Review of Cocos nucifera L. testa-derived phytonutrients with special reference to phenolics and its potential for encapsulation.

Coconut (Cocos nucifera L.) and its value-added products are rich in medium chain triglycerides, polyphenols and flavonoids with a significant anti-oxidant potential. However, coconut and its products are underutilized for the development of nutraceuticals. Coconut testa is a brown cover of the endosperm, which is characterized with the considerable amount of phytonutrients, especially phenolics and flavonoids. The nutrient rich coconut testa is generally diverted for the production of animal feed or abandoned. Around 10-15% of the coconut kernel is removed as testa while preparing coconut desiccated powder. The coconut testa from the virgin coconut oil (VCO) industry also remains underutilized. Nevertheless, biochemical characterization of coconut testa has revealed its enormous anti-oxidant and nutraceutical potential. On the other hand there are reports describing the suitable encapsulation techniques to develop nutraceuticals from the plant-derived bioactives. In this context this review explores the prospect of utilizing the coconut testa-derived phytonutrients in developing a nutraceutical product.

Contemporary Developments and Emerging Trends in the Application of Spectroscopy Techniques: A Particular Reference to Coconut (Cocos nucifera L.).

The number of food frauds in coconut-based products is increasing due to higher consumer demands for these products. Rising health consciousness, public awareness and increased concerns about food safety and quality have made authorities and various other certifying agencies focus more on the authentication of coconut products. As the conventional techniques for determining the quality attributes of coconut are destructive and time-consuming, non-destructive testing methods which are accurate, rapid, and easy to perform with no detrimental sampling methods are currently gaining importance. Spectroscopic methods such as nuclear magnetic resonance (NMR), infrared (IR)spectroscopy, mid-infrared (MIR)spectroscopy, near-infrared (NIR) spectroscopy, ultraviolet-visible (UV-VIS) spectroscopy, fluorescence spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and Raman spectroscopy (RS) are gaining in importance for determining the oxidative stability of coconut oil, the adulteration of oils, and the detection of harmful additives, pathogens, and toxins in coconut products and are also employed in deducing the interactions in food constituents, and microbial contaminations. The objective of this review is to provide a comprehensive analysis on the various spectroscopic techniques along with different chemometric approaches for the successful authentication and quality determination of coconut products. The manuscript was prepared by analyzing and compiling the articles that were collected from various databases such as PubMed, Google Scholar, Scopus and ScienceDirect. The spectroscopic techniques in combination with chemometrics were shown to be successful in the authentication of coconut products. RS and NMR spectroscopy techniques proved their utility and accuracy in assessing the changes in coconut oil's chemical and viscosity profile. FTIR spectroscopy was successfully utilized to analyze the oxidation levels and determine the authenticity of coconut oils. An FT-NIR-based analysis of various coconut samples confirmed the acceptable levels of accuracy in prediction. These non-destructive methods of spectroscopy offer a broad spectrum of applications in food processing industries to detect adulterants. Moreover, the combined chemometrics and spectroscopy detection method is a versatile and accurate measurement for adulterant identification.

Low-density polyethylene based nanocomposite packaging films for the preservation of sugarcane juice.

Low density polyethylene (LDPE) based nanocomposite films made from different levels of nanoclay, compatibilizer and thickness were evaluated for the storage stability of sugarcane juice for 60 days under ambient condition. During the storage period, important physico-chemical properties such as pH, total sugars, total soluble solids and overall acceptability were decreased with respect to increased level of nanoclay and compatibilizer as well as decreased thickness of film. Total plate count was nil till the storage period of 15 days and then there was an increase in microbial population. Similarly, the overall color difference was also increased during the storage period. The better storage stability with respect to biochemical characteristics, overall acceptability and microbial load was recorded in the 100 µm thick LDPE nano composite films developed from 93 percent LDPE, 2 percent nanoclay and 5 percent compatibilizer.

Effect of coconut milk, tender coconut and coconut sugar on the physico-chemical and sensory attributes in ice cream.

The investigation was aimed to understand the effect of coconut milk, tender coconut pulp, tender coconut water and coconut sugar on the qualitative attributes of ice cream. Five ice cream formulations were laid out to substitute the major ingredients of ice cream such as, dairy milk and butter with coconut milk, skim milk powder with tender coconut pulp, refined sugar with coconut sugar and potable water with tender coconut water. Two of the formulations were exclusively non-dairy, third one was the standard dairy ice cream, fourth formulation was with the inclusion of coconut sugar in the standard ice cream and the fifth one was standard ice cream with tender coconut and coconut sugar. Proximate composition of the raw materials revealed that coconut milk, tender coconut pulp and coconut sugar can contribute to the solids-non-fat content in ice cream. Significant effect (p< 0.01) was observed on physico-chemical qualities of the mix and ice cream. Total solids, density and total soluble solids of the ice cream mixes were positively correlated. Density, one of the key physical parameters was ranged from 0.98 to 1.13 g/ cm3. Though coconut milk is acidic, the percent titratable values were within the limit. Non- dairy ice cream formulations obtained lower overrun (p < 0.001). There was a negative correlation between percent fat of ice cream and overrun. Crude fat and protein contents of the ice creams were ranged from 10.52-11.62 % and 3.42-4.94 % respectively. Inclusion of coconut products resulted in increased total phenolics and minerals (ash). Non-dairy formulations were preferred over dairy counterpart with respect to flavour and taste during the sensory evaluation carried out with four different age groups. Thus, the study enlightens the potential scope of utilization coconut products in ice cream industry. It also gave a lead towards developing non-dairy/ vegan delicacy on coconut. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-021-05279-y.

Reaction kinetics of physico-chemical attributes in coconut inflorescence sap during fermentation.

The study on fermentation kinetics of the coconut inflorescence sap is important to understand its shelf life at different storage conditions and to develop suitable value added products. The coconut inflorescence sap collected by using in-house developed coco-sap chiller device is called Kalparasa. The fermentation characteristics of Kalparasa were investigated at every 1-h interval under ambient (31 ± 2 °C) and refrigerated (5 ± 1 °C) storage conditions. The results reveal that pH of the sap and total sugar content decline rapidly under ambient conditions than under refrigerated conditions. Acidity, turbidity, and reducing sugar content significantly (p < 0.001) increases for the sap stored under ambient conditions. The reaction rate constant (k) of the vitamin C and total sugar degradation increases with the atmospheric fermentation. The degradation kinetics of vitamin C and total sugar in Kalparasa during natural fermentation (ambient condition) follow second-order equation whereas the reducing sugar follows the first-order equation.

Selection of process parameters for producing high quality defatted sesame flour at pilot scale.

The present work was undertaken to study the effect of pearling duration, soaking time, steaming duration and drying temperature on the quality of sesame seeds and mechanically extracted partially defatted sesame cake. On the basis of quality attributes i.e. high protein, low crude fibre, low residual oil and low oxalic acid, the optimum process parameters were selected. The combination of 20 min of pearling duration, 15 min of soaking, 15 min of steaming at 100 kPa pressure and drying at 50 °C yielded high quality partially defatted protein rich sesame flour as compared to untreated defatted sesame flour. The developed high quality partially defatted protein rich sesame flour may be used in various food applications as a vital ingredient to increase the nutritional significance of the prepared foodstuffs.

Drying characteristics of paddy in an integrated dryer.

Drying characteristics of paddy (long grain variety PR-118 procured from PAU, Ludhiana) in an integrated dryer using single as well as combined heating source was studied at different air temperatures. The integrated dryer comprises three different air heating sources such as solar, biomass and electrical. Drying of paddy occurred in falling rate period. It was observed that duration of drying of paddy from 22 to 13 % moisture content (w.b.) was 5-9 h depending upon the source of energy used. In order to select a suitable drying curve, six thin layer-drying models (Newton, Page, Modified Page, Henderson and Pabis, Logarithmic and Wang and Singh) were fitted to the experimental moisture ratio data. Among the mathematical models investigated, Wang and Singh model best described the drying behaviour of paddy using solar, biomass and combined heating sources with highest coefficient of determination (r (2)) values and least chi-square, χ (2), mean bias error (MBE) and root mean square error (RMSE) values. However, Page model adequately described the drying behavior of paddy using electrical heating source.

Storage stability of banana chips in polypropylene based nanocomposite packaging films.

In this study, polypropylene (PP) based nanocomposite films of 15 different compositions of nanoclay, compatibilizer and thickness were developed and used for packaging and storage of banana chips. The effect of nanocomposite films on the quality characteristics viz. moisture content (MC), water activity (WA), total color difference(TCD), breaking force (BF), free fatty acid (FFA), peroxide value(PV), total plate count (TPC) and overall acceptability score of banana chips under ambient condition at every 15 days interval were studied for 120 days. All quality parameters of stored banana chips increased whereas overall acceptability scores decreased during storage. The elevation in FFA, BF and TCD of stored banana chips increased with elapse of storage period as well as with increased proportion of both nanoclay and compatibilizer but decreased by reducing the thickness of film. Among all the packaging materials, the WA of banana chips remained lower than 0.60 i.e. critical limit for microbial growth up to 90 days of storage. The PV of banana chips packaged also remained within the safe limit of 25 meq oxygen kg(-1) throughout the storage period. Among all the nanocomposite films, packaging material having 5 % compatibilizer, 2 % nanoclay & 100 µm thickness (treatment E) and 10 % compatibilizer, 4 % nanoclay & 120 µm thickness (treatment N) showed better stability of measured quality characteristics of banana chips than any other treatment.

Design, development and evaluation of a tractor mounted air blast sprayer for coconut and arecanut.

A tractor mounted air blast sprayer was designed and developed to reduce the drudgery involved in the manual spraying of pesticide by climbing coconut tree. The sprayer mounted on a small tractor, prime mover, is operated by the power taken from its power take off (PTO). In this study, the influence of two important parameters viz., blower speed (2250 and 3000 rpm) and tractor speed (1.5 and 2.5 km h-1) at different heights on the spray characteristics such as volume mean diameter (VMD), droplet density, and spray deposition were collected and analysed. The tractor speed of 1.5 kmh-1 and blower speed of 3000 rpm was observed at recommended VMD between 100-200 µm at a height above 21 m. Hence, the tractor speed of 1.5 kmh-1 and blower speed of 3000 rpm was selected for field evaluation. The mean height of the coconut tree in the tested field was 24 m. The mean droplet size and deposition were observed at 124 µm and 7.2 µl cm-2, respectively at 24 m height. The effective field capacity, field efficiency, and fuel consumption were 0.524 ha.h-1, 73.72%, and 4.67 l h-1, respectively.

Physical, Chemical and Functional Attributes of Neera Honey Infused Extrudates.

Owing to the demand for the consumption of healthy extrudates, this study explored the infusion of neera (coconut inflorescence sap) honey in rice flour, corn flour and coconut milk residue blend-based extrudates. Neera honey, the concentrated coconut inflorescence sap, has numerous nutrients and a natural source of essential vitamins. Hence, the potential of neera honey as a biofortifying compound for the production of healthy extrudates was investigated. The rice and corn based extrudates supplemented with different concentration of neera honey have been prepared until the mix reaches 16 and 20% (w.b.) of feed moisture. Effect of addition of neera honey on the physical properties (expansion ratio, bulk density, specific length), functional properties (water absorption, water solubility, oil absorption), biochemical properties (total carbohydrates, total sugar, reducing sugar, phenolics, flavonoids, antioxidants), color parameters(L*, a*, b*), proximate compositions (moisture content, ash, protein, fat) and mineral profile of extrudates were recorded. Results suggest that addition of neera honey had a significant (p ˂ 0.05) impact on all the physico-chemical parameters evaluated. Incorporation of neera honey (feed moisture -20%) resulted in extrudates with less expansion, high bulk density and specific length, having high sugar, protein, phenolics, vitamin C and antioxidant activity. The combination of 60% rice flour + 25% corn flour +15% coconut milk residue samples infused with neera honey upto 16% feed moisture was found suitable for the preparation of nutritious extrudates based on functional characterization and minerals evaluation.

Recent advancements in NIR spectroscopy for assessing the quality and safety of horticultural products: A comprehensive review.

The qualitative and quantitative evaluation of agricultural products has often been carried out using traditional, i.e., destructive, techniques. Due to their inherent disadvantages, non-destructive methods that use near-infrared spectroscopy (NIRS) coupled with chemometrics could be useful for evaluating various agricultural products. Advancements in computational power, machine learning, regression models, artificial neural networks (ANN), and other predictive tools have made their way into NIRS, improving its potential to be a feasible alternative to destructive measurements. Moreover, the incorporation of suitable preprocessing techniques and wavelength selection methods has arguably proven its practical feasibility. This review focuses on the various computation methods used for processing the spectral data collected and discusses the potential applications of NIRS for evaluating the quality and safety of agricultural products. The challenges associated with this technology are also discussed, as well as potential future perspectives. We conclude that NIRS is a potentially useful tool for the rapid assessment of the quality and safety of agricultural products.

Dynamics of biochemical attributes and enzymatic activities of pasteurized and bio-preserved tender coconut water during storage.

The potential of bio-preservatives, namely, nisin, natamycin, and polylysine, as viable alternatives to chemical preservatives for storage of tender coconut water (TCW) during refrigerated storage (5 ± 2°C) was explored. Bio-preservative treatments were carried out after optimized heat treatment (85°C for 5 min) of TCW to establish its storage characteristics. Various concentrations (up to 125 ppm) of bio-preservatives were used for the preservation, and quality parameters of resultant TCW were assessed based on physicochemical characteristics and Food and Agriculture Organization (FAO) guidelines and statistical analysis applied. Analysis of variance (ANOVA) and post-hoc test revealed that pH and overall acceptability (OA) are the major governing factors that determine spoilage of TCW (p < 0.05). Overall, the polylysine combination was found to be most effective in ensuring quality retention of TCW. It was concluded that pasteurized TCW shelf life could be extended up to 20 days using bio-preservatives.