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Pickling or salt curing is one of the major traditional processes to increase the shelf life of bitter gourd in India. No information is available about optimization of salt curing of bitter gourd and the related changes in its quality. Moreover, specific investigations are needed to evaluate individual susceptibility of fruit and vegetables to osmotic dewatering with pre-treatment to obtain new minimally processed food products. The purpose of this study is to optimize the salt curing process with blanching as pretreatment for bitter gourd.

A study was conducted to optimize the blanching and other process factors of salt curing (solution concentration and treatment time) based on mass transfer and quality factors of bitter gourd using response surface methodology. Experimental design was made using central composite rotatable design with different time of blanching, solution concentration and treatment time. The colour, firmness, water activity and other mass transfer kinetic parameters were used for optimization.

Blanching had significant effect (p < 0.001) on water loss (WL), weight reduction (WR), solid gain (SG), water activity and firmness of bitter gourd. Mass transfer kinetic parameters like WL, SG and normalized solid content increased and normalized moisture content was found to decrease with increase in solution concentration and curing time. Relationships between process variables and quality factors were established in either quadratic or linear form with higher R² values. A 15 per cent solution concentration for the period of 5 h with the blanched samples at 800°C for 5.26 min was found to be the optimum condition for osmotic dehydration to achieve maximum WL and SG, minimum water activity and minimum changes in firmness.

The optimized combinations for the salt curing process would be more helpful for the processors and other stakeholders involved in the pickling process by reducing energy and other input resources.

Mostly in India, the pickling process is carried out at micro- and small-scale level and in an unorganized way. This study would help those involved to reduce their input resources and to organize the process, thus leading to more dividends to the stakeholders and optimum price to the end-users. For the medium- and large-scale processing units, this study would give insight to automate the whole process in an efficient manner.

This study was performed using sophisticated and higher-end instruments. The data were observed meticulously and analysed with proper statistical tools, increasing the credibility of the study. This study gives concrete results which are directly useful to the stakeholders.

The purpose of this paper is to evaluate the total polyphenolics, flavonoids and antioxidant properties of a ready to‐eat snack food prepared from Agaricus bisporous. A comparison of these properties with the raw, unprocessed mushroom was also carried out.

Extracts of raw and snack mushrooms (osmotically dehydrated, dried and spiced and following sensorial analysis) were analyzed for antioxidant activities using DPPH and ABTS radical scavenging methods. Flavonoids were determined by the method of Jia et al. Total polyphenolics (free and bound) were determined by the Folin‐Ciocalteu method; reducing power and hemolysis inhibition of the extracts were determined by the methods of Oyaizu and Zhang et al.

Scavenging activity of free extracts of raw and dry snack mushrooms on DPPH radical were 76 per cent and 72 per cent respectively. The ABTS radical scavenging activity of the free extracts of raw sample was 2.76 mg ascorbic acid equivalents/100 g and 2.67 mg ascorbic acid equivalents/100 g snack mushroom. Both free and bound polyphenolic contents in mushroom snacks were slightly higher than raw mushrooms, total flavonoids levels decreased marginally in snack mushrooms. Hemolysis inhibition was decreased (marginally) in free extract of snack mushroom as compared to raw mushroom whereas total reducing power of snack mushroom extract increased significantly. The antioxidant status was unaffected following storage of the snack at ambient temperature for up‐to 15 days.

Mushrooms snacks may serve as a good alternative for currently existing snack foods since they retain a significant amount of polyphenolics and antioxidants; mixed with other commonly used snack foods it may provide beneficial health effects to the consumers economically.

A simple, economical process for preparation of Agaricus bisporous snack using sequential application of osmotic dehydration and drying was optimized; the snack mushrooms possessed functional properties comparable to raw, unprocessed mushrooms.

This paper reports for the first time a simple, economical process for preparation of functional snack food from mushrooms.

Leafy vegetables are known to be highly perishable because of high moisture content, which had resulted in applications of different preservative methods. However, these methods were not without certain limitations during storage. Osmotic pre-dehydration had been proved to be a better alternative because of high retention and improvement in nutritional qualities and stability during storage. This study aims to investigate the osmotic pre-dehydration of fluted pumpkin (Telfairia occidentalis) leaves.

Fluted pumpkin (T. occidentalis) leaves were pre-dried using sucrose, corn syrup and sodium chloride solutions as osmotic agents, while unosmo-predried leaves were used as the control. Both osmo-predehydrated and unosmo-predried leaves were dried in a hot air oven, whereas the effect of the osmotic agents on the nutritional qualities was investigated using standard protocols.

There were significant differences (p-values ranged from 0.001 to 0.030) in the proximate compositions of samples. Osmo-predried leaves recorded higher mineral contents in Ca, Cu, Fe, K, Mg, Mn and Na. Osmotic pre-dehydration by NaCl had a significant effect (p = 0.02) on ascorbic acid. The amino acid profile of the oven-dried leaves (unosmo-predried) showed that histidine and cysteine recorded high amino acid scores of 120.42% and 135%, respectively. Threonine (43.73%) recorded the highest essential amino acid score (without histidine). The economic evaluation indicated the percentage cost index difference of leaves treated with NaCl as 2.08%, sucrose (11.19%) and corn syrup (16.43%).

The high proportion of beneficial elements such as calcium, magnesium, phosphorus, potassium and appreciable chemical compositions of the osmo-predried leaves compared to unpre-dried leaves proved osmotic pre-dehydration as a value-added technique for preservation of leafy vegetables. The best osmotic agent was sodium chloride. This process could be applied on a small scale for the development of self-entrepreneurs and home-scale industries.

The aim of the study was to evaluate the effect of osmo-convective dehydration using two drying temperatures (50 and 60°C) on the physico-chemical properties, shelf life and sensory acceptability of jackfruit berries.

Four treatments were used as follows: T1 – Jackfruit berries dried in an oven at 50°C; T2 – Jackfruit berries dried in an oven at 60°C; T3 – Jackfruit berries pre-treated with an osmotic-sucrose solution (60 Brix concentration) and oven-dried at 50°C and T4 – Jackfruit berries pretreated with osmotic solution (60 Brix concentration) and oven-dried at 60°C. Berries' shelf life was monitored by moisture analysis, water activity (Wa) and microbiological analysis. The influence of treatments on physico-chemical properties and sensory quality was also investigated.

Osmo-convective dehydration at 50 and 60 C significantly (p = 0.001) reduced moisture content and Wa. All treatments increased the shelf life of jackfruit berries within 30 days of storage. Regarding sensory analysis, the T3 treatment was significantly (p = 0.001) the most preferred by the tasters.

In general, the results indicated that osmo-convective dehydration at 50 C has great potential to be a maid in the processing of minimally processed jackfruit berries, as, in addition to providing the product with high stability, it was the one with the greatest acceptability by the tasters.

Inclusion of bioactive compounds in food products is promising for developing novel functional food products. The feasibility of incorporating flavonoids and low-calorie sugar substitutes in fresh-cut apple through osmotic dehydration (OD) was investigated.

The impregnation of quercetin and fisetin in apple cubes was tested. The effects of different osmotic agents, sucrose and sorbitol:mannose, on the water loss (WL) and sugar gain of the samples were studied at 25 and 40 °C for eight hours.

Temperature was a significant factor in the mass transfer kinetics, that is to say, higher temperatures resulting in higher rates. The molecular weight of the solutes in the osmotic solution also affected the OD kinetics and flavonoids uptake, as well as the physico-chemical quality.

Overall, the results indicate that OD using alternative low-calorie and health-promoting solutes can be an effective treatment to simultaneously enrich fresh-cut apples with senolytic flavonoids, therefore presenting a great potential for a novel functional food product.

Fresh catfish (Clarias gariepinus) is highly perishable. This paper aims to investigate the drying characteristics and quality of body-mass dehydrated catfish to determine the effective dehydration parameters for preservation.

Brine concentration (3-9 per cent), brining time (30-90 min) and drying temperature (90-130°C) interacted using the response surface methodology. Preliminary experiments were conducted to select treatments. Moisture content and ratio and drying rate were determined and fitted into five thin-layer drying models; the goodness of fit was evaluated by average grade ranking of the regression parameters. Proximate compositions and microbial load of dehydrated catfish were determined using standard methods.

Treatments with 110°C gave initial higher drying rate (0.034-0.043 kg H₂O/kg solid/h) and shorter drying time (20-21 h). Drying occurred at two falling rate periods. Midilli model ranked first in fitting the drying data. It explained up to 99.6-99.7 per cent of the total variations in the independent variables with low values of error terms; RMSE was 0.02131-0.01794 and χ² was 0.00037-0.00043, indicating good predictive quality. Processing parameters positively and significantly (p < 0.05) influenced the proximate compositions of dehydrated catfish. Treatment: 6 per cent brine, 90 min and 110°C presented the most effective dehydration parameters for quality preservation of body-mass catfish.

The dehydration technique used in this study could enhance nutritive quality and storage stability of body-mass dehydrated catfish that could serve as a useful and convenient tool for commercial application.

Hygienically processed dehydrated catfish of good quality could be used as a source of nutrients to ameliorate malnutrition and reduce post-harvest losses of catfish.

The effective processing parameters established is an important step to harness the high nutrients and economic values embedded in catfish.

This study aims to evaluate the use of vacuum impregnation (VI) for developing vitamin E fortified fresh‐cut apples (Fuji).

A 20 per cent high fructose corn syrup (HFCS) or edible coating materials of 1 per cent hydroxypropyl methylcellulose (HPMC) and 1 per cent calcium caseinate (CC) were used to make VI solutions, and 0.4 per cent α‐tocopherol acetate, 7.5 per cent gluconal cal^{\tf="Pi3" \char"31} (GC) and 0.04 per cent zinc lactate (ZL) were incorporated into the VI solutions. Vitamin E content, color, and selected physicochemical properties of fortified fresh‐cut apples were analyzed.

Results showed that VI treatment with 20 per cent HFCS solution containing 0.4 per cent α‐tocopherol acetate increased vitamin E content up to 21.8 mg in 100 g of fresh‐cut apples, while 12.0 mg and 20.2 mg vitamin E were achieved when using 1 per cent HPMC or 1 per cent CC as VI solutions, respectively. Calcium and zinc content were also increased to 146.6 mg and 1.7 mg in 100 g of apples, respectively, when adding 7.5 per cent GC and 0.04 per cent ZL along with the vitamin E into the VI solutions. Use of HFCS, HPMC and CC as VI solutions resulted in different effects on the physiochemical properties of fresh‐cut apples. While HFCS is promising for vitamin E fortification and retention of natural apple color, HPMC and CC can be used to achieve similar vitamin E fortification with the least impact on the soluble solids and moisture contents of apples.

The study demonstrates that there is great potential for developing high quality, vitamin E and minerals fortified fresh‐cut apples using vacuum impregnation technology, thus further enhancing the health benefit of the apples.

The aim of this work was to study the effect of the different levels of salt and the temperature on some physico-chemical and colour change properties of microwave-dried beef round (M. semitendinosus).

The samples were pretreated with different temperatures (0°C, 40°C and 50°C) and salting (0, 1.5, 2.5%). Later these samples have been dried by the microwave energy at 540 W for seven minutes. Some physical properties (water activity, moisture content, change in diameter, change in thickness, change in shrinkage ratio) and texture, colour and microscopic surface structure analysis were conducted in dried beef round samples.

As a result, the colour and moisture were the most affected factors. Also, physical and microstructural characteristics were affected by salting and pre-drying. In addition, while the textural structure did not show a significant difference, meat weight and water activity varied.

Meat obtained from a local butcher in Konya was used as the study material. In addition, only a special part of the meat (M. semitendinosus) was used in the study. In the drying process, the parameters were determined as 540 W and 7 min. These are the limitations of the research.

All changes that can occur in the physical properties of the meat after the drying process were examined. The structure of beef round samples formed by microwave drying was shown by using electron microscope. The effects of pretreatment such as salting and pre-drying have been examined on microwave drying.

The purpose of this paper is to explore consumers’ health perception and demonstrate its relevance in product and process design in early stages of new product development.

A dried mango was used as a case study involving three countries: Indonesia, China and the Netherlands. Data were collected from nine focus groups (n=53 participants) and were content-analysed to acquire in-depth insights.

Four themes of health perception emerged, namely, nutrition, naturalness, taste and well-being, which were all expressed on different levels of abstractness. Participants’ health perception of dried mango varied, it is related to the product category it is compared with, e.g. candy or fresh fruit, and the eating context, e.g. position in the diet either as a snack or a meal. In extension participants mentioned product and process characteristics. Application of the insights into product and process design was performed through iterative interactions between consumer scientists and food technologists. The development of two product concepts was elaborated to transform the insights into technical product and process specifications for a natural dried mango product.

This transformation suggests that iterative interactions are necessary to achieve relevant product and process characteristics in the simultaneous design of the technical product and process specifications based on consumer perceptions.

Fishes are important sources of good and high-quality protein in developing countries. Spoilage and keeping quality of fish especially in the tropics is temperature dependence as high temperature and relative humidity accelerate the process of spoilage and fish keeping quality. Fish dehydration removed moisture and extended the shelf life of dried fish. Drying involves removal of moisture from fish as a result of heat and mass transfer done under controlled conditions. This study delves into various drying techniques and drying kinetics of fish.

The review examines fish drying kinetics and the various drying models applicable to fish drying.

This review showed that moisture content and colour of dried fish are affected by time and power level. It was also found that the moisture content of the dried fish varied according to the drying method used. Also, as drying power and drying rate varied inversely with drying time. Eight different thin layer drying models were examined for evaluation of drying data for all the experimental conditions involving fish drying. It was found that the quality of the dried fish decreased with drying. Higher values of effective moisture diffusivity have been found to increase moisture velocity within fish samples which improve removal of moisture to reach equilibrium moisture content at specified relative humidity. However, based on this, effective moisture diffusivity could be a useful parameter to design an effective drying method in terms of time, energy consumption and cost to prolong the storage life of dried fish samples. Drying kinetics and different drying models were considered and explained. The use of these models was considered to be important in choosing appropriate drying conditions for effective drying and to get good quality dried fish samples.

The review considers few available literatures on the subject matter.

The review explores the possibility of creating more awareness for more in-depth research on fish drying kinetics and their usefulness in fish preservation.

This outcome of this study is important to researchers, policymakers and regulatory agencies in developing countries on fish preservation.