Study of functional, biochemical, and sensory qualities of jackfruit pulp powder produced through optimized foam-mat drying parameters.

Jackfruit (Artocarpus heterophyllus) production is abundant during the summer season in Southeast Asia and is also produced throughout the year in some parts of South India. Attributed to the absence of viable process technology, the pulp is predominantly consumed fresh and has not been used effectively for other applications such as in ice cream, beverages, custard preparations, or as a flavor enhancer. The conversion of the high sugar-containing pulp to powder is difficult. Hence, the foam-mat drying of jackfruit pulp was carried out using different foaming agents and stabilizers. The effect of maltodextrin (MD; 3%, 4%, and 5% w/w), glycerol-monostearate (GMS; 2%, 3%, and 4% w/w), or soy protein (SP; 0.5%, 1%, and 1.5% w/w), and 0.5% methylcellulose added to the pulp at a concentration of 8 °Brix on foam expansion (FE; %), foam retention (FR; %), total carotenoids (TC; mg/100 g pulp), and overall acceptability (OA) were investigated, and their levels were optimized using central composite design of response surface methodology. The foam mats were dried at a drying air temperature of 70°C along with a foam thickness of 4 mm. The samples were evaluated based on drying time, foaming, functional, biochemical, and sensory qualities. The optimum levels of MD and GMS were 3.96% (4.0%) and 3.01% (3.0%), respectively, which led to the foam-mat-dried jackfruit powder with properties within the desirable range. At these optimum conditions, the predicted FE, FR, TC, and OA were 69.84%, 89.42%, 0.152 mg/100 g pulp, and 7.73, respectively. The optimum levels of MD and SP were 3.95% (4.0%) and 1.02% (1.0%), respectively, and the corresponding properties (considered as responses) of this foam-mat-dried jackfruit powder such as FE, FR, TC, and OA were 74.45%, 84.80%, 0.14 mg/100 g pulp, and 7.6, respectively. PRACTICAL APPLICATION: This study is one of the few studies that is focused on the development of a technique for the long-term preservation of jackfruit powder for further applications that will also reduce the wastage of jackfruit attributed to its fast perishability. This technology can be replicated in other parts of the world. This article has demonstrated foam-mat drying as a useful technique to achieve high-quality jackfruit pulp powders with desirable drying, foaming, functional, biochemical, and sensory qualities using different foaming agents and stabilizers.

Development and performance evaluation of hand-operated mango seed decorticator.

Mango seed kernel, a by-product of mango fruit can be consumed as the safe food if properly processed. A hand operated mango seed decorticator was developed to substitute the unhygienic and unsafe existing method. The device consisted of four major sections such as frame support, feeding unit, sliding unit and decorticating unit. Provisions were made to position the seeds inside the seed holder and the splitting blades to penetrate and break open the stony endocarp along the cleavage. The performance of the machine was evaluated and was compared to that of traditional method. The device resulted in higher whole kernel recovery (85.95 ± 1.53%), decortication capacity (1.92 ± 0.04 kg h-1) than traditional method with 58.37 ± 1.76% and 1.10 ± 0.09 kg h-1, respectively. Traditional method incurred higher material loss with broken kernels making them unsafe for consumption if not processed quickly. Statistical analysis also indicated that the efficacy of traditional method was dependent on personal skill as there was operational variability in the data set with higher coefficient of variation. Therefore, the developed mango seed decorticator is expected to assist in utilization of mango kernel as safe food as well as to reduce the drudgery of the operation. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-021-05256-5.

Standardization of process protocol for isolation of starch from mango kernel and its characterization.

BACKGROUND: The major by-products of mango processing are the seeds, which represent approximately 15-20% of the fruit. The process protocol for isolation of starch from mango kernel was standardized based on starch yield, starch purity and colour values using centrifugation and chemical method. Optimized starches obtained from both methods were further investigated for estimation of functional properties and were characterized through Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, differential scanning calorimetry and pasting properties analysis. RESULTS: The slurry making of mango kernels with a solid-to-water ratio of 1:3 at a centrifugation frequency of 3 times was found to be the best among all the experimental combinations (solid-to-water proportion (1:2, 1:3 and 1:4, w/v) and centrifugation frequency (2, 3 and 4 times)) with a starch yield of 48.43 ± 1.08% and purity of 76.46 ± 0.83%. In the chemical method of starch isolation (washing was done with 0.1 mol L-1 NaOH and 0.1 mol L-1 HCl at three levels each), the sample treated with 60% (w/v) 0.1 mol L-1 NaOH and 10% (w/v) 0.1 mol L-1 HCl resulted in 36.50 ± 0.58% starch yield with a purity of 92.03 ± 0.87%. Among the functional properties, the chemically isolated starch showed significantly higher paste clarity (45.79 ± 2.36%) than starch obtained using the centrifugation process (12.50 ± 1.57%). The chemically isolated starch also exhibited better colour attributes, which were very close to those of laboratory-grade starch. CONCLUSION: Detailed characterization studies inferred that both the starches possessed good functional, structural and thermal properties, indicating suitability for food and non-food applications. © 2021 Society of Chemical Industry.

Isolation, characterization, modification and uses of taro starch: A review.

Taro is a major root crop utilized widely for diverse food and non-food applications. Taro corms are processed into various forms before consumption, which makes them digestible and palatable, extends the shelf life and reduces post-harvest losses. Taro corm contains starch as the major carbohydrate, accounting up to 70-80% of the whole dry matter. The starches obtained from different cultivars and sources significantly differ in physical, chemical, thermal, morphological, and functional properties, which can be explored for varied applications. Starch quality also controls the end-quality of food and industrial products. Several starch modification methods have been studied to improve its positive attributes and to eliminate deficiencies in its native characteristics. These modification methods, which can be categorised into physical, chemical and enzymatic, have proved to improve the characteristics and applications of starch. This review aims to compile the information about the chemical composition, characterization, isolation and modification methods, with an objective of its increased use in food or non-food industries. In addition, challenges and issues in the small-scale processing of taro are discussed. The information available in this review may help in a better understanding and utilization of taro starch.

Design, development and performance evaluation of elephant apple core cutter.

In this study a hand operated elephant apple cutter was developed and the machine parameters (capacity, machine efficiency, and loss percentage, etc.) were studied. The cost and performance of the designed cutter was compared to that of the traditional cutter. The comparative performance evaluation of the designed cutter with that of traditional method indicates that the cutter offered higher sepal yield (82.73 ± 1.5%) and capacity (100-120 kg h-1) than the traditional cutter offered sepal yield (63.01 ± 3.3.4%) and capacity (12-15 kg h-1) with uniform coring of the finished product. The cutter could process around 235-240 number of fruits against around 30-35 by traditional in a time period of 1 h. Core cutter can be used by the farmers or rural entrepreneurs for elephant apple processing and value addition for commercial and therapeutic applications.

Quality comparison of elephant apple juices after high-pressure processing and thermal treatment.

BACKGROUND: In the present work, the effect of high pressure processing (HPP) on the quality parameters (pH, °Brix, total acidity, viscosity, colour, antioxidant activity, total phenols, total flavonoids, microbial flora, and sensory analysis) of elephant apple (Dillenia indica) juice was investigated. The juice samples were analysed periodically (0, 1, 2, 5, 10, 20, 30, 40, 50 and 60 days) during 60 days of storage period and results were compared with thermally processed as well as with untreated (fresh juice) samples. RESULTS: Slight variations had been observed in the quality parameters like pH, °Brix and total acidity. Other parameters like colour values, antioxidant activity, total phenols and total flavonoids were varied significantly (P < 0.05) in between the treated (HPP and thermal) and untreated juice samples. The microbial counts of the HPP treated samples were lower than the other samples. Sensory results also showed similar results to those of the other analyses that the treated samples were better for consumption rather than the untreated samples. The shelf-life of the HPP processed elephant apple juice was established as 60 days at 4 °C. CONCLUSION: This study showed that application of HPP effectively maintained quality attributes and extended shelf life of the elephant apple juice. It may be suggested that application of HPP could be considered for commercial application during storage and marketing. © 2016 Society of Chemical Industry.

Water use optimization in zero energy cool chambers for short term storage of fruits and vegetables in coastal area.

Suitability of zero energy cool chamber (ZECC) for short term storage of fruits and vegetables was studied in coastal districts of Orissa. Quantity of water applied in ZECC was standardized. The optimum water level of 75 l/day and 90 l/day was required to achieve a steady and conducive storage environment for storage of fruits and vegetables in summer and winter months, respectively. The chamber was kept average temperature of its environment less by 5-8°C than the outside temperature and maintained more than 90% RH. The ZECC was very effective in extending the storage life of potato, tomato, brinjal, mango, banana and spinach by 3 to 15 days as compared to ambient conditions.

Effect of drying conditions on drying kinetics and quality of aromatic Pandanus amaryllifolius leaves.

Pandanus amaryllifolius is a plant with aromatic leaves, which impart the characteristic flavour of aromatic rice. The quality of aromatic Pandanus leaves dried at low temperature (35 °C) and low RH (27%) in a heat pump dryer was evaluated and compared with those obtained from hot air drying at 45 °C. Thin-layer drying kinetics has been studied for both the conditions. To determine the kinetic parameters, the drying data were fitted to various semi-theoretical models. The goodness of fit was determined using the coefficient of determination, reduced chi square, and root mean square error. Aroma, colour, and overall acceptability determination of fresh and dried leaves were made using sensory evaluation. Drying of leaves took place mainly under the falling-rate period. The Page equation was found to be best among the proposed models to describe the thin-layer drying of Pandanus leaves with higher coefficient of determination. The effective moisture diffusivity values were also determined. The effect of low RH was prominent during the initial drying when the product was moist. The effect of temperature was prominent in the later part of drying, which acted as a driving force for moisture diffusion and hence the total drying time was reduced. Retention of aromatic compound 2-acetyl-1-pyrroline content was more in low temperature dried samples with higher sensory scores.