Spoilage Indicators Research Articles

Consumer Perception of Freshness and Volatile Composition of Fresh Gilthead Seabream and Seabass in Active Packaging with and without CO2-Emitting Pads.

Active packaging with CO2-emitters (pads) has recently been used for shelf-life extension of fresh fish. The aim of this study was to identify consumer attitudes towards fresh fish packaging, to examine whether Greek consumers prefer active packaging with pad over active packaging without pad, to investigate any perceived differences in the sensory freshness of the fish, and to relate consumer perception to volatile composition of fish fillets. In total, 274 consumers participated in the study which included freshness sensory evaluation of gilthead seabream (Sparus aurata) and seabass (Dicentrarchuslabrax), whole-gutted and filleted, raw and cooked, at high quality and at the end of high-quality shelf-life. Samples were packed under modified atmosphere either with a pad or without. Results showed that consumers preferred packages with pads, especially at the end of high quality shelf-life. They perceived raw samples packed with a pad to be fresher and closer to the ideal product, and also had a higher purchase intention towards them. Cooked samples were not perceived differently. Consumers' perception was in accordance with the GC-MS findings in the volatile compounds that function as freshness or spoilage indicators. Most participants were positive towards fresh fish packaging although they usually buy unpacked fresh fish. Our results suggest that active packaging with CO2 emitters contribute to freshness preservation and that it has a positive potential in the Greek market.

Electronic-free and low-cost wireless sensor tag for monitoring fish freshness

Real-time monitoring of fish products throughout the supply chain is critically important for proper tracking of fish quality and spoilage to eliminate food waste. However, most of the existing food freshness monitoring technologies are based on complex and costly sensors that lack specificity to direct biomarkers of product quality rendering them impractical for scalable low-cost production and integration into standard food packaging products. To address these issues, we present an electronic-free wireless sensor tag that can selectively monitor hypoxanthine (HX) as a specific biomarker to indicate the spoilage of fish products. The sensor tag is composed of a working and reference coil in a self-calibrating, dual-resonator configuration. The working coil is covered with a stimuli-responsive bilayer polymer structure that degrades only when high levels of HX are produced in spoiled fish products, resulting in a discernible change in the resonant characteristics of the coil. Detecting this change with respect to the reference antenna using a contactless external reader provides a differential mode of sensing to avoid environmental noise and enhance accuracy. The sensor fabrication process takes advantage of scalable and cost-effective manufacturing technologies including laser processing of metalized films and solution casting approaches. Systematic design of resonant coils and optimization of functional HX responsive coatings were performed to identify structures that provided the required spoilage detection threshold of (>2.25 mM HX) which is an indicator of fish spoilage in package products. As a proof of concept, the sensor tag’s performance was validated in a commercially packaged fish product, highlighting its ability to effectively differentiate spoiled products from fresh products in refrigerated conditions. The high selectivity exhibited by this technology puts forth a new platform that merges stimuli-responsive sensing with electronic-free wireless telemetry to develop biomarker-specific sensors for a wide range of intelligent food packaging applications.

Profiling the composition and metabolic functions of microbial community in pellicle-forming radish paocai

Pellicle formation is an obvious indicator of spoilage and is followed by a loss of flavor in a variety of fermented vegetables. In this study, the pellicle-forming microorganisms were isolated using culture-dependent approaches, then a comparative analysis between the pellicle-forming (PF) radish paocai and normal fermented paocai in the diversity and function of microbial community was conducted by metagenome sequencing. Based on a pairwise t-test and OPLS-DA analysis, diallyl sulfide, (z)-1-allyl-2-(prop-1-en-1-yl) disulfane, and terpineol were considered to be the main components responsible for the unpleasant flavor of PF paocai. Yarrowia spp., Enterobacter spp., and Pichia spp. were the main pellicle-forming microorganisms. All 17 isolated Enterobacter strains showed pectinase-producing and cellulase-producing abilities, and 3 isolated Pichia strains showed gas-producing capacity. According to LEfSe analysis based on metagenomes, unclassified_g__Citrobacter and Yarrowia lipolytica were the uppermost biomarkers that distinguished the PF paocai from normal paocai. Unclassified_g__Lactobacillus and Lactobacillus plantarum were found to be actively engaged in starch and sucrose metabolism, cysteine and methionine metabolism, galactose metabolism, fructose and mannose metabolism, lysine biosynthesis, fatty acid biosynthesis, and arginine biosynthesis, all of which contributed to the flavor formation of paocai. Combining the results of metagenome sequencing with the data obtained based on the culture-dependent method, we could deduce that the growth of Yarrowia lipolytica first promoted the increase of pH and the formation of pellicle, which provided a suitable niche for the growth of some harmful bacteria such as Enterobacter, Citrobacter, and Serratia. These hazardous bacteria then worked in concert to induce the odorous stench and texture softening of paocai, as well as more pellicle formation.

Growth and Volatile Organic Compound Production of Pseudomonas Fish Spoiler Strains on Fish Juice Agar Model Substrate at Different Temperatures

Microbial spoilage is the main cause of quality deterioration in seafood. Several strains of psychotropic Pseudomonas have been found to dominate in such products, producing a plethora of volatile organic compounds (VOC). Herein, we investigated the growth of and VOC production by seven strains of Pseudomonas associated with spoiled fish after inoculation as single and mixed cultures on model fish substrate and storage at 0, 4 and 8 °C. The results indicated a strain-dependent VOC profile that was also affected by the storage temperature. Hierarchical cluster analysis (HCA) successfully grouped the strains based on VOC profile at each studied temperature, while some potential Chemical Spoilage Indices (CSI) were revealed. The findings of the present work will contribute to the understanding of the metabolic activity of particular strains of Pseudomonas and to reveal any potential CSI for rapid evaluation of fish spoilage/freshness status.

Quality assessment of fermented soybeans: physicochemical, bioactive compounds and biogenic amines

In this research, a total of 47 samples from five types of fermented soybeans were selected. The physicochemical parameters, biogenic amines (BAs) and bioactive compounds such as isoflavones, total phenolic (TPC) and γ-aminobutyric acid (GABA) were investigated. The results showed that the contents of isoflavones ranged from 598.06 mg/kg to 2725.03 mg/kg in all samples and it varied from 598.96 mg/kg to 2241.67 mg/kg in Semen Sojae Preparatum (SSP) which was higher than other types of fermented soybeans. The maximum variation of GABA content was found in Aspergillus-type douchi (AD) samples. The maximum value of TPC in SSP was 4.53 g/kg. For BAs, the indicator of spoilage, 4.26% of fermented soybeans samples may lead to histamine poisoning and 42.55% of samples with total BAs contents exceeding 100 mg/kg may be harmful to human body. It indicated that different types of fermented soybeans had various bioactive compounds and BAs, so different fermented soybeans could be selected according to bioactive substances. This finding could provide comprehensive information of health beneficial compounds and BAs risks of fermented soybeans. It could guide consumers to select healthy, nutritious and safety fermented soybeans.

Study on Volatile Chemicals as Spoilage Indexes of Salmon by HS-SPME-GC-MS Technique during Non-Frozen Storage.

Freshness is the most fundamental and important factor to assess raw fish quality. The purpose of our study was to determine the potential spoilage indexes of salmon during non-frozen storage by using headspace solid-phase microextraction (HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS). More than 300 volatile compounds in salmon were detected when sensory scores declined gradually following the quality changes of salmon at different temperatures. And there were 27 and 31 compounds that showed concentration variations when stored at 4 °C and 25 °C, respectively. Among them, the contents of 1,3-di-tert-butylbenzene, acetic acid, and 3-methyl-1-butanol increased significantly in the later storage period and were in accordance with the salmon's qualities. The present study provides valuable information on the volatile chemical spoilage indexes that are closely related to the freshness of salmon, which may provide an efficient alternative way for quality evaluation of salmon.

Novel perspective on the spoilage metabolism of refrigerated sturgeon fillets: Nonspecific spoilage dominant organisms play an important role

Aeromonas sobria, a specific spoilage organism (SSO) in refrigerated (4 °C) sturgeon fillets, is considered as the main contributor for sturgeon spoilage. However, the spoilage metabolism of A. sobria is influenced by bacterial interactions, and the effect of nonspecific spoilage dominant organisms on the spoilage metabolism of A. sobria during storage is still unknown. In this study, the spoilage characteristics and metabolite changes of different inoculation groups under chilled storage were investigated through a co-cultivation model. The results of spoilage indicators indicated that the microbial interactions changed the spoilage characteristic of the fish model, although A. sobria played the most important role. Based on metabolome results, 549 differential metabolites were identified in two ion modes, which involved 9 chemical categories and 4 main metabolic pathways. The nonspecific spoilage dominant bacteria M. caseolyticus in the early stage of refrigeration affects the amino acid metabolism pathways of fish model by secreting extracellular proteases and peptidases. However, the nonspecific spoilage dominant bacteria A. albensis in the later period of refrigeration accelerate the lipid metabolism, and amino acid metabolism via secreting extracellular peptidases, lipase and esterase. This work may provide insights on controlling the spoilage of aquatic products by intervening degradation pathways.

Berry anthocyanin-based films in smart food packaging: A mini-review

Smart packaging is an emergent technology in food industry, incorporating intelligent and active materials capable to detect spoilage in real-time and extend the food shelf-life. The current trend is to create sustainable packs made of biopolymers and extracts of anthocyanins, the polyphenol pigments of plants endowed with antioxidant activity and pH-responsive properties to monitor microbial food deterioration. Indeed, a large number of articles were published about anthocyanin films over the last decade, nevertheless, none study categorizes the films by the type of source of anthocyanin extracts (vegetables, fruits, flowers). Thus, this review summarizes the state-of-the-art of smart packaging films based on anthocyanin extracts from berries, namely, their preparation, characterization, and validation in real systems. Various berries from Ericaceae (blueberry), Rosaceae (blackberry), and other families (mulberry) have been integrated into food films, mostly by casting technique. The films are described in terms of morphology, mechanical, and physicochemical features, and validated as pH intelligent indicators of food freshness, or active packs against lipid oxidation. Some anthocyanin films emerge like “dual-functional packaging”, but stability studies (temperature, light) are required to their industrial scale-up nowadays. • Food packaging films based on anthocyanin extracts from berries. • Films reviewed pursuant to the taxonomic family of berry-producing plants. • Films were prepared by casting and validated as pH indicators of food spoilage. • Future outlook over their intelligent and active applications in industry.

Anthocyanins of Açaí Applied as a Colorimetric Indicator of Milk Spoilage: A Study Using Agar-Agar and Cellulose Acetate as Solid Support to Be Applied in Packaging

Food that is still fit for consumption is wasted in the domestic environment every day, so food packaging technologies are being developed that will monitor the quality of the products in real time. Highly perishable milk is currently one of the products that suffers most from this waste, due to its short shelf life. Active use-by date (AUBD) indicators have been shown to discriminate between fresh and spoiled milk. Colorimetric indicators undergo characteristic changes in their chemical structure, causing abrupt color changes. Among the polymeric materials studied that may function as solid support are cellulose acetate (CA) and agar-agar (AA). The AA colorimetric indicator proved to be more suitable as a solid support due to its ability to maintain the color change properties of the anthocyanin and its high colorimetric performance. The technique was shown to be capable of indicating, in real time, changes in milk quality.

Evaluation of sensory and chemical quality difference of frozen gadus morhua in open markets of Imo state, Nigeria

A total of forty (40) frozen Gadus morhua obtained from cold room and open markets of three Local Government areas of Imo state were evaluated for their sensory qualities employing the use of nine panelist guided by questionnaire on general appearance, taste, smell and texture and chemical quality changes in their ammonia (AMM), total volatile base nitrogen (TVB-N), trimethylamine nitrogen TMA-N), acid value (AV), free fatty acid (FFA) and pH at the hands of the final consumers. Results were analysed using a one way analysis of variance employing SPSS package and compared using the Duncan multiple range test. Results shows that frozen Gadus morhua obtained from the cold rooms and open markets in the three local government areas under study had very good qualities for general appearance of 1.22±0.56 and 2.40±0.72 as the highest mean respectively. The very good quality still persists in the grilled (cooked) samples of the fish. A significant difference in AMM, TVB-N, TMA-N, AV and FFA at p≤0.05 with p-values of 0.00, 0.00, 0.00, 0.00 and 0.02 respectively was recorded while pH values remained insignificantly different at p-value of 1.00. During the fish storage in ice, volatile compounds such as ammonia (NH3) and trimethylamine (TMA), are produced by autolytic and bacterial processes, resulting in an ammoniacal and strong fish odour, typical of deteriorated fish. These parameters generally are indicators of fish spoilage. Significant rise in Ammonia value from 15.65 0.04 for cold room samples to 20.96 0.78 from an open market in Ohaji LGA and TMA-N cold room values of 2.46 ± 0.39 to 3.95 ± 0.45 from an open market indicating fast rate of spoilage which is concluded to be due to the unsafe exposure of fish and its handling after it must have left the cold rooms. Even though the values obtained in open markets were still good, quality loss was signiificantly observed. It is recommended that sanitary and food inspection agencies resume function in our markets to reduce the risk of fish contamination which subsequently reduces its quality.

Determination of hydrogen sulfide in samples of rainbow trout (<i>Oncorynchys mykiss</i>) using "SmartBiotic"

By now biological additives are used in almost all branches of agriculture to improve the quality and safety of food products.Fish is a perishable product due to its biochemical composition. One of the indicators of fish spoilage is the detection of hydrogen sulfide in samples. The purpose of our study was to determine the effect of the use of the drug "SmartBiotic", produced on the basis of humic acids, on the quality and safety of the fish products obtained, namely, the detection of free ammonia in the selected samples of rainbow trout. Three groups of rainbow trout fingerlings (Oncorhynchus mykiss) were formed to conduct the study. One group served as a control, and the other two were experimental subjects. The first experimental group of fingerlings received the drug at a concentration of 0.15%, and the second experimental group – at a dose of 0.25%. In the control group of rainbow trout, the drug "SmartBiotic" wasn’t used.

Development and Performance Evaluation of a Solar Powered Tomatoes Storage Chamber

Fresh vegetables and fruits, most of which are perishable, are known to be good sources of nutrients supplements with health benefits. Tomatoes fruits fall into this category of food supplements. However, the post-harvest losses associated with tomatoes fruits have greatly reduced the profitability of its farming and have even scared some farmers away from producing it. To reduce the losses and encourage tomatoes farming, this study designed, constructed, and evaluated the performance of a solar-powered electronic storage chamber for tomatoes fruits. In the performance evaluation, the weight, firmness, ripening index, and rate of spoilage of tomatoes fruits stored, within six weeks, at room temperature and atmospheric humidity and in the storage chamber were analyzed and compared per week. The results showed that the weight and firmness of the test experiment deteriorated by 24.87% and 20.83% respectively while that of the control experiment deteriorated by 50.59% and 79.68% respectively. Also, the percentage of cumulative spoilage for the test and control experiment was estimated to be 23.32 and 68.84 respectively showing a significant reduction in the rate of spoilage when the tomatoes were stored in the chamber.

Effects of Turmeric, Cinnamon, and Lemon Extracts on Shelf Life, Nutrients, and Preservation of Carp Fish in Cold Storage

The present study aimed to investigate the effect of extracts of turmeric, cinnamon, and lemon on shelf life, macronutrients, and oxidative spoilage of the carp fish in cold storage at 4°C. Fishes were divided into five groups: control (NT); immersed fish in extracts of cinnamon, turmeric, and lemon (CTL); immersed fish in extracts of lemon and turmeric (LT); immersed fish in extracts of cinnamon and turmeric (CT); and immersed fish in extracts of lemon and cinnamon (LC). Results showed immersion of the carp fillet in extracts of turmeric, cinnamon, and lemon improved spoilage indices such as thiobarbituric acid, volatile nitrogen bases, and pH. The used extracts maintained the nutritional value and increased the fish’s shelf life. The compounds existed in the studied extracts decreased the values of the spoilage indices during cold storage. The highest spoilage indices were found for CL and CT treatments, and the lowest was for CTL treatment. The total bacterial load as well as the number of psychrophilic bacteria in the fish fillet found a significant decrease compared to the NT. Therefore, the best treatment was CTL, and inappropriate treatments were CT and CL. The fish shelf life for nine days was extended with the used extracts because the total count of cryophilic bacteria was 0.41 × 104 ± 0.50, which was the lowest compared to other treatments.

A novel method for real-time prediction of the shelf life of pork at different storage temperatures using front-face fluorescence excitation-emission matrices

This study presents a novel method for predicting the shelf life of pork in real-time based on front-face fluorescence excitation-emission matrices (EEMs). The total viable count (TVC) of bacteria was used as the indicator of microbial spoilage in the pork samples. Modified Gompertz and square root equations were used to establish models for the trends in microbial growth and for predicting the shelf life, the R2 values of the fitting equation at different temperatures were all greater than 0.95. The fluorescence intensity ratio of oxidation product to tryptophan (FOX/Trp) was highly correlated with the quality deterioration of pork and was therefore used to establish a quantitative model of TVC values by linear regression with Rc2 and Rp2 values of 0.914 and 0.906, respectively. The mean absolute errors between the remaining shelf life predicted by fluorescence EEMs and the measured values at three storage temperatures were less than 1 day.

Raman spectroscopic techniques for meat analysis: A review

Raman spectroscopy (vibrational spectroscopy) proved to be an effective analytical approach in the field of geology, semiconductors, materials and polymers. Over the past decade, Raman spectroscopy has attracted the attention of researchers as a non-destructive, highly sensitive, fast and eco-friendly method and has demonstrated the unique capabilities of food analysis. The use of Raman spectroscopic methods (RSMs) to assess the quality of meat and finished products is rapidly expanding. From the analysis of one sample, you can get a large amount of information about the structure of proteins, the composition of fatty acids, organoleptic parameters, autolysis and spoilage indicators, authentication of raw materials, technological properties. An important advantage of the method is the comparability of the results obtained with the data of traditional analytical methods. Traditional methods of determining the quality of meat are often time-consuming, expensive and lead to irreversible damage to a sample. It is difficult to use them in production conditions directly on the meat processing lines. Technological advances have made it possible to develop portable Raman spectroscopes to use directly in production. The article presents the basic principles of Raman spectroscopy, system atizes the results of the use of RSMs for the analysis of meat quality from different types of slaughter animals and provides tools for analyzing the data of the obtained spectra. Raman spectra have many dependent variables, so chemometric assays are used to work with them. Literature analysis has shown that currently there is no unified database of meat spectra in the world, standardized protocols for conducting research and processing the obtained results. In Russia, the use of RSMs is a new,

Effect of Different Degrees of Deep Freezing on the Quality of Snowflake Beef during Storage.

In order to elucidate whether deep freezing could maintain the quality of snowflake beef, three different deep freezing temperatures (−18 °C, −40 °C, and −60 °C) were used in order to evaluate the changes in tissue structures, quality characteristics and spoilage indexes, and their comparative effects on the quality of snowflake beef. Compared to samples frozen at −18 °C, those stored at −40 °C and −60 °C took a shorter time to exceed the maximum ice crystallization zone (significantly reduced by 2–6 h). In terms of short-term storage, samples frozen at −40 °C and −60 °C had better tissue structure and lower drip loss rate than those frozen at −18 °C; significant differences between groups in drip loss were observed between −18 °C and −60 °C. Moreover, a better bright red color and lower shear force were maintained at −40 °C and −60 °C, with significant differences in shear force between the −18 °C group and the other two groups on day 60. Although there were significant effects on the inhibition of lipid and protein oxidation at −40 °C and −60 °C; no significant variation was observed between these two groups throughout storage. A similar phenomenon was found in flavor, with 1-pentanol identified as an important potential indicator of flavor change in snowflake beef during storage. This study demonstrated that −40 °C and −60 °C had favorable impacts on the quality maintenance of snowflake beef compared to −18 °C. These findings provide a theoretical basis for effective stability of snowflake beef quality during frozen storage.

Assessment of Biogenic Amines in Milk and Selected Milk Products

Background: Biogenic amines (BAs) are low molecular weight organic bases with biological activity that are formed in foods by microbial decarboxylation of the corresponding amino acids or by transamination of aldehydes and ketones by amino acid transaminases. As these BAs are toxic and act as a spoilage indicator, their presence determines the quality of food. Methods: Milk and selected milk products were assessed for the presence of selected BAs such as histamine, tyramine, tryptamine, spermine, spermidine, cadaverine and putrescine using HPTLC. Result: It was observed that histamine, spermidine and tryptamine were present in the raw as well as pasteurized milk of cow and buffalo. Pasteurised milk found to show low concentration of tryptamine than the raw milk. Cheese was found with the presence of histamine, tryptamine and putrescine throughout the storage. Though, BAs are present within safe limit in all the milk and selected milk products but their presence indicates a serious quality concern.

РАЗРАБОТКА РЕЦЕПТУРЫ И СРАВНИТЕЛЬНАЯ ОЦЕНКА КОНДИТЕРСКИХ ПАСТ

The article considers the results of the evaluation of consumer preferences in relation to confectionery pastes. The age range of the main cohort of consumers of confectionery pastes has been established - from 16 to 25 years. The periodicity of the frequency of purchase of products is revealed, selection criteria are established, attitude to trademarks. An expert assessment of the organoleptic characteristics of confectionery pastes produced by industrial method was carried out. The physicochemical parameters of industrial confectionery pastes were studied, a distinctive feature was revealed - a high protein content, which provides the studied pastes with competitive advantages in mass and sports nutrition. Recommendations have been developed to improve the consumer properties of confectionery pastes. An alternative raw material source to nuts is proposed: sunflower flour. Functional and technological properties, indicators of oxidative spoilage of heat-treated flour have been studied. A recipe for confectionery paste with an increased content of vitamins C, E, PP is proposed

Detremination of free ammonia in samples of rainbow trout (Onchorynchys mykiss) using «SMARTBIOTIC»

Fish is a product that, under improper storage and transportation conditions, can quickly undergo putrefactive spoilage, therefore, one of the indicators of fish spoilage is the detection of free ammonia in fish samples. The determination of ammonia formed during fish spoilage is based on the fact that it forms a white cloud of ammonium chloride in the presence of hydrochloric acid. According to the intensity, the rate of cloud formation and its stability, the degree of spoilage of fish is judged. the purpose of our study was to determine the effect of the use of the drug "SmartBiotic", produced on the basis of humic acids, on the quality and safety of the fish products obtained, namely, the detection of free ammonia in the selected samples of rainbow trout.Three groups of rainbow trout fingerlings (Oncorhynchus mykiss) were formed to conduct the study. One group served as a control, and the other two were experimental subjects. The first experimental group of fingerlings received the drug at a concentration of 0.15%, and the second experimental group – at a dose of 0.25%. In the control group of rainbow trout, the drug "SmartBiotic" was not used.

Wireless portable bioelectronic nose device for multiplex monitoring toward food freshness/spoilage

Monitoring food freshness/spoilage is important to ensure food quality and safety. Current methods of food quality monitoring are mostly time-consuming and labor intensive processes that require massive analytical equipment. In this study, we developed a portable bioelectronic nose (BE-nose) integrated with trace amine-associated receptor (TAAR) nanodiscs (NDs), allowing food quality monitoring via the detection of food spoilage indicators, including the biogenic amines cadaverine (CV) and putrescine (PT). The olfactory receptors TAAR13c and TAAR13d, which have specific affinities for CV and PT, were produced and successfully reconstituted in ND structures. TAAR13 NDs BE-nose-based side-gated field-effect transistor (SG-FET) system was constructed by utilizing a graphene micropattern (GM) into which two types of olfactory NDs (TAAR13c ND and TAAR13d ND) were introduced, and this system showed ultrahigh sensitivity for a limit of detection (LOD) of 1 fM for CV and PT. Moreover, the binding affinities between the TAAR13 NDs and the indicators were confirmed by a tryptophan fluorescence quenching assay and biosimulations, in which the specific binding site was confirmed. Gas-phase indicators were detected by the TAAR13 NDs BE-nose platform, and the LODs for CV and PT were confirmed to be 26.48 and 7.29 ppb, respectively. In addition, TAAR13 NDs BE-nose was fabricated with commercial gas sensors as a portable platform for the measurement of NH3 and H2S, multiplexed monitoring was achieved with similar performance, and the change ratio of the indicators was observed in a real sample. The integration of commercial gas sensors on a BE-nose enhanced the accuracy and reliability for the quality monitoring of real food samples. These results indicate that the portable TAAR13 NDs BE-nose can be used to monitor CV and PT over a wide range of concentrations, therefore, the electronic nose platform can be utilized for monitoring the freshness/spoilage step in various foods.