FSC-342 Midterm (Maybe): Lecture 19 - Molds

What type of organisms are fungi?

Eukaryotic

What key cellular structures do fungal cells possess that bacteria lack?

Nuclear membrane, nucleus with chromosomes, organelles (Golgi, ER)

What are the two main forms of fungi?

Molds (multicellular) and yeasts (unicellular)

Which yeast is oval shaped and commonly used in food production?

Saccharomyces cerevisiae

What are mycotoxins?

Secondary metabolites produced by molds that can harm human health

What foods are toxigenic molds most commonly found in?

Plant-derived foods (cereals, grains, nuts)

What health effects are associated with aflatoxins?

Acute liver damage, liver cirrhosis, tumor induction, immunosuppression

Which historical event in Japan was linked to Penicillium contamination of rice?

Yellow Rice Disease

What 1960s event was caused by aflatoxin-contaminated peanut meal?

Turkey 'X' Disease

Which three genera of molds are emphasized in food safety?

Aspergillus, Penicillium, Fusarium

Which species of Aspergillus produce aflatoxins?

Aspergillus flavus, Aspergillus parasiticus, Aspergillus nomius

What toxins does Aspergillus flavus produce?

Aflatoxins B1 and B2, cyclopiazonic acid

What toxins do Aspergillus parasiticus and nomius produce?

Aflatoxins B1, B2, G1, and G2

Which Aspergillus species is widely distributed and produces ochratoxin?

Aspergillus ochraceus

Which Aspergillus species is used in soy sauce production?

Aspergillus oryzae

Which crops are most commonly invaded by aflatoxigenic molds?

Corn, peanuts, cottonseed

Which discovery in 1929 led to the recognition of mycotoxins?

Penicillin

What is the most important toxin produced by Penicillium species?

Ochratoxin A

Which Penicillium toxin is a renal toxin for pigs and dogs?

Citrinin

What foods are commonly contaminated with citrinin?

Cereals (rice, wheat, corn), milled grains, flour

Which toxin is produced by Penicillium expansum during apple and pear rot?

Patulin

Is patulin stable during apple juice storage?

Yes

Does pasteurization significantly reduce patulin levels?

No, less than 20% reduction at 90°C for 10 seconds

Which mold group is a major mycotoxigenic group in cereal grains and beans?

Fusarium

What are the key toxins produced by Fusarium species?

Deoxynivalenol, fumonisins, trichothecenes

Which Fusarium toxin is most often associated with human illness?

Deoxynivalenol

Which mold contaminates grains, fruits, and vegetables?

Alternaria

Which mold causes ergotism?

Claviceps purpurea

What parameter is important for controlling aflatoxin production?

Water activity (a_w)

Which chemicals can oxidize and partially destroy aflatoxins?

Ozone and hydrogen peroxide

What gas treatment can reduce aflatoxins by 95–98%?

Anhydrous ammonia

Which countries use ammonia detoxification commercially?

United States, France, Senegal