Modified Gas Atmosphere Research Articles

Development of pH Indicator Composite Films Based on Anthocyanins and Neutral Red for Monitoring Minced Meat and Fish in Modified Gas Atmosphere (MAP)

Development of pH Indicator Composite Films Based on Anthocyanins and Neutral Red for Monitoring Minced Meat and Fish in Modified Gas Atmosphere (MAP)

ХРАНЕНИЕ ТОМАТОВ – ТРАДИЦИОННЫЕ И ПЕРСПЕКТИВНЫЕ ТЕХНОЛОГИИ

As known, tomatoes contain a fairly large amount of biologically valuable substances in their composition. Consumers prefer tomatoes in fresh form. However, being a climacteric crop, tomatoes differ during storage and maturation by a high rate of respiration and evaporation of moisture, which leads to a decrease in valuable nutrients, deterioration in quality, over-ripening and rapid aging, which as a result reduces the marketable appearance of products. Traditional methods of processing tomatoes before storage are not always effective enough to maintain the quality of tomato fruits at the proper level, since it is not always possible to store tomatoes at the recommended low temperature, the necessary relative humidity, etc. In order to increase the storage time of tomatoes while maintaining their quality and safety, it is necessary to search for new modern methods of fruit processing before storage. In this regard, an overview of existing traditional technologies, as well as modern and promising techniques and methods for preparing fresh tomatoes for storage, contributing to the reduction of quantitative losses, preserving qualitative characteristics, is carried out. The most promising methods of preliminary preparation of tomatoes for storage, providing a high level of physical-chemical, organoleptic and microbiological indicators that ensure the safety of stored products are: treatment with ethylene biosynthesis inhibitors and ethylene absorbers, ozonation, modified gas atmosphere, electric field and ultrasound treatment, the use of biological products, the use of active packaging, antimicrobial film-forming coatings, etc. The article describes the work of both domestic and foreign researchers. Keywords: FRESH TOMATOES, PROCESSING, STORAGE TECHNOLOGY, QUALITY

Effect of modified atmosphere package on attributes of sweet bamboo shoots after harvest.

Tender bamboo shoots undergo rapid senescence that influences their quality and commercial value after harvest. In this study, the tender sweet bamboo shoots ('Wensun') were packed by a passive modified atmosphere packaging (PMAP) to inhibit the senescence process, taking polyethylene package as control. The increase in CO2 and the decrease in O2 gas concentrations in the headspace atmosphere of the packages were remarkably modified by PMAP treatments. The modified gas atmosphere packaging inhibited the changes in firmness, as well as the content of cellulose, total pectin, and lignin in the cell walls of bamboo shoots. The enzymatic activities of cellulase, pectinase, and polygalacturonase that act on cell wall polysaccharides, and phenylalanine ammonia lyase, cinnamyl alcohol dehydrogenase, peroxidase, and laccase regulating the lignin biosynthesis were modified by PMAP treatment different from control during storage. The expression levels of the lignin biosynthesis genes PePAL3/4, PeCAD, Pe4CL5, PeC4H, PeCCOAOMT, PeCOMT, cellulose synthase PeCESA1, and related transcription factors PeSND2, PeKNAT7, PeMYB20, PeMYB63, and PeMYB85 were clearly regulated. These results suggest that PMAP efficiently retards the changes in lignin and cell wall polysaccharides, thus delaying the senescence of tender sweet bamboo shoots during storage.

<em>Brochothrix thermosphacta</em> as a microbiological indicator in determining the expiration date of meat products

Microbial spoilage of food products leads to significant losses with negative social and economic consequences. In order to better control contamination and microbiological spoilage of food products, a new GOST P 70354-22 has been introduced. Meat and meat products. General requirements and procedure for testing to justify expiration dates (publication date 09/29/2022). Great importance is attached to the identification and quantification of the additional microbiological indicator Brochothrix termosphacta in meat, meat and meat-containing products packed using vacuum or modified gas atmosphere. Brochothrix sp. may become the dominant type of meat spoilage in MHA packaging and vacuum packed in the presence of sufficient oxygen. Brochothrix causes mucus and stickiness of the meat surface, unpleasant odors. Brochothrix also causes mucus and stickiness on the meat surface. GOST P 70354-22 describes a method for detecting and counting the number of bacteria Brochothrix sp. For their cultivation, a dense selective medium STAA was proposed. It allows you to isolate, identify and determine the amount of Brochothrix in samples. The technique described in GOST P 70354-2022 was tested. According to the results of cultivating primary crops, we observed the growth of characteristic small, round, shiny, gray-white colonies of Brochotrix on the surface of a special medium. The studied bacteria were oxidase-negative and catalase-positive.

Development of a scientific concept of industrial storage systems for environmentally safe apples

The research project has developed and justified the storage modes of apples in a modified gas environment by creating an isolated "closed loop" of high-pressure polyethylene; the expediency of creating highly efficient technologies for storing fresh fruits in a controlled atmosphere, in bioactive bactericidal packages and by creating microfilm on the surface of fruits has been confirmed. The prospects of using a progressive method of storing fruits in a modified gas atmosphere by creating an isolated "closed circuit" in a separate refrigerating chamber without using expensive equipment (in normal and subnormal gas environments) are proved. New technologies have been developed for storing apple fruits susceptible to infectious and physiological diseases based on improved storage methods with minimal losses. The consumption rates of Phytosporin-M for the surface treatment of fruits were determined and optimized to control the intensity of biochemical and microbiological processes during storage. The modes and technologies of post-harvest fruit processing with the Phytosporin-M biopreparation have been substantiated.

Biological method based on track membranes to form controlled gaseous media for fruit cold storage

The article proposes a biological method based on the use of gas-selective track membranes to form a modified gas atmosphere, considering the respiration rate of fruit. The work aims to study the change in the respiration rate of apples depending on the variety and storage time to substantiate the formation of the gas medium composition depending on the respiration rate of the fruit and the area of track membranes, and to study the kinetics of oxidation reactions of biologically active substances during cold storage of apples. The research is based on autumn apple varieties: Grushovka Yudicheva, Kordonovka and Pepin Shafranny. We have obtained the kinetic curves of changes in the content of mono- and disaccharides, ascorbic and organic acids in autumn apple varieties depending on the gas composition in terms of oxygen and carbon dioxide content, as well as the duration of fruit storage using track membranes. For maximum quality preservation, nutritional and biological value of the studied apple varieties at t = (3 ± 1) °C, we have determined a recommended composition of the controlled gas atmosphere: oxygen concentration - (5.2 ± 0.1%), carbon dioxide - (3.6 ± 0.1%). Controlled atmosphere is created using a gas-selective composite membrane with an area of 14-22 cm2/kg, depending on the variety and respiration rate.

Inhibition of Listeria monocytogenes on bologna by a beta acid rich hop extract

Contamination of cold cuts with Listeria monocytogenes pose a risk to human health and frequently cause recalls of affected products. In order to avoid chemical additives for the preservation of ready-to-eat meat products, plant based antimicrobials are currently in demand. Beta acids from the hop plant are known for their strong antimicrobial effects especially against gram-positive bacteria like L. monocytogenes, making them a promising candidate as a functional ingredient. In this study, the antimicrobial activity of a beta acid rich hop extract in combination with sodium nitrite was characterized in vitro, at which the different hurdles of packaged cured boiled sausages were simulated. A complete growth inhibition of L. monocytogenes was found at a minimum inhibitory concentration of 0.2 μg/ml (MIC) when the hop extract was applied in combination with a reduced water activity (aw 0.970), a slightly acidic environment (pH 6) and anaerobic conditions. Under optimal growth conditions (aw 0.995, pH 7, aerobic incubation), the MIC was 16-fold higher (3.2 μg/ml). Sodium nitrite showed a comparably low antimicrobial activity against L. monocytogenes in vitro (MIC > 100 μg/ml). The presence of 1% sunflower oil negatively affected the antimicrobial activity of the hop extract, leading at least to a 32-fold increase of the MIC. The hop extract was subsequently added to a standard recipe of pork bologna at two concentrations. The pork bologna was produced by use of two different cutter processes and then sliced, inoculated on the surface with a two strain mixture of L. monocytogenes and stored at 7 °C under modified gas atmosphere for 28 days. At 0.4 g/kg of hop extract, L. monocytogenes populations were reduced up to 3 orders of magnitude in relation to bologna without hop extract while 0.8 g/kg of hop extract either prevented the growth of L. monocytogenes or resulted in at least 4 orders of magnitude lower final populations. There was no significant sensory deviation of hop bologna according to performed triangle tests (α = 0.05) and the product color remained unaffected. Based on the presented results, the use of beta acid rich hop extracts can be proposed as an additional hurdle to inhibit the propagation of L. monocytogenes on packaged ready-to-eat cold cuts like bologna.

ЕФЕКТИВНІСТЬ ПОПЕРЕДНЬОГО ОБРОБЛЕННЯ ЯГІД СУНИЦІ РОЗЧИНОМ ХІТОЗАНУ ЗА ХОЛОДИЛЬНОГО ЗБЕРІГАННЯ В МОДИФІКОВАНОМУ ГАЗОВОМУ СЕРЕДОВИЩІ

Strawberries (Fragaria ananassa) belong to short-term berries. Many technologies are used to extend its shelf life. One of the current technologies is the use of pretreatment of berries with polysaccharide solutions before refrigerated storage. This treatment makes it possible to reduce weight loss and improve the overall quality of berries by forming a protective barrier film on their surface. The purpose of this study was to investigate the effectiveness of chitosan strawberries pre-treatment while storing it in a refrigerated chamber using a modified gas atmosphere. To achieve the purpose, strawberries were treated with 0,05 %; 0,2 %; 0,5 % aqueous solutions of low molecular weight chitosan were stored in a refrigerator at t 0 + 2 °C using polyethylene bags of 30 microns thickness. Unprocessed berries were used as a control. All experimental studies were performed in triplicate. According to the research results it was found that the weight loss of treated berries was 1,48 – 5,11 % and in the control 11,35 %. The mass fraction of sugars at the end of storage in the treated berries was (2,2–2,6 %), which is 0,2–0,6 times higher than in the control.. The content of ethyl alcohol is fixed in all samples. In the control variant, it was 0,87 %, and in the samples the treatment was from 0,57 – 0,8 % According to the results of the tasting evaluation, the best performance was in the sample with a concentration of 0,5 % Pretreatment of strawberry berries with aqueous solutions of low molecular weight chitosan has a positive effect on the quality of strawberry berries and can be used as an effective tool in the storage of berries

Justification of selection of packaging material and packing method for preservation of vitamin-mineral concentrate quality

In the production of quality food products, special attention must be paid to its packaging and storage. These process steps are especially important for products containing labile biologically active substances. In order to select packaging materials and packing method, an analysis of the scientific literature was conducted with the search query “packaging materials for foodstuffs” and “the effect of packaging on the preservation of vitamins during food storage” in the Google Scholar system. The article presents trends in the development and use of packaging materials, reflects the advantages and disadvantages of biopolymers, as well as prospects for improving the characteristics of packaging materials. As an example, for the choice of packaging material and packing method, data from Russian scientists based on packaging materials used in the Russian Federation is given. Storage of beef steaks in bags with reduced gas permeability under vacuum and a modified gas atmosphere with a reduced content of free space for 14 days contributes to the inhibition of bacteria. Storage of sterilized and ultra-pasteurized milk is preferably in bags of a three-word film filled with titanium dioxide, in comparison with glass packaging, due to a decrease in light transmission and a decrease in the rate of decomposition of vitamin C. It is preferable to store orange juice in packages of combined materials that exclude the presence of an air cushion, which positively affects the content of vitamin C. Based on the analysis of packaging materials used in the food industry and taking into account the humidity and chemical composition of the vitamin and mineral concentrate, it seems appropriate to use packaging materials made of polymer films with high light and gas impermeability, which can reduce the rate of destruction of vitamin C and other easily oxidized components and eliminate the use of ? -radiation, replacing it by evacuation. The use of edible films for vitamin and mineral concentrate as packaging materials remains open and requires more careful study.

Quality index of raw gilthead sea bream

Sensorial, biochemical and microbiological methods were used in order to evaluate the quality of the raw gilthed sea bream. Whole fish was stored in ice and in modified gas atmosphere consisting of 70% carbon dioxide and 30% nitrogen. At regular intervals during refrigerated storage Malondialdehyde- MDA^g/kg), Total Volatile Bases-N - TVB-N (mg/100g), odour and flavor scores and various types of micro-organisms were determined. Fatty acid contents were also measured along the cold storage. The results showed that the quality parameters used for the evaluation of raw gilthed sea bream could form a preliminary model for quality index of farmed euryhaline fin fish in our country.

Effects of different storage conditions on quality related porphyrin fluorescence signatures of pork slices

This study evaluated the potential of fluorescence as an indicator of pork quality by determining the effects of various conditions on fluorescence signatures (excitation at 420nm, emission at 550–750nm).Storage of porcine musculus longissimus dorsi in PE bags led to a clear increase in porphyrin fluorescence intensity after approx. 10d post mortem. Modified gas atmosphere (70% O2, 30% CO2) inhibited the fluorescence emission of zinc protoporphyrin and protoporphyrin IX due to quenching by oxygen. Bleaching processes caused similar effects by halogen light exposure during meat storage. However, already formed signals could not be manipulated by oxygen or halogen light. Storage under vacuum reduced the quenching effects and resulted in increased fluorescence intensities. Freezing and thawing of meat samples delayed and reduced the increase in fluorescence intensity. Only minor effects could be detected at long-term frozen storage for two months.Consequently porphyrin fluorescence analysis is a potential means to indicate changes of pork quality and remaining shelf life.

Reduction of Campylobacter jejuni counts on chicken meat treated with different seasonings

To analyze the potential of various seasoning combinations in reducing Campylobacter jejuni counts on fresh chicken meat, fresh chicken drumstick samples were inoculated with a mixture of two C. jejuni strains at log 4–5 CFU/g and subsequently treated with six different seasonings. After addition as a dry powder to the meat’s surface, all seasoning combinations adsorbed water from the meat and formed a gel on the meat’s surface. The samples were placed in individual packages containing a modified gas atmosphere (N 2 80% and CO 2 20%) and stored at 4 °C for seven days and C. jejuni counts in CFU/g were determined at the beginning, after 15 min, 1 h, 1 day and 7 days. The most effective seasoning combination contained, among other ingredients and food additives, sodium lactate and potato protein fractions; it reduced counts by mean 1.52 to 1.66 log CFU/g in seven days. The other seasoning combinations without potato protein fractions decreased counts in the range of mean 1.05 to 1.16 log CFU/g; simultaneously, the counts in control meat samples decreased by mean 0.21 log CFU/g. The death rate estimates after 1 h storage was in the range of −0.25 log CFU/g/h to −0.34 log CFU/g/h. In conclusion, various combinations of seasonings decreased the counts of C. jejuni, with the highest C. jejuni death rate during the first hour and further minor reductions in C. jejuni counts with additional storage time. These types of treatments may decrease human exposure to Campylobacter from fresh poultry meat.

A method for the growth and recovery of 17 species of Campylobacter and its subsequent application to inoculated beef

The aim of this study was to develop a universal cultural protocol, which could facilitate the growth of 17 species and 3 subspecies of Campylobacter. Enrichment media including Campylobacter Enrichment Broth (CEB) and Bolton Broth were tested against a panel of Campylobacter strains (n=53) encompassing 17 species and 3 subspecies, under a gas atmosphere containing hydrogen (2.5% O2, 7% H2, 10% CO2, and 80.5% N2). The impact of enrichment conditions on cell motility was also investigated using fluorescent microscopy. Membrane filtration was examined as a means of selectively recovering Campylobacter from enrichment media on two different non-selective agars, Anaerobe Basal Agar (ABA) and Tryptose Blood Agar (TBA). The results showed that enrichment in CEB for 24h at 37°C under a modified gas atmosphere followed by centrifugation and membrane filtration onto ABA allowed recovery of all species (53 strains) of Campylobacter from inoculated meat samples. After 24h enrichment, there were higher levels of motile Campylobacter in CEB than in Bolton broth and it is proposed that this attribute aided the passage of the Campylobacter through the membrane filter. The results of this study provide a simple, but effective method for the growth and recovery of a wide range of diverse Campylobacter spp. from a meat matrix using common cultural parameters.

THE EFFECT OF PROCESSING METHOD AND STORAGE TIME ON CONSTITUENTS OF TURKISH SAUSAGES (SUCUK)

Turkish sausages (sucuk) were produced by two methods (heat processing and traditional). Their moisture, pH and water activity and lipid stability were studied during refrigerated storage (4 ± 2C/90 days). Heat-processed (Therm) sausages had higher moisture content, water activity and pH values, and low thiobarbituric acid (TBA) values, free fatty acids (FFA) and peroxide values. FFA content of Therm sausages increased from 2.5 to 5.5% during storage and was significantly (P < 0.05) affected by storage time. In the case of traditionally produced (Trad) sausages, there was no significant impact of storage time, but their TBA value increased from 0.38 to 0.48 mg MA/kg, while only a slight increase was observed in Therm sausages, from 0.41 to 0.43 mg MA/kg. Storage time significantly (P < 0.05) increased the TBA value of Trad sausages. PRACTICAL APPLICATIONS In the current study, the effect of processing methods (heat processing and traditional) and storage time on some constituents of Turkish sausages was studied. Processing method significantly affected proximate composition of the sausages. On the other hand, lipolytic and oxidative changes were observed in both heat-processed and traditional sausages during storage. This could be attributed to hydrolytic enzymes and residual oxygen in vacuum packs. In practical applications, low oxygen permeability packing materials or modified gas atmosphere packing are recommended for both processing methods.

Effects of modified gas atmosphere packaging on pork loin colour, display life and drip loss

Boneless loins from both sides of 20 pig carcasses were divided into five sections each and assigned equally to five packaging treatments: 100 % CO 2; 50 % CO 2/50 % N 2; 25 % CO 2/ 75 % N 2; 25 % CO 2/65 % N 2/10 % O 2 and vacuum. Loin sections were packaged in bags of low O 2 permeability, then stored in darkness at 1 °C for up to 22 days. Retail chops were cut from the sections and displayed in oxygen-permeable film under light at 3 °C for 3 additional days. The O 2 concentrations in packages with nominally anoxic atmospheres were 0.1–0.4 %. Sections stored in 25 % CO 2/65 % N 2/10 % O 2 had more surface greying and greening, stronger off-odour and psychrotropic counts after storage were more than one log 10 higher compared to sections from the other four treatments. Displayed chops from sections stored in 25 % CO 2/65 % N 2/10 % O 2 also had greying/greening at an outer layer of the chops. Off-odour of chops was most pronounced for treatments with 10 % O 2 and vacuum. Drip loss from loin sections was highest for those in 100 % CO 2 (4.2 %) and lowest for those in vacuum (3.2 %). In conclusion, storage in CO 2 or CO 2 N 2 atmospheres benefitted the overall shelf life of pork.

Physical characteristics of lamb primals packaged under vacuum or modified atmospheres

Lamb primals (shoulders) were packaged under vacuum, 80% O 2/20% CO 2, 50% CO 2/50% N 2 or 100% CO 2 and stored at 5 or 0 °C. Pack contents were examined at 7 day intervals to determine the composition of the pack atmosphere, drip loss, colour (muscle and fat) and pH (surface and internal). The composition of the gas atmospheres changed very little during storage. The only significant differences between developed head space compositions above primals stored at the two different temperatures (5 and 0 °C) were noted in packs stored for 28 days under 80% O 2/20% CO 2. Low levels of drip loss (<0.5%) were noted in all packs stored under the modified gas atmospheres. In contrast, significantly higher levels of drip loss (0.5–1.1%) were noted in vacuum packaged lamb stored at 5 and 0 °C. Acceptable muscle colour was observed 2 hr after opening of all packs. The only significant differences between atmospheres for lean muscle colour were noted after 28 days storage. Fat colour did not generally change during storage in any of the atmospheres, apart from a slight bleaching effect at 7 days. There were no significant differences between the surface or internal pH values noted after storage under any of the atmosphere/temperature combinations. In general, higher pH values were observed at the surface of the meat than in the interior. This pattern was noted before and after storage.

Effect of gas barrier characteristics of films on aflatoxin production by Aspergillus flavus in peanuts packaged under modified atmosphere packaging (MAP) conditions

The effects of the gas barrier characteristics of three films (ASI, ASII and ASIII) and storage temperature on the growth of, and aflatoxin production by, Aspergillus flavus in peanuts packaged in air and under a modified gas atmosphere of CO 2:N 2 (65:35) were investigated. Mold growth was barely visible in air packaged peanuts using high-medium barrier films (ASI and ASII) and stored at 20°C with more extensive growth occurring in air packaged peanuts stored at 25 and 30°C. Extensive mycelial growth and sporulation occurred in all air packaged peanuts in a low barrier film (ASIII), especially at 30°C. Gas packaging inhibited mold growth in peanuts packaged in a high gas barrier film at 20°C. However, mold growth occurred in gas packaged peanuts packaged in film ASII at higher storage temperatures while extensive mycelial growth was observed in all peanuts packaged in film ASIII irrespective of storage temperature. Levels of aflatoxin greater than the regulatory limit of 20 ng/g were detected in all air packaged peanuts with the highest level of aflatoxin (∼76 ng/g) being detected in peanuts packaged in a high gas barrier film ASI. Aflatoxin production was inhibited in gas packaged peanuts using a high barrier film. However, higher levels of aflatoxin were detected in all gas packaged peanuts in medium-low gas barrier films (ASII and ASIII), particularly at higher storage temperatures. This study has shown that MAP using a CO 2:N 2 (65:35) gas mixture was effective in controlling aflatoxin production by A. flavus in peanuts to levels less than the regulatory limit of 20 ng/g. However, the antimycotic effect of low O 2-high CO 2 atmospheres is dependent on the gas barrier characteristics of the packaging films, especially at higher storage temperatures.

Survival and Growth of Listeria monocytogenes and Yersinia enterocolitica in Pork Chops Packaged under Modified Gas Atmospheres

ABSTRACT Listeria monocytogenes Scott A, serotype 4b, and Yersinia enterocolitica from vacuum‐packaged pork were inoculated onto fresh pork chops. Survival and growth were determined in different atmospheres at 4 °C during 35‐days. Atmospheres were gas mixtures [20/0/80, 40/ 0/60, and 40/10/50 (CO2/O2/N2)], vacuum and air. In air L. monocytogenes and Y. enterocolitica grew slower than psychrotrophic spoilage flora. In gas atmospheres, Y. enterocolitica grew at the same rate as psychrotrophic spoilage flora and L. monocytogenes grew more slowly. When 10% O2 was included in the 40% CO2 mixture, growth was reduced. Vacuum packaging was no more effective than gas mixtures in retarding growth. Modified atmospheres provide an environment in the package that would allow growth of Y. enterocolitica and potentially compromise safety of meat products.

Effects of modified atmosphere packaging and carcass chill rate on pork loins (1990)

Use of 10% oxygen in a modified gas atmosphere package resulted in more off-odor, higher microbial counts, and a less desirably colored loin and loin chops. Furthermore, it reduced chop display life and is not recommended.; Swine Day, Manhattan, KS, November 15, 1990

Storage Life of Selected Meat Sandwiches at 4°C in Modified Gas Atmospheres

The refrigerated storage life of selected meat sandwiches packed in elevated carbon dioxide atmospheres with air or nitrogen was studied by acceptability scores of untrained panelists and by microbiological analysis. Commercially produced sandwiches, including processed meats, roast beef and hamburgers, were packed in gas impermeable film with 50% CO2 and 50% air, stored at 4°C, and compared with a frozen reference sample. Processed meat products were still acceptable up to 35 d storage, roast beef for 28 to 35 d storage, and hamburger for only 14 d. The effect of gas atmospheres with 30, 50, or 70% CO2 and either air or nitrogen, on acceptability of laboratory-packaged bologna, ham, roast beef, and hamburger, was also studied. The most significant effect was observed with hamburger samples, in which exclusion of oxygen extended storage life from 14 to 35 d. Initial product quality was a more important factor determining the length of storage life than the range of gas atmospheres between 30 and 70% CO2, except for hamburger packaged in atmospheres containing air. A universal storage life for these products cannot be recommended. However acceptance of the products by an untrained taste panel generally extends beyond achievement of maximum microbial load.