Review Article Journal of Advanced Research in Food Science and Nutrition (ISSN 2582 3892) Copyright (c) 2021 Advanced Research Publications Journal of Advanced Research in Food Science and Nutrition[.]
Journal of Advanced Research in Food Science and Nutrition Volume 4, Issue - 2021, Pg No 10-14 Peer Reviewed Journal Review Article Quality Characteristics of Dried Queen Pineapple by Cold Air Drying Combined with Ultrasound Pretreatment Process Nguyen Thi Ngan1, Nguyen Thanh Luan2, Tran Van Khanh3, Nguyen Quoc Cuong4 Faculty of Health Sciences and Finance - Accounting, Dong Nai Technology University, Dong Nai, Vietnam Faculty of Technology, Dong Nai Technology University, Dong Nai, Viet Nam 1,2,3 I N F O A B S T R A C T Corresponding Author: Nguyen Thi Ngan, Faculty of Health Sciences and Finance - Accounting, Dong Nai Technology University, Dong Nai, Vietnam E-mail Id: nguyenthingan@dntu.edu.vn Orcid Id: https://orcid.org/0000-0001-6416-2568 How to cite this article: Ngan NT, Luan NT, Khanh TV et al Quality Characteristics of Dried Queen Pineapple by Cold Air Drying Combined with Ultrasound Pretreatment Process J Adv Res Food Sci Nutr 2021; 4(1): 10-14 The main purpose of this study to improve the product quality of dried Queen Pineapple, a new strategy utilizing ultrasound pretreatment combined with cold air drying This research was conducted on pineapple fruits (pineapple Queen Long Thanh, Dong Nai) with high sugar content of about 16-18 °brix, especially vitamin C, the highest rate was 47.8mg/100g Determining the appropriate ripeness is maturity of pineapple fruit with maturity of about 10 - 20% of the surface of pineapple skin with yellowish green color, with this ripeness, the product will give best quality For the study, we examined pineapple slices with 3mm,5mm, 7mm were first pretreatment with ultrasonic for 30 minutes, subjected to osmotic dehydration process using sugar syrup of 20 °Brix, 25 °Brix and 30 °Brix for hours at room temperature Pineapple slices were drying at °C about 1800 minutes until moisture content was 14 ± 0.1% When comparing the quality of two methods of conventional drying and cold air drying, the method of cold air drying food is the best method of drying food to retain vitamin C, which is the most easily lost during the drying process, but the cold air drying method still preserve very high content of vitamin C, for dried pineapple products is 30 mg/ 100g and improve the color of the final product Date of Submission: 2021-04-14 Date of Acceptance: 2021-05-30 Keywords: Pineapple fruit, Cold air drying, Ultrasonic, Osmotic Introduction Fruits and vegetables are a good source of important essential nutrients such as vitamins, minerals and fiber In Vietnam, the pineapple varieties are currently grown in Ananas comosus species This species is divided into groups including main groups: Cayen, Queen and Spanish pineapple Pineapple is one of the most important commercial fruit crops with several health benefits.10 It is low in fat and cholesterol Pineapple is also a good source of vitamin B1, vitamin B6, copper and dietary fiber.7 Using pineapple could help to increase the immune system, aids digestion of proteins, reduce symptoms of the common cold and strengthens bones.14 Pineapple makes up a large amount of water (more than 80%), and so it is classified as perishable Many different products can be processed from pineapple like juices, squash, wines, jams, concentrates and powder.13 Drying is the most common method of food preservation Conventional air-drying is a simultaneous heat and mass transfer process, accompanied by phase change.2 Traditional drying methods often use high temperatures to dry out a lot of water, but with the cold air drying method combined Journal of Advanced Research in Food Science and Nutrition (ISSN: 2582-3892) Copyright (c) 2021: Advanced Research Publications Ngan NT et al J Adv Res Food Sci Nutr 2021; 4(1) 11 with ultrasonic permeation, the product will reduce loss of color, loss of nutrients, and structure With the purpose to effective conservation of nutrients, color, cold air drying is known for its low temperature and humidity Barbosa AF et al found that cold air drying could better preserve the product’s nutrients comparing with hot air drying.3 The pretreatment ultrasound process affects the energy of the drying process as well as the sugar content in the final product because according to Fernandes et al pretreatment ultrasound reduces sugar content by 21-52% but does not affect drying time.8 The ultrasonic pre-treatment involves the immersion of the fruit in water or in a hypertonic aqueous solution to which ultrasound is applied The advantage of using ultrasound is that the process can be carried out at ambient temperature and no heating is required, reducing the probability of food degradation.9 Studies on drying of fruits and vegetables have carried out ultrasound to assist osmotic dehydration15-17 and there have been many studies published involve with the implement of ultrasound on drying.19-21 However, there have not been many studies conducted on cold air drying combined with osmotic ultrasound, which has been successfully used in reducing moisture content to 14 ± 0.1% and maintaining the original product quality Material and Method Materials and Equipment Pineapples are bought at the garden house in Long Thanh Dong Nai, Vietnam Equipment Table Model LC-743H Temperature 0-10ºC Power Consumption (KW/h) 3.7kW/24h Electric 220V/50Hz Size (DxRxC) mm 610×610×1973 weight 158.7lbs Gas R134a/220g Wattage 285W Gas R134a/220g Methods The color and browning index measurement can be found in the literatures.11 Color was determined based on the CIELab system, a colorimeter (Colori5, USA) was used for dried pineapple slices immediately after drying The color values of the samples were expressed as L* (whiteness/ darkness), a* (redness/greenness), and b* (yellowness/ blueness) Total color difference (ΔE) was estimated by: Where Lo*, are represent the color values of the fresh pineapple slices samples, and L*, a*, and b* represent the color values of dried samples Five selected samples were repeated three times in each group Moisture content was estimated in the samples using A.O.A.C method.1 Five g of sample was weighed and transferred to pre-dried dish Weighed sample was dried in hot air oven at 105 °C The dish with dried sample was transferred to desiccators, cooled to room temperature and weighed The ascorbic acid determination was performed by the titrimetric method based on the reduction of the indicator 2, 6-dichlorophenolindophenol by the ascorbic acid as described in A.O.A.C.1 Statistical Analysis All analysis were performed in triplicate Statistical analysis were using statistical software Stargraphic 5.0 Prepare Material Pineapple selected materials and collect purchased at the garden of the same maturity (left two yellow eyes from the bottom of the left) Pineapples were left to ripen under normal laboratory conditions before being used for experiments Figure 1.Comparative status of agricultural sector to the overall economic growth of Nepal After that, the pineapple was removed at both ends, only the middle part of the pineapple was used for the experiment, when the concentration of dissolved dry matter ISSN: 2582-3892 Ngan NT et al J Adv Res Food Sci Nutr 2021; 4(1) 12 ranged from 13-18 °Brix Next, the pineapple was peeled, gently cut into slices of different thicknesses, gently wipe the surface of the pin with dry tissue to prepare for the experiment and mixed with syrup solution in Ultrasonic Machine in period time and drying in equipment at 5°C at wind speed m/s Result and Discussion Investigate the Influence of Ripeness on Product Quality after Drying Surveying material thickness: slice of pineapple mm, mm and mm In Figure 3, we could see that the moisture loss of the material over each drying time of samples, with samples and here having reached the optimum moisture content within 24 hours Particularly for sample (7 mm) because the size is thicker than other samples, the drying process will take longer to achieve results than the other samples In terms of the panel parameters and sensory assessments, we Table 2.Color measurement results Form Moisture content (%) Ripeness Color Drying time (hours) ∆*L ∆*a ∆*b ∆E * 14.6% 55.09 10.39 35.15 65.69 24 Ripeness 14.2% 59.06 11.78 35.75 69.73 18 Ripeness 17% 54.09 10.45 34.15 64.55 30 Figure 2.Picture of product after drying In Table shows that three samples dried at the same period temperature, the moisture content of each sample is not significantly different, but we can see at the ripeness of sample (ripeness 2) drying times to achieve a constant moisture content than the rest of the sample about hours In ripeness about the color, we can also see in the table that it is clear that the color ratio is not too different, but the ripeness has a higher score of ∆ * L and ∆ * b, showing the brightness and golden ratio of the sample Higher than the rest of the samples, proving that ripeness has the same color as the fresh pineapple The drying time of the ripeness was the lowest according to Table after only 18 hours reaching 14% moisture So we have decided ripeness is optimal for inclusion in the experiments to follow can see that with 5mm size the sensory requirements and the most drying time as this sample product showed great beauty and moisture content request As for the number sample (3 mm), we did not choose because the sensory evaluation committee commented that this sample is too thin, the shape is not good shape Therefore, in order to achieve the best results and the most beautiful product in terms of the most sensory value for the next experiments, we decided to use the 2nd model of size mm with 1680 minutes to have the moisture content 14% Investigate the Effect of Osmotic Solution Figure 4.Drying curve of affecting brix of solution on drying time Figure 3.Picture of product after drying ISSN: 2582-3892 In Figure 4, we observe the graph of drying curve of concentrations We found that the concentration of 20 °Brix and 25 °Brix had quite similar drying speed, however, the concentration of Brix 20 achieved the required moisture content faster during the experimental observation period Regarding the concentration of 30 °Brix, we see that the drying speed is quite fast and it only takes 24 hours to reach the optimum moisture However, in terms of organoleptic Ngan NT et al J Adv Res Food Sci Nutr 2021; 4(1) 13 aspects, the Brix 30 concentration was too sweet compared to the other two samples, because the tastes of today’s consumers not like to eat too sweet, we decided to achieve moisture Optimize and keep consumer needs, we choose 25 °Brix concentration to perform experiments Compare the Quality of Dried Pineapple between Traditional Drying 60 °C and Cold Air Drying °C Observe physicochemical indicators in Table we can see that the ∆*L index of the dark to light color index and the ∆ *b index of green to yellow color of cold method have higher brightness and yellow color than that of thermal drying method This tells us that the method of cold drying retains pineapple’s color better than the method of heat drying In Figure and 6, we can see that the moisture loss in the two drying methods has a significant difference With the same pretreatment method, the traditional drying method achieved the required moisture content in 16 hours compared to the 24-hour cold air drying method For the traditional drying method, the outstanding advantage is that the drying time is shorter than that of the cold drying method, but the color of the final product no longer preserves the color of the pineapple as well as vitamin C content is lower than As for the cold air drying method as we all see the advantage of this method is to retain the color of fresh pineapple with the best sensory value, and vitamin C content is higher than Conclusion The results of the study showed that the appropriate ripeness is the second maturity of pineapple with maturity of about 10 - 20% of the surface of pineapple skin with yellowish green color, light yellow flesh With this ripeness, the product will give good quality, the optimal size for the survey is mm, the best osmotic concentration for the product is 25° Brix, the ultrasonic time of 30 minutes, temperature drying is 5°C will give the product time to dry The best quality is compared to the two methods of cold and heat drying The dried pineapple-based product still retains very high levels of vitamin C, for the dried pineapple product is 30 mg/100 g Figure 5.Cold air dry pineapple product References Figure 6.Traditional drying pineapple products AOAC Official Methods of Analysis of AOAC International 15th edn Association of Official Analytical Chemists, Washington D.C USA 1999 Barbanti D, Mastrocola D, Severine C Drying of plums A comparison among twelve cultivars Sciences des Aliments 1994; 14: 61-73 Barbosa AF, Sabaa-Srur DF, Maia JGS, et al Microbiological and sensory evaluation of Jambu (Acmella oleracea L.) dried by cold air circulation Food Science and Technology 2016; 36(1): 24-9 Duong DH Pineapple and its planting techniques: Part Table 3.Results of physicochemical properties of two drying methods Drying method Drying time (h) Moisture content (%) Vitamin C Cold air drying method 24 14.2 Traditional drying method 16 14 Color ∆ *L ∆ *a ∆ *b ∆E 30 mg/100 g 57.20 - 10.60 35.62 60.75 10 mg/100 g 67.57 -4.81 27.62 15.9 ISSN: 2582-3892 Ngan NT et al J Adv Res Food Sci Nutr 2021; 4(1) 1; Labour and Social Publisher: 2003; 22 Fernandes, Fabiano AN, Linhares Jr FE, et al Ultrasound as pre-treatment for drying of pineapple Ultrasonics Sonochemistry 2008; 15(6): 1049-54 Fernandes FAN, Gallão MI, Rodrigues S Effect of osmosis and ultrasound on pineapple cell tissue structure during dehydration Journal of Food Engineering 2009; 90(2): 186-90 Joy PP Benefits and Uses of Pineapple Research Station (Kerala Agricultural University, India 2010 Opalic M, Domitran Z, Komes D, et al The effect of ultrasound pre-treatment and air drying on the quality of dried apples Czech J Food Sci 2009; 27 Mason JP, Paniwnyk LL The uses of ultrasound in food technology Ultrasonics Sonochemistry 1996; 3: S253-6 10 Ramallo LA, Mascheroni RH Quality evaluation of pineapple fruit during drying process Food and Bioproducts Processing 2012; 90(2): 275-83 11 Zeng Y, Liu Y, Zhang J, et al Effects of far-infrared radiation temperature on drying characteristics, water status, microstructure and quality of kiwifruit slices Journal of Food Measurement and Characterization 2019; 13(4): 3086-96 12 Mauer LJ, Bradley RL Moisture and total solids analysis Food analysis, Springer 2017, pp.257-286 13 Pineapple India, 2012 C-26/3, Half Nagarjan, Dimapur, Nagaland 797112 14 Lobo MG, Paul RE Handbook of pineapple technology: production, postharvest science, processing and nutrition John Wiley & Sons 2017 15 Simal S, Benedito J, Sánchez ES, et al Use of ultrasound to increase mass transport rates during osmotic dehydration Journal of Food Engineering 1998; 36(3): 323-36 16 Cárcel JA, García-Pérez, JV, Riera E, et al Influence of high-intensity ultrasound on drying kinetics of persimmon Drying Technology 2007; 25(1): 185-93 17 Cárcel JA, Benedito J, Rosselló C, et al Influence of ultrasound intensity on mass transfer in apple immersed in a sucrose solution Journal of Food Engineering 2007; 78(2): 472- 18 Rodrigues S, Fernandes FA Ultrasound as pre-treatment for drying of fruits: Dehydration of banana Journal of Food Engineering 2007; 82(2): 261-7 19 Rodrigues S, Fernandes FA Use of ultrasound as pretreatment for dehydration of melons Drying Technology 2007; 25(10): 1791-6 20 Fernandes FA, Oliveira FI, Rodrigues S Use of ultrasound for dehydration of papayas Food and Bioprocess Technology 2008; 1(4): 339-45 21 Taiwo KA, Eshtiaghi MN, Ade‐Omowaye BI, et al Osmotic dehydration of strawberry halves: influence of osmotic agents and pretreatment methods on mass ISSN: 2582-3892 14 transfer and product characteristics International Journal of Food Science & Technology 2003; 38(6): 693-707 ... al found that cold air drying could better preserve the product’s nutrients comparing with hot air drying. 3 The pretreatment ultrasound process affects the energy of the drying process as well... C, for the dried pineapple product is 30 mg/100 g Figure 5 .Cold air dry pineapple product References Figure 6.Traditional drying pineapple products AOAC Official Methods of Analysis of AOAC International... ∆ *b index of green to yellow color of cold method have higher brightness and yellow color than that of thermal drying method This tells us that the method of cold drying retains pineapple? ??s