Chemical Characteristics and Storage Stability of Pickled Garlic Prepared Using Different Processes

Abstract

Three processes for preparing peeled pickled garlic were studied: (P) packing directly with an acidified brine, followed by pasteurization (90°C, 8 min); (B) blanching with hot water (90°C, 15 min) before packing, followed by a preservation treatment (pasteurization, preservatives + refrigeration); and (MB) same as B, except that microwave blanching was used (120g garlic cloves, 825W, 1.5 min). All products were microbiologically stable but fructans were hydrolyzed during storage at 27°C. A green pigment was also apparent in (P). Products from (B) or (MB) had better quality than that from (P). Most stable and best quality products resulted from the blanching treatments and water blanching resulted in the product with best color.addition of the starter, and to inactivate softening enzymes (Fleming et al., 1983). Blanching with boiling water for 15 min has been used for deactivating alliinase before determination of alliin in garlic products (Mochizuki et al., 1988). Blanching with microwave energy has been reported to have advantages over conventional hot water or steam blanching by reduction of process times, energy and water usage and improvement of product quality (Ponne et al., 1994).Our objectives were to prepare pickled garlic using different processes (direct packing, packing after blanching with hot water, and packing after blanching with microwave energy) and to study changes in chemical characteristics, firmness and color during preparation and storage. MATERIALS & METHODS Preparation of pickled garlicFresh garlic bulbs were obtained from a market in Seville (Spain). After cracking the bulbs to separate the cloves and peeling the outer covering (Fig. 1), defective and smallest cloves were discarded. The remaining peeled cloves were washed with tap water and separated into three lots. One lot was directly packed into 10 " 8 Par" glass bottles (115g garlic cloves and 115 mL cover liquor capacity) using, as cover liquor, a brine (5% NACl) acidified with a lactic acid-acetic acid mixture. The concentration of each acid (0.74%, w/v) in the cover brine was calculated to give a pH of 4.0 after equilibrium between garlic cloves and brine. Half of the packed product (5 bottles) was pasteurized for 8 min in a water bath at 90°C (cover brine was added at Ϸ70°C) and the remainder was left as non-pasteurized control. All bottles were stored in a room maintained at 27 ± 2°C.A second lot of peeled garlic cloves was blanched in water at 90°C for 15 min and then packed. A portion of blanched-garlic cloves was packed into 10 "8 Par" glass bottles with the acidified cover brine used previously (added at ‫°07ف‬C). Five bottles were pasteurized at 90°C for 5.5 min and the rest left as non-pasteurized control. Both products were stored at 27 ± 2°C. The remaining portion of blanched garlic cloves was also packed with the same cover brine, except it was fortified with 0.27% potassium sorbate and 0.24% sodium benzoate, and maintained under refrigeration (4°C) during storage. The third lot of peeled garlic cloves was blanched usi...

Storage quality of chopped garlic as influenced by organic acids and high-pressure treatment

“…Hydrolysis of fructans in garlic during storage reportedly resulted in considerable increases in the concentrations of fructose and glucose without changes in the sucrose level. 28 Nonetheless, changes in the glucose content of chopped garlic during storage were not correlated with discolouration in our study.…”

EFFECT OF Γ-Irradiation ON THE PHYSICOCHEMICAL PROPERTIES, AND MICROBIAL AND SENSORY QUALITIES OF COLD-STORED ONION PUREE

“…These include Maillard reaction and enzymatic browning as well as process conditions, such as pH, acidity, packaging material, and duration and temperature of storage. Generally, onion puree should have a light green to cream color, but browning of onion products during preparation and storage has been recognized as a major quality problem (Rejano et al . 1997).…”

Effect of Sulfites and Sorbates on the Preservation and Color of Pickled Blanched Garlic under Different Storage Conditions

“…Briefly, for the determination of free sulfite, a 50-mL aliquot of brine sample was placed in a 250-mL Erlenmeyer flask, and 2 g of KI, 1 mL of 50 mM ethylenediaminetetraacetic acid, 0.5 mL of 2% starch solution and 3 mL of 10% (v/v) H2SO4 were added; the mixture was immediately and rapidly titrated with 0.02 N I2 to the lightest blue end point. Analytical procedures for pH, titratable acidity and sodium chloride were the same as described by Rejano et al (1997). Free sulfite values were corrected for nonSO2 iodinereducing substances by performing titration in another 50-mL aliquot of sample, prior to the addition of 5 mL of 0.7% (v/v) acetaldehyde and incubation for 30 min.…”