and most importantly, they are famous as causative agents of opportunistic infestation in man. In order to defeat and evaluate peanuts suffering from Aspergillus infection, it is essential...

This study demonstrated the potential use of Fourier transform infrared spectroscopy, coupled with attenuated total reflectance unit (FTIR-ATR) for determination of aflatoxigenic and non-aflatoxigenic strains of Aspergillus flavus and Aspergillus parasiticus invasion in peanuts. Threshold mold density on peanut paste samples was 2.7 Log CFU/g peanu...

The quality and safety of a cooked food product depends on many variables, including the cooking method and time-temperature combinations employed. The overall heating profile of the food can be useful in predicting the quality changes and microbial inactivation occurring during cooking. Mathematical modeling can be used to attain the complex heati...

The efficacy of nutraceuticals or therapeutics is primarily a function of their conserved biological activity and availability. As changing the size of fabricated materials into nanoscale, the stability and the solubility of valuable nutrients can tremendously be improved; and their effective and controlled delivery via nano-vehicles can be provide...

Postprocessing contamination of the products in a processing plant has been identified as one of the major reasons for food contamination with Listeria ; brining is one such postprocessing area. Our previous study has shown that the combinations of UV and antimicrobials reduces the number of this organism significantly in fresh brine, but brine is...

The core concepts, or threads, of biosystems engineering (BSEN) are variously understood by those within the discipline but have never been unequivocally defined due to BSEN's early stage of development. This makes communication and teaching difficult compared to other well-established engineering disciplines. Biosystems engineering is a field of e...

Chill brine used during ready-to-eat meat processing is an important source of postprocessing contamination by Listeria monocytogenes. The efficacy of UV in combination with citric acid (CA; 0.2 and 0.5%), dimethyl dicarbonate (DMDC; 250 and 500 ppm) or hydrogen peroxide (2,000 and 4,000 ppm) was determined to reduce L. monocytogenes in chill brine...

The ability of two electronic nose systems (conducting polymer and surface acoustic wave-based) to differentiate volatiles of grapes and wines treated with an aqueous ethanol spray (5% v/v) at veraison was evaluated. Ethanol spray induced fruit ethylene production immediately posttreatment, which then declined progressively. The electronic nose eva...

A large number of compounds have been reported in peanut plants. Many of these compounds are phytoalexins, which are produced by plants experiencing environmental stress and often exhibit antioxidant activity. It is difficult to determine which of the many compounds has the greatest impact on total antioxidant capacity in a mixture. The objectives...

The effect of grapevine canopy side (north versus south and east versus west) on grape and wine volatiles of Cabernet franc was evaluated during two growing seasons using two electronic nose systems based on conducting polymers and surface acoustic waves. Data from three sampling dates per season from both electronic noses were compared with physic...

A microwave-assisted extraction system was used to extract phenolic antioxidants from peanut skins. The effects of microwave power (10%, 50%, 90% nominal), irradiation time (30, 90, 150 s) and sample mass (1.5, 2.5, 3.5 g) on total phenolic content (TPC), ORAC (oxygen radical absorbance capacity) level and resveratrol content of peanut skin extract...

Cold soak is a prefermentation maceration process at cold temperatures, traditionally used to enhance red wine color. This study monitored changes in Vitis vinifera L. cv. Cabernet Sauvignon volatiles using a commercial conducting polymer electronic nose (ENose) during a five-day cold soak and postfermentation. Principal component analysis (PCA) of...

In 2004, a group of engineering and education faculty at Virginia Tech received a major curriculum reform and engineering education research grant under the department-level reform (DLR) program of the NSF. This DLR project laid the foundation of sponsored research in engineering education in the Department of Engineering Education. The DLR investi...

Despite the hype about healthy, low-carb/low-fat diets, the production of deep-fat fried foods continues to be a major processing operation around the world, generating billions of dollars each year. Due to their uniquely crispy exterior and juicy interior, breaded fried foods, in particular, are popular among consumers. Unlike many books that have...

Interaction of taste molecules with saliva is the first step in the flavor perception process. Saliva is assumed to influence copper-induced sensation by controlling the copper solubility or causing astringency via binding of proteins with copper. This study was performed to identify the nature of copper-protein interactions in relation to the sens...

Peanut skins are a byproduct of peanut blanching operations and contain high levels of phenolic antioxidants. The effect of solvent type (methanol MeOH, ethanol EtOH, and water), concentration (0, 30, 60, 90%), temperature (30, 45, 60 degrees C), and time (10, 20, 30 min) on total phenolic content (TPC), oxygen radical absorbance capacity (ORAC) le...

In this study, five groups of sequentially spoiled crabmeat were evaluated by a trained sensory panel, and these results were compared with the findings from a Cyranose 320 Electronic Nose and Draeger gas analyzer. Using the electronic nose with filtered compressed breathing air yielded the best results. Although this approach resulted in 100 % sep...

Introduction Electronic Nose Niche Electronic Nose Market Types of Chemosensory Systems Statistical Analysis Applications in the Food Industry References

The effectiveness of two electronic nose (e-nose) systems to assess the quality of oysters was studied on live oysters stored at 4 and 7°C for 14 days. E-nose data were correlated with a trained sensory panel evaluation by quantitative description analysis and with aerobic plate count. Oysters stored at both temperatures exhibited varying degrees o...

The ability of an electronic nose to classify cabernet sauvignon (Vitis vinifera L.) fruit based on maturity levels was investigated over two seasons. Maturity of samples collected 18, 19, and 20 weeks post-bloom was evaluated by measuring berry weight, pH, Brix, titratable acidity, total phenols, color intensity, hue, total anthocyanins, and total...

Wine discrimination and analysis is typically done through chemical analysis and sensory evaluation by a trained panel. Both of these methods are proven to be successful in wine discrimination, but require extensive preparation, time and money. The electronic nose is an objective, rapid-analysis tool that has been used in the food industry for a nu...

One of the ABET criteria specifically requires students to be able to work in a professional and ethical manner upon graduation. Incorporating ethical thinking into student learning has often been considered a challenge in engineering curriculums. The Biological Systems Engineering (BSE) and Engineering Education (EngE) departments at Virginia Tech...

The Engineering Education and Biological Systems Engineering departments at Virginia Tech have identified a need for a spiral themed curriculum in undergraduate engineering education. Approval for carrying out studies in implementing the spiral curriculum was approved in the Biological Systems Engineering (BSE) department in November 2007 by the un...

Forty untrained human subjects were used to determine if sensory differences exist between breaded chicken nuggets fried using three treatment combinations: (i) nuggets coated with 3% methylcellulose incorporated into the predust and fried using nitrogen gas; (ii) uncoated nuggets fried using steam, and (iii) uncoated nuggets fried using nitrogen g...

The recent trend in reducing the fat content in fried foods is leading to the development of low-fat products using batter and breading formulations from protein and other hydrocolloids. The functionality of many of these edible ingredients on moisture retention and fat barrier properties during deep-fat frying is not clearly understood. The object...

A mathematical model for microwave cooking of cocktail shrimp was developed. the model included heat and mass transfer and microbial inactivation kinetics. A simple 2 dimensional cylindrical slab geometry was used and model equations were solved using the finite difference method. the model predictions on temperature and mass loss were in good agre...

Dielectric properties of shrimp (Penaeus sp.) were measured at frequencies between 0.3 and 3 GHz from -25 to 70C by using a network analyzer. The relationship between dielectric properties and temperature was determined at 915 MHz and 2450 MHz. Below the freezing point, the dielectric constant (ɛ′) and dielectric loss factor (ɛ″) increased rapidly...

Predictive equations to compute the chilling time, mass loss at the end of chilling, temperature history at the geometric center of round and mass loss history during beef carcass chilling were developed using validated computer models and response surface analysis. Central composite rotatable design was used to obtain quadratic response surfaces f...

To enhance ethics training during the undergraduate career, engineering ethics material should be presented throughout the engineering curriculum. In continuation of the Department Level Reform (DLR) project, funded by the National Science Foundation (NSF), two departments at Virginia Tech aim to implement ethics throughout a four-year program by u...

Currently, random and destructive sampling techniques are used to evaluate apple quality. Thus there is need to develop a non-destructive technique to assess apple quality. Maturity indices such as starch index and puncture strength were used to categorize Gala apples into three maturity groups referred to as immature, mature and over mature fruits...

Kinetic models for changes in muscle pH and beef quality, based on press juice and puncture strength, were determined during beef carcass chilling. Changes in quality of Longissimus dorsi muscle during chilling were determined and modeled using reaction kinetics and Eyring's absolute reaction rate theory. The pH and press juice followed first order...

The effects of 2 edible coatings, methylcellulose (MC) and whey protein isolate (WPI), and 2 pressure sources (nitrogen gas and steam) on the quality attributes (crispness, moisture and fat content, juiciness, color, and texture) of breaded fried chicken nuggets were evaluated. MC or WPI was incorporated into either the pre-dust or the batter befor...

Flavor characteristics of roasted peanuts over short-term storage were explored through sensory and chemical analyses. The volatiles from freshly roasted peanuts were evaluated over short-time (21 d) storage using gas chromatography, chemosensory techniques, and a sensory panel to quantify and identify pyrazines and hexanal over a 21-d storage peri...

The potential for using nitrogen gas as a pressurizing medium in a deep-fat fryer was investigated. Effects of different frying temperatures (150, 175 and 190C) and pressures (101, 163 and 184 kPa) on the fried food quality were studied. Chicken nuggets were either fried for a constant frying time of 240 s or at a constant core temperature of 70C i...