Freezing of fresh Barhi dates for quality preservation during frozen storage

Abstract

Fresh harvested dates are perishable and there is a need for extending their shelf life while preserving their fresh like quality characteristics. This study evaluates three different freezing methods, namely cryogenic freezing (CF) using liquid nitrogen; individual quick freezing (IQF) and conventional slow freezing (CSF) in preserving the quality and stability of dates during frozen storage. Fresh dates were frozen utilizing the three methods. The produced frozen dates were frozen stored for nine months. The color values, textural parameters, and nutrition qualities were measured for fresh dates before freezing and for the frozen dates every three months during the frozen storage. The frozen dates’ color values were affected by the freezing method and the frozen storage period. There are substantial differences in the quality of the frozen fruits in favor of cryogenic freezing followed by individual quick freezing compared to the conventional slow freezing. The results revealed large disparity among the times of freezing of the three methods. The freezing time accounted to 10 min for CF, and around 80 min for IQF, and 1800 min for CSF method.

Evaluation of sensory and texture profile analysis properties of stored Khalal Barhi dates nondestructively using Vis/NIR spectroscopy

“…The results showed that the stage of maturity (at different harvesting time) significantly ( p ≤ .05) influenced all studied physical properties. The data are comparable to Alhamdan, Hassan, Alkahtani, Abdelkarim, and Younis () work with slight variations. Those variations conceivably might be attributed to the age of palm trees, location, and harvesting operations.…”

Effects of Gibberellic Acid (GA3) and Salicylic Acid (SA) postharvest treatments on the quality of fresh Barhi dates at different ripening levels in the Khalal maturity stage during controlled atmosphere storage

“…The reduction in hardness, elasticity, and chewiness, during ripening may be due to breakdown of insoluble solids into soluble solids or by cellular breakdown leading to membrane porousness. Equivalent results of the efficacy of GA 3 in preserving fruit texture are stated by other authors for different fruits [9,11,[33][34][35][36] . Preservation of fruit texture by SA pretreatment has been identified earlier in several fruits [37,38] .…”

“…Fruit samples were compressed with a rod velocity of 1.5 mm/s to a depth of 5 mm. The obtained force-time deformation curves were used to calculate the following textural parameters: hardness, elasticity and chewiness [11] .…”

“…Barhi fruits at the Khalal stage are more favorable and sold at higher rates compared to the Rutab and Tamer stages, however, the time for effective marketing is too short. A critical challenge is the preservation of the high quality of Barhi dates for the longest possible period after harvesting and during the marketing process [10,11] .…”

Researches on the freezing of blueberries and green bean pods using an experimental model of a fast freezing equipment

“…In order to extend the permissible period of storage and marketing of perishable foodstuffs, a number of conservation methods and techniques can be applied [1][2][3][4][5][6]: preservation by using low temperatures (refrigeration, freezing, modified atmosphere); preservation by using high temperatures (pasteurization, sterilization); conservation by reducing the water content of the product (dehydration, concentration); preservation by the use of inhibitors of depreciation phenomena (natural antimicrobials, bacteriocins, sugar addition, acidification, chemical preservatives etc. ); preservation by unconventional methods (ionizing radiation, high pressure, high voltage electrical impulses, non-ionizing radiation, ozone, ultrasound, photodynamics, etc.).…”