We have investigated accelerating the ripening of Pecorino Umbro
cheese
by adding crude cytoplasmic extract from Pseudomonas fluorescens,
non-starter
lactic acid bacteria (NSLAB) or cheese slurry. Microbiological and biochemical
analyses and sensory evaluation were carried out on control and experimental
cheeses over 28 d ripening. In the cheeses containing NSLAB or slurry,
counts of
mesophilic lactobacilli ranged from log 7·6 at day 1 to ∼log
8·6 cfu/g after 28 d
ripening, ∼2 log cycles higher than in the control cheese. All the
experimental
cheeses contained higher levels than the control of total free amino acids
and N
soluble at pH 4·6 and in 120 g trichloroacetic acid/l. Compared
with the control,
higher aminopeptidase and dipeptidase activities were found in the cheeses
containing NSLAB and slurry, and especially in those containing the Pseudomonas
enzyme. The cheeses containing NSLAB or slurry were characterized by an
accumulation of short peptides (Mr<2000)
detected by FPLC. Although the cheese
containing enzyme had an atypical flavour, the addition of mesophilic lactobacilli
reduced from 60 to 28 d the ripening period of Pecorino Umbro cheese, without
the
appearance of off flavour.
Accelerated Ripening in Chemically Fueled Emulsions
