CONTENTS Vol. 7, No. 2, December 2017

Wild fruits: nutritional and nutraceutical opportunities

Colour is a vital constituent of food and its preferences are influenced by the geographical, sociological and cultural aspects of the populations. The food industry have a vast array of synthetic colours made available in the late 1800s and are used very extensively in various food products. In the last twenty years however, consumers have become increasingly aware of the ingredients in their foods and as such they require foods to be as ‘natural’ as possible. Natural colours, extracted from fruits, vegetables, seed, roots and microorganisms are often called “biocolours” due to their biological origin. These colors are chlorophyll, carotene, lycopene, anthocyanins, flavonoids and anthoxanthins. To identify the active health-promoting ingredients, focus is being made on the properties of the flavonoids, a large class of phenolic compounds that is abundant in fruits and vegetables. Anthocyanins (Greek anthos, flower and Greek kyanose, blue) are the largest group of water-soluble pigments in the plant kingdom known as flavonoids and a larger group of compounds known as polyphenols. Anthocyanins are responsible for the red, purple and blue hues in fruits, vegetables, flowers and grains. Different types of anthocyanin found in naturally are cyanidin, delphinidin, peonidin, malvidine and palargonidin. These are responsible for the attractive colour of Black currant nectar and they have been hypothesized as important antioxidant. Anthocyanin rich mixtures and extracts (not purified compounds) have been used historically to treat? An anthocyanin pigment is composed of an aglycone (an anthocyanidin) esterified to one or more sugars, and have four different structures, which are in equilibrium with one another but the relative amount of these structures,are varied and dependent on the pH and anthocyanin structure, Waste from industrial processes, such as wine or juice production is an excellent source of anthocyanin pigment with potential as a food colourant. An alcohol i.e. methanol or ethanol at different concentrations in combination with an acid i.e. hydrochloric acid or acetic acid or citric acid can be used for the extraction of anthocyanin. But the natural colours have lesser stability than synthetic or artificial colours. Due to highly reactive nature of anthocyanins, they degrade or react with other constituents in the medium, to form colourless or brown coloured compounds. The intensity and stability of the anthocyanin pigments is dependent on different factors. Various methods have been used to evaluate the degradation of anthocyanin i.e. pH differential method and substractive methods. Applications of anthocyanin extracts include coloration of acid fruit preparations, jams and preserves. However, relatively little is known about absorption of anthocyanin compounds after consumption in our body and of the mechanisms by which they exert their beneficial health effects. Increased knowledge of their bioavailability and therapeutic will result in better adoption of anthocyanin-based products as functional foods.

The aim of this study was to investigate the effects of UV- irradiation, hot water dip (HWD) and ethanol vapours on the quality and storage life of chickpea sprouts. Chickpea seeds were washed, soaked and allowed to sprout (24 h). The chickpea seeds after sprouting were subjected to various treatments viz., ethanol vapour (30 min), hot water dip (50 °C for 2 min) and UV-Irradiation (10 kJm-2 for 1 h). The sprouts after treatments were examined at 24 h interval until the spoilage. Sprout length, weight and total plate count were enhanced during storage at both the storage temperature. There was no significant effect of various treatments on sprout length and weight, except in ethanol treatment, where suppression was observed. The total plate count was not significantly affected by various treatments. Sensory quality (for appearance, taste, odour and overall acceptability) decreased with increasing storage period. Hot water dip treatment results in enhancing the shelf-life of sprouts which maintained upto 72 h at room temperature and 120 h at low temperature.

The present research was intended to study the feasibility of incorporation of Aloe vera juice in different ratios for preparation of Aloe vera incorporated peda and assess their storage life at ambient room temperature. The peda samples were analyzed for chemical quality attributes (moisture, protein and acidity) and microbial quality attributes (total plate count and yeast and mould count) during storage at room temperature (37±1°C). The analysis was carried out on 0th, 3rd, 5th and 7th days of storage. A reducing trend was observed in moisture content and increasing trend was observed in acidity content during the storage of peda samples at room temperature over a period of 7 days. The microbial analysis revealed that both total plate count and, yeast and mould count decreased with the increased incorporation of juice. During storage however, both the counts increased.

To assess the microbiological quality of cut cucumbers (Cucumis sativus) sold by itinerant roadside vendors in and around Kolkata, 25 such samples were collected over a two-months period during summer, and tested for total aerobic plate counts (TPCs), coliform and fecal-coliform (Escherichia coli) counts, and other food-borne pathogens. TPCs ranged from 5.093 to 7.477 log cfu/g, 18 samples out of which (72%) had counts >7 log cfu/g. Coliforms were detected in all 25 samples (100%). E. coli was detected in 23 of them (92%), having an average count of 140.80 MPN/g, with 18 samples (78.26%) showing counts >7 log cfu/g. Salmonella and Vibrio cholerae were detected in 12 (48%) and 1 (4%) of the total samples respectively, with 7 of the 12 samples of the former (58.33%), and the latter (100%) showing counts >7 log cfu/g respectively.

Fermented foods are commonly consumed in our daily diets. They not only provide nutritional benefits but can also act as functional foods when optimal level of lactic acid bacteria is achieved which might have probiotic potential. The viability of lactic acid bacteria depends on various intrinsic and extrinsic factors. The packaging material plays an important role in maintaining the shelf life of the product. In the present study various Indian fermented foods were prepared by spontaneous fermentation and effect of packaging material on lactic acid bacteria viability was explored. Products like mix vegetable pickle, raw papaya pickle, mix mango pickle, lemon-ginger and green chilli pickle and kanji was prepared under standardised conditions. Three packaging material; borosil glass bottles, air tight pearlpet bottles and tinted borosil glass bottles were used. As noted from the results that statistically no significant difference was observed. Thus the viability of lactic acid bacteria is not dependent on the material used for packaging unless it is air tight and on the exposure to light till uniform heat is provided.

An α-L-rhamnosidase enzyme [E.C.3.2.1.40] has potential application in food and pharmaceutical industry. Naringin is the dominant flavanoid bitter compound found in citrus fruit juices of the objective of present study was to isolate α-L-rhamnosidase producing fungus, study their morphological and molecular characteristics. A total twelve fungal strains were isolated from agro-industrial waste of lemon and sweet lemon peels for α-L-rhamnosidase enzyme production. Of these, only 4 isolates were capable of producing the α-L-rhamnosidase enzyme to hydrolyze naringin for removal of bitter taste from juices. Fungal isolates were selected according to their higher α-L-rhamnosidase enzyme activities (3.481 IU mL-1). For morphological studies, macroscopic features like colony colour, texture, elevation, growth and margins as well as microscopic characteristics such as the size of conidia and conidiophores, and their arrangements were examined for species differentiation. DNA was isolated from the best α-L-rhamnosidase producing fungal strain, and amplification of 18S rRNA gene, using specific primers ITS-1 and ITS-4 was done. This gene was subsequently sequenced and phylogenetic affiliations was accordingly assigned. Fungal isolate was identified as Aspergillus flavus.

In the present investigation, two strains Lactobacillus brevis UN and Lactobacillus spicheri G2 were used to prepare flavored probiotic curd. Flavor was added in the curd by adding fresh papaya cubes. Four different sets of papaya curd were prepared by taking different combinations of probiotic inoculums during fermentation process. Control was also prepared by using native inoculum of curd. Fermentation of each set was carried out at 30 °C for 4h, product formed was kept at a refrigerated temperature upto 12 days. Sensorial, microbiological and physiochemical analysis of each prepared set of probiotic curd was performed during storage interval. Results obtained after sensorial evaluation revealed that different combinations of L. brevis UN and L. spicheri G2 exerted a significant influence on the sensory quality of the flavored curd. Microbiological evaluation of each set of product proved that there was no loss in total number of viable cells in the product during storage. Statistical analysis of physio-chemical attributes revealed that changes taking place during storage intervals in various sets of Probiotic curd were non-significant.

Rosa damascena also known as desi gulaab, belongs to the Damask variety of rose. It is deep red coloured variety with a sweet fragrance and has been used traditionally in different food preparations. Physico-chemical evaluation revealed that it is a rich source of phytochemicals. The content of phenolic compounds, anthocyanins, ascorbic acid and per cent radical scavenging activity in the fresh petals was 2230 mg GAE/100 g, 98.64 mg/100g, 293.37 mg/100 g and 83.91%, respectively. Fresh petals were also a good source of minerals. The content of potassium, phosphorus, calcium, copper and iron was 153.39 mg/100g, 34.59 mg/100g, 13.78 mg/100g, 1.82 mg/100g and 1.33 mg/100g, respectively. It was concluded from the optimization process that 30:70 of rose petals to sugars, produced syrup with high overall acceptability and in compliance with the specifications of Food Safety and Standardization Authority of India. Whereas, the optimization of temperature revealed that heat treatment at 70°C was most suitable to produce a syrup rich in phytochemicals and high sensorial acceptability.

Proximate composition, anti-nutritional compounds and sensory quality attributes of flakes based on corn and peanut for possible use as ready to eat food. The product takes were prepared as per the standard protocol from corn - peanut blends in the ratios of 100:0, 90:10, 80:20 and 70:30. The analysis of flakes revealed significant differences among different blends. On basis of sensory evaluation the flakes prepared from germinated corn flour: roasted peanut flour of (80: 20) attained highest overall acceptability score (8.57±0.01) and it contained 9. 94 ±0.04 % crude fat, 16.24 ±0.04 % crude protein, 2.56 ±0.01% crude fibre, 3.12±0.02% ash, 64.27±0.07% carbohydrate content and 2.92±0.01 mg/100g β-carotene. The results obtained in this study also showed that flakes prepared from germinated corn flour: roasted peanut flour of 80: 20 contained 14.60±0.01 mg/100g calcium, 0.86±0.01 mg/100g zinc and 0.73±0.01 mg/100g iron.

Value added fermented food products (naan, kulcha, bread, bhatura, vada and wadiyan) were developed by using dehydrated curry leaves at different levels i.e. 2.5 and 5 per cent. Highly acceptable samples supplemented at 2.5 and 5 per cent level were analysed. All the developed products using dehydrated curry leaves were found to have significantly higher content of protein ranging from 5.54-15.40%, fibre 0.36-1.73% and total ash 1.61-3.63% as compared to unsupplemented (control) samples. However, there was also a significant increase in antinutritional components of test samples of fermented food products as compared to the control samples. The oxalate content of test samples ranged from 22.40 to 100.81 mg/100g. The phytate phosphorus content was found to be the highest in wadiyan (136.13 mg/100g) and lowest in kulcha (26.60 mg/100g). Trypsin inhibitor (TI) content of test samples ranged from 51.24 to 183.03 TIU/g of protein and were found to be highest the in wadiyan and lowest in bread. Efforts to reduce the content of anti nutritional factors in these foods are required to be made.

Conjugated Linoleic Acid (CLA) isomers have attracted significant attention due to their important functional traits with plenty of health prospects to humans. Many Lactic Acid Bacteria (LAB) demonstrate the ability to produce CLA isomers C18:2 cis-9, trans-11 and C18:2 trans-10, cis-12 from the Linoleic Acid (LA) in-vitro. In the present study, 16 LAB with ability to produce CLA were isolated from diverse ecosystem. Three LAB isolates, CMLAB2, BMLAB1 and PMLAB1 had shown their potential to convert in-vitro free LA to CLA. The FAME extracts of CLA produced in fermentation experiments by these isolates were studied. The isolates CMLAB2, BMLAB1 and P2MLAB1 were found to produce 21.21; 14.68; 6.35 μg/ml of CLA respectively. Among these isolates, CMLAB2 isolate was found to produce physiologically important and most studied c9, t11CLA and t10, c12 CLA isomers in significant amount in-vitro. Upon characterization of this isolate, it was identified as a species of Lactobacilli.

Minimal processing adds to convenience of consumption and marketing of fruits and vegetables suitable for retail markets. In the present study, an attempt has been made to freshly process and pack Moringa oleifera leaves in different packaging materials and storage conditions as a convenience product. Freshly harvested Moringa leaves were stripped in a mechanical stripper to remove the leaflets from the branches, washed in chlorinated water, surface dried and packed in different packaging materials viz., LDPE (40 micron), LDPE (80 micron), Polypropylene (40 micron), Polypropylene (60 micron), at different levels of ventilation (0, 1% & 2%) and kept for storage under ambient (29±33 °C, 50-70% RH) and refrigerated (5±2 °C, 90-95% RH) conditions. The physiological changes based on Weight Loss, % wilting and the changes in the nutrient content (chlorophyll, vitamin C, vitamin A & Iron) were periodically analysed during storage. The study revealed that packaging treatment with Polypropylene 40 micron at 1% vent was found to be the best for freshly processed Moringa leaves under ambient conditions and LDPE 80 micron with 1% vent was found to be best for refrigerated storage. Quality analysis revealed that there was not much difference in the nutrient content of Moringa leaves except for ascorbic acid content during storage.

In the present investigation physical, chemical and functional properties of apple, carrot and beetroot pomace powder were evaluated and compared in order to access its potential for valorisation of food products. Physical properties of pomace powders indicated that apple pomace powder (APP) had good flowability characteristics whereas carrot pomace powder (CPP) and beetroot pomace powder (BPP) were having fair flowability. All the three pomace powders were having intermediate cohesiveness. CPP had the highest water holding capacity (WHC), swelling capacity (SC) and oil absorption capacity (OAC) whereas WRC (water retention capacity) was found to be highest in the BPP. CPP and BPP showed good ash content while the highest crude fibre content was found in APP. Overall, all three pomace powders were having high crude fibre content and good hydration properties. The results obtained suggested that all three pomace powders are good source of dietary fibre and thus can be used for fibre enrichment in food products.

Laboratory experiments were carried out to evaluate the effect of different tomato fruit decontamination processes like washing, cooking, washing plus cooking and dipping in chemical solutions on reduction of profenofos and cypermethrin residues after application of ready-mix formulation Roket 44EC (profenofos 40% +cypermethrin 4%) on the crop. Ready-mix formulation Roket 44EC was applied twice at the rate of 1ml/L at 15 days interval. Tomato fruits were collected at 0 (2 hours) and 3 days interval after the last spray and subjected to decontamination processes. Washing of zero day contaminated fruit samples provided 32.95-72.08% relief from profenofos residues and 38.12-75.17% relief from cypermethrin residues. Cooking degraded profenofos residues up to 44.74-65.77% and cypermethrin residues by 61.00-66.02%. Washing plus cooking was found to be the best technique in removing the residues. Washing of fruits in solutions like NaOH (2%) and HCl (0.05%) has also shown a good relief from profenofos and cypermethrin residues.

Liquid Chromatographic analysis was done to determine the antimicrobial drug residue in baby foods and bovine milk. Different baby foods and bovine milk samples were subjected to analysis of the antimicrobial drug residues. Bovine milk, Dexolac-1, Dexolac-2, first food, Nestogen, Lactogen-2, Cerelac-1, Cerelac-2 and Nutricia Infacare were analysed for chloramphenicol and sulfamethazine residues. While milk collected from different parts of country were analysed for albendazole, fenbendazole and diminazene residue. The results in this study indicated that Bovine milk and baby foods which were analysed for antimicrobial drug residue had their quantities and were safe to use.

The present study was undertaken to formulate and analyze the nutritional composition of value added food products prepared by the incorporation of finger millet flour (Eleusine coracana), pearl millet flour (Pennisetum glaucum) and drumstick leaves (Moringa oleifera). Three value added food products were namely ‘Idli’, ‘Dhokla’ and ‘Uthapam’ were analyzed for proximate constituents and total phenolic content. ‘Idli’, ‘Dhokla’ and ‘Uthapam’ were prepared by the incorporation of finger millet flour, pearl millet flour and drumstick leaves in ratio of 20:20:10. Results showed that ‘Idli’, ‘Dhokla’ and ‘Uthapam’ were rich in calcium, vitamin C and total phenolic content (141.48mg/100g, 23.42mg/100g and 712.43mg/100g), (154.84mg/100g, 24.78mg/100g and 622.6mg/100g) and (142.91mg/100g, 25.23mg/100g and 687.03mg/100g) respectively. Incorporation of finger millet flour, peal millet flour and drum stick leaves improved the nutritional composition of the products. It can be concluded that these products prepared from millets and drumstick leaves have potential to in the prevention of ageing and various diseases associated with oxidative stress.

Amla fruit is known for its antioxidant activity (Vitamin C) and medicinal properties. Value added products make the fruit available throughout the year and help to promote the use of amla among the public. Hence, an attempt was made to standardized sweet based products viz., jam, squash and jelly with different treatments. The prepared amla products were standardized on the basis of sensory evaluation. The bio-active components and sensory evaluation of amla products were analysed during storage. The shelf-life studies of amla jam, squash and jelly were also determined at room temperature.