Effect of drying temperature, airflow rate and flower types on dried saffron flower quality

The separating of saffron stigma from fresh flowers is the most important and the most difficult step of saffron harvesting. The separating of saffron stigma is done with the hand labor, and it have time-consuming and costly. The saffron flowers will be decay if separating of saffron stigma is not done quickly.  Drying is one method of keeping saffron. The dried saffron flowers have the higher shelf life, and there have more time for separating of stigma. The main object of this study was to determine the best saffron flower drying method. Therefore, the effect of variables including drying temperature in three levels (40, 50 and 60 °C), airflow rate in two levels (0.5 and 1 m/s) and three levels of flowers (buds, semi opened and fully opened) were investigated on the amount of crocin (stigma color), saffronal (fragrance) and picrocrocin (bitter taste). The results showed that the amount of crocin decreased and the amount of saffronal increased with increasing of drying temperature. The best conditions for flowers drying were obtained with 50 °C drying temperature and 0.5 m/s airflow rate. The dried saffron flower buds had the higher amount of saffronal than dried flowers of semi opened and fully opened.

Effect of coating and modified atmosphere packaging on the characteristics of fresh- cut melon during storage

هدف از این پژوهش بررسی اثر کیتوزان، تیمول و اتمسفر تغییر یافته بر ویژگی‌های فیزیکوشیمیایی، حسی و میکروبی خربزه تازه برش‌خورده بود. بدین منظور،‌ برش‌های خربزه‌ در محلول حاوی درصدهای مختلف کیتوزان (صفر، 1 و 2%) و تیمول (صفر، 25/0 و‌ 5/0%) به مدت‌2 دقیقه غوطه‌ور شدند. برش‌های تازه میوه پس از پوشش‌دهی و حذف محلول‌های اضافی و نمونه شاهد‌ (پوشش‌داده نشده) در اتمسفر تغییریافته (10% دی‌اکسید‌کربن) و اتمسفر طبیعی بسته‌بندی و به مدت 8 روز در دمایC ͦͦ 4 نگهداری شدند. نتایج بیانگر افزایش میزان دی‌اکسید‌کربن و کاهش اکسیژن در بسته‌بندی تحت اتمسفر اصلاح شده و اتمسفر طبیعی همگام با افزایش دوره ماندگاری بود. اما در نمونه‌های پوشش‌دهی شده با کیتوزان و تیمول شدت کاهش اکسیژن و افزایش دی‌اکسیدکربن کمتر از نمونة شاهد بود. در پایان 8 روز نگهداری، افت وزنی در نمونه‌های پوشش‌دهی شده با کیتوزان و تیمول و نگهداری شده تحت اتمسفر تغییر یافته بسیار کمتراز نمونه شاهد بود (34/0% در مقایسه با 60/13%). افزایش غلظت کیتوزان و بسته‌بندی تحت اتمسفر تغییر یافته سبب افزایش حفظ میزان مواد جامد محلول، اسید قابل تیتراسیون، اسید اسکوربیک و سفتی بافت برش‌های خربزه شد، اما افزایش غلظت تیمول تاثیر معنی‌داری بر این ویژگی‌های کیفی نداشت. شاخص-های رنگی میزان سبزی- قرمزی (a*)، میزان آبی- زردی (b*)، میزان روشنایی (L*) و شاخص قهوه‌ای شدن (BI) نیز تحت تاثیر نوع بسته‌بندی و غلظت کیتوزان قرار گرفتند، اما، تیمار با تیمول بر شاخص‌های رنگی برش خربزه تاثیر معنی‌داری نداشت. اثر متقابل غلظت کیتوزان و غلظت اسانس نشان داد که برش‌های خربزه تیمار شده با غلظت 1% کیتوزان و غلظت‌های 25/0 و 5/0% تیمول دارای کمترین میزان بار میکروبی بودند. پوشش‌دهی با کیتوزان و تیمول و هم‌چنین نوع بسته‌بندی بر همه صفات حسی برش‌های خربزه (تاثیر معنی‌داری داشت (05/0 P<)؛ و ارزیابان در پذیرش کلی، غلظت 1%کیتوزان را بر غلظت 2% ترجیح دادند

Investigating the physicochemical, sensory and microbial properties of plant-based protein products (meat-free burgers) formulated using various Vicia ervilia (L.) Willd. protein isolates

The present study investigated the effect of using various protein isolates of Vicia ervilia (L.) Willd. (Bitter vetch; Family: Fabaceae) in formulating plant burgers on physicochemical, sensory and microbial properties of the resulting plant-based protein products. The results indicated that the plant-based protein products in the formulation of which protein isolates produced based on salt extraction methods were used, had higher rates of protein, fat and oil. On the contrary, they had lower rates of carbohydrate and moisture in contrast to the plant-based protein products formulated using protein isolates produced based on isoelectric precipitation methods. The reason for the high amount of fat and protein in these treatments can be attributed to the isolates’ production conditions, high amount of oil diffused from the product in contrast to low oil retention and absorption capacity and low level of the measured moisture in comparison with the high protein content. In the current century, due to the uneven human population growth as well as the limited growth of animal resources, the debate about protein deficiency is particularly important in developing societies. Efforts for finding abundant and cheap herbal sources of protein have led to various researches regarding the use of some such less-known legumes in developing countries. In this regard, different protein isolates of Vicia ervilia have been used in the formulation of vegetable burgers to produce a new, inexpensive and productive plant protein product in the food industry

Optimization of ultrasound-assisted osmotic treatment of Aleo vera gel impregnated with grape pomace phenolic compounds using response surface methodology

This study was focused on investigating the use of pulsed ultrasound-assisted osmotic dehydration (UAOD) for enhancing the infusion of phenolic compounds extracted from grape pomace (GPx) to Aloe vera (Aloe barbadensis Miller,) gel (AVG) using response surface methodology (RSM) and produce a dehydrated product with high antioxidant content. Fresh AVG were initially immersed in a sucrose solution of 50° B with three levels of GPx (10, 20, and 30 v/v) and subjected to pulsed ultrasound (US) treatment with a probe of 2 cm diameter, two levels of ultrasound amplitude (UA) (50 and 100%), and three ultrasound treatment times (UT) (30, 135 and 210 min). The pulsed on and off times were set at 15 and 1 min, respectively. A multiple regression analysis was carried out to develop second-order polynomial models with high coefficients of determination value (R2 &gt; 0.81). The optimal conditions were obtained using the Design Expert software. The best condition obtained for the UAOD optimization was UA = 59%, 20% grape pomace extract in 50% sucrose, UT = 173 min to result in a moisture loss of 51.3 % (predicted 49.9%), solid gain of 4.3 % (5.0%), total phenolic contents of 30.5 mg/g (31.8%), and DPPH radical scavenging activity of 15.3% (15.0%). UAOD therefore appears to be a promising process for antioxidant incorporation and preparing added value product.

Effect of Cold Storage on Saffron Flowers Shelf Life and Dried Stigma Quality

ABSTRACT Saffron (Crocus sativus L.) is a valuable crop in Iran and worldwide. Due to a rising production rate of saffron flowers and limitation of harvesting time, the best storage conditions should be determined. In this research, saffron flowers were harvested at semi-bloom form stage, and placed in plastic baskets, in two different thickness accumulations (10 and 15 cm). The flowers were stored at 0, 4, 8 and 21˚C for after 2, 4, 7, 14 and 21 days. During storage period, weight loss percentage was calculated. In addition, the stigmas were separated from the styles and dried in an oven at 60 o C. Bioactive compounds such as crocin, picrocrocin and safranal, and coliform enumeration were evaluated. The result indicated that weight loss percentage increased with increasing storage thickness, temperature and storage duration; however bioactive compounds reduced. The crocin and picrocrocin content were registered 298.73 and 100, respectively, when flowers were stored at 0 o C for 21 days. These values at 8 o C and 21 o C were not in the standard range; therefore these temperatures were not found suitable for flower storing. Although coliform contamination increased during storage days, the value was acceptable after 7 days. According to the results, it is recommended to store saffron flowers in basket with 10 cm Thickness Accumulation (TA) at 0 o C for 7 days

Comparison of sanitizing disinfectants on the physicochemical and microbial properties of onion puree (OP)

There is a growing demand for fresh cut, value-added and ready-to-use food in households, as well as for widespread use in retail, food services and the various food industries. Amongst vegetables, onions have many medicinal properties and can lead to health.This study evaluated the effect of disinfection methods including; T1: Nisin &amp; Citric acid (N+C), T2: Sodium hypochlorite (SH+S+C), T3: Calcium chloride+ Ascorbic acid+ Citric Acid (CC+AS+CA);T4: Control,during 21 days storage at 4°C on onion pure (OP). Each week, pH, soluble solids, acidity, weight loss, total phenolic compounds antioxidant activity and microbial tests (total microbial count, total molds and yeasts) were performed on the samples. Statistical analysis of the data by way of a completely randomized factorial design, demonstrated that in all treatments, the chemical properties of the storage period decreased, and the total number of living microbes and the total number of molds and yeast increased but, in T3(CC+AS+CA), the chemical properties, phenolic compounds, and the antioxidant activity were preserved and had the lowest microbial growth rate

Modelling the Chemical and Microbial Changes of Saffron Flower during Storage Using Artificial Neural Networks and Genetic Algorithm

Saffron, as the most expensive agricultural and pharmaceutical product of the world, has a special value among plants. Since the Saffron harvesting period is short, its storage for later processing requires understanding the most effective factors affecting the quality of saffron and its deterioration. Therefore the effects of reposition thickness, storage temperature and storage time of saffron flowers on its chemical parameters including crocin, safranal and picrocrocin values of saffron stigma and its microbial quality indicators including total count, coliform and mold contamination were modelled. This was done using multi-layer perceptron artificial neural network (ANN) and its structure and the learning parameters were optimized using genetic algorithm technique. The optimized MLP neural networkwas capable to predict the saffron quality characteristics during storage with coefficient of determinations higher than %94 and low error values (RMSE lower than 3.5 for all responses). The ANN model showed that reposition thickness has the lowest impact on chemical and microbial parameters deterioration while increasing storage temperature and time drastically increased loss of quality although the effect of storage time is lower than that of storage temperature.  Overall, keeping fresh saffron flowers at a low temperature near zero degrees centigrade is necessary for maximum retention of valuable chemical compounds and minimum microbial contamination development during saffron flower storage for further processing

Optimization of the pulsed electric field -assisted extraction of functional compounds from Nepeta binaludensis

Pulsed electric field (PEF) treatment was used for extracting effective components from Nepeta (Nepeta binaludensis Jamzad). A response surface method was used to investigate the effects of independent process variables (voltage of pulsed electric field (VPEF): 2, 4 and 6 KV/cm and number of pulsed electric field (NPEF): 20, 40 and 60 n) on the yield (Y) and antioxidant characteristics: total phenolic compounds (TPC), 1,1- diphenyl -2- picrylhydrazyl free radical scavenging (DPPHsc), ferric reducing-antioxidant power (FRAP), half  maximal of radical-scavenging activity (IC50) of Nepeta extract (aerial parts). According to Derringer’s desired function approach, the optimal conditions based on both individual and combinations of all process variables were VPEF 6KV/cm and NPEF 60 n. At this optimum condition, the Y, TPC, DPPHSC, FRAP, and IC50 of the extract were found to be 11.36%, 417.85 mg GA/g, 74.8%, 1688.53µmol Fe2+/g, and 0.32 mg/mL, respectively. The experimental values were in a good agreement with the predicted values. Also, the extract at optimal conditions of PEF (PEFopt-x) had a higher quantity of chlorogenic acid, caffeic acid, rutin, para-coumaric acid, rosemarinic acid, Kaempferol, and apigenin compared with solvent extract. The addition of PEFopt-x to the purified soybean oil at the levels of 6% increased oxidative stability index (2.65 h) close to butylated hydroxy toluene (2.78h)

Optimization of microencapsulation and stability evaluation of astaxanthin-rich shrimp shell extract

The goal of this research was to find the best way to use shrimp shell as a source of astaxanthin and as an agricultural waste in shrimp processing site. For this purpose, first shrimp shell extract was extracted with the assisting ultrasonic . Then it was encapsulated using different walls (modified starch and maltodextrin with hydrolysis degree of 7 and 20) and spray drying method. Wall composition design was performed using response surface method and simplex lattice design with augmented axial points in mixture design (14 wall compositions). Evaluation of physicochemical properties of microcapsules (moisture content, microencapsulating efficiency, astaxanthin content and antioxidant power) showed that the use of a mixture of maltodextrin and modified starch walls up to the center point of the triangular design (33.33%) improved the physicochemical properties compared to using of walls alone. Optimization of different wall concentrations for microencapsulation of shrimp shell extract containing astaxanthin using numerical and graphical optimization showed that the optimal wall composition containing 18.40% of maltodextrin with a hydrolysis degree7, 41.78% of modified starch and 39.81% of maltodextrin with a hydrolysis degree 20. Also, the stability of astaxanthin in microcapsules during 42 days of storage in different conditions of temperature (4 and 25ͦ C) and humidity (52 and 75%) showed that the amount of astaxanthin decreased linear in all samples (linear coefficient more than 98%), but the amount of final astaxanthin in different samples was significantly different from each other (p <0.5). Reducing the temperature and relative humidity of the storage environment resulted in better preservation of astaxanthin in microcapsules and microcapsules containing optimal wall composition and equal composition of each walls at 4 ° C and relative humidity of 52% had the highest stability of astaxanthin with half-life 94.93 and 92.42 days, respectively compared to other microcapsules

Evaluation of the Efficiency of Sulfur Dioxide Releasing Acetate Cellulose Sheets on the Shelf life of Kiwi Fruits in the Cold Store

The aim of the present study was to evaluate the efficiency of sulfur dioxide release sheets on the basis of acetate cellulose film to control the growth of molds, especially botrytis cinerea, during the storage period of kiwifruit. For this purpose, the storage of kiwifruit inoculated with botrytis cinerea in the presence of one and dual sulfur dioxide releasing sheets (containing 30 and 50% metabisulfit salts, respectively) on the acetate cellulose bed was investigated. After 15 days of storage (9 days in cold store and 7 days in ambient temperature), the least bursting and crushing (4.5%) was obtained in the presence of single-stage sheets that were placed on the surface and bottom of the packages. Also, in the ninth day, mold was not observed in the 60% of packages in the presence of sulfur dioxide releasing sheets. On the 15th day, the amount of total sugar, acidity, firmness, residual sulfur, and soluble solids in packaged kiwis in the presence of two dual releasing sheets placed on the surface and bottom of packages were, respectively, 9.9 g/100 g, 1.09%, 4.75 N, 0.24 mg/g and 12.21%. In general, it can be said that sulfur dioxide releasing sheets have an effective function on cold storage in increasing the shelf life of fruits, especially fruits that are attacked by gray mold