A combination of digital camera, computer and graphic software can provide a less expensive and more versatile technique to determine the changes of colour on chocolate's surface in fat bloom assessment compared to instrumental colour measurement. Both techniques were applied and compared to measure the colour profiles at various locations on the surface of bloomed chocolates. Pearson correlation coefficients and sample paired t-test on whiteness index (WI) and L*a*b* values were calculated. The value of WI of chocolate samples from instrumental technique was in the range of 35.8-44.3 with a coefficient of variance (CV) ranging from 0.0 to 0.9%. Meanwhile, digital image technique gave a WI value ranging from 35.1 to 45.1 with a CV from 0.1 to 14.2%, respectively. A highly significant correlation was found for the means of WI (R21/4 0.821) and L* (R2 1/4 0.788) values between instrumental and digital image technique. b* value of digital image also had significant correlation with the instrumental data (R21/4 0.756). However, there were significantly different measurements in the values obtained (p<0.001) by both techniques. Thus, b* as well as a* values could not be used as a colour indicator in this study. The results suggested that though the digital image provided good measurement of WI and L*, the colour measurements of digital image were less precise as compared to the instrumental technique, therefore results from the digital image should be interpreted with caution.

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Pineapple (Ananas comosus (L.) Merr.) being a non climacteric fruit, its flavor and sugar content does not increase after harvesting. Thus, the maturity stage at harvesting affects the quality of pineapples after harvesting. This study was conducted to compare the quality parameters at four different ripening stages of pineapple (cultivar Mauritius-Queen type) and their effect on sensory properties after dehydration. Pineapples were harvested at dark green, 50% yellow, 75% yellow and 100% yellow color stages. Total Soluble Solid (TSS) content, Titratable Acidity (TA), TSS/TA ratio, pH, Fruit firmness, L*,a*,b* and hue angle were quantified in fresh samples and the appearance, texture, taste, odor, color and overall acceptability were evaluated in dehydrated samples at each ripening stage. The ripening stage had a significant (P<0.05) effect on selected quality parameters of fresh pineapples. Highest TSS content of 17.75±0.67 was observed in 100% yellow stage whereas the lowest was observed in dark green stage (15.75±0.48). In contrast, the highest firmness was observed in dark green stage (27.47±6.4 N) while the lowest was in 100% yellow stage (12.01±1.17 N). Lowest pH and highest TA were observed in dark green stage while the highest pH and lowest TA were observed in 100% yellow stage with values of 3.49±0.06, 0.82±0.02, 3.74±0.01 and 0.78±0.02, respectively. Sensory evaluation revealed that 75% yellow stage is the optimum ripening stage for dehydration of pineapple (cultivar Mauritius-Queen type) with significantly greater sensory evaluation ranks compared to other stages.

The necessity for food traceability has been increased over the years with the expansion of food supply chains globally over these years due to stringent of food safety regulations. Enhancing the access to quality food safely is one of the essential requirements of food supply chain traceability. Conversely, significant percentages of postharvest losses available especially in developing countries due to poor supply chain and logistics practices thereby threatening food security. Unless there is a possibility to trace the Supply chain, it is difficult to take remedial actions. When it comes to Sri Lanka, currently it is harder to have the traceability in most of the foods supply chains commonly on most of the elementary supply chains such as fruits and vegetables. This has led to postharvest losses since it is harder to identify when and where damages occur, who are accountable, harvested and transient times, supply demand mismatch too. Therefore, this paper aims to investigate the feasibility of tracing of fruit and vegetable supply chain in Sri Lanka and contribute theoretically to facilitate authorities and decision makers for future traceability improvement. Availability of secondary information on fruits and vegetables traceability was examined referring to government agencies. Basic structure of supply chain was identified based on secondary data and a case study was conducted based on supply chains linked to Thambuththegama and Keppetipola Dedicated Economic Centers to gather primary data. To quantify the feasibility of tracing, a feasibility index was developed. Developed index was used to assess the feasibility towards improved traceability of selected chains where it can be applied for other food and non-food supply chains as well. The feasibility index can be used for other fruits and vegetables supply chains too to assess the feasibility prior to implementation of a traceability system. Furthermore, it can be used for non-food supply chains with some modifications. Analysis revealed that poor feasibility of wholesalers compared to farmers and retailers. Product identification technologies, awareness and willingness for traceability improvement were ranged low to fair for all the entity categories. Hence, enhancement of record-keeping and information sharing, adopting product identification and quality measurement technologies, and strengthening of legislation were identified as key improvements for enhanced fruits and vegetable traceability and efficient postharvest management of studied supply chains

Purpose : Guava cultivations are spreading rapidly among Sri Lankan farmers, especially in dry zone. Surplus production is observed in certain months of the year. Dehydration can be used as an effective method to preserve the surplus. During dehydration, browning of guava impairs the quality of the final product. This experiment was carried out to find out the most effective browning inhibitor.Research Method : Four treatments were used prior to dehydration namely, Citric acid (CA), Ascorbic acid (AA), Sodium metabisulfite (SMS) and Blanching for 2 minute in 60 °C (BL) as twenty different combinations. The L*, a* and b* values, were recorded. Colour differences with fresh slices, total colour difference (TCD) and browning index (BI) were calculated.Findings : L*, a* and b* values were significantly different (P<0.05) among treatments. The lowest L* value difference was observed in CA 0.3% with BL (3.18±0.7). Lowest total colour difference and the lowest browning index were observed in blanching treatment followed by CA 0.3% with BL. Whereas the highest TCD was in control sample (21.86 ± 2.75) and the highest BI was in SMS 0.5% with BL (55.38±8.59). Results revealed that out of the treatments under study, BL only and CA 0.3% with BL were the most effective solutions to overcome the browning of guava during dehydration.Originality/ Value : Research findings could be used in guava dehydration industry to preserve the colour and visual quality of the dehydrated products which will increase the consumer acceptability and demand thereby reducing postharvest losses.