Last Day Of Storage Research Articles

Inhibition of spoilage bacteria on marinated chicken by essential oils under aerobic and vacuum packaging.

"Chicken tawook" is a marinated boneless chicken entrée consumed in the Middle East. The aim of this study was to determine whether bioactive essential oil (EO) components carvacrol (CA), cinnamaldehyde (CI), and thymol (TH) would delay the growth of microorganisms causing tawook spoilage during aerobic (AP) or vacuum (VP) packed storage. The EOs at 1% and 2% were mixed individually with the marinade. The samples (10g of chicken cubes with 1.2g of marinade - with or without EOs) were stored in bags under AP and VP (Geryon® ) for 7 days at 4±1°C and abusive conditions (10±1°C). Two control samples consisting of meat chunks and tawook without EO were used. The microflora numbers were greater at 10°C than at 4°C, and the marinade worked additively with AP against anaerobes, yeast and mold (Y & M) and lactic acid bacteria. It also worked additively with VP against aerobic bacteria recovered as Pseudomonas and the total plate count. EO components were observed to decrease microbial populations by a maximum of 4 to 6 log colony-forming unit (CFU)/g depending on the type of microorganism. The combined mixture of marinade and 2% EO (CA, CI, and TH) resulted in the greatest reductions of all spoilage microorganisms at 10°C under AP on the last day of storage. Overall, VP was more effective (p<0.05) than AP in controlling microorganisms at both 4 and 10°C. This study provides an affordable and natural alternative for extending product life. PRACTICAL APPLICATION: The use of EOs in marinated chicken (tawook) is expected to help producers reduce spoilage and extend shelf-life of the product when stored at refrigeration temperatures. EOs provide a cheaper alternative and are naturally sourced. Vacuum packaging will increase the shelf-life of marinated chicken tawook and facilitate its storage and transportation.

Synergistic effect of polyamine treatment and chitosan coating on postharvest senescence and enzyme activity of bell pepper (Capsicum annuum L.) fruit

• Combination treatment of spermidine (SPD), spermine (SPM) and chitosan (Ch) as coating for extending shelf life of capsicum fruit. • Fruits were treated with coating solutions SPD and SPM @ 0.5, 1.0 and 1.5 mM, then coated with chitosan and stored at 10 ± 1 °C. • The biochemical parameters, enzymatic activities, antioxidant capacity and quality parameters were assessed in capsicum fruit during storage. • Spermine (1.5 mM) and chitosan 1% treatment showed the lowest weight loss and was adjudged best treatment to extend storability of capsicum fruit cv. “Rehana”. This study investigated the effects of treating bell pepper fruit cv. Rehana by dipping with spermidine and spermine (0.5, 1.0 and 1.5 mM) and coating with chitosan (1%) on fruit quality, bio-active compounds, antioxidant enzyme activities, shelf life and senescence related compounds. The fruit were stored at 10 °C and 80–90% RH for 56 days. The results revealed that synergistic treatment of spermine 1.5 mM and chitosan 1% (T7) was most effective for reducing weight loss, electrolyte leakage, maintaining fruit quality and enhancing antioxidant activity over other treatments during storage. The bell pepper fruit of T7 treatment exhibited lowered weight loss by 47.6%, electrolyte leakage by 62.6%, malondialdehyde accumulation by 28.3% while maintaining higher total phenols by 68.8%, total carotenoid by 21.9%, ascorbic acid by 15%, total chlorophyll by 30.4%, catalase activity by 34.3% in comparison to control (T1) on the last day of storage. Other treatments showed intermediate effects. The results suggest potential beneficial influence of synergistic treatment of polyamines, particularly spermine 1.5 mM with chitosan in extending shelf life of bell pepper by about 28 days relative to control with notable preservation of bioactive compounds, antioxidant enzymes and slowing senescence indicators over untreated fruit.

Loss of UHT milk quality: changes in compositional and physicochemical parameters triggered by different storage conditions

The objective of this study was to evaluate some compositional and physicochemical changes that occur during UHT (Ultra-high temperature) milk storage for up to four months. A total of 120 samples of UHT milk were collected from two dairy plants in the state of Minas Gerais, Brazil, and stored under two temperatures (20°C and 30°C) during five periods (0, 30, 60, 90 and 120 days). The experimental design was completely randomized, in a 2x2x5 factorial arrangement, with six replicates per treatment (six batches). Evaluated parameters included fat, total protein, casein, lactose, total solids, solids nonfat (SNF) and milk urea nitrogen (MUN) contents, as well as acidity, density, freezing point and indexes of lipolysis and caseinomacropeptide (CMP). When compared to the Brazilian requirements for UHT milk, the mean values ​​for acidity, fat and SNF contents were in accordance with the standards ​​until the last day of storage. The other parameters are still not covered by the specific UHT milk legislation in Brazil. There was no change of relative density and lactose content also remained constant, except for a decrease at the fourth month. A significant increase, over storage time, in acidity, MUN, lipolysis and CMP indexes occurred. On the other hand, there was a significant decrease in SNF and protein contents. The results showed that there was a gradual loss of quality during UHT milk storage, aggravated by the rise in temperature. These findings demonstrate that UHT milk legislation could be improved by adding parameters such as lipolysis and CMP indexes.

“Evaluation of Shelf Life Extension of Vacuum Packed Sardine Marinade Formulated with Leaves of Tamarind (Tamarindus indica) and Malabar Tamarind (Garcinia gummigutta).”

ABSTRACT A ready-to-cook ‘sardine marinade’ was developed by marinating Sardinella longiceps with two different marinades, i.e., leaves of Tamarindus indica and Garcinia gummigutta as the main ingredients in the marinade along with Capsicum annuum and Cocos nucifera as minor ingredients in marinade. Apart from nutritional benefits, the developed products along with control (raw sardine) stored under vacuum at 3°C for 20 days have markedly controlled microbial proliferation and lipid oxidation, thereby prolonging the shelf life of fish. Fish with T. indica leaves showed significantly lower value for pH, trimethyl amine, total volatile base nitrogen, peroxide value, thiobarbituric acid reactive substances, and total viable count till last day of storage than G. gummigutta and control (p< 0.05). Based on sensory evaluation, a shelf life of 16 days can be ensured for fish stored under vacuum, whereas a shelf life of more than 20 days can be ensured due to the synergistic use of plants and vacuum packaging.

Shelf‐life determination of an egg‐based cake, relating sensory attributes microbiological characteristics and physico‐chemical properties

SummaryThe study of sensory, microbiological and physical–chemical properties are important in local products where the level of inspection and quality control are low. The present study aimed to determine the shelf‐life of an egg‐based moist cake, relating sensory, microbiological and physical–chemical properties. Slices of Cavacas de Resende were collected, stored at two different temperatures (7 and 22 °C) and analysed over time (0, 6 h, 1, 2, 4, 7 and 10 days). Salmonella, Bacillus cereus, Listeria monocytogenes and Escherichia coli, were not detected. On 10 days of storage at 22 °C results were above the allowed limit for Staphylococcus aureus. The counts of mesophiles, moulds and yeasts exceeded the allowed limits in the last days of storage at 22 °C. Most of sensory variables presented a positive and highly significant correlation with freshness, with emphasis to brightness (crust and batter), moist, softness and succulence. Hardness and fracturability (both instrumental) showed a highly significant correlation with sensory freshness. Loss of moisture and mould development were main factors for product quality decrease. Better conservation of the product was achieved at 7 °C with a shelf‐life limit of 7 days. At 22 °C, it is recommended to consume the product in 3 days.

Effect of Orange-Fleshed Sweet Potato Purée and Wheat Flour Blends on β-Carotene, Selected Physicochemical and Microbiological Properties of Bread.

Partial substitution of wheat flour with orange-fleshed sweet potato (OFSP) purée in bread can increase vitamin A intake among consumers. The study investigated the influence of wheat flour substitution with 20–50% of OFSP purée on proximate composition, color, β-carotene, water activity, and microbial keeping quality. The moisture content, crude protein, crude fat, total ash, crude fiber, and carbohydrate in bread ranged from 28.6–32.7%, 9.9–10.6%, 5.0–5.5%, 1.9–3.2%, 1.4–1.8%, and 79.1–80.9%, respectively. β-carotene, total ash, and crude fiber contents in bread, and Hunter color values a*, b*, chroma, and ∆E significantly increased with the addition of OFSP purée. Total viable counts (TVC), yeast, and molds in bread ranged from 2.82–3.64 log10 cfu/g and 1.48–2.16 log10 cfu/g, respectively, on the last day of storage. Water activity, TVC, and fungal counts were low in sweet potato composite bread as compared to white bread. Total β-carotene in OFSP bread ranged from 1.9–5.4 mg/100 g (on dry weight). One hundred grams of bread portion enriched with 40% and 50% OFSP purée provides more than 50% of vitamin A dietary requirements to children aged 4–8 years. Incorporation of up to 50% OFSP purée in wheat flour produces a relatively shelf-stable, nutritious, and health-promoting functional bread.

Inhibition of Several Bacterial Species Isolated from Squid and Shrimp Skewers by Different Natural Edible Compounds.

Seafood is an excellent source of nutrients, essential for a healthy diet, ranging from proteins and fatty acids to vitamins and minerals. Seafood products are highly perishable foods due to their nutritional characteristics and composition. The application of nontoxic, natural, and edible preservatives to extend the shelf-life and inhibit bacterial proliferation of several foods has been a hot topic. Consequently, this work aimed to perform the microbiological characterization of squid and shrimp skewers during their shelf-life (five days) and evaluate the susceptibility of randomly isolated microorganisms to several natural edible compounds so that their application for the preservation and shelf-life extension of the product might be analyzed in the future. The product had considerably high total microorganisms loads of about 5 log CFU/g at day zero and 9 log CFU/g at day five. In addition, high bacterial counts of Pseudomonas spp., Enterobacterales, and lactic acid bacteria (LAB) were found, especially on the last day of storage, being Pseudomonas the dominant genus. However, no Escherichia coli or Listeria monocytogenes were detected on the analyzed samples. One hundred bacterial isolates were randomly selected and identified through 16s rRNA sequencing, resulting in the detection of several Enterobacterales, Pseudomonas spp., and LAB. The antibacterial activity of carvacrol, olive leaf extract, limonene, Citrox®, different chitosans, and ethanolic propolis extracts was evaluated by the agar diffusion method, and the minimum inhibitory concentration was determined only for Citrox® since only this solution could inhibit all the identified isolates. At concentrations higher than or equal to 1.69% (v/v), Citrox® demonstrated bacteriostatic and bactericidal activity to 97% and 3% of the isolates, respectively. To our knowledge, there are no available data about the effectiveness of this commercial product on seafood isolates. Although preliminary, this study showed evidence that Citrox® has the potential to be used as a natural preservative in these seafood products, improving food safety and quality while reducing waste. However, further studies are required, such as developing a Citrox®-based coating and its application on this matrix to validate its antimicrobial effect.

The oxidation status of three types of duck meat (conventional, organic, wild) during refrigerated storage under air and vacuum-packaged atmospheres

ABSTRACT 1. This study evaluated and compared the oxidation status of meat from conventionally-farmed, organic and wild ducks during chilled storage in air or vacuum packaging. In total, 48 carcases from each group of ducks were investigated, and 24 carcases from each type of production were stored under vacuum or in air at 3°C ± 1°C. Sample analyses were conducted after 1, 3, 6 and 9 d of storage. 2. The antioxidant capacity (2,2-diphenyl-1-picrylhydrazyl: DPPH), thiobarbituric acid reactive substances (TBARS) and free fatty acids in the breast, thigh and wing muscles were determined. 3. The antioxidant capacity of meat from conventional ducks was higher than that from organic and wild ducks. The muscles of organic and wild ducks were more susceptible to secondary oxidation (particularly when stored in air) than conventionally-raised birds. The free fatty acid levels in samples of breast and thigh meat from wild ducks on the last day of storage were higher than in conventional and organic ducks. 4. The results showed that the oxidation status of meat from conventional ducks was more stable during refrigerated storage than the meat of organic and wild ducks.

Nutritional and fungal load dynamics of fresh brewers\u2019 grain stored under aerobic conditions

Brewers’ spent grain (BSG) is the amplest by-product of the brewing process. The fresh BSG is currently used as low-cost cattle feed due to its microbiological instability and high perishability. While recent research looked at the effects of storage time and temperature on the characteristics of wet brewers grains (WBG) as ruminant feeds. Three storage temperatures (15, 20, and 25 °C) and periods (2, 4 and 6 days) were arranged in a 3 × 3 factorial design. Surface spoilage was not apparent at 15 °C throughout the storage periods. Deterioration was not also observed at 20 °C until the fourth day of storage where slight mold growth was apparent. Extensive mold growth was detected late in the sixth day at 20 °C and continued manifestations up until the last day of storage at 25 °C. Changes in major nutrients, DM losses, and yeast and mold colony count were significantly affected by the interaction of storage temperatures and durations (P < 0.05). Except for samples stored at 15 °C, nutrients contents decreased concomitantly (exceptions are ADF, lignin, and loss in DM) with prolonged storage times (p < 0.05) and increasing temperatures (p < 0.05). Contrast analysis indicated that it would be safe to store under aerobic storage conditions and feed the WBG for dairy cattle.

Aloe-Based Edible Coating to Maintain Quality of Fresh-Cut Italian Pears (Pyrus communis L.) during Cold Storage

Pear fruits are known for their antioxidant and nutritional characteristics. However, they are very susceptible to rapid decay. Edible coating (EC) represents a good strategy to maintain postharvest quality. The effects of two EC in slowing down the senescence processes in fresh-cut ‘Coscia’ pears were investigated: EC1 (A. vera gel, hydroxypropyl-methylcellulose and pomegranate seeds oil (PSO), EC2 (A. vera gel and hydroxypropyl-methylcellulose). Weight loss, firmness and colour decrease more slowly in both EC-treated than in untreated (CTR) slices; soluble solid content increases faster in CTR, indicating a faster ripening process. The specific investigation of undesired microorganisms did not generate any colony in all analysed samples. Sensory analysis confirmed that the tasters preferred the EC2-treated samples, as they were the only ones that did not show undesirable flavours until the last day of storage.

The effect of ascorbic acid, storage period and packaging material on the formation of volatile N-nitrosamine in sausages.

This study aims to determine the amounts of seven volatile N-nitrosamine (VNA) derivatives which are in the risk group, in processed sausages. It also aimed to investigate the effects of the amount of added ascorbic acid, on the VNA level during the sausage manufacturing processes. For this purpose, meat doughs were prepared with two different levels of ascorbic acid. These meat doughs were put into the production process and packaged in two different packages. Thus, VNA derivatives and their amounts were determined according to production stages (heat treatments), packaging method (vacuum, MAP), storage process (Day 1, 7, 15, 30, 60, 90). As a result, it was found that the sausage product carries risk of VNA formation from the beginning of its production until the last day of storage before consumption for up to 90days.

Changes in Physicochemical Properties of Wild and Cultivated Blackberry during Postharvest Cold Storage

Background: Blackberry is a seasonal harvested fruit that is also very fragile and perish- es quickly. A comparative study was conducted to find out influence of cold storage on physicochemical parameters of wild and cultivated blackberry over a period of 12 days. Methods: The plant materials were composed of the blackberry fruit, including a compound of cultivated blackberry (Rubus spp.), and wild blackberry (Rubus fruticosus L. agg) which were harvested in the North of Morocco. The temperature of the storage of wild and cultivated blackberry was 5 °C for 4, 8, and 12 days, and then transferred to 25 °C for 1 day to simulate transport and commercialization. After that, the physicochemical parameters were analyzed. Statistical analyses were performed using SAS. Results: During 12 days of storage, the pH of samples was decreased from 3.69 to 3.22 for wild blackberry, and from 4.85 to 3.43 for cultivated blackberry. The titratable acidity was increased from 1.61 to 3.28 for wild blackberry, and from 2.07 to 3.25 for cultivated blackberry. Flavonoids also showed a remarkable increase in values from 30 to 70.66 mg QE/100g of wild blackberries and from 25.33 to 60.66 mg QE/100g in cultivated ones between harvest and the last day of storage. The variation in skin color revealed a decrease during storage of L* brightness, a* redness, and yellowness b* for both blackberries. Conclusion: The most suitable storage time of blackberry components during cold storage at 5 °C was 12 days. The temperature at 5 °C preserves the quality of the blackberry for both wild and cultivated ones. However, the wild blackberry was more resistant than cultivated one to cold storage.

Study of the microbial diversity of a panel of Belgian artisanal cheeses associated with challenge studies for Listeria monocytogenes

High throughput sequencing could become a powerful tool in food safety. This study was the first to investigate artisanal cheeses from Belgium (31 batches) using metagenetics, in relation to Listeria monocytogenes growth data acquired during a previous project. Five cheese types were considered, namely unripened acid-curd cheeses, smear- and mold-ripened soft cheeses, and Gouda-type and Saint-Paulin-type cheeses. Each batch was analyzed in triplicate the first and the last days of storage at 8 °C. Globally, 2697 OTUs belonging to 277 genera and to 15 phyla were identified. Lactococcus was dominant in all types, but Streptococcus was co-dominant in smear-ripened soft cheeses and Saint-Paulin-type cheeses. The dominant population was not always associated with added starter cultures. Bacterial richness and diversity were significantly higher in both types of soft cheeses than in other categories, including particular genera like Prevotella, Faecalibacterium and Hafnia-Obesumbacterium in mold-ripened cheeses and Brevibacterium, Brachybacterium, Microbacterium, Bacteroides, Corynebacterium, Marinilactibacillus, Fusobacterium, Halomonas and Psychrobacter in smear-ripened soft cheeses. A strong correlation was observed between no growth of L. monocytogenes in a smear-ripened cheese and the presence of an unknown Fusobacterium (relative abundance around 10%). This in silico correlation should be confirmed by further experiments in vitro and in situ.

Protective Effects of Luteolin and Gallic Acid Against Storage-Induced Oxidative Damage in Whole Blood of Female Wistar Rats

Introduction: Whole blood undergoes oxidative stress that precipitates biochemical changes that can lead to lesions during storage. This study attempts to evaluate the effectiveness of gallic acid and luteolin separately and in their combined state against oxidative damage during blood storage. Materials and Methods: Rats were grouped into control and experimental. Blood collected was stored for 28 days at 4°C. On day 0, 14, and 28, blood was withdrawn to study oxidative stress markers, antioxidant enzymes, and protein oxidation products. Results: Catalase activity reduced in all groups. Thiobarbituric acid reactive substance (TBARS) level increased in control without antioxidants (p < 0.05). Combined antioxidants or when separately added at lower concentrations, significantly reduced the TBARS level. Individual antioxidants at higher concentrations increased TBARS as compared with control (p < 0.05; p < 0.01). Decrease in superoxide dismutase activity observed in control was prevented by the antioxidants. Protein sulfhydryl level was restored and sustained until the last day of storage in groups that received individual antioxidants at both concentrations and the combined form at a lower concentration. Addition of either luteolin or gallic acid and their combined form reduced advanced oxidation protein products formation noticed in the control during storage. Conclusions: Luteolin and gallic acid were beneficial in the area of increased antioxidant capacity, prevention of protein product formation, and maintenance of sulfhydryl level. Their combination also showed a synergistic effect that offered a potential to improve long-term storage of whole blood. The antioxidants could possibly collaborate to be excellent potential blood storage additives providing protection against oxidative damage through their antiradical properties.

Effect of light, food additives and heat on the stability of sorghum 3‐deoxyanthocyanins in model beverages

AbstractThis work aimed to evaluate the stability of sorghum 3‐deoxyanthocyanins (DXA) in model beverages (pH 3.5) elaborated with crude sorghum phenolic extract, containing ascorbic acid and sulphite, under fluorescent light exposure and subjected to heat treatment. There was no significant difference in the DXA degradation during storage under light exposure (24.16%) and absence of light (20.72%). DXA degradation did not differ in the presence of ascorbic acid during storage under light exposure (23.99–25.38%) and absence of light (19.87–21.74%). The addition of sulphite caused an initial bleaching reaction, but as a reversible reaction, the anthocyanin content was higher on the last day of storage compared to the first day. There were no significant differences in total anthocyanin content of all treatments subjected to the heat treatment (80 °C for 5 and 25 min). Thus, crude DXA are very stable under light, additives and heat, and may be useful as natural food colourants.

Development of an active packaging based on polyethylene containing linalool or thymol for mozzarella cheese.

The aim of this research was to evaluate the effect of active polyethylene film (PE) containing linalool and thymol active components on the microbial shelf life of mozzarella cheese. PE films containing different concentrations of linalool or thymol (0%, 1%, 1.5% and 2%) were prepared. The antimicrobial properties of the films were examined, and mozzarella cheese was packed with these active films. The antimicrobial properties of packed samples during 30 days of storage were studied. The obtained results from film tests showed that by increasing the concentration of active agents (linalool and thymol) in PE films, the antimicrobial activities of film samples against Escherichia coli, Staphylococcus aureus, Listeria innocua, and Saccharomyces cervicea were increased. The cheese tests result demonstrated that mozzarella cheese packaging with PE films containing different concentrations of linalool and thymol leads to a decreased growth rate of molds and yeasts in cheeses. At the end of the storage period, the lowest number of molds and yeasts was for a sample packed in PE film containing 2% thymol, which increased from 1.00 to 1.21 Log CFU/g during the storage period. From E. coli and S. aureus contamination, the samples packed in active films were safe until the last day of storage (30th day), while the control sample was unacceptable at 17th day of storage. According to obtained results from this study, it was concluded that the addition of linalool and thymol active components to PE film had a positive effect on the extension of the mozzarella scheese shelf life.

Desenvolvimento de requeijão com extrato aquoso de semente de Moringa oleifera

Neste estudo o queijo fundido foi produzido com substituição total e parcial da goma xantana pelo extrato da semente de Moringa e armazenado a 4ºC. Foram estudados a composição química pH, acidez, cor, textura e reologia. A composição química diferiu significativamente (p &lt;0,05) entre as amostras. O teor de proteína foi maior para a amostra contendo apenas extrato de Moringa. A acidez diferiu significativamente (p &lt;0,05) apenas no último dia de armazenamento. Os valores de pH permaneceram dentro dos limites de qualidade estabelecidos (pH ≥ 6,0) para todas as amostras durante os 21 dias de armazenamento. A adição do extrato afetou a cor e a microestrutura das amostras; Queijos processados ​​com extrato adicionado apresentaram partículas de menor tamanho de glóbulos de gordura e distribuídos sem uniformidade. O extrato de Moringa interferiu na textura do produto, revelando-se um grande substituto parcial e / ou total dos conservantes químicos. A amostra com maior substituição de goma pelo extrato de Moringa teve dureza igual à amostra controle. Além disso, esta amostra (T4 - 0,15% goma e 0,35% extrato de Moringa) apresentou maior índice de consistência (K). As amostras não apresentaram diferenças significativas durante o período de armazenamento para coesividade. O perfil reológico mostrou que todas as amostras apresentaram um perfil não newtoniano (pseudoplástico). Dessa forma, acredita-se que a semente da Moringa tenha potencial para uso como substituto de espessante.

Effect of oregano essential oil or lactic acid treatments combined with air and modified atmosphere packaging on the quality and storage properties of chicken breast meat

This study explored the preservative effects of oregano essential oil (0.2% w/w) or lactic acid (1.25% v/v) combined with oxygen permeable (OP) and modified atmosphere packaging (MAP) on meat quality of chicken meat. The samples were stored at 4 °C for 1, 4, 8, and 12 days and examined for pH, color, aerobic plate count (APC), lipid oxidation (TBARS) and sensory analysis. Results indicated that lactic acid treatment under both packaging conditions presented lower pH accompanied with higher color CIE L* (lightness) values throughout the storage period. Color CIE a* (redness) was higher in OP packaging, and CIE b* (yellowness) was lower in the lactic acid treatment till the last day of storage. Samples treated with lactic acid under MAP packaging presented lower APC at 1, 8 and 12 days of storage. The TBARS values were unaffected by packaging methods, however, these were higher in the control group followed by lactic acid and oregano oil treatments. Furthermore, lactic acid was proved the best to preserve the odor and taste of chicken meat. In conclusion, lactic acid treatment under modified packaging can maintain the storage properties of chicken meat without affecting its sensory characteristics during refrigerated storage.

Antioxidant and antimicrobial potency of Eupatorium inulifolium leaf extract for fish preservation

Fish is generally known as a perishable product. This study aimed to investigate the antioxidant and antimicrobial potency of Eupatorium inulifolium leaf extract for fish preservation. The effect of different levels of the leaf extracts (0.1%, 0.25%, 0.5%) on the pH value, aw, Total Volatile Bases (TVB), Total Plate Count (TPC), and texture of tongkol fish (Euthynnus Affinis) during 4 days cold-storage was studied. The results showed that after 4 days of storage, the level of TVB was found at 28,745 mg/100 g in the control sample and 16,022 mg/100 g in the sample of fish with 0.5% of Eupatorium inulifolium leaf extract. On the last day of storage, the lowest number of microbe was found at 10.100 CFU/g in a sample of fish with 0.5% of Eupatorium inulifolium leaf extract while the highest number of microbe was 53,500 CFU/g in the control sample. The addition Eupatorium inulifolium leaf extract resulted in a harder texture. On the contrary, the Eupatorium inulifolium leaf extract addition had no significant effect on the aw value of the fish during storage. This study provided a new perspective of using Eupatorium inulifolium leaf extract for a natural preservative for fish.

The combined impact of calcium lactate with cysteine pretreatment and perforation-mediated modified atmosphere packaging on quality preservation of fresh-cut 'Romaine' lettuce.

The effect of perforation-mediated modified atmosphere packaging (PM-MAP) in combination with calcium lactate (1.5% CaL) and cysteine (0.1, 0.5% Cys) immersion pretreatments on the quality preservation of fresh-cut 'Romaine' lettuce was assessed for 12 days, at 5 and 10 °C. The shredded lettuce was packed in low-density polyethylene films (LDPE, 62µm thickness), including different perforation numbers of 0 (N-MAP), 20 (20-PM-MAP, Diameter = 64µm), and 40 (40-PM-MAP, Diameter = 64µm)per in square meter. Indices of quality maintenance were investigated. The total microbial counts were below the specified limits for ready-to-eat vegetables (< 6 log CFU/g) considering both pretreated 20-PM-MAP and N-MAP samples on day 12. After 8 days, a significant difference (P <0.05) was observed in the browning index (BI), the total color difference (ΔE), and the chlorophyll content between N-MAP and 20-PM-MAP samples with better results in 20-PM-MA packages. At 10 °C, the BI in pretreated 20-PM-MAP samples was 32.44% to 58.35% less than N-MAP samples, on the last day of storage. The 20-PM-MAP samples pretreated with 1.5% CaL/0.5% Cys had the highest (P <0.05) crispness coefficient and water content values. It seems that packaging the pretreated lettuce in 20-PM-MA packages is more effective for maintaining the visual properties (green fresh appearance) of this product, from the 8th to the 12th day of storage. PRACTICAL APPLICATION: The medium to high respiration rate of fresh-cut lettuce causes O2 level drops below its tolerance limit (<1% to 3%) inside the modified atmosphere packaging (MAP). It results in severe browning, off-odors, off-flavor, and growth of anaerobiosis. Perforated-mediated modified atmosphere packaging (PM-MAP) technology can be introduced as an alternative to a nonperforated MAP system (conventional MAP) for fresh-cut lettuce. The application of the PM-MAP system in combination with calcium lactate and cysteine immersion pretreatment (CaL/Cys) may lead to better maintenance of the physicochemical properties of this product.