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Tender jackfruit is quite popular for culinary preparations. Technologies and value-added products of matured and ripened jackfruit are in the commercial domain, but there is a high demand to work on the processing and value addition of tender jackfruit. Especially, interventions are required for the mechanization of different post-harvest operations and to develop process protocols. Minimal processing of tender jackfruit has immense commercial potential as it can make handling easy and reduce transportation costs. Controlling the browning of cut tender jackfruit is a challenge and requires research interventions to develop a safe process protocol minimizing or avoiding the use of chemicals. Tender jackfruit powder, also called flour, is a novel product being invented to explore its possible applications in different food products. However, scientific interventions are required to develop a process protocol for tender jackfruit powder production along with the development of machines for operations like shredding and grinding. Conventional grinding operations lead to nutritional loss of jackfruit powder; hence, there is a great opportunity to develop a low-temperature grinding system for the production of quality powder. The available literature, particularly on tender jackfruit processing, has been summarized in the present paper with its critical analysis and future prospects. [ABSTRACT FROM AUTHOR]

The main obstacle to the commercial marketing of minimally processed apples is related to their greater susceptibility to tissue softening, enzymatic browning, and microbiological development. The primary objective of this study was to investigate the influence of modified atmosphere packaging on enzymatic browning and quality deterioration in fresh-cut 'Royal Delicious' apples. Apple wedges were stored for up to 42 days at 5 ± 2 °C in modified atmosphere packaging with 1.5–5% O2 and 2.5–7.5% CO2. Flesh colour, head space gas composition, titratable acidity, soluble solids content, ascorbic acid content and overall sensory quality of apple slices were evaluated during storage. At the end of the storage period, the titratable acidity of apple wedges packed under modified atmospheres ranged from 0.56% to 0.18% for all treatments. Apple wedges packaged under 5% O2 and 5% CO2 had the highest titratable acidity (0.49%) by the end of storage. After 42 days of storage, total soluble solids content in apple wedges was highest for wedges packaged under 1.5% O2 and 7.5% CO2 (15.9%) and lowest in control (9.7%). Enzymatic browning was suppressed and overall quality of the apple wedges was retained under modified atmospheres. Overall, the modified atmosphere packaging proved to be the most effective treatment to preserve the nutritional and sensory attributes of apple wedges for 42 days of storage. [ABSTRACT FROM AUTHOR]

Onions are always in high demand owing to various culinary as well as health protective properties and these days there is increased consumer preference for ready-to-eat or ready-to-cook onions. In this context, the current study was aimed to extend the keeping quality of minimally processed onions for an extended period while ensuring microbial safety as well as sprouting inhibition through an integrated approach. The optimized combinatorial approach included gamma radiation treatment (Dmin60 Gy), minimal processing (de-skinning and scooping) and packaging in trays wrapped with polypropylene (PP; 10 µm thick) film followed by storage at low temperature (4–6 °C, relative humidity RH 65–70%). The parameters like shelf life, physico-chemical (colorimetry, moisture), organoleptic and nutritional properties were comprehensively assessed and found to be well retained up to 30 days with moisture loss of ≤ 5% and overall acceptability rating of 7 on 9-point hedonic scale. Microbiological analyses confirmed absence of Salmonella spp in these stored onions thus ensuring microbial safety. Nutritional profiling including carbohydrate, protein, fat, energy, and ash content revealed no significant change due to the processing as well as during storage. Thus, the radiation processing of freshly harvested bulbs followed by minimal processing, packing in formulated package and storage under low temperature conditions were found acceptable up to 30 days in the ready-to-eat form. Current findings provide credible evidences ascertaining extended shelf-life as well ensuring microbial safety of processed onions for commercial utilization by the food industries. [ABSTRACT FROM AUTHOR]

High pressure processing of pineapple has potential implication in food industry. The impact of high pressure (HP) processing and minimal processing, on quality parameters of pineapple was analysed. Changes in the pineapple quality in terms of texture, colour, total flavonoids, total polyphenols, vitamin C and sensory properties were investigated within the domain of 100–300 MPa and 5–20 min. Quality changes induced by HP processing was compared with the minimally processed pineapple. High pressure processing significantly (p < 0.0001) affect the firmness, total flavonoids, total polyphenols, vitamin C and colour values and were significantly increased in HP processed samples, while in minimal processed samples, these quality attributes exhibited a major degradation. On the basis of quality analysis, microbial quality and sensory assessment, high pressure treatment at 300 MPa for 10 min was found to be suitable for preserving the quality of pineapple up to 16th day in refrigeration condition. [ABSTRACT FROM AUTHOR]

The effect of a UV-C (0, 2.4, 4.8 and 7.2 kJ m−2) pre-treatment was studied during storage at 5 °C on quality changes of fresh-cut watermelon cylinders with different cut intensities (2.7 cm Ø; 1, 2, 4 or 8 cm length). The steady state of the modified atmosphere was reached on day 4 with 4.5–9.6 kPa CO2 + 14 kPa O2. UV-C treatments were more effective against enterobacteria since enterobacteria counts were better preserved during storage in 4 and 8 cm cylinders under 7.2 kJ m−2. The longest shelf life (7 days), based on sensory quality, was established for the biggest cylinders (8 cm) treated with 4.8 kJ m−2, while it was reduced to 5 days for the remaining UV-C doses, regardless of the cut intensity. Lycopene content (52.1–75.3 mg kg−1) was not affected by radiation treatments. After UV-C illumination, initial total phenolic contents (387–508 mg kg−1) were reduced, reporting less reductions for higher cut intensities. Initial total antioxidant capacity (1.32–2.44 mmol kg−1), mainly due to phenolic compounds and lycopene, was decreased after UV-C treatments. Total antioxidant capacity of UV-C samples was increased (2- to 14-fold) compared with untreated samples throughout storage as an antioxidant response of UV-stressed samples. Conclusively, fresh-cut watermelon cylinders of 8 cm length (2.7 cm Ø) better preserved their quality during storage compared with smaller cylinders, with a shelf life of 7 days when a 4.8-kJ m−2 UV-C dose was applied. [ABSTRACT FROM AUTHOR]

Modern city lifestyle is characterized by an increased demand for fresh or minimally processed foods. Lettuce (Lactuca sativa L.), mainly iceberg lettuce, is the main vegetable used during the manufacture of fresh-cut salads. The current study evaluated the phenolic content and antioxidant activity of ten fresh and minimally processed lettuce varieties. The phenolic content of selected lettuce samples varied significantly among varieties. Although a higher phenolic content was observed in modern lettuce varieties, when compared to the traditional ones (except for the landrace Francès 219/855), the antioxidant capacity of modern and traditional lettuce varieties was similar. Minimal processing followed by storage for a 7-day period led to an increased phenolic content in varieties Rutilaï RZ, Abago RZ, Maravilla LS044, Francès 219/855, Negre borratger 386/935, and D'hivern LS008, supporting the hypothesis that wounding can induce the accumulation of phenolic compounds in lettuce leaves. For example, the total phenolic content of Francès 219/855 after processing and storage increased from 8.3 to 11.3 mg/100 g (p < 0.05). Accumulation of phenolic compounds after minimal processing was not observed in all the studied samples, suggesting that this effect could be matrix-dependant. The amount of bioaccessible polyphenols was higher after minimal processing and storage. Indeed, the amount of bioaccessible polyphenols after a simulated gastrointestinal digestion of fresh or minimally processed Pelikan lettuce was calculated as 32.6 or 43.3 mg/100 g respectively (p < 0.05), suggesting that the increased amount of polyphenols caused by processing and storage can also lead to a higher amount of bioaccessible phenolic compounds. [ABSTRACT FROM AUTHOR]

The whiteness of shredded carrots is generally caused by enzymatic reactions after removal of natural protection during the minimal processing. Moreover, the use of chlorinated solution in sanitizing step of processing, promotes the formation of halogenated by-products, with correlated environmental and health risks in processing areas. This study investigated the effect of different acidic solutions on the quality of shredded carrots during the storage at two refrigerated temperatures (4 °C and 7 °C), as alternative agents to chlorine in food industry. Carrots dipped in 1.5% citric acid solution did not present colour variation at both storage temperatures. Moreover they showed the lowest microbial charge after processing and during storage at 4 °C. Carrots dipped in 0.5% citric acid + 0.05% ascorbic acid + 0.05% calcium chloride evidenced lower PAL and POD activities during the storage respect to the other tested samples. Therefore, the dipping of shredded carrots in acidic solutions, as alternative sanitizers to chlorine, contributed to preserve their quality, also controlling the whiteness index of carrots' surface. In particular, the dipping in 1.5% citric acid extended the shelf life of shredded carrots up to 14 days of storage at 4 °C. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the shelf life of arils and the changes in their biochemical compounds in nineteen Iranian pomegranate cultivars during storage. Fruits were harvested when commercially mature and the arils were removed, packaged and stored at 5 ± 1 °C, at 85-90% relative humidity in a cold room. Samples of the stored arils were examined for biochemical features in temporal checkpoints throughout a storage period that lasted for 35 days. By using the onset of decay as an index, the shelf life of arils varied among cultivars, ranging from 7 days to approximately 21 days. Considering the quality attributes of ready-to-eat arils at the beginning of the experiment, substantial variations were observed among the cultivars with regard to their titratable acidity (0.50-8.47%), total soluble solids (13-18.66 °Brix), DPPH radical scavenging activity (63-87.44%), Gallic-acid-equivalent (2.64-6.95 mg/ml) and ascorbic acid (12.21-75.09 mg/l). In general, the decay of arils gradually increased during storage, but several cultivars—which exhibited a very slow process of decay—contained the highest content of titratable acidity, Gallic-acid-equivalent and total soluble solids (since the signs of decay appeared on around the twenty-first day of storage). In addition, titratable acidity increased slightly by the end of storage, whereas the ascorbic acid content, total soluble solids and Gallic-acid-equivalent were cultivar-dependent and did not show consistent patterns of change during storage. [ABSTRACT FROM AUTHOR]

Nowadays, consumers demand healthy, safe, and ready-to-eat horticultural products because of their lifestyle. In this regard, new legume-based food product development with eco-innovative technologies seems to be an interesting market. The effect on quality of an innovative pesto sauce, made of fresh faba bean seeds, of an alternative continuous microwave treatment pasteurization (MW, 11 kW; 30 s) regarding a conventional pasteurization (85 °C; 5 min) throughout 20 days at 5 °C was studied. Non-heated blended samples were used as control. The microbial quality was satisfactory in all treatments. MW treatment improved the sensorial quality of pesto sauce and decreased condensed tannins. Additionally, MW-treated samples showed the best texture, consistency, and color, preserving its chlorophyll and carotenoid content. On the other hand, thermal treatments showed a decrease in total phenolic compounds (TPC) and antioxidant capacity (TEAC) after heating, regarding control samples; however, TPC and TEAC remained quite constant throughout the storage. [ABSTRACT FROM AUTHOR]

Storing fresh-cut apple slices in suitable fruit juice or sugar syrup is a general practice. However, application of this approach is mainly based on empirical knowledge, while systematic and comprehensive analyses of the relevant effects of this storage technique on keeping quality-related physiological properties of fresh-cut products is still missing. Hence, the aim of this study was to evaluate the impacts of complete immersion of fresh-cut apples in sugar syrup and fruit juice solution on respiratory behaviour and other relevant quality attributes (colour, tissue strength, and soluble solid and acidity). Sugar syrup and pure orange juice showed a high potential to store and protect fresh-cut apples. Results showed that only pure orange juice positively affected the produce quality by preventing browning effects. In addition, sugar syrup of 13.4-20% most effectively prevented browning of apple slices and guaranteed high product quality retention during storage. The application of different liquid media provides a practical means to prevent browning and maintain product quality. [ABSTRACT FROM AUTHOR]

Texture and mesostructure of packaged fresh-cut 'Fuji' apple slices were studied during 30 days storage at 4, 10 and 20 °C. Instrumental mechanical-acoustic texture evaluations were carried out, and cell wall materials were isolated from the flesh tissue by means of an ethanol and methanol-chloroform solvents extraction procedure. The emphasis was on relating the macroscopic loss of fresh texture characteristics to the changes in the rheological properties occurring to the structuring elements of the cell wall materials (CWMs). The rheology of the reconstituted CWM water dispersion was evaluated by means of oscillatory dynamic testing, and viscoelastic data were interpreted according to the 'weak-gel model' theory. The dynamics of the flowing components at the mesoscale structural level was related to the texture softening, which yields decrease in firmness and rigidity parameters, and an attenuation of the acoustic emission (fewer acoustic peaks and lower sound pressure level), as it was measured in the combined acoustic-mechanical test. The kinetic reaction rate values are presented. Softening of apple flesh is accompanied by slight cleavage of molecular assemblies and a loss in cell adhesion, mediated by the increase in assemblies' water uptake. The ability to handle the relationship between the sounds produced during flesh crushing and the structure of the cellular tissue would assist breeders and geneticists in the selection and control of the apple crispness, or would support technologists in preventing postharvest softening during storage and retail. [ABSTRACT FROM AUTHOR]

Gamma irradiation (0.5-2.5 kGy) in combination with low temperature (4-15 °C) storage was attempted to increase shelf life of ready-to-cook shredded cabbage wrapped in cling films. A maximum extension in shelf life of 8 days, while retaining the microbial and sensory quality, was obtained with an irradiation dose of 2 kGy and storage at 10 °C. Gamma irradiation also inhibited browning of shredded cabbage at their cut edges resulting in enhanced visual appeal. An increase in total antioxidant activity was observed with respect to DPPH and hydroxyl radical scavenging ability while the nitric oxide radical scavenging activity and ferric reducing property remained unaffected with irradiation. Total phenolic, flavonoid and vitamin C content remained unchanged due to irradiation. No significant migration of additives from cling films into stimulant water was observed up to a radiation dose of 2 kGy thus demonstrating the feasibility of such films for above applications. [ABSTRACT FROM AUTHOR]

Little information is available regarding the incorporation of dietary fiber into edible films and coatings. In this work, apple fiber and inulin were incorporated into polysaccharide-based (alginate, pectine and gellan gum) edible coating formulations and their effects on the quality attributes of fresh-cut apples were evaluated. Antioxidant properties, color, firmness, sensory quality and microbial growth of fresh-cut apple were studied during 16 days of storage at 4 °C. Results show that dietary fiber extracts incorporated to gellan gum, pectin and alginate-based coatings together with calcium chloride and ascorbic acid successfully maintained the firmness and color of coated fresh-cut apples in comparison with uncoated control samples, which presented severe texture softening and browning. The firmness of apple pieces coated with polysaccharide-based coating formulations incorporating apple fiber doubled, and sometimes tripled, that of uncoated samples. Any of the assayed coatings exhibited a positive effect on the sensory properties of fresh-cut apples. The incorporation of apple fiber, together with the use of ascorbic acid, contributed to keep the antioxidant potential of the fruit at least during the first week of storage. Furthermore, gellan gum coatings had a marked effect in reducing mesophilic and psychrophilic counts on fresh-cut apples throughout storage regardless the addition of dietary fibers. The results achieved demonstrate the feasibility of the addition of dietary fiber to edible coating formulations for increasing the nutritional value of fresh-cut apples without compromising their fresh-like quality attributes. [ABSTRACT FROM AUTHOR]

Present study was aimed at understanding the effect of pretreatments and modified atmosphere packaging on the quality of fresh-cut green bell pepper (Capsicum annuum L.) during low temperature storage. Dip treatment of freshly cut green bell pepper pieces in 2 % calcium propionate followed by surface drying and subsequent packing in cryovac PD961 film which maintained an equilibrium modified atmosphere of 13-14 % O2 and 7 % CO2 helped to extend the marketability till 9 days storage at 8 °C. The microbiological quality was at the best level up to 6 days of storage, as evidenced by a surge in aerobic plate count, pectinolysers and pseudomonads on subsequent days. Head space volatile analysis of the produce at regular intervals showed a reduction in monoterpenoids and simultaneous increase of aldehydes and ketones, sesquiterpenoids, esters, furans and pyrazines during storage. Principal component analysis of the head space volatiles identified, cis - ocimene, 1,3,8-paramenthatriene, trans 3- caren 2-ol, bergamotene, 2-hexenal, ethyl 1- decanol, (E)-3- hexenol and heptane thiol as the markers of freshness in minimally processed green bell pepper. [ABSTRACT FROM AUTHOR]

Degree of browning, firmness, sensory properties and microbiological quality of minimally processed immature jakfruit were investigated on initial and seventh day after storage at 5-7 °C. Samples were pretreated with 0.5 % and 1 % sodium metabisulphite, 1.5 % citric acid + 1.5 % ascorbic acid, 3 % citric acid, 3 % ascorbic acid and packed in polystyrene packages and over wrapped with polyvinylchloride (PVC) stretch film before storage. When degree of browning in relation to absorbance was assessed, immature jakfruit pretreated with 1.5 % citric acid + 1.5 % ascorbic acid showed the lowest absorbance at 420 nm among all pretreated samples indicating low browning in samples. At 450 nm, minimally processed immature jackfruit samples pretreated with 1.5 % citric acid + 1.5 % ascorbic acid showed the highest reflectance (indicating lowest absorbance) compared to other treatments. Variations in firmness were observed after treatment. Microbial counts were within safe-to-consume limits while coliforms were not detected in any of the samples. Erwinia aphidicola and Bacillus subtilis were identified from minimally processed immature jakfruit samples using molecular tools. 1.5 % citric acid + 1.5 % ascorbic acid, 1 % sodium metabisulphite and 3 % citric acid were relatively more successful in retaining acceptable sensory quality of jakfruit even after 7 days of storage. Above pretreatments could be recommended during minimal processing of immature jakfruit meant for local sale in supermarkets where cold storage is available. [ABSTRACT FROM AUTHOR]

To control enzymatic browning in minimally processed yacon ( Smallanthus sonchifolius), strategies combining anti-browning agents and modified atmosphere were investigated. Yacon slices were immersed in anti-browning agent solutions-sodium metabisulfite (0.5 %), L-cysteine (0.5 %), or the acids lactic (1 %), malic (1 %), succinic (1 %), ethylenediaminetetraacetic (EDTA; 1 %), ascorbic (3 %), citric (3 %) or tartaric (3 %), or a control (0.5 % de sugar)-for 5 min, then packaged with air or modified atmosphere (N) and stored at 5 °C. Sensory and physical-chemical (soluble solids, phenolic content, peroxidase activity, pH, color, instrumental texture, and mass variation) analyses were performed. For a given anti-browning agent, any significant difference was not found between yacon slices stored under air or N. However, when comparing the different anti-browning agents, only ascorbic, citric, and tartaric acids were effective enzymatic browning inhibitors without significantly changing typical sensory attributes of yacon. Among them, tartaric acid is not often reported in literature for controlling enzymatic browning in vegetal products, contrarily to the two others. [ABSTRACT FROM AUTHOR]

In the industry of fresh-cut potatoes, controlling browning and delaying the loss of texture are important factors to obtain a high-quality product. The use of ultrasound can avoid these undesirable phenomena due to its power to inactivate enzymes by breaking the cell membranes because the cavitation activities and formation of free radicals. For this purpose, this study aimed to evaluate the effect of different times of contact of ultrasound (40 kHz, 200 W for 1, 5 and 10 min) on quality parameters (browning, firmness and total starch content) of fresh-cut potatoes during the product shelf life (12 days; 3 ± 1 °C) and cell microstructure. Ultrasound was applied to asterix strips (rectangular, 10 × 10 mm). Results showed that the time of sonication and storage affected significantly to the pH of the samples. Treated samples for 5 and 10 min presented the lower values of pH. No color degradation was noticed immediately after the application of treatments (Hue and Chroma). However, a slight decrease in Hue angle of fresh-cut potatoes during storage has been observed. The use of 5 min of sonication inhibited 50 % of polyphenol oxidase (PPO) activity for the first 4 days of storage. Samples submitted to 5 and 10 min of ultrasound also had maintained more uniform firmness after frying during storage time. However, the longest time of immersion (10 min) caused damage in the potato cells. [ABSTRACT FROM AUTHOR]

Virulent bacteriophages (VP) and high hydrostatic pressure (HHP) were studied for the inactivation of Shigella flexneri in ground beef and Vibrio cholerae in salmon and mussels. Inoculated foods were treated individually with HHP (150-450 MPa for 5 and 9 min, 300 MPa for 13 min, and 550 MPa for 5 min), with phages (cocktail of 3 S. flexneri or single V. cholerae phages, both applied at 10 PFU/mL) or combinations thereof (HHP/VP, VP/HHP). Stand-alone treatments with VP, HHP below 450 MPa (seafood) or 550 MPa (meat), and combined treatments of VP and HHP at 250 MPa for 5 min did not reduce bacterial counts below the detection limit. By contrast, complete inactivation of S. flexneri and V. cholerae ( P < 0.05) was achieved at 550 MPa for 5 min or, more energy-efficient, at 350 MPa for 5 min followed by addition of phages, thus, indicating a combination of HHP and VP as an efficacious hurdle technology for meat and seafood processing. [ABSTRACT FROM AUTHOR]

In this study, the quality of minimally processed different Iranian pomegranate genotypes was investigated during storage at 4 °C for 14 days. The results showed that at the end of storage time, the lowest microbial count was found on the arils of 'Torsh Syabe Lorestan' genotype. There was a significant difference in titratable acidity, total soluble solids, total anthocyanin, catechin, and quercetin content in most genotypes after 14-day cold storage; while no difference was found between studied genotypes in antioxidant capacity, total phenolic, and flavonoid content. In general, total phenolic content and antioxidant capacity of pomegranate arils gradually decreased over storage time. Diphenolase activity of polyphenol oxidase (PPO) enzyme with dopamine hydrochloride substrate and peroxidase (POD) decreased over storage time, whereas diphenolase activity of PPO with pyrocatechol substrate significantly increased. The lowest diphenolase activity with dopamine hydrochloride and pyrocatechol substrates, as well as POD activity was found in Torsh Syabe Lorestan. The results suggested that the genotype of Torsh Syabe Lorestan, which showed the lowest microbial count on the arils and enzymes, could be more appropriate for minimal processing technology. [ABSTRACT FROM AUTHOR]

Inactivation of pectin methyl esterase was evaluated using thermal and ohmic treatments. Kinetics of enzyme inactivation in crude extracts during thermal treatment was described by a first order model yielding an activation energy of 202.52±25.86 kJ/mol. Pectin methylesterase was inactivated more rapidly by an ohmic treatment than by heating. A gradient of 25 V/cm was used to evaluate ohmic induced changes in color, reducing sugar concentrations, mineral and total polyphenolic contents, and rheological and morphological properties. A pseudo-plastic behavior was observed and the Power law was considered adequate to describe apple puree behavior. Minimal changes in physico-chemical parameters occurred. Ohmic treatment can be used in food processing and bioengineering for inactivation of quality-degrading enzymes and retention of health-related compounds and extension of the shelf-life. [ABSTRACT FROM AUTHOR]

Papaya cubes at maturity stages, 5-45 % yellow (more green than yellow) and 55-80 % yellow (more yellow than green) were washed with 5 % HO, drained and packaged in PVC trays having five, seven and ten micro-perforations and stored for 19 days. PVC trays with 3 mm diameter punch holes were used as the control. Based on physico-chemical properties, optimum maturity for papaya and micro-perforation level of PVC trays were determined. Effectiveness of citric acid in prevention of browning was also tested. Firmness and TSS changed significantly, on day 19. O, CO and CH concentration changed 2.4 to 4.2 %, 23.4 to 5.9 %, and 0 to 0.13 % respectively, from day 3 to 19. pH and titratable acidity did not change significantly throughout the storage. Pretreated papaya cubes, packaged in PVC trays with ten micro-perforations, kept under 4 °C had storage lives of 19 days. [ABSTRACT FROM AUTHOR]

Jackfruit ( Artocarpus heterophyllus L.) bulbs were minimally processed using variables such as CaCl concentration (0.13-1.47%), ascorbic acid (AA) concentration (0.005-0.03%), and treatment time (8-43 min). Second-order polynomial model was proposed with regard to effect of independent variables on responses such as juice leakage, firmness, browning index, L value, and overall acceptability by response surface methodology (RSM) using a central-composite experimental design. The established models for responses showed a good fit with the experimental data ( R > 0.896), describing the effect of independent variables on the quality parameters of minimally processed jackfruit bulbs. The recommended processing conditions for maximizing firmness, L value and overall acceptability and minimizing juice leakage, and browning index in the samples at the end of 20 days of low temperature storage were found to be 1% CaCl, 0.02% AA, and 30 min of treatment time. The RSM was found to be an effective tool to model the effect of minimal processing treatments on jackfruit bulbs quality. [ABSTRACT FROM AUTHOR]

Edible coatings can represent an alternative for extending post-harvest life of perishable fruits, as strawberries. In this work, the effect of cassava starch edible coatings, added or not of potassium sorbate, on mechanical properties, surface color, sensory acceptance, and respiration rate of strawberries was evaluated in order to choose the best coating conditions to minimally processed strawberries. Integrity and water-vapor resistance of the coatings were also evaluated. Three different concentrations of cassava starch (1%, 2%, and 3%) and two concentrations of potassium sorbate (0.05% and 0.10%) were used in the coatings formulations. Minimally processed strawberries without coating were used as control samples. The strawberries treated with different coatings and control fruits did not present differences regarding mechanical properties, surface color, and all the sensory attributes evaluated. A good integrity of cassava edible coatings on strawberries surface was observed for 2% and 3% starch concentration and the use of coatings, in these concentrations, reduced the strawberries respiration rate, representing a possibility to extend the shelf life of fruits. All coatings showed beneficial effects on increasing the water vapor resistance of the samples, but a significant increase was obtained only with the use of coating with 3% of starch. The potassium sorbate improved significantly the resistance to water vapor, but no differences were observed between the two concentrations studied. Based these results, the coatings with 3% of cassava starch and 3% of cassava starch +0.05% of potassium sorbate were those selected for future shelf life study of minimally processed strawberries. [ABSTRACT FROM AUTHOR]

Minimally processed vegetables in fresh, ready-to-cook form are gaining the confidence of both the trader and the consumer. This has led to a need to develop technology for increasing shelf life while maintaining the microbial, nutritional and sensory quality of minimally processed vegetables. This investigation was carried out on pumpkin in minimally processed form, packed in different polymeric film bags of varying permeabilities, creating an active equilibrium modified atmosphere within the package for the extention of storage life. It was observed that minimally processed pumpkin, which has a high respiratory rate at room temperature (155.7 mg CO2/kg/h) could be stored for a period of 25 days at 5±2 °C under modified atmosphere packaging conditions with a minimum physiological loss in weight of 0.06% and marginally low changes in biochemical constituents, such as vitamin C, total soluble solids, moisture, carotenoids and titrable acidity, enabling the retention of near-fresh quality. The microbial loads of mesophilic aerobes and coliforms, which were log 5.5 and log 4.3 were less than threshold level. There was no growth of yeasts and moulds or mesophilic spore formers at the end of the storage period. [ABSTRACT FROM AUTHOR]

The effect of modified-atmosphere packaging (MAP) on the amount of soluble phenolics in, and the visual appearance of, white, green and red tissues of minimally processed “Lollo Rosso” lettuce were evaluated. Minimal processing induced a two-fold increase in the amount of soluble phenylpropanoids in the midribs during storage in air at 5°C. When the lettuce was stored in the presence of 2–3% O2 and 12–14% CO2, this increase was not induced and no browning was observed. A particularly marked decrease in the amount of phenylpropanoids was observed in MAP-stored green and red tissues. The concentrations of flavonoids and anthocyanins did not change much in midribs and green tissues, while they were significantly degraded in red tissues under MAP conditions. MAP storage proved useful in the prevention of browning, the main cause of quality loss in minimally processed “Lollo Rosso” lettuce. However, MAP storage was not so beneficial for the preservation of the quality of red tissues and, in fact, their overall visual quality, texture, aroma and macroscopic breakdown under MAP conditions were worse than those of air-stored tissues. [ABSTRACT FROM AUTHOR]