Shelf life prediction of straw mushrooms (Volvariella volvacea) based food enhancer using accelerated shelf life testing method

Food shelf life is related to food safety since consumers need to be informed an expired date of the food product. This study aims to determine shelf life of natural food enhancer based on straw mushroom (Volvariella volvacea) using Accelerated Shelf Life Testing (ASLT). Determination of shelf life was carried out at 30, 40, 50°C followed by descriptive sensory (colour, aroma, taste) and moisture content analysis for 28 days. Further data of those parameter over storage time were plotted into a graph to obtain a linear regression equation of zero-order and first-order. Then relationship between ln slope (k) and storage temperature 1/T (°K) was plotted in a linear regression to determine activation energy. Equation of linear regression from the lowest activation value then was used to calculate the shelf life of the product. The taste parameter on zero-order was used in shelf life determination as the critical quality because it has the smallest activation energy as 1708.39 cal/mol. The Arrhenius equation then was calculated using this value to obtain degradation constant (k). The results showed that shelf life of the straw mushroom based food enhancer were 77.58 days at 30°C, 70.85 days at 40°C and 65.07 days at 50°C.

ANALISIS PENDAPATAN USAHATANI DAN EFISIENSI PEMASARAN JAMUR MERANG (Volvariella volvacea) DI KABUPATEN KARAWANG

Jamur merang merupakan salah satu komoditas unggulan yang ada di Kabupaten Karawang. Pertumbuhan konsumsi jamur selalu meningkat setiap tahunnya. Permintaan per hari mencapai 4-10 ton, sementara penawarannya hanya berkisar 4-7 ton. Dengan demikian, komoditas ini sangat potensial untuk meningkatkan pendapatan pelaku agribisnis jamur merang. Penelitian ini bertujuan untuk menganalisis pendapatan yang diterima petani, pola saluran pemasaran dan efisiensi pemasaran jamur merang di Kabupaten Karawang. Metode penelitian yang digunakan adalah metode deskriptif dengan teknik penelitian survei. Data yang digunakan adalah data primer dan sekunder. Sampel ditentukan dengan cara non probabilistik dengan entry point adalah pelaku usaha utama (petani jamur), kemudian dilakukan penelusuran ke depan dan ke belakang (forward and backward) dengan menggunakan snowball sampling untuk mendapatkan sampel pada titik berikutnya. Metode Analisis yang digunakan adalah analaisis pendapatan, marjin pemasaran, keuntungan, farmer share dan efisiensi pemasaran. Hasil penelitian menunjukkan bahwa terdapat 6 pola saluran pemasaran jamur merang. Pelaku yang terlibat terdiri dari petani, bandar, pedagang besar, pengecer dan konsumen. Hasil analisis usahatani jamur merang menunjukkan bahwa nilai R/C sebesar 1,98. Nilai R/C >1 menunjukkan bahwa usaha yang dilakukan oleh petani jamur merang layak untuk diusahakan. Ditinjau dari marjin pemasaran, keuntungan, farmers’s share, efisensi pemasaran, semua saluran pemasaran dikategorikan efisien.

The cold - resistance mechanism of a mutagenic Volvariella volvacea strain VH3 with outstanding traits revealed by transcriptome profiling

Background The straw mushroom (Volvariella volvacea) is one of the important vegetables that is popular for its delicious taste. However, the straw mushroom is sensitive to low temperature, resulting in economic loss during transportation and storage. We obtained a novel straw mushroom strain, named VH3, via ultraviolet mutagenesis. Results Our study revealed that VH3 exhibited high cold resistance compared to an ordinary straw mushroom cultivar, V23. We found that the electrolyte leakages of VH3 were always significantly lower than that of V23 treated with 4 °C for 0 h, 2 h,4 h, 8 h, 16 h, and 24 h. Before cold treatment (0 h), there were no difference of MDA contents, SOD activities, and CAT activities between VH3 and V23. At the late stage (8 h, 26 h, and 24 h) of cold treatment, the MDA contents of VH3 were lower while both the SOD and CAT activities were higher than those of V23. To investigate the potential mechanisms of VH3 cold resistance, we performed transcriptome sequencing to detect the transcriptome profiling of VH3 and V23 after 0 h and 4 h cold treatment. Transcriptome sequencing revealed that 111 differentially expressed genes (DEG) between V23 (0 h) and VH3 (0 h) (V23–0_vs_VH3–0), consisting 50 up-regulated and 61 down-regulated DEGs. A total of 117 DEGs were obtained between V23 (4 h) and VH3(4 h) (V23–4_vs_VH3–4), containing 94 up-regulated and 23 down-regulated DEGs. Among these DEGs, VVO_00021 and VVO_00017 were up-regulated while VVO_00003, VVO_00004, VVO_00010, and VVO_00030 were down-regulated in V23–0_vs_VH3–0 and VH3–4_vs_V23–4. KEGG and GO analysis revealed that the 6 DEGs were annotated to pathways related to cold stress. Besides, the GA3 content was also decreased in VH3. Conclusions Collectively, our study first revealed that the increased cold resistance of VH3 might be caused by the expression change of VVO_00003, VVO_00004, VVO_00017, VVO_00021, and VVO_00030, and decreased GA3.

Energy Potential of Oil Palm Empty Fruit Bunch (EFB) Fiber from Subsequent Cultivation of Volvariella volvacea (Bull.) Singer

EFB and EFB-based mushroom compost (SMC) from Volvariella volvacea cultivation is a promising energy feedstock because it has adequate nutrient quality. The biochemical methane potential (BMP) and calorific value (CV) of this biomass are investigated. Other analyses such as proximate, compositional, and final analysis; thermogravimetric analysis (TGA); and Fourier transform infrared spectroscopy (FTIR) are also performed. The biomass samples consist of two types of EFB, namely fibers (F) and pellets (P) and SMC from the subsequent cultivation of Volvariella volvacea, with samples FS and PS from the first cultivation and FS2 and PS2 from the second cultivation. P produces the highest biological efficiency (BE) of 28% compared to 9.83% for F. Subsequent cultivation with FS and PS then produces only 2.9 and 6.83% of BE. A higher amount of methane is measured in samples P and PS2, while better biodegradability is observed in PS2 and FS2, suggesting that subsequent cultivation is a good pretreatment of the substrate for anaerobic digestion (AD). CV is highest in F (20.57 MJ/kg), followed by P (19.06 MJ/kg), which is comparable to commercial wood pellet. Samples F, FS, and FS2 have higher ash content, which is due to higher mineral content. The cellulose composition is reduced to almost 50% during cultivation due to fungal metabolism, which is also evidenced by FTIR analysis. TGA analysis revealed that EFB-based SMC exhibits higher weight loss during combustion compared to EFB, which reduces its thermal properties. SMC of EFB is a high potential biomethane feedstock, but not recommended as a fuel pellet.