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یکی از محصولات جانبی خرما، پودر خرما می‌باشد که کاربردهای متعددی در صنایع غذایی دارد. مشکل اصلی پودر میوه‌ها چسبندگی طی خشک کردن، انتقال و نگهداری پودر است. برای جلوگیری از چسبندگی و کلوخه ای شدن پودر خرما، مالتودکسترین در سه غلظت (35، 45 و 55%) به‌عنوان ماده کمکی در خشک کردن و سیلیکون دی اکسید در سه غلظت (صفر، 75/0 و 5/1%) به‌عنوان ماده ضدکلوخه شدن به خمیر خرما قبل از خشک شدن اضافه شد. نمونه‌ها در سه دمای 50، 60 و70 درجه سانتی‌گراد خشک شدند. خواص فیزیکوشیمیایی و حرارتی پودر خرما شامل رطوبت، دانسیته توده، گرمای ویژه و دمای انتقال شیشه‌ای اندازه‌گیری شدند. نتایج نشان داد که افزایش غلظت مالتودکسترین سبب افزایش پارامترهای دانسیته، L* و دمای تغییر شیشه‌ای گردید ولی رطوبت پودر، مقدار a* و گرمای ویژه کاهش یافت. افزایش میزان سیلیکون دی اکسید سبب افزایش رطوبت، دانسیته و کاهش L* گردید. اثرات متقابل دما و مالتودکسترین و نیز دما و سیلیکون دی اکسید سبب کاهش رطوبت خرما، افزایش دانسیته، کاهش L* و a* و افزایش b* گردید. ترموگرام‌های پودر خرما نشان دهنده وجود ساختمان نیمه بلوری در پودر خرما بود. براساس نتایج، بهترین شرایط برای تهیه پودر خرما دمای ℃70، 55% مالتو دکسترین و 75/0% سیلیکون دی اکسید بود.

In this study some physical and geometrical properties of 11 superior apricot genotypes were determined. These properties such as respiration rate, Mass, fruit dimensions, perimeter, surface area, volume, geometric mean diameter, projected area, shape factor, circularity, compact factor, length to width ratio, length to thickness ratio, and length to mass ratio were measured at harvesting moisture content ranging from 75.19 to 87.67 %. Then the correlation among average values of the attributes was performed and the genotypes were classified using principal component analysis (PCA). The results showed that all the genotypes had significant differences in terms of all the studied attributes (P<0.01). There was a significant and positive correlation between fruit length and weight and fruit length and moisture content. Fruit shape factor and compression factor showed a positive and significant correlation, while these attributes had negative and significant correlations with circularity. This study showed that Iranian apricot genotypes could be discriminated by differences in their geometrical characteristics using principal component analysis. Based on the PCA results, the first two components account for the most of the variation in the data (91%) and five distinct groups were observed. Overall, the results of this study can be beneficial for the design of equipment for harvesting, transportation, separating, packaging, and processing of apricot fruit. [ABSTRACT FROM AUTHOR]

In this study, 23 local genotypes of sour cherry from collection in Meshkin Dasht-Karaj in terms of physical and chemical characteristics including weight, flesh to core ratio, firmness, total soluble solids, dry matter content, titratable acidity, pH, flavour index, respiration rate, color indices of fruits and juices (L*, b*, a*, Hue and Chroma) and their correlations were examined. The results showed that all genotypes had significant differences (p ≤ 0.05) in terms of the studied characteristics. Based on the correlations in the color indices, a* index alone can be used to evaluate the red color differences of various genotypes. According to the results, genotypes of KB-100, KB-450, and KB-213 with suitable characteristics such as weight (>2.8 g), flesh to core ratio (>8.5), flavour index (>9.5) and acidity (<1.75%) are more suitable for fresh consumption and genotypes of KB-232 and KB-247 with suitable weight (>3.7 g), dry matter content (>15%) and respiration rate (<9000 mg CO2/kg.hr) are more applicable for processing. Also, genotypes with high acidity (>3%) such as KB-157, KB-121, KB-234, and KB-152 are more suitable for pickling and fruit roll-up processing. Genotypes with high dry matter content (>21%) and intense redness (a*<9 for skin and a*<16 for fruit juice) such as KB-136 and KB-449 are more suitable for the production of powder, dried sour cherries, syrup and nectar. Late harvested genotypes with firmness (>6N) such as KB-343 and KB-353 are also recommended for compote and jam processing, respectively. [ABSTRACT FROM AUTHOR]

Fresh fig is a highly perishable fruit with a very short storage life. Therefore, drying is the most common method for fig preservation. Changes in water content during storage may lead to undesired physical changes in dried fig which is of great importance in its structure and quality. The objective of this study was to assess the effect of water on the physical properties of dried fig, using glass transition temperature (Tg). Tg, melting temperature (Tm) and the melting enthalpy (ΔH) of dried figs at different moisture contents were measured using differential scanning calorimetry (DSC). DSC thermogram showed that dried fig has a semi-crystalline structure. Tg and Tm decreased while ΔH associated with the melting of the ordered structure increased with increasing moisture content of fig. The results showed that water is a strong plasticizer for dried fig and reduced flesh firmness of fig significantly. Measuring color differences of dried fig at different moisture contents showed that by increasing water, fig flesh became darker significantly. Changes in texture, color, and crystallinity of the dried fig as a function of moisture were assessed using temperature difference (ΔT) between the fig temperature (T) and Tg. By increasing ΔT, the rate of firmness reduction, ΔE value, and the extent of crystallinity increased. [ABSTRACT FROM AUTHOR]

Wheat grain is commonly stored for a period of several months from harvest up to processing. Duringstorage grain can experience variations in composition and quality, especially if ambient conditions areunfavorable.In this study,First, accelerated aging of freshly harvested wheat grainswas carried out by increasing moisture content 16, 18 and 20% and keeping the samples in different temperatures 30, 40 and 50°C for different periods 2, 5 and 8 days.Samples were then milled and physicochemical properties including moisture content, protein, ash, wet gluten, pH and falling number were determined. Response surface methodology with the central composite design was applied to minimize total numbers of experimental runs and to determine the significance of the factors.Results showed that increasing storage temperature and time resulted in increasing protein, falling number, and ash, while wet gluten, pH and moisture content decreased. By increasing moisture content, wet gluten, protein, ash and falling number decreased while moisture content and pH increased. Optimization using response surface methodology showed that the optimum condition for accelerated aging of wheat grain contained 16% moisture content, storage temperature of 30°C for 2.87 days. [ABSTRACT FROM AUTHOR]