Comparative evaluation of physical properties and aroma profile of carrot slices subjected to hot air and freeze drying

Rajkumar, Gopalan; Saravanan, S.; Galvão, Mércia de Sousa; Neta, Maria Terezinha Santos Leite; Sandes, Rafael Donizete Dutra; Mujumdar, Arun S.; Narain, Narendra

doi:10.1080/07373937.2016.1206925

Cited by 59 publications

(30 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Drying resulted in a decrease in limonene concentrations. The thermal degradation of limonene has been expressed in a previous study (Rajkumar et al, ). MWD samples had the highest limonene concentration.…”

Section: Resultsmentioning

confidence: 99%

Comparative evaluation of quality properties and volatile profiles of lemon peels subjected to different drying techniques

Tekgül

Baysal

2018

J Food Process Engineering

View full text Add to dashboard Cite

In this study, effects of different drying techniques (open‐air drying [AD], hot air drying [HAD], microwave drying [MWD], and freeze‐drying [FD]) on quality properties and volatile compound profiles in lemon peels were examined. For those purpose, water‐holding capacity, water activity, bulk density, color, pH, titratable acidity, total phenolic content, antioxidant activity, ascorbic acid content, total carotenoid content, and volatile compounds of dried lemon peels were determined. Among the drying methods, the highest retention of phenolics, ascorbic acid, and carotenoids were provided by FD. A total of 56 volatile compounds were identified in dried lemon peel powders. MWD samples contained the largest number of volatiles, whereas HAD samples had the highest volatile content. Principal component analysis on volatiles indicated that there is a convenient relation between the AD, HAD, and FD samples. Practical applications Different drying techniques play significant roles in the storage of fruits and vegetables. However, the effect of these methods on the quality of various foods is still not clear. This article indicates the effects of open‐air, hot air, microwave, and freeze‐drying methods on certain quality parameters and volatile compounds of lemon peels. The obtained data from the present study will provide valuable information for setting up industrial‐scale dryer systems for products with high volatile content. It will provide contribution to the improvement in food companies on their production conditions.

show abstract

Section: Resultsmentioning

confidence: 99%

Comparative evaluation of quality properties and volatile profiles of lemon peels subjected to different drying techniques

Tekgül

Baysal

2018

J Food Process Engineering

View full text Add to dashboard Cite

show abstract

“…The rehydration rate (RR) of the dried quince slices was obtained after weighing approximately 2.5 g of dried sample in glass beakers containing DW in a ratio of 1:30 (w/w) at 100°C for 10 min. Following soaking, the excessive water was taken off by absorbent paper, and samples were weighed, and the RR was calculated as follows (Rajkumar et al, ):

RR (() %) = \frac{{normalR}_{2}}{{normalR}_{1}} x 100

where R 1 and R 2 are constant for initial weight (g) and weight reached after water absorption (g) of the quince, respectively.…”

Section: Methodsmentioning

confidence: 99%

The effect of ultrasound pretreatment on quality attributes of freeze‐dried quince slices: Physical properties and bioactive compounds

Yıldız

İzli

2019

J Food Process Engineering

View full text Add to dashboard Cite

The study was conducted to examine the effect of ultrasound (US) pretreatment on physical and chemical/nutritional attributes of freeze-dried quince slices. The quince fruits were washed, hand-peeled and cut with a dimension of 1 cm (L) × 0.2 (W) cm × 1 cm (H). The quince samples were treated in an ultrasonic bath in three different times which were 10, 20, and 30 min. Untreated and ultrasonically pretreated quince samples were dried in a freeze dryer. Freeze-dried samples were analyzed in terms of physical properties such as shrinkage, rehydration, color, water activity, and hardness and bioactive compounds including total phenols, ascorbic acid, and antioxidant capacity. A significant difference was observed among untreated and ultrasonically pretreated quince samples. The freeze-dried quince slices treated with a US (especially 20 min-treatment) showed a higher preservation of bioactive compounds in addition to improved physical properties compared to the untreated quince samples. In overall, US pretreatment is a promising process as demonstrated in current research by its capability to better retain freeze-dried quince quality in terms of physical and chemical properties.

show abstract

“…The retention of ascorbic acid content (65.47 vs. 4.14-24.39 mg/100 g dm) and antioxidant capacity (1699.59 vs. 873.32-1148.86 mg trolox/100 g dm) was highest for freeze-dried tomatoes. Rajkumar et al [52] reported high rehydration ratio and aroma retention in freeze-dried carrots. In terms of shrinkage, carrots exposed to FD had lower shrinkage rate (20.83%) than HAD (35.53%).…”

Section: Vegetablesmentioning

confidence: 99%

Freeze-Drying of Plant-Based Foods

Bhatta

Janežić

Ratti

2020

Foods

185

View full text Add to dashboard Cite

Vacuum freeze-drying of biological materials is one of the best methods of water removal, with final products of highest quality. The solid state of water during freeze-drying protects the primary structure and the shape of the products with minimal volume reduction. In addition, the lower temperatures in the process allow maximal nutrient and bioactive compound retention. This technique has been successfully applied to diverse biological materials, such as meats, coffee, juices, dairy products, cells, and bacteria, and is standard practice for penicillin, hormones, blood plasma, vitamin preparations, etc. Despite its many advantages, having four to ten times more energy requirements than regular hot air drying, freeze-drying has always been recognized as the most expensive process for manufacturing a dehydrated product. The application of the freeze-drying process to plant-based foods has been traditionally dedicated to the production of space shuttle goods, military or extreme-sport foodstuffs, and specialty foods such as coffee or spices. Recently, the market for ‘natural’ and ‘organic’ products is, however, strongly growing as well as the consumer’s demand for foods with minimal processing and high quality. From this perspective, the market for freeze-dried plant-based foods is not only increasing but also diversifying. Freeze-dried fruits and vegetables chunks, pieces, or slices are nowadays majorly used in a wide range of food products such as confectionaries, morning cereals, soups, bakeries, meal boxes, etc. Instant drinks are prepared out of freeze-dried tea, coffee, or even from maple syrup enriched with polyphenol concentrated extracts from trees. The possibilities are endless. In this review, the application of freeze-drying to transform plant-based foods was analyzed, based on the recent research publications on the subject and personal unpublished data. The review is structured around the following related topics: latest applications of freeze-drying to plant-based foods, specific technological problems that could be found when freeze-drying such products (i.e., presence of cuticle; high sugar or lipid concentration), pretreatments and intensification technologies employed in freeze-drying of plant-based foods, and quality issues of these freeze-dried products.

show abstract

Comparative evaluation of physical properties and aroma profile of carrot slices subjected to hot air and freeze drying

Cited by 59 publications

References 27 publications

Comparative evaluation of quality properties and volatile profiles of lemon peels subjected to different drying techniques

Comparative evaluation of quality properties and volatile profiles of lemon peels subjected to different drying techniques

The effect of ultrasound pretreatment on quality attributes of freeze‐dried quince slices: Physical properties and bioactive compounds

Freeze-Drying of Plant-Based Foods

Contact Info

Product

Resources

About