Shelf life of irradiated minimally processed (MP) watercress (Nasturtium officinale)

This study was carried out to evaluate the shelf life of minimally processed (MP) watercress exposed to gamma radiation with doses of 1.0; 3.0; 4.0 kGy. Packaged irradiated and non-irradiated MP watercress was subject to sensory analysis. A panel consisting of 25-30 non-trained members, aged 20-55 years, was used. Sensory evaluation was carried out on days 0, 2, 5, 7, 9 and 12 after treatment with packages maintained at 7 °C. The members of the panel rated each sample for overall liking on a hybrid 10 hedonic scale (0 = extremely dislike; 10 = extremely like). Microbiological analyses were also conducted. Compared to the non-irradiated sample, 1 kGy irradiated watercress increased its shelf life by one day (16 days). Shelf lives of samples exposed to higher doses were reduced to 9 days (3 kGy) and 6 days (4 kGy) due to changes in appearance. The microbiological quality was good throughout the experiment.

Stability studies and shelf life estimation of a soy-based dessert

This work is aimed at evaluating the physicochemical, physical, chromatic, microbiological, and sensorial stability of a non-dairy dessert elaborated with soy, guava juice, and oligofructose for 60 days at refrigerated storage as well as to estimate its shelf life time. The titrable acidity, pH, instrumental color, water activity, ascorbic acid, and physical stability were measured. Panelists (n = 50) from the campus community used a hedonic scale to assess the acceptance, purchase intent, creaminess, flavor, taste, acidity, color, and overall appearance of the dessert during 60 days. The data showed that the parameters differed significantly (p < 0.05) from the initial time, and they could be fitted in mathematical equations with coefficient of determination above 71%, aiming to consider them suitable for prediction purposes. Creaminess and acceptance did not differ statistically in the 60-day period; taste, flavor, and acidity kept a suitable hedonic score during storage. Notwithstanding, the sample showed good physical stability against gravity and presented more than 15% of the Brazilian Daily Recommended Value of copper, iron, and ascorbic acid. The product shelf life estimation found was 79 days considering the overall acceptance, acceptance index and purchase intent.

Study of the shelf-life of a mixed araça (Psidium guineensis Sw.) and marolo (Annona crassiflora Mart.) jam

The objective of this study was to add value to araça and marolo fruits by developing jams and verifying changes in their physical, chemical, and microbiological parameters during storage. The analyses were carried out every 2 months. From the results, it was shown that the levels of moisture (35.89 - 26.34%), lipids (0.43 - 0.27%), sucrose (30.62 - 28.98%), total pectin (0.83 - 0.50%), soluble pectin (0.52 - 0.38%), total phenolic compounds (180.31 - 135.52 mg.GAE 100 g-1), and organic acids (401.1 - 68.5 µg.g-1 citric acid) decreased during storage. However, the levels of protein (0.83 - 0.95%), carbohydrate (62.52 - 72.5%, calories (257,11 - 295,931 kcal), fiber (0.72 - 1.4%), total soluble sugar (62.52 - 70.44%), reducing sugar (32.05 - 41.41%), soluble solids (68.4 - 72.18 °Brix), consistency (0.33 - 0.44 N), total antioxidant potential (11.3 - 22.63%), and color (a* 7.56 - 9.49, and b* 8.63 - 10.49) increased during 1-year storage. The quality of the fruit jams studied was in accordance with the microbiological standards established by the Brazilian legislation. It was concluded that the mixed araça and marolo jam can be stored for 1 year without the addition of additives.

Effect of postharvest temperature on the shelf life of gabiroba fruit (Campomanesia pubescens)

The objective of this study was to determine the optimal temperature for storing gabiroba fruit (Campomanesia pubescens) without affecting compounds' quality. The fruits were stored at different temperatures (0 ºC, 6 ºC, 12 ºC, and 20 ºC) and the effect on the pH, total titratable acidity, soluble solids, total sugars, vitamin C, and antioxidant components such as tannins and total phenolic compounds was evaluated. It was observed an increase in the pH and total titratable acidity during storage at all the temperatures tested. Gabiroba fruits were stored for 9 and 3 days at 12 ºC and 20 ºC, respectively, and under both temperatures they showed a reduction in tannins and an increase in vitamin C content. As gabirobas armazenadas a 0º and 6 ºC alcançaram maior tempo de armazenamento After 12 days of storage, the fruits stored at 6 ºC contained higher amounts of water soluble solids, sugars, and antioxidants. In general, for long term storage, it is suggested to store gabiroba fruits at 6 ºC. On the other hand, for short term storage, the temperature of 12 ºC would be the better to keep high levels of vitamin C and phenolic compounds.

Effect of chitosan-carvacrol edible coatings on the quality and shelf life of tilapia (Oreochromis niloticus) fillets stored in ice

Abstract Fish consumption has increased in recent years. However, fish meat is highly perishable, which demonstrates the need for technologies to preserve its quality. Edible coatings (EC) might provide an alternative to extend the shelf life of fish. The goal of this study was to evaluate the effect of EC of chitosan (C) in combination with carvacrol (CAR) on the physical and microbiological changes of tilapia fillets. Fillets were submerged for two minutes in different treatments (T1: control; T2: C 2%; T3: C 2% + 0.125% CAR; T 4: C 2% + 0.25% CAR). At the end of storage, T1 and T2 showed the lowest values of total volatile bases (TVB). The color parameters L*, a* and b* varied from each treatment. The texture decreased and the different treatments reduced the microbial population in relation to the control; T3 and T4 were the most effective. These results show that the use of C with CAR might be an alternative method to preserve the quality and safety of tilapia fillets.

Effects of gutting process on the shelf life of cultured meagre (Argyrosomus regius ASSO, 1801) stored at 4 ± 1 °C

Abstract The aim of this study was to determine chemical, nutritional and microbiological evaluation of whole or gutted meagre stored at 4 ± 1 oC. Whole ungutted (Group A), eviscerated (Group B), beheaded-eviscerated fish (Group C) and fillets (Group D) groups were created for this study. According to fatty acid analysis, it was determined that meagre is rich in PUFA content and the n3/n6 ratio is within the ideal limits. In all 4 groups, obtained from fillets values were the highest in general, quality parameters were found within acceptable limits. Psychrophilic and mesophilic aerobic bacteria counts exceeded the standards for fillet groups on 7th days of storage. According to microbiological analysis, ungutted, beheaded, eviscerated samples were not exceeded limit values on 9th day. In conclusion, whole or gutted (headed and eviscerated) storage of meagre is found to be more advantageous compared to fillets for storage at 4 ± 1 oC.

Quality indicators and shelf life of red octopus (Octopus maya) in chilling storage

Abstract There are no precedents concerning the quality of Octopus maya during chilled storage. This study evaluated the shelf life of the red octopus in chilling storage (4oC) and the correlation of the sensory quality index with microbiological counting and the biochemical indicators (hypoxanthine, histamine and volatile amines). A total of 112 whole raw octopi (average weight of 896 g) were randomly selected from seven batches and exposed to 4°C for 18, 24, 48, 72, 84, 96, and 100 h. The histamine concentration (91.7%), followed by the counts of psychrotrophic bacteria (5.5%) and hypoxanthine (2.2%), were the predictors from the redundancy analysis that better explained the changes taking place during the chilling hours. After 72 h of chilling, the microbial count was determined to be log 4.7 CFU/g, and the octopus samples were classified as B quality (minor sensory quality defects) based on the sensory quality scale. Although the samples were not classified as unacceptable at 100 h of refrigeration by the sensory index, the level of histamine reached the defect action level (5 mg/100 g) as ruled by the International Food Safety Authorities. The shelf life of the red octopus in chilling storage was predicted to be 119 h.