Search

In the first experiment, the effect of two novel Lactobacillus plantarum strains was studied on the fermentation of spent mushroom substrate (SMS) through 10d of ensiling. Based on lactic acid production and lactic acid bacteria population, L. plantarum KU5 was identified as the best strain for fermentation with a 5-L bag silo. Spent mushroom substrate was ensiled with 0.5% (v/w) L. plantarum KU5 without or with 5% molasses. Silages treated with microbial inoculant and molasses had the lowest pH and the highest fermentative odors. In a second set of experiments similar to the above 5-L silo study, the simultaneous application of L. plantarum KU5 inoculant and molasses to 80-L silos improved fermentability and aerobic stability of SMS silages. For similar treatment using ton-bag silos, aerobic stability decreased and NH3-N content increased dramatically. In conclusion, sawdust-based SMS for animal use was successfully ensiled with L. plantarum KU5 inoculant and molasses., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Autotrophic nitrogen removal via ammonia oxidizing (AOB) and anaerobic ammonium oxidizing (anammox) bacteria was evaluated for treatment of a dilute 50mg/L ammonia-containing solution in a single-stage nitrogen-removal filter at 25°C. Important was an external oxygenation system that permitted close control and measurement of oxygen supply, a difficulty with the generally used diffused air systems. Hydraulic retention time (HRT) was reduced in steps from 15 to 1h. At 1h HRT, total nitrogen (TN) removals varied between 73% and 94%, the maximum being obtained with a benchmark oxygenation ratio of 0.75mol O(2)/mol ammonia fed. At higher ratios, nitrate was formed causing TN removal efficiency to decrease. With lower ratios, TN and ammonia removals decreased in proportion to the decrease in BOR. When operating at or below the BOR, nitrate formation equaled no more than 2% of the ammonia removed, a value much less than has previously been reported., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A small-silo study was conducted to develop an effective ensiling storage method for the use of cotton waste-based spent mushroom substrate (SMS) as an animal feed. The SMS was ensiled with 5% molasses (DM basis), 0.5% (v/w) lactic acid bacteria (LAB, Lactobacillus plantarum) inoculant or 0.5% (v/w) yeast (Saccharomyces cerevisiae) inoculant. The treatments included 100% SMS (control), 95% SMS+5% molasses (T1), 95% SMS+5% molasses+0.5% LAB (T2) and 95% SMS+5% molasses+5% LAB+0.5% yeast (T3). The treatments were ensiled for 10. Change in chemical compositions was little (P>0.05) according to the ensiling process and treatments. Compared with those before ensiling, 100% SMS (control) after ensiling showed unstable fermentative properties with high pH (5.2) and little lactic acid production. Compared with the ensiled control, treatments (T1, T2 and T3) resulted in decreased pH, 18-20 times higher concentrations of lactic acid, and greater populations of total bacteria (P<0.07), LAB and yeast (P<0.07). The addition of 5% molasses, 0.5% LAB and 0.5% yeast (T3) to the SMS resulted in the lowest pH (4.25) and the greatest microbial populations. Treatment T3 was selected for a large scale silo study which was ensiled for 10, 20 and 30 d. As in the small-silo study, the T3 treatment showed favorable fermentative and microbial parameters, compared with the control, by decreasing pH and increasing lactic acid concentrations, LAB and yeast populations. The minimum ensiling period was 20 d, when pH was reasonably low and LAB and yeast populations were greatest. In conclusion, molasses and microbial inoculation improved silage quality of SMS.

A study was conducted to determine the effect of broiler poultry litter (BL) supplementation to spent mushroom substrate (SMS) on its storage and feed-nutritional value improvement. In Exp. 1, the sawdust-based SMS from a king oyster mushroom (Pleurotus eryngii) farm was mixed with BL at 0%, 25%, 50%, 75% and 100% levels on a wet basis and deepstack stored for short-term (1-wk) and long-term (3-wk). At 1-wk of short-term deepstack storage, SMS with more than 50% BL levels showed favorable conservation. At 3-wk of long-term storage, all treatments except for BL 100% had a serious fungal problem. Based on chemical parameters, BL-blending to SMS practically improved the feed-nutritional value of the mixtures. Since the deepstacking method was not effective for long term storage, in Exp. 2 SMS ensiled with or without BL was attempted to improve long-term (3-wk) storage. All the ensiled treatments (SMS 100%, SMS 75%+BL 25% and SMS 50%+BL 50%) had desirable fermentation. As in deepstacking, BL-blending to SMS improved the nutritive value of the ensiled mixtures. The populations of total bacteria, lactic acid bacteria and yeast were highest (P<0.05) when 75% SMS was blended with 25% BL. In conclusion, blending 50% or more BL with SMS was effective for the short-term (1-wk) deepstack storage. For long-term (3-wk) storage of SMS, an ensiling method was effective with or without the addition of BL.

This study was conducted to determine the effects of lactic acid bacteria (LAB, Lactobacillus salivarius) inoculation on the microbial, physical and chemical properties of food waste mixture (FWM) stored at ambient temperature (25 degrees C) for 10 and 30 days. A complete pig diet including restaurant food waste, bakery by-product, barley and wheat bran, and broiler poultry litter was amended with LAB at the levels of 0.1%, 0.2%, 0.5% and 1.0% and fermented anaerobically. These treatments were compared with intact FWM before storage and non-anaerobically stored FWM. Non-anaerobic storage of FWM showed microbial putrefaction with the loss (P < 0.05) of water and water soluble carbohydrate (WSC) and increases (P < 0.005) in protein and fiber. Anaerobic fermentation of FWM with or without LAB seemed effective in both 10- and 30-day-storage. The addition of LAB inoculants to FWM showed a linear trend (P < 0.05) toward an increase in the number of total and lactic acid bacteria and toward the nutritional improvement with WSC increased and fiber decreased. Long-term (30 days) storage resulted in consistent reduction (P < 0.05) in numbers of total and lactic acid bacteria and pH and showed little change in chemical components, compared with short-term (10 days) storage. On the basis of these results, LAB inoculation improved fermentative characteristics of FWM. Among anaerobic treatments, further WSC increase and NDF reduction did not occur (P > 0.05) when LAB-added levels were over 0.2%. Based on these observations the optimum level of LAB addition to FWM was 0.2%.

This study was conducted to evaluate the effects of feeding aerobically processed and vacuum-dried food waste-broiler litter and bakery by-product mixture to finishing pigs on performance, carcass characteristics, meat quality and taste panel test. A corn-soy diet (Control) was replaced with food waste mixture (FWM) at dietary levels of 25% (25% FWM) and 50% (50% FWM) on a dry matter (DM) basis. Diets were fed to a total of 45 pigs (mean body weight 69.4kg) during the eight wk of finishing period. After slaughtering, longissmus muscle at 24h postmortem was used for meat quality analysis. Restaurant food waste was high in protein (22.0%) and fat (23.9%). Supplementing a corn-soy diet with FWM increased (P<0.05) feed DM intake, did not alter (P>0.05) average daily gain, decreased (P<0.05) feed efficiency especially for 50% FWM treatment, and substantially reduced (P<0.05) feed cost, compared with feeding a corn-soy diet only. Feeding FWM up to 50% did not affect (P>0.05) carcass characteristics (carcass weight, dressing percentage, backfat thickness and carcass grade), meat fatty acid composition, meat quality (marbling score, pH, water holding capacity, drip loss, L*, a*, b* values, Warner-Bratzler shear force, cooking loss), and taste panel test (flavor, taste, tenderness, juiciness, and overall acceptance) compared with feeding a corn-soy diet. However, meat color was paler (P<0.05) for 50% FWM fed animals than a corn-soy diet fed animals. Meat color was the only limiting factor when FWM was fed to finishing pigs. In conclusion, aerobically processed and vacuum-dried food waste-broiler litter and bakery by-product mixture was similar to a corn-soy diet in feed value for finishing pigs.