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This study was carried out to evaluate the effect of pretreatments prior drying as well as drying temperature on quality of the dried mushroom. Rehydration ratio and color of the dried product are the most effective parameter for judging and evaluating the drying process. Pleurotus ostreatus and Pleurotus eryngii samples were pretreated by different solutions (NaCl, citric acid and sodium metabisulfite) at room temperature and at 96± 2 o C. Pretreated and control mushroom samples were dried by hot air at 50, 60 and 70 o C until reached to constant weight. The dried product was evaluated immediately after drying. P. ostreatus required from 7-12 hr, while P. eryngii required 6.5-11 hr to reach moisture content around 7% depending on pretreatment and drying temperature. Control sample dried by using any tested drying temperature recorded the highest rehydration ratio compared to other pretreated samples dried at the same drying temperature. Also, steeped dried samples had higher rehydration ratio than blanched ones. Samples steeped in sodium metabisulfite (SMS) prior drying had the lowest browning index, while those blanched in NaCl or citric acid had the highest browning index values. Drying process caused a considerable decrement in protein content and a severe reduction in total microbial counts of mushroom samples. Sensory evaluation revealed that control and samples steeped in SMS or NaCl prior drying at 50 o C got higher scores than the others. According to the results obtained it could be clearly concluded that, steeping P. ostreatus and P. eryngii samples in NaCl, citric acid or Sodium metabisulfite (0.1% each at room temperature) for 10 min. prior drying at 50 o C prevented browning especially with SMS. Also, steeping treatment resulted satisfactory rehydration ratio for dried products even they were lower than the untreated (control) sample.

Among higher fungi, Pleurotus is well acknowledged as an economically important genus. This may be attributed to its worldwide distribution, its broad adaptability to various conditions. Pleurotus citrinopileatus has a very attractive yellow color, good culinary properties, and has highly appreciated commercial potentials in many countries. This Pleurotus type was newly introduced to Egypt from China. This investigation was carried out to determine the cultivation possibility of this new mushroom type under the domestic conditions using the cheap available agro-wastes throughout three consecutive seasons. Rice straw, wheat straw and sawdust were used as base substrates for growing media formula. Growing parameters such as spawn run (incubation time), pinheads initiation, fruit bodies development (maturation) time, yield and biological efficiency (BE%) were studied. Main chemical constituents of the P.citrinopileatus were estimated. The yielded fruit bodies were dried either by sun or oven and drying data was recorded. Spawn run time ranged from (18-28), (18-30), (16-26) days for first, second and third season, respectively .Fruit bodies development (maturation) were 6-8 days for all tested media. The total fresh yield ranged from 137-393 g/ kg wet media with BE% of 38-115% for all media through the tested three seasons. The mixture of rice straw and wheat straw media gave the highest yield, while the sawdust media produced the lowest one. P.citrinopileatus fruit bodies contained 85.90-87.37% moisture content, 22.84-26.01% crude protein, 2.59-3.23% crude fat, 7.76-9.06% ash and 63.77-65.58% total carbohydrates on dry weight basis. The fruit bodies required 35-55 hrs. for sun drying, while they took 9-14 hrs for oven dehydration. Control and sulfured samples dried either by sun or oven showed superior values for rehydration ratio and sensory characteristics. According to the obtained data it could be recommended that P. citrinopileatus cultivation could be spread and encourged using the available materials in Egypt.

No abstract

Peas are one of the most important vegetable crops in Egypt. The shelf life of fresh peas is shorter than processed ones, so the use of modified atmosphere packaging (MAP) can play an important role in extending their shelf-life. Studies were carried out on modified atmosphere packaging of peas for variety Master B. The peas were packaged in lowdensity polyethylene (LDPE) and polyproplyene (PP) of 50 and 55 mµ thickness respectively. These packages were stored at 0, 5, 15C° and room temperature and evaluated for quality at different storage periods. The treatments comprised modified atmosphere packaging (MAP) 3% O2 + 7% CO2 + 90% N2 headspace and normal air (control). The shelf life of peas packaged in (LDPE) and (PP) under MAP was 38, 20, 9 & 5 days and 33, 17, 8 & 5 when stored at 0, 5, 15C° and room temperature, respectively. The quality indices like total soluble solids, moisture conten, pH value, microbiological analysis, weight loss and decay were determined. The shelf life of peas was 20 and 17 days when packaged in (LDPE) and (PP) with (MAP) at 5C°, but it was 17, 15 days with normal air (control) at the same temperature. Statistical analysis showed significant effect of temperature and storage period on total soluble solids, moisture content, pH value, microbiological analysis, weight loss and decay of peas.