An effect of fat emulsions of black soldier fly (Hermetia illucens) larvae on the germination capacity and energy of sprouting of pea (Pisum sativum L.) seeds

Various oils, fats and emulsifiers in the composition of preparations for soil enrichment or plant protection can have a significant effect on the germination capacity and energy of sprouting of pea seeds. Fat of black soldier fly (Hermetia illucens) larvae can be used as a pesticide carrier as well as for increasing seed resistance to contamination with fungi and insects during storage and sprouting. Therefore, the aim of the study was to determine an effect of insect fat in a form of an emulsion on sprouting of pea seeds of the variety “Rodnik” depending on a type of an emulsifier or stabilizer. It was found that the use of 0.3 weight% of xanthan gum as a stabilizer for fat emulsion of black soldier fly (Hermetia illucens) larvae significantly increased the number of germinated seeds and the energy of seed sprouting. The use of 1–5 weight% of Tween 20 as an emulsifier for fat of black soldier fly (Hermetia illucens) larvae led to inhibition of seed growth. Lecithin, sodium caseinate and microcellulose with addition of fat of black soldier fly (Hermetia illucens) larvae also decreased the germination capacity and sprouting of pea seeds (Pisum sativum L.).

Results of the complex evaluation of bryndza cheese and the byproduct milk whey with the use of enzyme MTG and its activity degree during storage

The paper examines the question of using the enzyme microbial transglutaminase (mTG) for bryndza cheese production. Microbial transglutaminase belongs to the enzyme family that catalyzes formation of bonds between amino groups. One of the problems in production of high-protein products, in particular, cheeses from goat milk is flabbiness of the clot. The use of mTG in the technological process would allow strengthening the product protein matrix, thereby improving its commercial characteristics. When performing the histological investigation of cheeses with this enzyme type to characterize the state of the protein matrix, the authors established that the product protein structure was more condensed compared to the control samples (without mTG), which affected cheese consistency. Consistency became more rubbery negatively influencing the product sensory properties, which are important traits for a consumer when buying a product. Using a Brookfield texture analyzer, it was shown that structural-mechanical characteristics were improved by 1.5 times for cheese samples produced from cow milk and by 2 times for goat cheese when mTG was used. Analysis of the enzyme catalytic activity showed that this enzyme retained its activity throughout the whole storage period, which is a potential hazard for human health. After shelf-life expiration, a change in the mTG activity was not more than 5% relative to the initial levels. The enzyme activity retained not only in cheese but also in the by-product — cheese whey, which made its processing more difficult.

Glycation end products and technological aspects of reducing immunogenicity of specialized food products for nutrition of athletes

Food allergy, which affects about 8% of children and 5% of adults in the world, is one of the major global health problems, and allergen control is an important aspect of food safety. According to the FALCPA (Food Allergen Labeling and Consumer Protection Act of 2004 FDA), more than 160 foods can cause allergic reactions, with eight of them responsible for 90% of all food allergies in the United States, including milk, eggs, wheat, peanuts, soybeans, tree nuts, crustaceans and fish, also known as the Big 8. Most foods that are sources of obligate allergens are heat treated before consumption, which can trigger the Maillard reaction, which produces glycation end products. Symptoms of food sensitization are known to significantly affect the quality of life, gut microbial diversity and adaptation potential. In particular, in athletes, this can be expressed in a decrease in the effectiveness of the training process, which leads to poor endurance and athletic performance. In this regard, it seems relevant to study the effect of the Maillard reaction and AGEs on the immunogenicity of proteins and the possible relationship between these compounds and food allergy, as well as to develop measures to prevent the adverse effect of allergens on the body of a professional athlete and any other consumer.

Establishment of metrological parameters of the method for measuring the protein mass fraction in fish food products by the Kjeldahl method

In laboratory practice, there are many protein quantification methods, and all of them have their own advantages and disadvantages. The most common and widely used method for the protein analysis in food products, including fish, is the Kjeldahl method. However, the current standards for measurement methods for the determination of the protein content in fish food products do not provide for the use of devices that meet the modern level of technical development, and also do not contain metrological indicators that guarantee the reliability of the results obtained. The aim of the study was to substantiate the method for measuring the protein mass fraction in fish food products by the Kjeldahl method on an automatic analyzer and to establish metrological parameters. The assessment of the quality indicators of the Kjeldahl measuring method was carried out using a Kjeltec System 2300 Nitrogen Analyzer (Foss Analytical AB, Sweden) in the form of a characteristic of the measurement error and its components, which will provide results with the required accuracy.

Evaluation of microbiological risks in cream as a raw material for buttermaking

The article presents the research results of studying the influence of various groups of microorganisms — coliform bacteria, lactic acid microorganisms, yeast, and spore bacteria — on the quality and storage capacity of cream used as a raw material for buttermaking. The objects of study were the following: cream as a raw material before and after pasteurization, as well as pasteurized cream seeded with testing cultures of various types of spoilage microorganisms. The samples were stored at temperature conditions of 30 ± 1 °C, 10 ± 1 °C, and 4 ± 2 °C. To evaluate the quality and storage capacity of cream used as a raw material, its microbiological and physicochemical indicators were determined by standardized methods: bacterial number, titratable acidity, indicators of oxidative spoilage of the fat phase. Organoleptic characteristics were evaluated in terms of taste, consistency and appearance. Research results have shown that the greatest microbiological risks during storage of cream used as a raw material are associated with lactococci, coliform bacteria and yeast. Microbiological risks caused by seeding of cream with thermophilic streptococcus, spore bacteria of the genus Bacillus and spore anaerobic microorganisms of the genus Clostridium are less significant, which is associated with the lack of development and metabolism of these groups of microorganisms at storage temperatures of 10 ± 1 °C and 4 ± 2 °C. At the same time, the reason for the rejection of cream contaminated with these testing cultures, at a storage temperature of 4 ± 2 °C, is primarily a decrease in organoleptic indicators, and at a temperature of 10 ± 1 °C — an excess in bacterial number.

Food allergens: threshold levels and methodologies for risk management

Food allergies and allergen management are important problems of the public health and food industry. The idea of determining allergen concentrations in food ingredients and food products that are capable of causing severe allergic reactions is of great interest for regulatory bodies as well as consumer associations and the industry all over the world. In this connection, scientists proposed different approaches to determining the basis for assessment of severity of risks of food allergens for health of patients suffering from food allergy similar to methods of risk assessment for other hazards associated with food products (for example, chemical, microbiological). To assess risk of allergens, three different approaches were proposed: i) traditional risk assessment using the no observed adverse effect level (NOAEL)) and uncertainty factors; (ii) approach based on the benchmark dose (BMD)) and margin of exposure (MoE)); and (iii) probability models. These approaches can be used in risk management in food production and in the development of warning marking about the presence of allergens. The reliability of risk assessment will depend on a type, quality and quantity of data used for determining both population threshold levels (or threshold distributions) and an impact of an allergenic product/ingredient on a particular individual.

Use of pullulanase as a biocatalyst for starch hydrolysis: Part 1. Study of the effect of pullulanase on maize amylopectin starch

The use of debranching enzymes in starch hydrolysis is a topical direction for obtaining new types of starch products with controlled properties and a potential for the further use. The aim of the work was to study an effect of pullulanase (EC3.2.1.41) on maize amylopectin starch in the native and gelatinized state. The objects of the research were maize amylopectin starch and enzyme preparation Promozyme D6 (Novozymes, Denmark). High-performance liquid chromatography (HPLC) was used to determine the carbohydrate composition of hydrolysates. The mass fraction of reducing substances (RS) was determined by the Lane and Eynon method. A rotational viscometer was used to measure dynamic viscosity of the starch hydrolysis products. It was found that analyzed starch in the native state showed low enzymatic sensitivity to the action of pullulanase with insignificant changes in viscosity, solubility and iodine binding capacity of the samples. Pullulanase showed the highest effect on gelatinized starch during the first eight hours of incubation. After eight hours, the maximum degree of starch hydrolysis by pullulanase at a dose of 10 units/g dry matter (DM) was 4.7% on DM basis, iodine binding capacity of the hydrolysate was D600 = 0.343 (in the control experiment D600 = 0.154), and the viscosity of the hydrolysate decreased from 7887 mPa · s to 4.3 mPa · s. Hydrolysates cooled to 8 °C and held for 20 hours along with hydrolysates that were not cooled showed high susceptibility to attack by glucoamilase (97–98%) at 60 °C and 24 hours of saccharification, which suggested the absence of their resistance to the action of glucoamilase in the conditions of the experiment. The use of pullulanase in dextrinization of the analyzed starch, which was gelatinized and partly hydrolyzed by α-amylase (RS6.1%), enabled obtaining hydrolysates with the mass fraction of reducing substances in a range of 10–24% on DM basis with the process duration of 2 to 24 hours and the enzyme dose of 2–10 units, which contained mainly maltotriose, maltohexose and maltoheptose with their total amount of 45–60% on DM basis. The results indicate a need for further research of the biocatalytic action of pullulanase to develop new methods for enzymatic modification of starch.

Juice nanotechnology: A mini review

In the past two decades, nano-science is widely used in different applications and the increased interest in the utilization of nanoparticles in food processing is clear. Such applications include processing, packaging, development of functional food, safety, foodborne pathogens detection, and shelf-life extension. In this article, the essential facts and the latest uses of nano-science in fruit and vegetable juices were described. The green synthesis of nanoparticles with antioxidant, antibacterial and antifungal characteristics is of great interest in food preservation. These nanoparticles such as metals, oxidized metals and its bioactivity in juice were reviewed. The current procedures to prepare nanojuice including nanofiltration and the most recent nanomilling were presented. Beside the preparation, special emphasis has also been given to the chemical as well as the biological (microbial and enzymatic) quality of the produced nanojuice. The role of nanotechnology in the development of the smart and the active food packaging systems for the improvement of food shelf- life and quality was also discussed. Since the physical and chemical characteristics of nanoparticles are completely different from those of macro-size. Therefore, special and urgent attention by responsible authorities should be given and effective policies should be applied for food products to ensure product quality, customer health and safety as well as the environmental protection.

Influence of milk-clotting enzymes of animal and microbial origin on the quality and shelf life of soft cheeses

A comparative test was carried out for milk-clotting enzymes (MCE) of animal origin (Naturen® Extra), microbial origin (Marzyme®) and MCE based on recombinant camel chymosin (Chy-max® M) in the production of soft cheese “Lyubitelskiy”. By the end of the shelf life of the cheeses (12 days at a temperature of 3 ± 1 °C), differences were noted in the degree of proteolysis (DP) and the value of the complex modulus G*, which were the following ones for cheeses produced with MCE of the brands: Naturen® — DP = 17.86 ± 0.24%; G* = 4164 ± 587 Pa; Marzyme® — DP = 17.98 ± 0.49%; G* = 4581±786 Pa; Chy-max® M — DP = 9.85 ± 0.63%; G* = 7949 ± 1157 Pa. Cheeses made with Chy-max® M MCE had a denser texture than cheeses made with MCE of Naturen or Marzyme, which did not differ significantly in consistency. In the studied cheeses, the severity of the bitter taste was proportional to the content of water-soluble peptides with a mass of 0.5–3 kDa. Cheeses with Marzyme® MCE had a more intense bitterness than cheeses with Naturen® MCE. There was no bitter taste in cheeses produced with MCE of Chy-max® M. It was concluded that in the production of soft cheeses, recombinant camel chymosin can be used to increase the shelf life, and MCE of microbial origin can be recommended to replace more expensive MCE of animal origin.

Methods for determining color characteristics of vegetable raw materials. A review

Food product quality defines a complex of food product properties such size, shape, texture, color and others, and determines acceptability of these products for consumers. It is possible to detect defects in plant raw materials by color and classify them by color characteristics, texture, shape, a degree of maturity and so on. Currently, the work on modernization of color control systems has been carried out for rapid and objective measuring information about color of plant raw materials during their harvesting, processing and storage. The aim of the work is to analyze existing methods for determining color characteristics of plant raw materials described in foreign and domestic studies. Also, this paper presents the results of the experimental studies that describe the practical use of methods for measuring food product color. At present, the following methods for determining color characteristics by the sensor analysis principle are used: sensory, spectrophotometric and photometric. These methods have several disadvantages. Therefore, computer vision has found wide application as an automated method for food control. It is distinguished by high confidence and reliability in the process of determining freshness, safety, a degree of maturity and other parameters of plant raw materials that are heterogeneous in terms of the abovementioned indicators. The computer vision method is realized in the following systems: conventional, hyperspectral and multispectral. Each subsequent system is a component of the preceding one. Materials presented in the paper allow making a conclusion about the effectiveness of the computer vision systems with the aim of automatic sorting and determining quality of plant raw materials in the food industry.