International Symposium on Agriculture and Environment - 2020

Quality analysis of commercially available selected bottled drinking water samples in Jaffna district

Fri, 07 May 2021 00:00:00 GMT

Quality analysis of commercially available selected bottled drinking water samples in Jaffna district Nitharshana, R.; Sarathadevi, R.; Vasantharuba, S. Bottle water is a great beverage choice for hydration and refreshment because it's consistent quality, safety, and convenience. Quality of safe drinking water refers to physicochemical and microbiological parameters that meet the WHO (World Health Organization) guidelines of national standards. Therefore, this study was aimed to evaluate the quality of selected bottled drinking water samples available in Jaffna District, Sri Lanka. Randomly selected ten different brands of bottled drinking water samples were collected from bottled drinking water selling shops. For the quality analysis, water samples from two batches were tested for physiochemical (pH, Electrical conductivity, Total Dissolved Solids, Total Suspended solids, Turbidity, Color, Odor, Taste, iron, Nitrate, Nitrite, Sodium, Potassium, Total Hardness, Magnesium, Calcium, Alkalinity, and Chloride) and Microbiological (Total bacterial Count) parameters. The results of the above samples were compared with the SLS (Sri Lankan Standards) recommended level to ensure the quality of the drinking water samples. All samples’ pH values varied between the ranges of 6.9 - 9.61, whereas electrical conductivity values varied between 12.58 - 202.58 µS/cm and total alkalinity and turbidity values varied between the ranges of 93.33 - 203.33 mg/L and 0.215 - 0.321 NTU, respectively. Further, total dissolved solids, sodium, total suspended solids, potassium, iron, hardness, magnesium, chloride, and calcium content of all studied water samples were 2.491 – 99.678 mg/L, 0.5 – 17.25 ppm, 0 mg/L, 0.270 – 1.50 mg/L, and 0 - 0.681 mg/L, 5.01 – 10.73 mg/L, 1.1-2.06 mg/L, 37.86 – 62.71 mg/L, and 1.96 – 17.79 mg/L, respectively. Moreover, nitrite and nitrate values for water samples varied between 0 to 0.0038 mg/L and 0.683 to 2.983 mg/L, respectively. All studied water samples were colourless, tasteless, and odourless for organoleptic analysis. Total microbial count varied between 0 and 13 CFU. According to the results, it is obvious that bottled drinking water has good quality for the selected samples. Among all samples studied for the physicochemical parameters, obtained value for bottled drinking water showed less than SLS permitted level. However, in the case of microbial quality, some samples were showed colonies for both batches. Therefore, this study concluded that proper sanitation practices need to be followed in respective bottled water producing industries to ensure safe drinking water for all.

Effect of Wax Coating, LDPE Packaging and Storage Conditions on Prolonging the Shelf Life of Fresh Lime (Citrus aurantifolia L.)

Fri, 14 Feb 2020 00:00:00 GMT

Effect of Wax Coating, LDPE Packaging and Storage Conditions on Prolonging the Shelf Life of Fresh Lime (Citrus aurantifolia L.) Premathilake, R.W.N.; Arunakumara, K.K.I.U.; Wijewardhane, M.N.A. The study was conducted to assess the effect of wax coating and LDPE packaging on shelf life, physical appearance and internal quality parameters of lime fruits under cold storage and ambient conditions. Mature green lime fruits were harvested from commercial orchards at Anuradhapura and brought to laboratory within 30 minutes. 1200 fresh lime fruits were divided in to 8 lots and each lot contains 150 Lime fruits. Four lots of fruits were dipped in bio-wax formulation for about one minute. Other four lots were remaining without application of bio wax. Four lots, representing two lots each from with and without bio-wax application were packed using LDPE packaging. The remaining four lots were kept without LDPE packaging. Four lots (with LDPE and without LDPE packaging under the each of bio-wax coating and without bio wax coating) were kept under cold storage (13oC ±2oC, RH 95%) and other four samples kept under ambient conditions (32oC ±2oC, RH 70%) in medium size plastic crates. Each treatment was replicated in 3 times. Percentage weight loss, percentage decay incidence, fruit quality characteristics (titratable acidity, total soluble solids, fruit firmness and pH), visual quality and peel colour were recorded in weekly interval. Combination of wax coating, LDPE packaging and cold storage was the most effective treatment in maintaining the quality of lime fruits. This effect was significant (p<0.05) as indicated by the lowest percentage weight loss (14.56%) during 8 weeks of storage period than the other treatment combinations. Although weight, firmness, pH, total soluble solids of this treatment remained within average values during storage period while 73% of fruits in marketable condition after 60 days of storage, the peel colour change from green to yellow after 30 days. Quality attributes such as firmness, pH, titratable acidity and total soluble solids had significant difference with other treatments (p≤0.05). Limes can be stored only 7 days without applying any preservation method in ambient condition while combination of wax coating, LDPE packaging and cold storage method extend the shelf-life of lime fruits up to 60 days.

Development and Quality Evaluation of Instant Green Smoothie Powder

Fri, 14 Feb 2020 00:00:00 GMT

Development and Quality Evaluation of Instant Green Smoothie Powder Dilrukshi, S.H.B.; Senarath, H.P.S. Fruits and vegetables are rich in more nutrients and phytochemicals that can be given enormous healthy and nutritional benefits. The world health organization recommends to consume ≥ 5 portions of fruits and vegetables per day. But, only 17.5% of Sri Lankan adults consume suggested value. Therefore, the production of a healthy and convenient product may increase the consumption of fruits and vegetables. The aim of this study was to develop an instant green smoothie powder as a more convenient product using locally available fruits and green leafy vegetables and to evaluate the quality parameters of the powder. Four fruits and three green leafy vegetables were selected to develop fresh green smoothie. The best formulation of the green smoothie was selected by conducting a sensory evaluation using 30 semi-trained panelists. The selected formulation was freeze-dried to obtain instant green smoothie powder. The resulted powder was analyzed for proximate composition; protein (2.67 ± 0.02%), fat (1.96 ± 0.01%), moisture (4.82 ± 0.01%), ash (1.22 ± 0.02%), and fiber (28.57 ± 0.01%) using AOAC 2000 method. Reconstituted green smoothie showed physicochemical properties such as pH of 4.21 ± 0.04, titratable acidity of 0.213 ± 0.04 g/100ml, total soluble solid of 12.330 ± 0.01%), and water activity of 0.17 ± 0.01. The powder properties revealed that the powder has very good (based on Carr Index) flow ability (6.665 ± 2.35) and it has low (based on Hausner ratio) cohesiveness (1.0713 ± 0.03). The solubility (94.71 ± 2.43) of the powder complied with the SLS Standards (668: 1984). The instant green smoothie contained 129.5 ppm of vitamin C content and 107.25 ± 3.32 Ascorbic Acid Equivalent mg/g of total antioxidant capacity. The powder was microbiologically stable (only 1log CFU/mL of total plate counts). The water activity of the powder was significantly (p<0.05) increased, but the pH and total plate count were not significantly (p>0.05) increased during the five weeks of storage at room temperature in vacuum package. This instant powder can be introduced as the more convenient and healthy choice for the consumers, which has higher crude fiber content, better microbiological stability and very good powder properties.

A Comparative Study on the Nutritional and Sensory Qualities of Biscuits Supplemented with Brown Rice and White Rice Flour from Selected Rice Varieties

Fri, 14 Feb 2020 00:00:00 GMT

A Comparative Study on the Nutritional and Sensory Qualities of Biscuits Supplemented with Brown Rice and White Rice Flour from Selected Rice Varieties Wijerathna, S.N.T.A.R.; Mahendran, T.; Senarathna, B.M.K. Rice (Oryza sativa) is the staple food of Sri Lankans and more than 60% of the global population which directly supply more than 42% of calories consumed by the entire human population. As staple foods, rice provides a greater proportion of carbohydrate, dietary fiber and protein. In addition, rice is a rich source of vitamin B , vitamin E and minerals, such as calcium, magnesium, iron, zinc and phosphorus. Rice and rice products provide a large number of phytochemicals and antioxidants, which exert protection against gastrointestinal cancers and cardiovascular diseases. Therefore, a research was conducted to assess the nutritional and sensory qualities of biscuits supplemented with brown and white rice flour of selected varieties namely Suwandel, At 309 and Bg 94-1. Rice bran has better nutritional value therefore the biscuits were prepared using whole grain rice flour with 1:2 proportion of brown rice and white rice flour. For the preparation of biscuits, sugar and margarine were mixed to produce a creamy mixture. Then, the rice flour, baking powder, corn flour, margarine, sunflower oil, brown sugar, salt, and vanilla essence were added and thoroughly mixed to form a consistent hard dough. The dough was spread, cut into circular shapes of 4cm diameter and baked in an oven at 180℃ for 25 minutes. The baked products were stored in metallized laminated pouches under ambient conditions of 30℃ and 70-80% RH for 2 months. During the storage period, the biscuits were subjected to nutritional and sensory analysis at 2 weeks intervals. The sensory evaluation was carried out by 30 experienced panelists using a 7- point hedonic scale. Results revealed that the biscuits which were prepared with Suwandel obtained the highest overall acceptability value of 6.88+0.21 compared to other varieties. Nutritional analysis proved that the biscuits made with Suwandel rice variety had the highest fiber, protein and ash contents of 1.83%, 6.28% and 1.41%, respectively and Bg 94-1 variety poses the highest fat content of 12.3%. Based on the nutritional and sensory evaluation, biscuits prepared from Suwandel rice variety was considered as the best among the tested rice varieties.